WO2025020036A1

WO2025020036A1 - Quick clean-in-place and clean-out-of-place cleaning performance validation

Info

Publication number: WO2025020036A1
Application number: PCT/CN2023/108853
Authority: WO
Inventors: Jinsen Gao; Liang JI; Yan Zheng; Jiaying CAI; Linna Wang
Original assignee: Ecolab USA Inc
Current assignee: Ecolab USA Inc
Priority date: 2023-07-24
Filing date: 2023-07-24
Publication date: 2025-01-30
Anticipated expiration: 2026-01-24

Abstract

Methods and compositions for quickly validating the cleaning performance in clean-in-place (CIP) and clean-out-of-place (COP) systems and on surfaces in high traffic areas. The solution comprises alkali metal hydroxides; one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, monopersulfate; and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate. In some examples, the solution further comprises potassium tripolyphosphate, sodium tripolyphosphate, or other tripolyphosphates. A substrate is contacted with the solution and a color reaction may occur, indicating the presence of organic matter or non-organic soil. The color reaction may occur in less than 30 minutes and at temperatures from 10℃ to 60℃.

Description

QUICK CLEAN-IN-PLACE AND CLEAN-OUT-OF-PLACE CLEANING PERFORMANCE VALIDATION

BACKGROUND

Clean-in-place (CIP) and clean-out-of-place (COP) are two common methods used in the food, beverage, and pharmaceutical industries to clean and sanitize processing equipment. CIP systems are designed to clean equipment without the need for disassembly, allowing the cleaning process to be completed quickly and efficiently. In CIP systems, cleaning solutions are circulated through the equipment to remove any contaminants, and the solutions are then drained from the system. CIP systems are typically automated and can be programmed to run at specific intervals, reducing the need for manual cleaning and minimizing the risk of human error. CIP systems are commonly used in industries such as dairy, brewing, food, beverage, pharmaceutical, nutraceutical, and cosmetic production, where equipment must be sanitized frequently.

COP systems, on the other hand, are disassembled for cleaning. This process can be time-consuming and labor-intensive, but it is often necessary for equipment that does not lend itself to cleaning using CIP methods. COP systems are commonly used in the pharmaceutical industry, where the equipment must be thoroughly cleaned and sanitized to avoid cross-contamination. The disassembled equipment is then cleaned manually or using specialized cleaning systems before being reassembled and returned to service.

While CIP and COP cleaning programs are effective, they are not without challenges. For example, CIP systems rely on the flow of the cleaning solution in order to effectively clean. Areas that have low flow or are missing sufficient contact with the cleaning solution may not get cleaned and may subsequently develop contamination or biofilms. If the plant is running a CIP program, the plant may be unaware of this source of contamination because the nature of CIP programs makes it difficult to visually observe the interior of the equipment. COP equipment relies on the thoroughness of the person doing the cleaning. If the cleaning is not thorough, missed spots can also become a source of contamination.

It is against this background that the present disclosure is made.

SUMMARY

A variety of additional inventive aspects will be set forth in the description that follows. The inventive aspects can relate to individual features and to combinations of features. It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the broad inventive concepts upon which the embodiments disclosed herein are based.

A method of testing a surface for organic matter or non-organic soil comprises wiping a surface with a substrate; contacting the substrate with a solution comprising alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof; and detecting a color reaction on the substrate or in the solution.

Another embodiment is a method of testing water for organic matter or non-organic soil comprising: taking a sample of a source of water; mixing the sample and a solution comprising: alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof; and detecting a color reaction in the solution.

Another embodiment is a kit for testing for organic matter or non-organic soil comprising: a swab, absorbent ball, wipe, or test paper; a solution for detecting the presence of organic matter or non-organic soil comprising: alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate; and a test container configured to hold the solution, wherein the swab, absorbent ball, wipe, or test paper contacts the solution.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the description, illustrate several aspects of the present disclosure. A brief description of the drawings is as follows:

FIG. 1 is a schematic method of testing a surface for organic matter or non-organic soil, in accordance with an example of the disclosure.

FIG. 2 is a schematic method of testing a source of liquid for organic matter or non-organic soil, in accordance with an example of the disclosure.

FIG. 3A illustrates a color change produced by a solution containing tea powder, in accordance with an example of the disclosure.

FIG. 3B illustrates the color change produced by a solution with varying concentrations of milk, in accordance with an example of the disclosure.

FIG. 4A is a graphical representation of results of Example 2.

FIG. 4B is a graphical representation of results of Example 2.

FIG. 4C is a graphical representation of results of Example 2.

FIG. 4D is a graphical representation of results of Example 2.

FIG. 5A is a graphical representation of results of Example 3.

FIG. 5B is a graphical representation of results of Example 3.

FIG. 5C is a graphical representation of results of Example 3.

DETAILED DESCRIPTION

As used herein, weight percent (wt. %) , percent by weight, %by weight, and the like are synonyms that refer to the concentration of a substance as the weight of that substance divided by the total weight of the composition and multiplied by 100.

As used herein, the term “about” modifying the quantity of an ingredient in the compositions of the invention or employed in the methods of the invention refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like. The term about also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture. Whether or not modified by the term “about, ” the claims include equivalents to the quantities.

It should be noted that, as used in this specification and the appended claims, the singular forms “a, ” “an, ” and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to a composition containing “a compound” includes a mixture of two or more compounds. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

In the interest of brevity and conciseness, any ranges of values set forth in this specification contemplate all values within the range and are to be construed as support for claims reciting any sub-ranges having endpoints which are real number values within the specified range in question. By way of a hypothetical illustrative example, a disclosure in this specification of a range of from 1 to 5 shall be considered to support claims to any of the following ranges: 1-5; 1-4; 1-3; 1-2; 2-5; 2-4; 2-3; 3-5; 3-4; and 4-5.

As used herein, “clean” or “cleaning” refers to the removal or organic or inorganic soil. In some examples, “clean” or “cleaning” can refer to any process that aids in soil removal including bleaching, microbial population reduction, wiping, spraying, soaking, disinfecting, sterilizing, treating with UV sterilization, oxidizing, absorbing, using biochemical treatments, diluting, filtering, membrane filtering, treating, applying an antimicrobial agent, and combinations thereof.

As used herein the term, “consisting essentially of” refers to the listed ingredients and does not include additional ingredients that, if present, would affect the testing for a color change or the cleaning ability of the cleaners disclosed herein. The term “consisting essentially of” may also refer to a component of the solution. For instance, a solution may consist essentially of dichromate and would not include any other ingredients that would affect the color changing ability of the solution such as permanganate, either positively or negatively. As used herein the term “consisting essentially of” in reference to a method refers to the listed steps and does not include additional steps (or ingredients if a composition is included in the method) that, if present, would affect the testing a surface or sample of liquid.

Described herein are compositions and methods for quickly validating cleaning efficacy in CIP and COP systems. The compositions and methods of the present disclosure may be particularly suitable for systems where ensuring the cleanliness of CIP and COP systems is important for safety and regulatory compliance, such as food and beverage manufacturing, laboratory and pharmaceutical equipment, and surfaces in high-traffic areas.

Many of the processes that use CIP and COP methods for cleaning have hard-to-remove soils, especially if the soils have been thermally degraded. The term “thermally degraded” is used to refer to material that has been exposed to heat and as a result has undergone changes to the chemical structure of the material, such as denaturing and cross-linking reactions of proteins, carbohydrates, fats, and oils. This is common in systems where materials were heated during cooking, such as pasteurization of beverages. Other common soils that are cleaned with CIP and COP methods include organic matter, non-organic matter, proteins, fats, carbohydrates, starches, sugars, minerals, bacteria, viruses, biofilms, and complex soils that include more than one type of soil. The term “organic matter” refers to carbon-containing compounds that come from living organisms and include compounds that come from plants and animals. In particular, organic matter may refer to carbon-containing compounds that are used or produced in food and beverage production. This organic matter may cause fouling, where the matter is deposited on surfaces during food and beverage production.

