CN111533817A - Production process of hydroxypropyl distarch phosphate - Google Patents

Abstract

The invention discloses a production process of hydroxypropyl distarch phosphate, comprising the following steps: (1) mixing native starch and water to prepare starch milk; (2) adding or adding to the starch milk in step (1). Add potassium hydroxide solution dropwise to adjust pH; (3) add propylene oxide, at 40～45℃, react for 18～22h; (4) add sodium trimetaphosphate or phosphorus oxychloride and react for 3～8h, wash and dehydrate , and drying to obtain the hydroxypropyl distarch phosphate. The production process of the hydroxypropyl distarch phosphate of the present invention utilizes potassium hydroxide solution to adjust the pH of the reaction system, does not need to add salts such as sodium sulfate and sodium chloride as swelling inhibitors, and solves the problem that the washing process produces a large amount of difficult to handle high Technical difficulties in the production of salt wastewater.

Description

A kind of production technology of hydroxypropyl distarch phosphate

technical field

The invention relates to a preparation method of modified starch, in particular to a production process of hydroxypropyl distarch phosphate.

Background technique

Hydroxypropyl distarch phosphate is a product obtained by reacting raw starch with cross-linking agents such as propylene oxide, sodium trimetaphosphate or phosphorus oxychloride under alkaline conditions. The production medium of hydroxypropyl distarch phosphate includes alcoholic aqueous solution, alcoholic solution and aqueous solution. Aqueous alcohol solution and alcohol as medium require high production equipment and reaction conditions, which are not easy to be industrialized, and the storage of alcohol poses a safety hazard for factories. The commonly used basic catalyst for the production of water-based hydroxypropyl distarch phosphate is sodium hydroxide. Adding a certain concentration of sodium hydroxide solution to adjust the pH value of the reaction system, as the pH value increases, the starch granules swell (gelatinization after severe swelling), increase the consistency of the starch milk in the reaction system, and affect the starch reaction, washing, dehydration, etc. Subsequent processes reduce product quality. In order to prevent starch from swelling and gelatinizing, a certain amount of salt (sodium sulfate or sodium chloride) is generally added as a swelling inhibitor. The inhibitor itself does not participate in the reaction, and the addition ratio is adjusted according to the addition amount of propylene oxide. Under normal conditions, the amount of sodium sulfate added is 8-30% by weight of starch. In the washing process, it takes 6-10 times the weight of starch to wash sodium sulfate, resulting in a large amount of high salt water that is difficult to handle. The cost of aerobic aeration is used for treatment, and the treatment is difficult and the equipment investment cost is high.

SUMMARY OF THE INVENTION

The object of the present invention is to overcome the deficiencies existing in the prior art and provide a production process of hydroxypropyl distarch phosphate.

In order to achieve the above object, the technical scheme adopted in the present invention is: a production technique of hydroxypropyl distarch phosphate, comprising the following steps:

(1) raw starch and water are mixed and formulated into starch milk;

(2) in the starch milk described in step (1), adding or dripping potassium hydroxide solution to adjust pH is 10-14;

(3) adding propylene oxide, and reacting at 40～45°C for 18～22h;

(4) adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 hours, washing, dehydrating and drying to obtain the hydroxypropyl distarch phosphate.

The production process of hydroxypropyl distarch phosphate of the present invention utilizes the method of stream addition or dropwise addition of potassium hydroxide solution to adjust the pH of the reaction system, and does not need to add salts such as sodium sulfate and sodium chloride as swelling inhibitors. It solves the production technical problem that the washing process produces a large amount of difficult-to-treat high-salt wastewater.

In step (1), starch milk represents a mixture of native starch and water.

Preferably, in step (1), the mass concentration of the starch milk is 30-40%, and controlling the starch milk to this concentration can effectively control the reaction efficiency of the system and the stability of the reaction process.

Preferably, in step (2), the adding time of the potassium hydroxide solution is at least 3h.

Preferably, in step (2), the adding time of the potassium hydroxide solution is 3-5h. The inventor found that when the addition time of potassium hydroxide solution is less than 3h, there is a certain degree of swelling, and when the addition time is extended to at least 3h, the starch swelling can be suppressed, but too long addition time easily leads to low production efficiency.

