WO2013013371A1

WO2013013371A1 - Dried pulp preparation from unprocessed raw materials

Info

Publication number: WO2013013371A1
Application number: PCT/CN2011/077509
Authority: WO
Inventors: Hua Bai; Yong-cheng LIAO; Zhong-wei SUN; Olivier BALLEVER; Qingzhu ZHAO
Original assignee: Nestec SA
Current assignee: Nestec SA
Priority date: 2011-07-22
Filing date: 2011-07-22
Publication date: 2013-01-31
Anticipated expiration: 2014-01-22
Also published as: CN103648301A; WO2013014053A1

Abstract

Dried fruit and vegetable pulp preparation obtained from fresh, unprocessed fruits or vegetables to be added to powdered beverages, cereals, yogurt, ice cream or pet food, wherein the pulp is dried by freeze drying.

Description

Dried pulp preparation from unprocessed raw materials

The present invention relates generally to the field of food and beverages. In particular, the present invention relates to dried fruit and vegetable pulp and to products containing such pulp preparations. One embodiment relates to a dried fruit or vegetable pulp preparation obtained from fresh, unprocessed fruits or vegetables.

Beverages on the basis of fruit juices or fruit flavours are generally well-liked by consumers and are perceived as refreshing, in particular during the warm season, while at the same time they generally are beneficial to the consumer' s health .

Sometimes it is not possible or too expensive to produce such beverages directly from fresh fruits due to seasonal or regional limitation. In such cases, beverages on the basis of fruit juices or fruit flavours are produced from concentrate, e.g. from powdered beverages.

Most of the currently sold natural powered or solid beverage preparations contain fruit powder which fully dissolves after reconstitution in water. Such a fruit powder is often prepared by spray drying. The dissolution of the fruit powder in the beverage has however the consequence that consumers often do not perceive the presence of fruit.

To overcome this, pulp particles may be added to fruit juice preparations. The presence of pulp particles in beverages is considered as pleasant by the consumer as it more closely resembles the mouth feel of freshly squeezed fruit juices, for example. However, the application of dehydrated fruit pulp to powdered beverages to deliver a pulp mouthfeel after reconstitution is not a simple task to accomplish reasons, e.g., due to costs or technical limitations.

Some patent applications have been published in this respect.

For example, US4233334 discloses a dry powdered beverage mix adapted to be reconstituted in cold water. The powdered mix includes beaten cellulose pulp, which imparts an appearance and mouth-feel resembling freshly squeezed natural juice. When preparing the dry powdered beverage mix, the beaten pulp is mixed with sugar, and the pulp/sugar mixture is air dried to form a dry cake which is then crushed to a powder.

Pulp is in particularly perceived as pleasant, if it is visible in the beverage, well hydrated and maintains a floating status in the beverage.

EP0098120B1 addresses the problem that natural citrus pulp often is not easy to rehydrate after drying and hence often clumps and generates particles with a high density. It is suggested to adjust the pH of citrus pulp to at least 4.0 before freeze drying the pulp to a moisture content of less than 10 weight -% and grinding it. This way a dried citrus pulp with improved wetting and dispersion characteristics is obtained .

The presence of sugar particles and pulp particles, e.g. in a powdered beverage composition, has the consequence that the robust and sharp edged sugar particles grind the pulp particles and - consequently - destroy at least in part the pulp structure. Similar friction effects can also be observed in between the pulp particles. This happens in particular during production and transport, but also during storage times Additionally, it is a technical challenge to mix relatively low density pulp with sugar particles to homogeneity during processing. Further segregation could be observed during transportation and storage.

The results are pulp particle segregation, impaired hydration properties, and an impaired mouthfeel of the final product after reconstitution with milk or water.

Consequently, it was the objective of the present invention to produce pulp, e.g., for powdered beverages, that is clearly visible after reconstitution in water, has good rehydration properties, has a pleasant chewy mouthfeel, and a density range that allows that the pulp maintains a floating status.

Ideally, such a pulp should be obtainable by a process with a high freeze drying efficiency for dried pulp resulting in pulp which is less cohesive and caking is avoided.

The present inventors have addressed these needs. They were surprised to see that they could achieve this objective by the subject matter of the independent claims. The dependent claims further develop the idea of the present invention .

In the state of the art dried fruit pulp is usually produced from waste products or by-products of the juice production, e.g. from citrus grain after juice extraction. Oftentimes the grains are dried before they are applied to pulp production.