While CIP and COP systems are designed to fully clean processing equipment, such as in the food, beverage, and pharmaceutical industries, the equipment is not always fully cleaned. This may occur if the solutions in the CIP or COP systems do not contact the surface to be cleaned at all or long enough, do not have enough mechanical action as a result of the turbulent flow of the solution or impact from spraying, or if the solutions do not have the requisite cleaning properties to fully clean the systems. Cleaning solutions, especially in CIP systems, are often reused multiple times, and thus over time the solutions lose their cleaning efficacy.

It may be desirable to test if the equipment and surfaces cleaned using the CIP and COP methods have been sufficiently cleaned. A schematic method 100 of validating cleaning performance is shown in FIG. 1. A surface is cleaned at step 110 using CIP or COP methods known in the art. The cleaned surface is then wiped with a substrate at step 112 that will pick up any organic matter or non-organic soil on the surface. The substrate can be a wipe, a swab, an absorbent ball, test paper, or any other suitable substrate. In some examples, the substrate is a single-use substrate that is disposable.

After wiping the surface, the substrate is contacted with a solution at step 114, which may be a concentrate solution or a diluted concentration. The solution may comprise alkali metal hydroxide, such as sodium hydroxide, potassium hydroxide, and lithium hydroxide. In some examples, the solution comprises a combination of alkali metal hydroxides. In some examples, the solution comprises a single alkali metal hydroxide, such as sodium hydroxide or potassium hydroxide. The hydroxide-containing compounds may provide alkalinity to the solution to allow for dissolution of soil and a color change when the solution contacts soil, which is discussed more below.

The solution may also comprise one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, monopersulfate, or combinations thereof.

The solution may also comprise one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate. Permanganate-containing and dichromate-containing compounds may act as oxidizing agents that produce a color. For example, permanganate may generate a purple, green, yellow, or other color depending on the level of organic matter or non-organic soil.

In some examples, the solution further comprises potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof. The tripolyphosphates act as water hardness scale inhibitors and chelators, which prevent or minimize the build-up of mineral deposits on surfaces due to dissolved minerals, such as calcium and magnesium. Additionally, metal ions may be sequestered to prevent deposition on surfaces.

In some examples, the solution further comprises up to 100 wt. %water. In some examples, the solution comprises from about 0.16 wt. %to about 99.9 wt. %water. In some examples, the solution comprises from about 0.16 wt. %to about 99 wt. %water, from about 0.16 wt. %to about 95 wt. %water, from about 0.16 wt. %to about 90 wt. %water, from about 0.16 wt. %to about 85 wt. %water, from about 0.16 wt. %to about 80 wt. %water, from about 0.16 wt. %to about 75 wt. %water, from about 0.16 wt. %to about 70 wt. %water, from about 0.16 wt. %to about 65 wt. %water, from about 0.16 wt. %to about 60 wt. %water, from about 0.16 wt. %to about 55 wt. %water, from about 0.16 wt. %to about 50 wt. %water, from about 0.16 wt. %to about 45 wt. %water, from about 0.16 wt. %to about 40 wt. %water, from about 0.16 wt. %to about 35 wt. %water, from about 0.16 wt. %to about 30 wt. %water, from about 0.16 wt. %to about 25 wt. %water, from about 0.16 wt. %to about 20 wt. %water, from about 0.16 wt. %to about 15 wt. %water, from about 0.16 wt. %to about 10 wt. %water, from about 0.16 wt. %to about 5 wt. %water, from about 0.16 wt. %to about 2.5 wt. %water, from about 0.16 wt. %to about 1 wt. %water, from about 0.16 wt. %to about 0.5 wt. %water, from about 0.5 wt. %to about 99.9 wt. %water, from about 1 wt. %to about 99.9 wt. %water, from about 2.5 wt. %to about 99.9 wt. %water, from about 5 wt. %to about 99.9 wt. %water, from about 10 wt. %to about 99.9 wt. %water, from about 15 wt. %to about 99.9 wt. %water, from about 20 wt. %to about 99.9 wt. %water, from about 25 wt. %to about 99.9 wt. %water, from about 30 wt. %to about 99.9 wt. %water, from about 35 wt. %to about 99.9 wt. %water, from about 40 wt. %to about 99.9 wt. %water, from about 45 wt. %to about 99.9 wt. %water, from about 50 wt. %to about 99.9 wt. %water, from about 55 wt. %to about 99.9 wt. %water, from about 60 wt. %to about 99.9 wt. %water, from about 65 wt. %to about 99.9 wt. %water, from about 70 wt. %to about 99.9 wt. %water, from about 75 wt. %to about 99.9 wt. %water, from about 80 wt. %to about 99.9 wt. %water, from about 85 wt. %to about 99.9 wt. %water, from about 90 wt. %to about 99.9 wt. %water, or from about 95 wt. %to about 99.9 wt. %water.

After the substrate has contacted the solution, the presence or absence of a color reaction is detected on the substrate or in the solution at step 116. For example, a swab may be dipped into the solution and the solution may have a color reaction that changes the color of the solution. In other examples, the substrate may be a test paper that is dipped in the solution, or the substrate is placed onto the test paper, and either the test paper or the substrate may produce a color reaction. A color reaction indicates the presence of organic matter or non-organic soil on the surface that was tested. The absence of a color reaction indicates the absence of organic matter or non-organic soil on the surface that was tested. The color reaction is discussed more below.

If there is organic matter, non-organic soil, or biofilm on the surface, the surface can then be re-cleaned at step 118, either by performing the CIP or COP methods again, or by other means such as wiping, spraying, soaking, treating with UV sterilization, or combinations thereof. The method can be repeated until no color reaction is detected, meaning that the organic matter or non-organic soil has successfully been cleaned. In some examples, “cleaning” can mean cleaning the surface until the color reaction produced and/or the absorbance reading taken from a sample is below an acceptable threshold level of soil. In some examples, “cleaning” may include applying an antimicrobial agent to the surface. In some examples, “cleaning” may include using alkaline to clean. In some examples, “cleaning” may include using acid to clean. In some examples, “cleaning” may include switching from an alkaline or neutral composition to an acid composition, or from an acid or neutral composition to an alkaline composition. A standard operating procedure may indicate that a specific absorbance reading or number of RLUs acts as a threshold, where a value above the threshold indicates an unacceptable level of soil and a value below the threshold indicates an acceptable level of soil.

Cleaning as described herein can use any suitable cleaning agents known in the art. Some non-limiting examples include peracids, peracetic acid, peroxyacetic acids, carboxylic acids, peroxycarboxylic acids, citric acid, lactic acid, peroxyoctanoic acid, methane sulfonic acid, organic acids including mono-, di-, and tricarboxylic acids such as formic, butyric, valeric, caproic, itaconic, trichloroacetic, oxalic, terephthalic, citric, acetic, lactic, malonic, maleic, succinic, hydroxyl succinic, adipic, octanoic, fumaric, methacrylic, methylsulfamic, propionic, gluconic, glutamic, glutaric, benzoic, tartaric, hydroxyacetic, and salicylic, inorganic acids such as phosphoric, nitric, sulfuric, sulfamic, quaternary ammonium compounds and salts thereof, sodium chlorite, alcohols such as isopropanol and ethanol, hydrogen peroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, surfactants, sodium hypochlorite, calcium hypochlorite, chlorine dioxide, enzymes such as proteases, lipases, cellulases, xylanases, and pectinases, rinse agents, combinations thereof, and any other suitable cleaning agent known in the art.