Preferably, the mass concentration of the potassium hydroxide solution is 3-9%. The addition amount of potassium hydroxide is determined by the pH of the reaction system, and in order to control the time of addition, the potassium hydroxide solution of the above-mentioned mass concentration is preferably used.

Preferably, in step (4), the pH after adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 hours is 3-5.

Preferably, in step (3), the added amount of the propylene oxide is 3-10% of the starch quality.

Preferably, the native starch is at least one of tapioca starch, waxy corn starch and potato starch, but not limited to the above types.

The beneficial effects of the present invention are as follows: the present invention provides a production process of hydroxypropyl distarch phosphate, and the production process of hydroxypropyl distarch phosphate of the present invention utilizes the mode of stream addition or dropwise addition of potassium hydroxide solution The pH of the reaction system is adjusted without the need to add salts such as sodium sulfate and sodium chloride as swelling inhibitors, which solves the production technical problem that a large amount of difficult-to-treat high-salt wastewater is generated in the washing process. At the same time, the hydroxypropyl distarch phosphate product obtained according to the preparation process of the present invention has the characteristics of moderate viscosity, strong water retention capacity, acid and alkali resistance, mechanical processing resistance, smooth taste and the like, and conforms to the GB29931-2013 standard; The obtained modified starch can be used in yogurt, sauce and other foods, and has the effects of thickening, water retention and freeze-thaw resistance.

Detailed ways

In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below with reference to specific embodiments.

Example 1

An embodiment of the production process of hydroxypropyl distarch phosphate according to the present invention, the production process of hydroxypropyl distarch phosphate in this embodiment comprises the following steps:

Weigh 5kg of waxy corn starch (moisture content 13%), prepare it into 35% starch milk with mass concentration, detect initial pH value and degree of Baume, and add potassium hydroxide solution with mass concentration of 5% in 5h to make the solution. The pH of starch milk is 12, add 8% starch mass propylene oxide, heat up to 45 ° C, and keep the reaction for 22h, add 0.05% starch mass sodium trimetaphosphate, and then conduct cross-linking reaction for 4h, neutralize the pH to 5.0, and use starch The hydroxypropyl distarch phosphate is obtained by washing with 1 times the weight of water, dehydration, drying, and packaging, and the product is subjected to index detection.

Example 2

An embodiment of the production process of hydroxypropyl distarch phosphate according to the present invention, the production process of hydroxypropyl distarch phosphate in this embodiment comprises the following steps:

Weigh 5kg of waxy corn starch (moisture content 13%), prepare it into 35% starch milk by mass concentration, detect initial pH value and degree of Baume, add potassium hydroxide solution with mass concentration of 7% in 4h to make the solution. The pH of starch milk is 12, add 8% starch mass propylene oxide, heat up to 45 ° C, and keep the reaction for 22h, add 0.05% starch mass sodium trimetaphosphate, and then conduct cross-linking reaction for 4h, neutralize the pH to 5.0, and use starch The hydroxypropyl distarch phosphate is obtained by washing with 1 times the weight of water, dehydration, drying, and packaging, and the product is subjected to index detection.

Example 3

An embodiment of the production process of hydroxypropyl distarch phosphate according to the present invention, the production process of hydroxypropyl distarch phosphate in this embodiment comprises the following steps:

Weigh 5kg of waxy corn starch (moisture content 13%), prepare it into 35% starch milk by mass concentration, detect initial pH value and degree of Baume, add potassium hydroxide solution with mass concentration of 9% in 3h to make the solution. The pH of starch milk is 12, add 8% starch mass propylene oxide, heat up to 45 ° C, and keep the reaction for 22h, add 0.05% starch mass sodium trimetaphosphate, and then conduct cross-linking reaction for 4h, neutralize the pH to 5.0, and use starch The hydroxypropyl distarch phosphate is obtained by washing with 1 times the weight of water, dehydration, drying, and packaging, and the product is subjected to index detection.