In contrast, the present inventors were able to demonstrate that dried fruit or vegetable pulp obtained from fresh fruits or vegetables has superior properties compared to pulp obtained from waste products or by-products of the juice production . In addition, using fresh unprocessed fruit or vegetables as pulp source is a commercially very interesting alternative as significantly less fruits or vegetables are needed per kg pulp compared to using waste products or by-products of the juice production as starting material. This has the consequence that using whole unprocessed fruits or vegetables as starting material for pulp production may be more economic.

Remarkably, dried fruit or vegetable pulp obtained from fresh unprocessed fruit or vegetables as starting material provided a much better mouthfeel after reconstitution in water. A unique, very pleasant chewy texture was obtained, which could not be produced with pulp from waste material of juice production .

Without wishing to be bound by theory, the inventors believe that this difference is due to the fact that in pulps obtained from processed fruits or vegetables the texture and structure of the pulp is significantly damaged by the strong squeezing or beating operation.

If unprocessed fruits or vegetables are used for dried pulp production, the fruit or vegetable grain is protected and will not be damaged during pulp production.

Consequently, one embodiment of the present invention is a dried fruit or vegetable pulp preparation obtained from fresh, unprocessed fruits or vegetables .

The dried fruit or vegetable pulp preparation of the present invention may be to be added to powdered beverages, cereals, yogurt, icecream or pet-food.

The powdered beverage may be to be reconstituted in milk or water, for example. Fruits or vegetables are considered "fresh" if they are used within normal consumption times after harvest. These time frames may vary depending on the fruit or vegetable. For example, a fresh fruit is not dried and has a water content corresponding to at least 50%, preferably at least 75% even more preferred at least 90% corresponding to the fruit or vegetable directly after harvest.

Fruits or vegetables are considered "unprocessed" if they are used as such as raw material to prepare pulp and were in particular not treated beforehand to remove the juice prior to pulp collection, for example by squeezing or beating the fruit or vegetable to extract the juice. Typically, the flesh of the fruits or vegetables is used to prepare the pulp. Peeled fruit or vegetables may be considered as unprocessed. A fruit or vegetable pulp preparation is considered dried if it has a water content of below 10 weight-%, below 5 weight-%, or for example below 3 weight-%.

Remarkably, by using fresh unprocessed fruit or vegetables as starting material, a maximum of their nutrients can be retained and their naturality can be best preserved when drying .

Typically, the fruit or vegetable pulp preparation is obtainable - and may be obtained - by a process comprising the steps of separating the pulp from the fruits or vegetables and drying the pulp.

Separating the pulp from the fruit allows removing all constituents of fruits or vegetables that would impart unwanted tastes or properties to the pulp preparation. Oftentimes, for example, the skin of fruits has a somewhat bitter taste. For example, in case of oranges or pomelos or grapefruit or tangerine , the outer skin, membranes and seeds are removed and only the pulp is used for further processing.

Drying allows reducing the water activity and the water content of the pulp allowing easy storing and avoiding decay processes .

The fruit or vegetable pulp may be dried by any method that is known in the art .

For example, the pulp may be dried by, for example, by air drying, freeze draying, roller drying, spray drying, vacuum drying, microwave drying, or combinations thereof.

The inventors have explored several drying techniques and were surprised to see that freeze drying had several advantages compared to other drying techniques.

Freeze dried pulp had excellent visual properties, also after reconstitution, significantly better compared to other drying techniques .

Freeze drying also allowed generating an improved floating status of the pulp after reconstitution in water.

Freeze drying further allowed delivering a pulp with a superior chewy perception after reconstitution .

Freeze dried pulp was also shown to have the best rehydration properties .

Freeze drying also allowed it to minimize pulp shrinkage during the drying procedure compared to other drying processes Notably, the inventors also found that using fresh unprocessed fruit or vegetables as starting material rather than processed fruit pulp after squeezing out juice, allows increasing the freeze drying efficiency significantly so that far more dried pulp can be produced per freeze drying vessel with the same volume.