The solution may be prepared as a concentrate and diluted as a use solution. The concentrate solution comprises varying amounts of each component. In some examples, the alkali metal hydroxide is present in the concentrate solution from about 0.1 wt. %to about 45 wt. %. The alkali hydroxide may be present in the concentrate solution from about 0.1 wt. %to about 40 wt. %, from about 0.1 wt. %to about 35 wt. %, from about 0.1 wt. %to about 30 wt. %, from about 0.1 wt. %to about 25 wt. %, from about 0.1 wt. %to about 20 wt. %, from about 0.1 wt. %to about 15 wt. %, from about 0.1 wt. %to about 10 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.1 wt. %to about 2 wt. %, from about 0.1 wt. %to about 1 wt. %, from about 0.5 wt. %to about 45 wt. %, from about 1 wt. %to about 45 wt. %, from about 2 wt. %to about 45 wt. %, from about 5 wt. %to about 45 wt. %, from about 10 wt. %to about 45 wt. %, from about 15 wt. %to about 45 wt. %, from about 20 wt. %to about 45 wt. %, from about 25 wt. %to about 45 wt. %, from about 30 wt. %to about 45 wt. %, from about 35 wt. %to about 45 wt. %, or from about 40 wt. %to about 45 wt. %.

In some examples, the one or more oxidizing compounds is present in the concentrate solution from about 0.1 wt. %to about 40 wt. %. The one or more oxidizing compounds may be present in the concentrate solution from about 0.1 wt. %to about 35 wt. %, from about 0.1 wt. %to about 30 wt. %, from about 0.1 wt. %to about 25 wt. %, from about 0.1 wt. %to about 20 wt. %, from about 0.1 wt. %to about 15 wt. %, from about 0. 1 wt. %to about 10 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.1 wt. %to about 2 wt. %, from about 0.1 wt. %to about 1 wt. %, from about 0.5 wt. %to about 40 wt. %, from about 1 wt. %to about 40 wt. %, from about 2 wt. %to about 40 wt. %, from about 5 wt. %to about 40 wt. %, from about 10 wt. %to about 40 wt. %, from about 15 wt. %to about 40 wt. %, from about 20 wt. %to about 40 wt. %, from about 25 wt. %to about 40 wt. %, from about 30 wt. %to about 40 wt. %, or from about 35 wt. %to about 40 wt. %.

In some examples, the one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate is present in the concentrate solution from about 0.001 wt. %to about 5 wt. %. The one or more compounds may be present in the concentrate solution from about 0. 001 wt. %to about 4.5 wt. %, from about 0.001 wt. %to about 4 wt. %, from about 0.001 wt. %to about 3.5 wt. %, from about 0.001 wt. %to about 3 wt. %, from about 0.001 wt. %to about 2.5 wt. %, from about 0.001 wt. %to about 2 wt. %, from about 0.001 wt. %to about 1.5 wt. %, from about 0.001 wt. %to about 1 wt. %, from about 0.001 wt. %to about 0.5 wt. %, from about 0.001 wt. %to about 0.1 wt. %, from about 0.001 wt. %to about 0. 01 wt. %, from about 0.01 wt. %to about 5 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.5 wt. %to about 5 wt. %, from about 1 wt. %to about 5 wt. %, from about 1. 5 wt. %to about 5 wt. %, from about 2 wt. %to about 5 wt. %, from about 2.5 wt. %to about 5 wt. %, from about 3 wt. %to about 5 wt. %, from about 3.5 wt. %to about 5 wt. %, from about 4 wt. %to about 5 wt. %, or from about 4.5 wt. %to about 5 wt. %

In some examples, the potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof are present in the concentrate solution from about 0.01 wt. %to about 6 wt. %. The potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof may be present in the concentrate solution from about 0.01 wt. %to about 5.5 wt. %, from about 0.01 wt. %to about 5 wt. %, from about 0.01 wt. %to about 4.5 wt. %, from about 0.01 wt. %to about 4 wt. %, from about 0.01 wt. %to about 3.5 wt. %, from about 0.01 wt. %to about 3 wt. %, from about 0.01 wt. %to about 2.5 wt. %, from about 0.01 wt. %to about 2 wt. %, from about 0.01 wt. %to about 1.5 wt. %, from about 0.01 wt. %to about 1 wt. %, from about 0.01 wt. %to about 0.5 wt. %, from about 0.01 wt. %to about 0.1 wt. %, from about 0.1 wt. %to about 6 wt. %, from about 0.5 wt. %to about 6 wt. %, from about 1 wt. %to about 6 wt. %, from about 1.5 wt. %to about 6 wt. %, from about 2 wt. %to about 6 wt. %, from about 2.5 wt. %to about 6 wt. %, from about 3 wt. %to about 6 wt. %, from about 3.5 wt. %to about 6 wt. %, from about 4 wt. %to about 6 wt. %, from about 4.5 wt. %to about 6 wt. %, from about 5 wt. %to about 6 wt. %, or from about 5.5 wt. %to about 6 wt. %.

The concentrate solution can be prepared by combining the components in the above-described quantities into the concentrate solution. In some examples, the concentrate solution is used as the test solution to perform the method with no dilution. In other examples, the concentrate solution is diluted to an about 1%to an about 20%use solution. In some examples, the concentrate solution is diluted to an about 4%use solution.

If the concentrate solution is diluted, the quantities of each of the components of the solution will also be diluted. For example, as described above, a concentrate solution may include from about 0.1 wt. %to about 45 wt. %of alkali metal hydroxide. If the concentrate solution is diluted to a 4 %use solution, then the amount of alkali metal hydroxide in the diluted use solution would be from about 0.004 wt. %to about 1.8 wt. %. Accordingly, if the concentrate solution is diluted to a 4%use solution, then the amount of the one or more oxidizing compounds would be from about 0.004 wt. %to about 1.6 wt. %. If the concentrate solution is diluted to a 4%use solution, then the amount of the one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate would be from about 0.00004 wt. %to about 0.2 wt. %. If the concentrate solution is diluted to a 4%use solution, the amount of the potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof would be from about 0.0004 wt. %to about 0.24 wt. %. This disclosure contemplates every integer value within these ranges.

The concentrate solution may be diluted to an about 1%to an about 20%use solution. A diluted use solution within this dilution range may include from about 0.001 wt. %to about 9 wt. %, from about 0.001 wt. %to about 8 wt. %, from about 0.001 wt. %to about 7 wt. %, from about 0.001 wt. %to about 6 wt. %, from about 0.001 wt. %to about 5 wt. %, from about 0.001 wt. %to about 4 wt. %, from about 0.001 wt. %to about 3 wt. %, from about 0.001 wt. %to about 2 wt. %, from about 0.001 wt. %to about 1 wt. %, from about 0.001 wt. %to about 0.5 wt. %, from about 0.001 wt. %to about 0.1 wt. %, from about 0.1 wt. %to about 9 wt. %, from about 0.5 wt. %to about 9 wt. %, from about 1 wt. %to about 9 wt. %, from about 2 wt. %to about 9 wt. %, from about 3 wt. %to about 9 wt. %, from about 4 wt. %to about 9 wt. %, from about 5 wt. %to about 9 wt. %, from about 6 wt. %to about 9 wt. %, from about 7 wt. %to about 9 wt. %, or from about 8 wt. %to about 9 wt. %of the alkali metal hydroxide.