Comparative Example 1

A kind of comparative example of the production technique of hydroxypropyl distarch phosphate of the present invention, the production technique of hydroxypropyl distarch phosphate described in this comparative example comprises the following steps:

Weighing 5kg of waxy corn starch (moisture content 13%), mix it into 35% starch milk with mass concentration, detect initial pH value and degree of Baume, add the dilute sodium hydroxide solution with mass concentration of 5% in 5h, The pH of the starch milk was made 12. Due to the starch gelatinization in the process of feeding sodium hydroxide solution, the gelatinized starch cannot undergo the etherification reaction of propylene oxide.

Comparative Example 2

A kind of comparative example of the production technique of hydroxypropyl distarch phosphate of the present invention, the production technique of hydroxypropyl distarch phosphate described in this comparative example comprises the following steps:

Weigh 5kg of waxy corn starch (moisture content 13%), add 1.0kg of sodium sulfate, and add water to prepare starch milk with a mass concentration of 35%, detect initial pH value and degree of Baume, add a certain amount of 4% in 5h The pH of the starch milk is 12, add 8% starch mass propylene oxide, heat up to 45 °C, keep the reaction for 22h, add 0.05% starch mass sodium trimetaphosphate, and then proceed to cross-linking reaction for 4h , after neutralizing the pH to 5.0, washing with 8 times the weight of starch with water, dehydration, drying, and packaging to obtain hydroxypropyl distarch phosphate, and the product is subjected to index detection.

Example 4

In order to explore the influence of the feeding time length of potassium hydroxide solution on the degree of expansion, change the feeding time length of different potassium hydroxide solutions in Example 1, the relationship between the expansion degree and the feeding time length of potassium hydroxide solution is shown in the table 1.

Table 1

As can be seen from Table 1, when the feeding time of potassium hydroxide solution is not less than 3h, the degree of swelling can be effectively reduced, but the production efficiency is lower after the feeding time is greater than 5h, and adding sodium hydroxide solution requires adding swelling inhibition agent to achieve the effect of inhibiting swelling.

The peak viscosity, hydroxypropyl content and electrical conductivity of the hydroxypropyl distarch phosphate prepared in Examples 1 to 3 and Comparative Examples 1 to 2 were tested, wherein the peak viscosity was tested with a Brabender viscometer, and the test results are shown in the table 2.

Table 2

As can be seen from Table 2, the hydroxypropyl distarch phosphate of the present invention adopts the adjustment pH value of the potassium hydroxide solution by flow, can not need to add expansion inhibitor, does not produce gelatinization phenomenon, and produces waste water far lower than Comparative Example 2. The hydroxypropyl distarch phosphate product obtained by the preparation process described in Examples 1-3 has the characteristics of moderate viscosity (500-1000BU), strong water retention capacity, acid and alkali resistance, mechanical processing resistance, smooth taste, etc., which conform to GB29931-2013 standard. The modified starch prepared by the process of the invention can be applied to foods such as yogurt and sauce, and has the effects of thickening, water retention and freeze-thaw resistance.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the protection scope of the present invention. Although the present invention is described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that, The technical solutions of the present invention may be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention.

Claims (8)

1. The production process of the hydroxypropyl distarch phosphate is characterized by comprising the following steps:

(1) mixing raw starch and water to prepare starch milk;

(2) adding or dropping a potassium hydroxide solution into the starch milk obtained in the step (1) in a flowing manner to adjust the pH value to 10-14;

(3) adding propylene oxide, and reacting for 18-22 h at 40-45 ℃;

(4) and adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 h, washing, dehydrating and drying to obtain the hydroxypropyl distarch phosphate.

2. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (1), the mass concentration of the starch milk is 30-40%.

3. The process for producing hydroxypropyl distarch phosphate according to claim 1, wherein the potassium hydroxide solution is added in step (2) for a period of at least 3 hours.

4. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (2), the addition time of the potassium hydroxide solution is 3-5 h.

5. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (2), the mass concentration of the potassium hydroxide solution is 3-9%.

6. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (3), the amount of propylene oxide added is 3-10% by mass of the starch.

7. The production process of hydroxypropyl distarch phosphate as claimed in claim 1, wherein in step (4), the pH value after adding sodium trimetaphosphate or phosphorus oxychloride and reacting for 3-8 h is 3-5.

8. The process for producing hydroxypropyl distarch phosphate according to claim 1, wherein the native starch is at least one of tapioca starch, waxy corn starch and potato starch.