The fruit or vegetable pulp may be cut before drying, e.g., freeze drying. Dependant on the fruit or vegetable used, cutting may or may not be preferred. For example, for oranges, grapefruit, mango or pineapple, cutting is very helpful to ensure a uniform sample size. For pomelos, cutting may be used to obtain a uniform sample size as well. However, surprisingly, the omission of a cutting step in the pomelo pulp production still results in uniform sample sizes. Generally, a cutting step contributes to a quick restoration to resemble the appearance of fresh fruit after reconstitution in water. Cutting the pulp, e.g., into cubes or other shapes allows improving the rehydration properties of the resulting pulp preparation and allows to offer more variation in size or in shape to meet varying consumer expectations.

The pulp may be cut into pieces with an edge length in the range of about 0.5-30mm. For example, the pulp may be cut into cubes with an edge length in the range of 0.5-30mm, for example 3 - 6 mm.

The inventors have found particular good properties for cubes with an edge length of about 3 or about 6 mm. The dicing size has an effect on pulp size and visual properties. Cubes with a longer edge length produce bigger pulp segments after reconstitution and the risk to produce unwanted very fine pulp segments is reduced. For some beverage applications cutting cubes with smaller edge lengths may lead to products that are preferred from a sensoric point of view.

To allow the generation of uniform shapes and small size samples the pulp may be frozen before it is being cut.

The pulp may be blanched or steam sterilized, preferable before being frozen and/or cut.

Blanching may be carried out in a liquid solution.

Blanching will help to whiten the pulp. Blanching or steam- sterilization also can be used to stop unwanted enzyme activity in the pulp, to remove unwanted strong tastes and/or to soften the pulp, or to kill unwanted microorganism in the preparation to control the microbial level.

The pulp may be blanched in a sugar solution before it is frozen and/or dried. As sugar any food grade sugar can be used. An example is sucrose.

The sugar solution may contain water and sugar. Blanching is typically carried out in boiling water, although lower temperatures may be used. For example, the solution may be heated to at least about 60°C, at least about 80°C or at least about 100 °C.

The sugar solution may contain about 0.1-99 weight-% sugar, about 10-30 weight-% sugar, for example about 20 weight-% sugar . The duration of the blanching procedure will depend on the type of pulp used but will typically be between about 30 seconds and 8 minutes, for example about 1 - 3 minutes, such as about 2 minutes.

Such a pre-treatment of the pulp will further contribute to an excellent optical appearance of the final fruit or vegetable pulp preparation.

Further, the blanching step helps to further purify the pulp from unwanted residues of peel or other constituents which may not have been completely removed in the separation step of the pulp from the rest of the fruit or vegetable. The process of the present invention has the advantage that the individual particles of the pulp are treated very carefully, preserving their natural character and appearance.

As a result, the fruit or vegetable pulp preparation in accordance with the present invention in a dehydrated state may have more than 50% particles of a size in the range between 0.5 mm to 30 mm.

Further ingredients, e.g., such as malto dextrin, sucrose, trehalose, maltose, glucose, glycerine, or combinations thereof may be added to the pulp, for example after the bleaching step.

For example, such ingredients could be added to the pulp before it is frozen.

With the addition of these ingredients, the inventors have found that the shake-down density of the final dried pulp can be varied and can for example range from 0.02 to 0.50g/ml.

The ideal shakedown density of the pulp particles will depend on a number of factors such as the overall average size of the pulp particle as well as the nature and density of the origin composition that was used to produce the pulp particles of the present invention.

"Shakedown density" or "tap density" of a powder is understood in the art as the ratio of its mass to the volume it occupies after it has been subjected to a fixed number of taps under specified conditions (e.g. JET STAV 300, 300 jolts, stroke height at 3.0 ± 0.2 mm) . It is conventionally expressed in grams per millilitre. By using freeze drying technology it can be ensured that the resulting pulp maintains its floating status after reconstitution in water.

The pulp may be obtained from edible fruit or vegetables. "Edible" means a material that is approved for human or animal consumption.

For example, the pulp may be obtained from fruit of the genus citrus fruits, for example oranges, tangerines, lemons, grapefruits, pomelos; or apples; peaches; pineapples; cherries; apricots; grapes; guava; sapodillas; tomatoes; mangos; bananas; or combinations thereof.

Orange pulp is widely used and may hence be a preferred example .

Pomelos are a further preferred example, as they allow easy separation of the pulp from the whole fruit and show particular good visual performance. Further they have a high nutritional value and are relatively inexpensive.