A diluted use solution within the dilution range of about 1 %to about 20 %may include from about 0.001 wt. %to about 8 wt. %, from about 0.001 wt. %to about 7 wt. %, from about 0.001 wt. %to about 6 wt. %, from about 0.001 wt. %to about 5 wt. %, from about 0.001 wt. %to about 4 wt. %, from about 0.001 wt. %to about 3 wt. %, from about 0.001 wt. %to about 2 wt. %, from about 0.001 wt. %to about 1 wt. %, from about 0.001 wt. %to about 0.5 wt. %, from about 0.001 wt. %to about 0.1 wt. %, from about 0.1 wt. %to about 8 wt. %, from about 0.5 wt. %to about 8 wt. %, from about 1 wt. %to about 8 wt. %, from about 2 wt. %to about 8 wt. %, from about 3 wt. %to about 8 wt. %, from about 4 wt. %to about 8 wt. %, from about 5 wt. %to about 8 wt. %, from about 6 wt. %to about 8 wt. %, or from about 7 wt. %to about 8 wt. %of the one or more oxidizing compounds.

A diluted use solution within the dilution range of about 1 %to about 20 %may include from about 0.00001 wt. %to about 1 wt. %, from about 0.00001 wt. %to about 0.5 wt. %, from about 0.00001 wt. %to about 0.1 wt. %, from about 0.00001 wt. %to about 0.01 wt. %, from about 0.00001 wt. %to about 0.005 wt. %, from about 0.00001 wt. %to about 0.001 wt. %, from about 0.00001 wt. %to about 0.0005 wt. %, from about 0.00001 wt. %to about 0.0001 wt. %, from about 0.00001 wt. %to about 0.00005 wt. %, from about 0.00005 wt. %to about 1 wt. %, from about 0.0001 wt. %to about 1 wt. %, from about 0.0005 wt. %to about 1 wt. %, from about 0.001 wt. %to about 1 wt. %, from about 0.005 wt. %to about 1 wt. %, from about 0.01 wt. %to about 1 wt. %, from about 0.1 wt. %to about 1 wt. %, or some about 0.5 wt. %to about 1 wt. %of the one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate.

A diluted use solution within the dilution range of about 1 %to about 20 %may include from about 0.0001 wt. %to about 1.2 wt. %, from about 0.0001 wt. %to about 1 wt. %, from about 0.0001 wt. %to about 0.5 wt. %, from about 0.0001 wt. %to about 0.1 wt. %, from about 0.0001 wt. %to about 0.05 wt. %, from about 0.0001 wt. %to about 0.01 wt. %, from about 0.0001 wt. %to about 0.005 wt. %, from about 0.0001 wt. %to about 0.001 wt. %, from about 0.0001 wt. %to about 0.0005 wt. %, from about 0.0005 wt. %to about 1.2 wt. %, from about 0.001 wt. %to about 1.2 wt. %, from about 0.005 wt. %to about 1.2 wt. %, from about 0.01 wt. %to about 1.2 wt. %, from about 0.05 wt. %to about 1.2 wt. %, from about 0.1 wt. %to about 1.2 wt. %, from about 0.5 wt. %to about 1.2 wt. %, or some about 1 wt. %to about 1.2 wt. %of the potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof.

In some examples, the concentrate solution or the use solution may have a pH from about 9.5 to about 13.5. In some examples, the concentrate solution or the use solution may have a pH from about 9.5 to about 13, from about 9.5 to about 12, from about 9.5 to about 11, from about 9.5 to about 10, from about 10 to about 13.5, from about 11 to about 13.5, or from about 12 to about 13.5.

As used herein, “solution, ” unless indicated otherwise, can refer to the concentrate solution, the diluted use solution, or both. When the solution and the substrate are contacted, if there is organic matter or non-organic soil present, a color reaction occurs. The color change produced by the color reaction will depend on the components included in the solution. For example, if the solution comprises potassium permanganate, sodium permanganate, or another permanganate compound, the solution may be a purple color before the solution contacts the substrate with organic matter or non-organic soil. If the permanganate-containing solution contacts a substrate with organic matter or non-organic soil, a color reaction occurs that changes the purple color to a green or yellow or light purple color. In other examples, if the solution comprises a dichromate compound, the solution will be orange prior to contacting the substrate. If a dichromate-containing solution contacts a substrate with organic matter or non-organic soil, a color reaction occurs that changes the orange solution to green.

In some examples, this color reaction occurs in less than 30 minutes, in less than 20 minutes, in less than 10 minutes, in less than 5 minutes, in less than 1 minutes, in less than 30 seconds, or in less than 10 seconds. FIG. 3A shows an example of a color reaction after 10 minutes. In some examples, the color reaction is observed at temperatures from about 10 ℃ to about 60 ℃. In some examples, the color reaction is observed at from about 10 ℃ to about 55 ℃, from about 10 ℃ to about 50 ℃, from about 10 ℃ to about 45 ℃, from about 10 ℃ to about 40 ℃, from about 10 ℃ to about 35 ℃, from about 10 ℃ to about 30 ℃, from about 10 ℃ to about 25 ℃, from about 10 ℃ to about 20 ℃, from about 10 ℃ to about 15 ℃, from about 15 ℃ to about 60 ℃, from about 20 ℃ to about 60 ℃, from about 25 ℃to about 60 ℃, from about 30 ℃ to about 60 ℃, from about 35 ℃ to about 60 ℃, from about 40 ℃ to about 60 ℃, from about 45 ℃ to about 60 ℃, from about 50 ℃ to about 60 ℃, or from about 55 ℃ to about 60 ℃. In some examples, the color reaction is observed at room temperature, which is about 15 ℃ to about 25 ℃.

In some examples, the color reaction is observed visually by eye. In other examples, the color reaction may be observed using an instrument such as a color comparator, colorimeter, or spectrometer. The color comparator or colorimeter may measure the color change by evaluating the wavelength of the light produced by the color reaction on the visible light spectrum. In some examples, the color reaction is measured between about 400 nm and about 700 nm. The color comparator or colorimeter, or any other instrument suitable of reading absorbance wavelengths, may detect the color reaction and measure the absorbance of the color after the color reaction. In some examples, a control sample with no color reaction may be measured by the instrument and compared to the solution or substrate after the color reaction. The absorbance after the coloration and/or the change in color may be evaluated using digital images or graphical analysis. In some examples, software or a computer program associated with the instrument may measure the change in absorbance before and after the color reaction. In some examples, the instrument may be a portable instrument capable of being used by the ordinary user, such as by cleaning staff or technicians.

In some examples, a “color change” refers to a color change that is visible to the naked human eye. In some examples, a “color change” refers to a color change that is measurable by an instrument. The color change can be quantified in terms of absorbance units (AU) or the change in wavelength in nanometers (nm) of the color. In some examples, a color change can be quantified by an instrument in ppm and then converted to absorbance units.

In some examples, a color change is present if there is a change in wavelength of 5 nm or more, a change in wavelength of 10 nm or more, a change in wavelength of 15 nm or more, a change in wavelength of 20 nm or more, a change in wavelength in 25 nm or more, a change in wavelength in 40 nm or more, a change in wavelength of 50 nm or more, or a change in wavelength of 100 nm or more. In some examples, a color change is present if there is a change in the absorbance units of a sample as measured by an instrument. The color change may be a change in 0.1 absorbance units or more, a change in 0.2 absorbance units or more, a change in 0.3 absorbance units or more, a change in 0.4 absorbance units or more, a change in 0.5 absorbance units or more, a change in 0.7 absorbance units or more, or a change in 1 absorbance unit or more.

The above-described method may be used in a CIP system or a COP system. In some examples, the CIP system is in a food plant, a beverage plant, or a pharmaceutical plant. In some examples, the method is used to test a surface in a food plant, a beverage plant, a pharmaceutical plant, a hospital, a kitchen, a hotel, a laboratory, or an office. The method may be used to validate cleaning efficacy on any surface that may have organic matter or non-organic soil.

