Fruit-flavored milk powder and preparation method thereof

Abstract

The invention discloses a method for preparing a fruit-flavored milk powder, comprising the following steps: washing and cutting the fruit, blanching to inactivate enzymes, beating and juicing the fruit pieces after the blanching to inactivate enzymes, filtering, adjusting the pH of the filtrate, adding gelatin to remove tannins, standing, filtering again, and obtaining fruit juice; using raw milk as a raw material, pasteurizing, adding fruit juice and skim milk powder, and then post-processing to obtain fruit juice milk powder. The fruit-flavored milk powder prepared by the invention has good dispersibility, is easy to brew, has a strong milky and fruity aroma, has a smooth taste without a granular feel, and is provided with a sugar bag to meet consumers' needs for different sweetness.

Description

Technical Field

[0001] The invention belongs to the field of food processing, and particularly relates to fruit-flavored milk powder and a preparation method thereof. Background Art

[0002] Fruit-flavored milk powder satisfies consumers' demands for both milk nutrition and fruit flavor, and is a major trend in the milk powder industry. At present, most fruit-flavored milk powders on the market are made by adding fruit powder to milk powder, which results in poor taste and brewing performance of fruit-flavored milk powders. Some other fruit-flavored milk powder products only add pigments and flavors to milk powder to make fruit flavors, without adding fruit at all, which poses certain risks to consumer health. Most fruits are acidic after being squeezed into juice, and the tannins and enzymes in the juice have a certain impact on the production of fruit-flavored milk powder. For example, adding fruit juice to milk will cause protein precipitation and produce bitterness. Therefore, solving the above problems is the technical key to the production of fruit-flavored milk powder, which is of strategic significance to expanding the fruit-flavored milk powder market. Summary of the invention

[0003] The problem to be solved by the invention is to provide a fruit-flavored milk powder with good appearance and taste and a preparation method thereof.

[0004] In order to solve the above technical problems, the present invention provides a method for preparing fruit-flavored milk powder, comprising the following steps:

[0005] (1) Juice preparation

[0006] 1.1) Wash the fruits, cut them into pieces, and blanch them to inactivate enzymes;

[0007] 1.2) Pulp and juice the fruit pieces after the enzyme activity is inactivated by blanching, filter, adjust the pH of the filtrate, add gelatin to remove tannin, let stand, filter again, and obtain juice;

[0008] (2) Preparation of fruit juice milk powder

[0009] Using raw milk as raw material, after pasteurization, adding fruit juice and skim milk powder, and then post-processing, juice milk powder is obtained;

[0010] The weight ratio of raw milk: fruit juice: skimmed milk powder = 100:5~20:2~5.

[0011] As an improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0012] The post-treatment of step (2) is to successively perform homogenization, sterilization, concentration, spray drying, fluidized bed drying (secondary drying), cooling, and sieving to obtain fruit juice milk powder.

[0013] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0014] White sugar is screened, sterilized, measured and bagged (measured and bagged after gold inspection);

[0015] Measuring and bagging of juice and milk powder (measuring and bagging after metal inspection);

[0016] Put the bagged fruit juice milk powder and the bagged white sugar into the same packaging container, pack them into boxes and store them in a warehouse; the mass ratio of the bagged fruit juice milk powder to the bagged white sugar is 30-40:5-15.

[0017] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0018] In the step 1.1), the blanching temperature is 90±5° C. and the blanching time is 3 to 5 minutes.

[0019] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0020] In the step 1.2), the pH of the filtrate is adjusted to 5.5-6.5 using sodium citrate.

[0021] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0022] In the step 1.2), a gelatin solution with a mass concentration of 9 to 11% is added for tanning, the volume ratio of the filtrate to the gelatin solution is 100:10 to 15, and the mixture is stirred (the gelatin solution is stirred slowly and then quickly) until no precipitation is generated, and the stirring speed is 100 to 140 r / min; then the mixture is refrigerated at 4 to 8° C. for 16 to 20 hours, and filtered again to obtain the juice.

[0023] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0024] In the step (2), the homogenization process adopts two-stage homogenization, first low pressure and then high pressure, the low pressure homogenization pressure is 5-10MPa, the high pressure homogenization pressure is 20-100MPa, and the temperature is 45-55°C.

[0025] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0026] Add water to the fruit pieces after blanching to inactivate the enzymes and then blend and squeeze out the juice.

[0027] That is, an appropriate amount of water can be added during the pulping and juicing process according to actual conditions.

[0028] As a further improvement of the preparation method of the fruit-flavored milk powder of the present invention:

[0029] The juice obtained in step (1) is clarified and then used in step (2).

[0030] That is, the juice obtained in step (1) can be clarified by adding chitosan according to actual conditions.

[0031] The present invention also provides fruit-flavored milk powder (which is an instant tea milk solid beverage) prepared by the method.