The composition of the present invention may be used to prepare any kind of edible composition. Edible compositions include powdered beverages. The composition will generally be liquid prior to consumption, but this does not have to be the case. The composition may also be to be consumed in the dry state or may be to be incorporated into other compositions, for example gel like compositions or creamy compositions such as yoghurts, ice creams or puddings. The compositions of the present invention may also be to be incorporated into dry preparations such as cakes, for example.

The composition of the present invention may also be used for cosmetic compositions and/or hygiene products such as shower gels, or face masks, for example.

In one embodiment of the present invention the composition is a powdered beverage or may be a part of a powdered beverage.

Such a powdered beverage comprises the composition of the present invention.

For example, the powdered beverage may contain at least 0.1 weight-% of the fruit or vegetable pulp preparation in the dry state and optionally food additives and/or food ingredients. Food additives and/or further food ingredients may be added. The pulp preparation produced in accordance with the present invention results in a protected pulp structure and minimizes breakage during processing.

Those skilled in the art will understand that they can freely combine all features of the present invention described herein, without departing from the scope of the invention as disclosed. In particular, features described for the dried fruit or vegetable pulp preparation, and/or the powdered beverage of the present invention may be applied to the process described in the present invention and vice versa. Features described for the dried fruit or vegetable pulp preparation of the present invention may also apply to the powdered beverage of the present invention and vice versa.

Further advantages and features of the present invention are apparent from the following Examples and Figures.

Figure 1 shows an example of the process of the present invention .

Figure 2 shows the resulting fruit pulp obtained by the process of figure 1 reconstituted in water Figure 3 shows the results of a visual performance test for pulps obtained by different drying techniques

Figure 4 shows the results of a floating test for pulps obtained by different drying techniques

Figure 5 shows the results of a chewy perception test for pulps obtained by different drying techniques

Figure 6 shows the results of a rehydration properties test for pulps obtained by different drying techniques

Figure 7 shows the results of a shrinkage test for pulps obtained by different drying techniques Examples:

Fruit pulp was separated from the whole pomelo fruit. The following table summarizes this separation procedure. The percentages are given in weight-%. About 40 weight-% of the pomelo are fruit pulp an can be used for the production of the dried fruit pulp preparation of the present invention. Outer Inner Pomelo Loss Fresh

Skin Membrane Nut during pomelo peeling pulp process

Guangxi 41.8 % 14% 5.5"o 1.8% 36.9% Pomelo

The inventors have prepared dried pomelo pulp in accordance with the present invention. The pulp was cut to cubes of 3*3*3 mm and to cubes of 6*6*6 mm. The process is illustrated in figure 1 for pomelo pulp. Figure 2 shows the pomelo pulp floating after reconstitution in water

The inventors have further carried out a consumer test in order to investigate whether or not dried pulp prepared from fresh unprocessed fruit or vegetables was preferred by consumers over traditionally prepared fruit pulp from the waste products of orange juice production.

The following pulps were used:

5g of each dried pulp preparation were mixed with 500ml at ambient temperature. 10 consumers were asked to evaluate the pulp samples sensorically . The results are given below:

Clearly, the dried fruit or vegetable pulp preparation of the present invention is preferred by consumers. The tasters particularly noticed that sample 2 and 3 have a more chewy perception, look better and have a better mouthfeel than sample 1.

Further, different drying techniques were compared. In particular, pulp obtained by roller drying (RD) , air drying (AD) and vacuum drying (VD) were compared to pulp obtained by freeze drying (FD) .

rating of test samples according to their

preference on following visual attributes:

visuability, resemblance to fresh fruit and attractiveness. 5 -level Likert scale was applied: 5 stands for like very much, 4 for like moderately, 3 for neither like or dislike, 2 for dislike moderately, 1 for dislike very much.

Results Results are shown in figure 3.

Mean±SEM; *P<0.05 vs.FD

Conclusion Comparing to AD pulp (2.8±0.2) and VD pulp

(3.4±0.163), FD pomelo pulp (4.7±0.153) showed the best visual performance after reconstitution with water .

Compare chewy perception of reconstituted

dehydrated pulps made by different drying processing

Materials FD pomelo pulp, AD pomelo pulp , RD pomelo pulp

Methodology 1. Add 100 ml ambient water into glass beaker with weighted dehydrated pulp (1.50 ±0.01 g) , stir for 30 seconds and retain for 5 minutes before evaluation .