In some examples, the solution used for testing a surface does not contact the surface. For example, a sterile substrate, such as a swab, may be used to wipe a surface to be tested, and the swab may be dipped in the solution to produce the color reaction. In such examples, the solution does not contact the surface and the surface does not need to be rinsed off after testing. In other examples, the solution may be contacted with a substrate, and the substrate then contacts the surface to be tested. For example, the solution may be pre-loaded onto a wipe that is then wiped onto a surface to be tested. In such example, the color reaction may occur on the wipe that can be observed visually or with an instrument. The solution does not comprise organic matter and thus does not need to be rinsed off the surface after testing, even if the solution contacted the surface.

In some examples, the method 100 of validating cleaning performance uses a solution that consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof. In some examples, the solution consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, and combinations thereof. In some examples, the solution consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium dichromate, sodium dichromate, and combinations thereof.

Also disclosed herein is a method 200 for testing a source of liquid for organic matter or non-organic soil, as shown in FIG. 2. The liquid can comprise water, saline, a beverage, sterile liquid, or any other liquid to be tested for organic matter or non-organic soil. A sample of the liquid is taken from a source of the liquid at step 210, and the sample is mixed with a solution for testing the source of liquid for organic matter or non-organic soil at step 212. The solution may comprise alkali metal hydroxide, such as sodium hydroxide, potassium hydroxide, and lithium hydroxide. In some examples, the solution comprises a combination of alkali metal hydroxides. In some examples, the solution comprises a single alkali metal hydroxide, such as sodium hydroxide or potassium hydroxide.

The solution may also comprise one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, monopersulfate, or combinations thereof. The solution may also comprise one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate. In some examples, the solution further comprises potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof. In some examples, the solution further comprises up to 100 wt. %water.

After the sample is mixed with the solution, the presence or absence of a color rection is detected in the solution at step 214. A color reaction indicates the presence of organic matter or non-organic soil in the liquid sample that was tested. The absence of a color reaction indicates the absence of organic matter or non-organic soil in the liquid sample. If there is organic matter or non-organic in the liquid sample, the source of liquid may be cleaned or replaced to remove the organic matter or non-organic soil at step 216. The cleaning may comprise removing the organic matter or non-organic soil by oxidizing, absorbing, using biochemical treatments, diluting, filtering, membrane filtering, treating, sterilizing with UV, applying an antimicrobial agent, combinations thereof, or any other suitable method of cleaning known in the art. In some examples, the source of liquid may need to be replaced instead of cleaning to remove the organic matter or non-organic soil. The method can be repeated until no color reaction is detected after cleaning the source of liquid, meaning that the organic matter or non-organic soil has successfully been removed. In some examples, the method is repeated until the level of organic matter or non-organic soil is below a threshold value for acceptable soil.

In some examples, the solution used for testing is not added directly to the source of liquid. A sample of the source of liquid is removed from the source of liquid and mixed with the solution for testing, which prevents contamination of the source of liquid with the solution. This may be beneficial for large quantities of liquid, such as a large tank of deionized water, where a small sample may be removed for testing without adding anything to the entire source of liquid.

The solution comprises varying amounts of each component. In some examples, the alkali metal hydroxide is present in the solution from about 0.1 wt. %to about 45 wt. %. The alkali hydroxide may be present in the solution from about 0.1 wt. %to about 40 wt. %, from about 0.1 wt. %to about 35 wt. %, from about 0.1 wt. %to about 30 wt. %, from about 0.1 wt. %to about 25 wt. %, from about 0.1 wt. %to about 20 wt. %, from about 0.1 wt. %to about 15 wt. %, from about 0.1 wt. %to about 10 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.1 wt. %to about 2 wt. %, from about 0.1 wt. %to about 1 wt. %, from about 0.5 wt. %to about 45 wt. %, from about 1 wt. %to about 45 wt. %, from about 2 wt. %to about 45 wt. %, from about 5 wt. %to about 45 wt. %, from about 10 wt. %to about 45 wt. %, from about 15 wt. %to about 45 wt. %, from about 20 wt. %to about 45 wt. %, from about 25 wt. %to about 45 wt. %, from about 30 wt. %to about 45 wt. %, from about 35 wt. %to about 45 wt. %, or from about 40 wt. %to about 45 wt. %.

In some examples, the one or more oxidizing compounds is present in the solution from about 0.1 wt. %to about 40 wt. %. The one or more oxidizing compounds may be present in the solution from about 0.1 wt. %to about 35 wt. %, from about 0.1 wt. %to about 30 wt. %, from about 0.1 wt. %to about 25 wt. %, from about 0.1 wt. %to about 20 wt. %, from about 0.1 wt. %to about 15 wt. %, from about 0.1 wt. %to about 10 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.1 wt. %to about 2 wt. %, from about 0.1 wt. %to about 1 wt. %, from about 0.5 wt. %to about 40 wt. %, from about 1 wt. %to about 40 wt. %, from about 2 wt. %to about 40 wt. %, from about 5 wt. %to about 40 wt. %, from about 10 wt. %to about 40 wt. %, from about 15 wt. %to about 40 wt. %, from about 20 wt. %to about 40 wt. %, from about 25 wt. %to about 40 wt. %, from about 30 wt. %to about 40 wt. %, or from about 35 wt. %to about 40 wt. %.

In some examples, the one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate is present in the solution from about 0.001 wt. %to about 5 wt. %. The one or more compounds may be present in the solution from about 0.001 wt. %to about 4. 5 wt. %, from about 0.001 wt. %to about 4 wt. %, from about 0.001 wt. %to about 3.5 wt. %, from about 0.001 wt. %to about 3 wt. %, from about 0.001 wt. %to about 2.5 wt. %, from about 0.001 wt. %to about 2 wt. %, from about 0.001 wt. %to about 1.5 wt. %, from about 0.001 wt. %to about 1 wt. %, from about 0.001 wt. %to about 0.5 wt. %, from about 0.001 wt. %to about 0.1 wt. %, from about 0.001 wt. %to about 0.01 wt. %, from about 0.01 wt. %to about 5 wt. %, from about 0.1 wt. %to about 5 wt. %, from about 0.5 wt. %to about 5 wt. %, from about 1 wt. %to about 5 wt. %, from about 1.5 wt. %to about 5 wt. %, from about 2 wt. %to about 5 wt. %, from about 2.5 wt. %to about 5 wt. %, from about 3 wt. %to about 5 wt. %, from about 3.5 wt. %to about 5 wt. %, from about 4 wt. %to about 5 wt. %, or from about 4.5 wt. %to about 5 wt. %

In some examples, the potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof are present in the solution from about 0.01 wt. %to about 6 wt. %. The potassium tripolyphosphate, sodium tripolyphosphate, other tripolyphosphates, or combinations thereof may be present in the solution from about 0.01 wt. %to about 5.5 wt. %, from about 0.01 wt. %to about 5 wt. %, from about 0.01 wt. %to about 4.5 wt. %, from about 0.01 wt. %to about 4 wt. %, from about 0.01 wt. %to about 3. 5 wt. %, from about 0.01 wt. %to about 3 wt. %, from about 0.01 wt. %to about 2.5 wt. %, from about 0.01 wt. %to about 2 wt. %, from about 0.01 wt. %to about 1.5 wt. %, from about 0.01 wt. %to about 1 wt. %, from about 0.01 wt. %to about 0.5 wt. %, from about 0.01 wt. %to about 0.1 wt. %, from about 0.1 wt. %to about 6 wt. %, from about 0.5 wt. %to about 6 wt. %, from about 1 wt. %to about 6 wt. %, from about 1.5 wt. %to about 6 wt. %, from about 2 wt. %to about 6 wt. %, from about 2.5 wt. %to about 6 wt. %, from about 3 wt. %to about 6 wt. %, from about 3.5 wt. %to about 6 wt. %, from about 4 wt. %to about 6 wt. %, from about 4.5 wt. %to about 6 wt. %, from about 5 wt. %to about 6 wt. %, or from about 5.5 wt. %to about 6 wt. %.

The solution can be prepared by combining the components into a concentrate solution. In some examples, the concentrate solution is used as the test solution to perform the method with no dilution. In other examples, the concentrate solution is diluted to an about 1%to an about 20%use solution. In some examples, the concentrate solution is diluted to an about 4%use solution.

In some examples, the solution may have a pH from about 9.5 to about 13.5. In some examples, the solution may have a pH from about 9.5 to about 13, from about 9.5 to about 12, from about 9.5 to about 11, from about 9.5 to about 10, from about 10 to about 13.5, from about 11 to about 13.5, or from about 12 to about 13.5.

When the solution and the sample of the liquid are mixed, if there is organic matter or non-organic soil present, a color reaction occurs. The color reaction will depend on the components included in the solution. For example, if the solution comprises potassium permanganate, sodium permanganate, or another permanganate compound, the solution may be a purple color before the solution contacts the liquid sample with organic matter or non-organic soil. If the permanganate-containing solution contacts a liquid sample with organic matter or non-organic soil, a color reaction occurs that changes the purple color to a green or yellow color. In other examples, if the solution comprises dichromate, the solution will be orange prior to contacting the liquid sample. If the dichromate-containing solution contacts a liquid sample with organic matter or non-organic soil, a color reaction occurs that changes the orange solution to green.

In some examples, this color reaction occurs in less than 30 minutes, in less than 20 minutes, in less than 10 minutes, in less than 5 minutes, in less than 1 minute, in less than 30 seconds. In some examples, the color reaction is observed at temperatures from about 10 ℃ to about 60 ℃. In some examples, the color reaction is observed at from about 10 ℃ to about 55 ℃, from about 10 ℃ to about 50 ℃, from about 10 ℃ to about 45 ℃, from about 10 ℃ to about 40 ℃, from about 10 ℃ to about 35 ℃, from about 10 ℃ to about 30 ℃, from about 10 ℃ to about 25 ℃, from about 10 ℃ to about 20 ℃, from about 10 ℃ to about 15 ℃, from about 15 ℃ to about 60 ℃, from about 20 ℃ to about 60 ℃, from about 25 ℃to about 60 ℃, from about 30 ℃ to about 60 ℃, from about 35 ℃ to about 60 ℃, from about 40 ℃ to about 60 ℃, from about 45 ℃ to about 60 ℃, from about 50 ℃ to about 60 ℃, or from about 55 ℃ to about 60 ℃. In some examples, the color reaction is observed at room temperature, which is about 15 ℃ to about 25 ℃.

In some examples, the color reaction is observed visually by eye. In other examples, the color reaction may be observed using an instrument such as a color comparator or colorimeter. The color comparator or colorimeter may measure the color change by evaluating the wavelength of the light produced on the visible light spectrum. In some examples, the color reaction is measured between about 400 nm and about 700 nm. The color comparator or colorimeter, or any other instrument suitable of reading absorbance wavelengths, may detect the color reaction and measure the absorbance of the color after the color reaction. In some examples, a control sample of the solution may be measured by the instrument and compared to the solution after the color reaction. The absorbance after the coloration and/or the change in color may be evaluated using digital images or graphical analysis. In some examples, software or a computer program associated with the instrument may measure the change in absorbance before and after the color reaction. In some examples, the instrument may be a portable instrument capable of being used by the ordinary user, such as by cleaning staff or technicians.

In some examples, the method 200 of testing liquid for organic matter or non-organic soil uses a solution that consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof. In some examples, the solution consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, and combinations thereof. In some examples, the solution consists essentially of alkali metal hydroxide, one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and one or more compounds selected from the group consisting of potassium dichromate, sodium dichromate, and combinations thereof.

The above-described method may be used in a CIP system or a COP system, or any of the settings described above. In some examples, the method is particularly used to test the source of liquid for organic matter or non-organic soil before the liquid is used in a sterile setting. For example, the source of liquid may be deionized water used for laboratory testing that cannot have any organic matter or non-organic soil or other contaminants. In some examples, the source of liquid is water or saline to be used in a hospital or clinical setting. In some examples, the source of liquid is water or saline to be used in the preparation of pharmaceuticals or to be used in medical operations. In some examples, the source of liquid is a beverage that is prone to contamination, bacterial growth, or other soils that can cause food-borne illnesses, such as dairy products or brewing products.

The above-described methods may be used in CIP or COP cleaning settings to quickly validate if a surface has been sufficiently cleaned to remove organic matter or non-organic soil. The methods may be used with an instrument that measures the absorbance of a color reaction produced using the solutions described herein. A user of the methods may adapt the method for a particular industry and set thresholds for acceptable absorbance readings that correlate to the presence of organic matter or non-organic soil. For example, a user in the beverage industry might determine that a certain level of organic matter or non-organic soil is acceptable in their CIP or COP system and calibrate an instrument to measure absorbance over a particular value and alert the user that the amount of organic matter exceeds the threshold of acceptable matter. In another example, a user in the pharmaceutical industry or a user producing saline might determine that no organic matter or non-organic soil is acceptable in their CIP or COP system and calibrate an instrument to a sensitivity that will measure absorbance and detect any increases in absorbance over a base level. The methods and kits described herein are contemplated to be used to set allowable thresholds of organic matter or non-organic soil depending on the industry and user.

In some examples, the threshold of acceptable absorbance readings may correspond to up to 0 ppm of soil, up to 10 ppm of soil, up to 50 ppm of soil, up to 100 ppm of soil, up to 500 ppm of soil, up to 1,000 ppm of soil, or up to 10,000 ppm of soil. These thresholds indicate that a surface or solution to be tested is considered clean if the soil level is at or below the threshold level. If the soil exceeds the threshold value, the surface or solution is not considered clean. For example, a pharmaceutical plant may set a threshold of acceptable soil at 0 ppm to maintain sterile conditions for medications, while a food and beverage plant may have a threshold level of 1,000 ppm of soil, or perhaps no threshold of soil. In some examples, the threshold may also refer to a visual check to compare a swab taken from a clean surface to a swab taken from a surface to be tested to see if there is a visual change on the swab.

Also described herein are kits including the above-described components to perform the methods disclosed herein. In some examples, the kit includes a substrate, such as a swab, absorbent ball, wipe, test paper, or other suitable substrate. The kit may also include a solution for detecting the presence of organic matter or non-organic soil. In some examples, the solution is the same solution as described above for the methods described herein. The kit may also include a test container configured to hold the solution, such as a beaker, an aliquot tube, a sample card, or any other suitable container. The container is configured to hold the solution wherein the substrate, such as the absorbent ball, wipe, or test paper, contacts the solution. The color reaction may occur in the solution in the test container or on the substrate. The details described above with respect to the methods apply to the kit for testing for organic matter or non-organic soil. The kit is intended for use to perform the methods described above.

The following non-limiting Examples are provided as illustrative embodiments of the invention. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical values, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements. The Examples are illustrative and may only show limited numerical quantities of the components described above. Only some Examples are shown for the sake of brevity, but the full quantity ranges of components described above are contemplated.

EXAMPLES

Example 1: Preparation of Use Solution

The method of quick cleaning validation described herein is used to test for the presence of organic matter or non-organic soil in a CIP or COP system. In this Example, a solution was prepared by combining the components described below in Table 1. The solution in Table 1 was prepared to form a concentrate solution. The concentrate solution was diluted to a 4%use solution before use.

TABLE 1: Preparation of Test Solution.