2. Sensory panel (10 people) did hedonic-scale rating of test samples according to their preference on following chewing attributes: Chew-ability, resemblance to fresh fruit. 5 - level Likert scale was applied: 5 stands for like very much, 4 for like moderately, 3 for neither like or dislike, 2 for dislike

moderately, 1 for dislike very much.

Results

Results are shown in figure 5.

Mean±SEM; *P<0.05 vs.FD

Conclusion Comparing to AD pulp (2.9±0.180) and VD pulp

(3.2±0.291), FD pomelo pulp (4±0.211) delivers much better chewing perception after reconstitution with water.

O jective Compare Rehydration Properties of reconstituted dehydrated pulps made by different drying

processing .

Materials FD pomelo pulp, AD pomelo pulp, VD pomelo pulp

Methodology 1. Add 50 ml hot water (60°C) into 50 ml tube with weighted dehydrated pulp (2.00±0.01 g) , and retain for 15 minutes at room temperature.

2. The content was filtered for 3 min under vacuum and weighed. The rehydration ratio (RR)was calculated as:

RR = W_r /W_d, where: W_r - drained weight (g) of the

rehydrated sample; W_d - weight of the dry sample used for rehydration

Results Results are shown in figure 6.

Conclusion Higher rehydration ration of FD pulp (4.71) shows that FD pulp has better rehydration capacity than AD pulp (3.81) and VD pulp (3.64).

O jective Comparison of shrinkage caused by dehydration was done with the value of specific volume of

dehydrated pulp.

Materials FD pomelo pulp, AD pomelo pulp , VD pomelo pulp

Methodology Precisely weighed 2.00± O.Olg pulp into a 100 ml graduate, pipette 32 mL vegetable oil to immerse pulp, read the volume scale (V) , calculate specific volume as:

Specific volume (mL/g) = (V-32)/2

Results Results are shown in figure 7.

Conclusion Higher specific volume indicated that less pulp shrinkage during drying processing, therefore pulp shrinkage induced by FD (3.5 mL/g) is much less than that caused by AD and VD (1, 2 mL/g

respectively) .

Claims

Claims :

1. Dried fruit or vegetable pulp preparation obtained from fresh, unprocessed fruits or vegetables to be added to powdered beverages, cereals, yogurt, icecream or pet^¬ food .

2. Fruit or vegetable pulp preparation in accordance with claim 1, obtainable by a process comprising the steps of separating the pulp from the fruits or vegetables and drying the pulp.

3. Fruit or vegetable pulp preparation in accordance with claim 2, wherein the pulp is dried by freeze drying.

4. Fruit or vegetable pulp preparation in accordance with one of claims 2 or 3, wherein the pulp is cut before freeze drying.

5. Fruit or vegetable pulp preparation in accordance with claim 4, wherein the pulp is frozen before it is being cut .

6. Fruit or vegetable pulp preparation in accordance with one of the preceding claims wherein the pulp is blanched or steam-sterilized in a solution before it is frozen and/or dried.

7. Fruit or vegetable pulp preparation in accordance with claim 6, wherein the sugar solution is heated to at least 60°C and contains about 0.1-99 weight-% sugar.

8. Fruit or vegetable pulp preparation in accordance with claims 4 - 7, wherein the frozen pulp is cut to cubes with an edge length in the range of 0.5-30 mm, for example about 3 - 6 mm.

9. Fruit or vegetable pulp preparation in accordance with one of the preceding claims wherein the dried fruit or vegetable pulp in a dehydrated state has more than 50% particles of a size in the range between 0.5 mm to 30 mm.

10. Fruit or vegetable pulp preparation in accordance with one of the preceding claims wherein the pulp particles have a shakedown density in the range of 0.02 g/cm³ to 0.50 g/cm³.

11. Fruit or vegetable pulp preparation in accordance with one of the preceding claims, wherein the pulp is obtained from fruits of the genus citrus fruits, for example oranges, tangerines, lemons, grapefruits, pomelos; or apples; peaches; pineapples; cherries; apricots; grapes; guava; sapodillas; tomatoes; mangos; bananas; or combinations thereof.

12. Powdered Beverage comprising a fruit or vegetable pulp preparation in accordance with one of claims 1-11.

13. Powdered Beverage in accordance with claim 12 containing at least 0.1 weight-% of the fruit or vegetable pulp preparation in the dry state and optionally food additives and/or food ingredients.