Example 2: Testing of Milk Samples

Ten 500 mL beakers were filled with 100 mL of the use solution from Example 1. One beaker was untreated as a blank sample to compare other samples against. The nine remaining beakers each had whole milk added to them in increasing quantities of 10 ppm, 20 ppm, 30 ppm, 40 ppm, 50 ppm, 100 ppm, 500 ppm, 1000 ppm, and 10,000 ppm. The control beaker and the nine test beakers were lined up in order of increasing concentration from right to left and photographed for visual observation of the color reaction after 20 minutes, and a schematic of the results in beakers with 10 ppm, 20 ppm, 30 ppm, 40 ppm, 50 ppm, 100 ppm, 1000 ppm, and 10,000 ppm is shown in FIG. 3B. The control sample retained its initial purple color, and milk at concentrations of 10-100 ppm showed minimal changes in the purple hue with visual observation. The beakers with 1000 ppm and 10,000 ppm milk show a color reaction from the initial purple color of the use solution to hues of green. The beakers were again observed after 60 minutes to evaluate for further color changes in the color reaction.

10 mL of each solution was transferred into a 10 mL vial, and the absorbance of each solution was read with a HACH DR 890 portable colorimeter instrument using program #41. The program is used to detect dissolved manganese in solution and provides absorbance readings compared to the control sample with 0 ppm milk. Table 2 shows the absorbance readings with the HACH DR 890 for each of the ten vials after 20 minutes and after 60 minutes. For concentrations of milk greater than 100 ppm, a color change was visually observable, and a measurement using a colorimeter was not necessary to observe the presence of milk. At concentrations of 100 ppm or below, a colorimeter was beneficial for measuring the presence of milk that was not visually observable. Using the colorimeter, the absorbance readings changed relative to the control sample, which indicated the presence of milk. Colorimeter readings may be impacted by milk turbidity at concentrations above 100 ppm, so visual observation may be preferred in some instances.

TABLE 2: HACH DR 890 absorbance reading

The samples were also measured using a desktop Shimadzu UV-3101PC UV-VIS-NIR spectrophotometer. The color was measured at various wavelengths from 400 nm to 700 nm after 20 minutes and after 60 minutes. FIG. 4A shows the absorption for all nine samples with 0-10,000 ppm of milk measured at 20 minutes and 60 minutes for wavelengths between 280 and 700 nm. FIG. 4B shows a plot of absorbance for samples including 0 ppm, 10 ppm, and 50 ppm of milk measured at wavelengths of 400-700 nm after 20 minutes. When the concentration of milk is below 100 ppm, absorbance decreased in the range of 480 nm to 570 nm, but when milk concentration increases above 100 ppm, an increase in absorbance was measured at both 480-570 nm and 580-700 nm.

FIG. 4C shows the absorbance at 528 nm and 620 nm for milk concentrations of 0 ppm to 1000 ppm. The plot shows a linear relationship between absorbance and concentration of milk at concentrations below 100 ppm. This is beneficial because often concentrations of milk, or other organic matter or non-organic soil, do not produce visually observable results at concentrations below 100 pm.

FIG. 4D shows a measurement of absorbance at 400 nm to 700 nm for a sample with 50 ppm of milk measured at 20 minutes and at 60 minutes. The absorbance in a single sample varies over various wavelengths and over time. The absorbance for the sample after 20 minutes varied from the absorbance measured after 60 minutes at almost all absorbance values. Thus, an absorbance reading should be read at the same time period elapsed for all samples to be tested, including the blank control used for comparison.

Example 3: Testing of Tea Samples

The use solution in Example 1 and the method of Example 2 were used to test the color reaction for various concentrations of black tea powder using the methods and solutions described herein. Nine 500 mL beakers were filled with 100 mL of use solution and included the following amounts of black tea powder: 0 ppm, 10 ppm, 20 ppm, 30 ppm, 40 ppm, 50 ppm, 100 ppm, 500 ppm, and 1000 ppm. The absorbance for each sample was measured at 20 minutes from the start of the color reaction (i.e., when the black tea powder was added to the use solution) using a Shimadzu UV-3101PC UV-VIS-NIR spectrophotometer, as well as the absorbance at 60 minutes for 10 ppm, 20 ppm, 30 ppm, 40 ppm, and 50 ppm for wavelengths 400-700 nm, which is shown in FIG. 5A. FIG. 5B shows the absorbance for samples with 0 ppm, 10 ppm, 50 ppm, and 100 ppm measured at 400 nm to 700 nm after 20 minutes. FIG. 5C shows the absorbance at 528 nm and 620 nm for black tea concentrations of 0 ppm to 100 ppm. The results show that the preferred measurement conditions were at wavelength ranges 470-520 nm and 570-650 nm, after 20 minutes, and at room temperature.

Example 4: Field Swab Test

Equipment from a tea processing facility was disassembled after a CIP cleaning protocol was performed. The equipment was swabbed to test for the presence of organic matter and non-organic soil. The swab was evaluated using the compositions, solutions, and methods described herein. An identical swab sample taken from the equipment was evaluated using an ATP test at the same time. The results of each test are shown in Table 3.

TABLE 3: Comparison of described compositions and methods with ATP testing

The results of the comparison demonstrate that the compositions, solutions, and methods described herein provide 1) an observable a color change and 2) a change in absorbance that can be measured to detect and identify the presence of organic matter and/or non-organic soil.

Additionally, in an ATP test, the swab was swiped on a surface to sample it for soil, and after 20 minutes, the reading of the swab was 0 RLU. A measurement of 0 RLU indicates that there is no soil on the surface because no RLUs were detected. However, a swab of the same surface that was tested under the same conditions using the compositions, solutions, and methods described herein produced a reading as measured by the HACH DR890 that differed from the reading of the blank control, indicating that there is soil on the surface. Therefore, the compositions, solutions, and methods described herein detect the presence of soil that an ATP test does not detect.

Additionally, the reaction produced by the compositions, solutions, and methods described herein can be used to calculate a threshold percentage, where the absorbance reading of a sample are divided by the absorbance reading of a blank control sample. This is helpful if there are low concentrations of soil and thus a minimally visible color change, or no visual color change, produced, because the threshold percentage provides an objective value to compare samples against. For example, an end user in the field may set a threshold for an acceptable amount of soil in CIP equipment used in a food and beverage processing facility. The absorbance of samples taken from the CIP equipment may be measured and compared against the threshold to determine if there is soil present, and if so, if the amount of soil falls below the threshold value. The threshold value may vary for different industries where varying levels of soil may be acceptable or not acceptable.

Having described the preferred aspects and implementations of the present disclosure, modifications and equivalents of the disclosed concepts may readily occur to one skilled in the art. However, it is intended that such modifications and equivalents be included within the scope of the claims which are appended hereto.

Claims

A method of testing a surface for organic matter or non-organic soil, comprising:

(a) wiping a surface with a substrate;

(b) contacting the substrate with a solution comprising:

(i) alkali metal hydroxide,

(ii) one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and

(iii) one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof; and

(c) detecting a color reaction on the substrate or in the solution.
The method of claim 1, wherein the solution further comprises potassium tripolyphosphate or sodium tripolyphosphate.
The method of claims 1 or 2, wherein detecting a color reaction indicates the presence of organic matter or non-organic soil on the surface.
The method of any of claims 1-3, further comprising step (d) cleaning the surface to remove the organic matter or non-organic soil.
The method of claim 4, wherein cleaning the surface comprises wiping, spraying, soaking, treating with UV sterilization, or combinations thereof.
The method of any of claims 4-5, further comprising repeating steps (a) through (d) until no color reaction detected.
The method of any of claims 1-6, the solution comprising:

(a) 0.1 to 45 wt. %alkali metal hydroxide,

(b) 0.1 to 40 wt. %of the one or more oxidizing compounds, and

(c) 0.001 to 5 wt. %potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, or combinations thereof.
The method of any of claims 1-7, the solution comprising about 0.01 wt. %to about 6 wt. %of sodium tripolyphosphate or potassium tripolyphosphate.
The method of any of claims 1-8, wherein the solution further comprises up to 100 wt. %water.
The method of any of claims 1-9, wherein the color reaction is detected visually.
The method of any of claims 1-9, wherein the color reaction is measured by a color comparator or colorimeter.
The method of any of claims 1-11, wherein the solution is diluted to an about 1%to an about 20%use solution before the solution contacts the substrate.
The method of any of claims 1-12, wherein the solution does not contact the surface and does not need to be rinsed off after testing.
The method of any of claims 1-13, wherein the surface is part of a clean-in-place (CIP) system or a clean-out-of-place (COP) system.
The method of claim 14, wherein the CIP system is in a food plant, beverage plant, or pharmaceutical plant.
The method of any of claims 1-15, wherein the surface is in a hospital, a kitchen, a hotel, a laboratory, or an office.
The method of any of claims 1-16, wherein the pH of the solution is from about 9.5 to about 13.5.
The method of any of claims 1-17, wherein the color reaction produces a color change when organic matter or non-organic soil is present.
The method of claim 18, wherein the color change is a change in absorbance units of 0.1 or more.
The method of any of claims 1-19, wherein the color rection occurs in less than 30 minutes.
The method of any of claims 1-20, wherein the color reaction occurs in less than 20 minutes.
The method of any of claims 1-21, wherein the color reaction is observed at room temperature.
The method of any of claims 1-22, wherein the color reaction is observed at from about 10 ℃ to about 60 ℃.
The method of any of claims 1-23, wherein the color comparator measures the color reaction at 400 nm to 700 nm.
A method of testing liquid for organic matter or non-organic soil, comprising:

(a) taking a sample of a source of liquid;

(b) mixing the sample and a solution, the solution comprising:

(i) alkali metal hydroxide,

(ii) one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and

(iii) one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, and combinations thereof; and

(c) detecting a color reaction in the solution.
The method of claim 25, wherein the solution further comprises potassium tripolyphosphate or sodium tripolyphosphate.
The method of any of claims 25-26, wherein detecting a color reaction indicates the presence of organic matter or non-organic soil in the source of water.
The method of any of claims 25-27, further comprising step (d) cleaning the source of liquid to remove the organic matter or non-organic soil.
The method of claim 28, wherein cleaning the source of liquid comprises oxidizing, absorbing, biochemical treatment, diluting, filtering, membrane filtering, treating, sterilizing with UV, or combinations thereof.
The method of any of claims 28-29, further comprising repeating steps (a) through (d) until no color reaction detected.
The method of any of claims 25-30, the solution comprising:

(a) 0.1 to 45 wt. %alkali metal hydroxide,

(b) 0.1 to 40 wt. %of the one or more oxidizing compounds, and

(c) 0.001 to 5 wt. %potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, or combinations thereof.
The method of any of claims 25-31, the solution comprising about 0.01 wt. %to about wt. %of sodium tripolyphosphate or potassium tripolyphosphate.
The method of any of claims 25-32, wherein the solution further comprises up to 100 wt. %water.
The method of any of claims 25-33, wherein the color reaction is detected visually.
The method of any of claims 25-33, wherein the color reaction is measured by a color comparator or colorimeter.
The method of any of claims 25-35, wherein the solution is diluted to an about 1%to an about 20%use solution before the solution contacts the sample.
The method of any of claims 25-36, wherein the pH of the solution is from about 9. 5 to about 13.5.
The method of any of claims 25-37, wherein the solution is not added to the source of liquid.
The method of any of claims 25-38, wherein the liquid is water used for saline, pharmaceuticals, laboratory reagents, medical operations, food or beverage preparation, or used for cleaning or rinsing.
The method of any of claims 25-39, wherein the color rection occurs in less than 30 minutes.
The method of any of claims 25-40, wherein the color reaction occurs in less than 20 minutes.
The method of any of claims 25-41, wherein the color reaction is observed at room temperature.
The method of any of claims 25-42, wherein the color reaction is observed at from about 10 ℃ to about 60 ℃.
The method of any of claims 25-43, wherein the color reaction produces a color change when organic matter or non-organic soil is present.
The method of claim 44, wherein the color change is a change in absorbance units of 0.1 or more.
The method of claim 36, wherein the color comparator or colorimeter measures the color reaction at 400 nm to 700 nm.
A kit for testing for organic matter or non-organic soil, comprising:

a swab, absorbent ball, wipe, or test paper;

a solution for detecting the presence of organic matter or non-organic soil comprising:

alkali metal hydroxide,

one or more oxidizing compounds comprising sodium hypochlorite, potassium hypochlorite, sodium persulfate, potassium persulfate, or monopersulfate, and

one or more compounds selected from the group consisting of potassium permanganate, sodium permanganate, potassium dichromate, and sodium dichromate; and

a test container configured to hold the solution, wherein the swab, absorbent ball, wipe, or test paper contacts the solution.
The kit of claim 47, wherein the swab, absorbent ball, wipe, or test paper is contacted with a surface or source of liquid to be tested for organic matter or non-organic soil before contacting the solution.
The kit of any of claims 47-48, wherein a color reaction will occur in the solution if organic matter or non-organic soil is present.
The kit of any of claims 47-49, wherein the solution further comprises up to 100 wt. %water.
The kit of any of claims 47-50, the solution comprising:

(a) 0.1 to 45 wt. %alkali metal hydroxide,

(b) 0.1 to 40 wt. %of the one or more oxidizing compounds, and

(c) 0.001 to 5 wt. %potassium permanganate, sodium permanganate, potassium dichromate, sodium dichromate, or combinations thereof.
The kit of any of claims 47-51, wherein the solution is visually observed for a color reaction after the swab, absorbent ball, wipe, or test paper is dipped or soaked in the solution.
The kit of any of claims 47-51, wherein the solution is measured for a color reaction in an instrument after the swab, absorbent ball, wipe, or test paper is dipped or soaked in the solution.
The kit of any of claims 47-53, wherein the pH of the solution is from about 9.5 to about 13.5.
The kit of any of claims 47-54, wherein the kit is used on a surface of a clean-in-place (CIP) system or a clean-out-of-place (COP) system.
The kit of claim 55, wherein the CIP system is in a food plant, beverage plant, or pharmaceutical plant.
The kit of any of claims 47-55, wherein the kit is used in a hospital, a kitchen, a hotel, a laboratory, or an office.
The kit of any of claims 47-57, wherein the color rection occurs in less than 30 minutes.
The kit of any of claims 47-58, wherein the color reaction occurs in less than 20 minutes.
The kit of any of claims 47-59, wherein the color reaction is observed at room temperature.
The kit of any of claims 47-60, wherein the color reaction is observed at from about 10 ℃ to about 60 ℃.
The kit of any of claims 47-61, wherein the kit is used to test a source of liquid.
The kit of claim 62, wherein the liquid is water used for saline, pharmaceuticals, laboratory reagents, medical operations, food or beverage preparation, or used for cleaning or rinsing.
The kit of any of claims 47-63, wherein the color reaction produces a color change when organic matter or non-organic soil is present.
The kit of claim 64, wherein the color change is a change in absorbance units of 0.1 or more.
The kit of any of claims 47-65, wherein the color reaction is detected visually.
The kit of any of claims 47-65, wherein the color reaction is measured by a color comparator or colorimeter.
The kit of any of claims 47-67, wherein the solution is diluted to an about 1%to an about 20%use solution before the solution contacts the swab, absorbent ball, wipe, or test paper.
The kit of claim 67, wherein the instrument is a color comparator or colorimeter that measures the color reaction at 400 nm to 700 nm.