[0032] The invention uses fruit and raw milk as main raw materials, adjusts the pH value of juice, kills the activity of enzyme substances, removes tannins in the juice, and prepares instant fruit-flavored milk powder with good appearance and taste.

[0033] In the present invention, the fruit is not limited to any kind, and can be one or more fruits such as apples, strawberries, blueberries, bananas, grapes, etc. According to the different fruit types, the fruit is washed, peeled or cored, and cut into pieces.

[0034] Compared with the prior art, the present invention has the following technical advantages:

[0035] 1. The fruit-flavored milk powder of the present invention is actually added with fruit juice, and has rich frankincense and fresh fruity aroma.

[0036] 2. Blanching kills the activity of enzymes in fruits to prevent milk protein from producing bitterness due to degradation by fruit enzymes; sodium citrate adjusts the pH of juice to prevent milk protein from precipitating due to fruit acidic substances; gelatin removes tannins in juice to prevent milk protein from combining with tannins and precipitating;

[0037] 3. The fruit-flavored milk powder prepared by the present invention has good dispersibility, is easy to brew, has a strong milky and fruity aroma, a smooth taste without a sense of grain, and is provided with a sugar bag to meet consumers' needs for different sweetness. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings.

[0039] Figure 1 The present invention provides a process diagram for preparing the fruit-flavored milk powder. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0041] The acceptance of raw milk should comply with GB19301 "National Food Safety Standard for Raw Milk"; the acceptance of various types of fruits should comply with the corresponding safety standards and / or relevant regulations of the fruit.

[0042] The pasteurization of raw milk is conventional, that is, sterilization at 85-85°C for 15-20s.

[0043] Example 1: Preparation of strawberry milk powder, the following steps are carried out in sequence:

[0044] (1) Juice preparation

[0045] 1.1) Wash the qualified strawberries, remove the stems, cut into pieces, and blanch at 90℃ for 3-5 minutes to inactivate enzyme activity;

[0046] 1.2) After blanching, remove from the water, beat and squeeze out the juice (beating at 800-850 r / min for 5-10 min), filter, adjust the pH value of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:10, slowly increase the stirring speed until no precipitation occurs, the stirring speed is 100-140 r / min, stand and refrigerate overnight (stand and refrigerate at 4-8°C for 16-20 h), filter twice, and obtain strawberry juice.

[0047] 10% gelatin, obtained by evenly mixing 10g gelatin with 90g water.

[0048] (2) Preparation of fruit juice milk powder

[0049] The qualified raw milk is pasteurized and then added with strawberry juice and skim milk powder, wherein the amount of strawberry juice added is 15% of the raw milk and the amount of skim milk powder added is 2% of the raw milk; and then subjected to conventional post-processing, juice milk powder (strawberry milk powder) is obtained.

[0050] The above % is % by weight.

[0051] Conventional post-processing is to carry out the following steps in sequence:

[0052] First, it is homogenized (using two-stage homogenization, low pressure first and then high pressure, low pressure homogenization pressure 5-10Mpa, time is 20-30min, high pressure homogenization pressure 20-100Mpa, time is 10-20min, temperature 45-55℃), sterilized (100-110℃ sterilization for 10-15s), concentrated (the density of the discharged material after concentration is 1000-1100kg / m 3 ), spray drying, fluidized bed drying, cooling (cooling to below 40° C.), sieving (through a 40-60 mesh sieve), and gold inspection, and the obtained strawberry milk powder is measured and bagged at 35 g per bag.

[0053] After sieving (through a 20-30 mesh sieve), sterilizing (ultraviolet sterilization for more than 40 seconds), and gold inspection, the white sugar is measured and bagged at 10g per bag.

[0054] Put the bagged strawberry milk powder and bagged white sugar into 380mL cups, pack them into boxes and store them in warehouses.

[0055] Example 2: Preparation of apple banana milk powder, the following steps are carried out in sequence:

[0056] (1) Juice preparation

[0057] 1.1) Wash and cut the qualified apples into pieces, and blanch them at 90℃ for 3-5 minutes to inactivate enzyme activity;

[0058] 1.2) After blanching, remove from the water, beat and squeeze out the juice (beating at 800-850 r / min for 5-10 min), filter, adjust the pH value of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:15, slowly increase the stirring speed until no precipitation occurs, the stirring speed is 100-140 r / min, let it stand and refrigerate overnight (let it stand and refrigerate at 4-8°C for 16-20 h), filter twice, add chitosan to the filtrate for clarification (add 2 g of chitosan to every 100 ml of filtrate and let it stand for 24 h) to obtain apple juice.

[0059] 1.3) Wash, peel, cut and scald the bananas at 90℃ for 3 minutes to inactivate enzymes;

[0060] 1.4) After blanching, remove from the water, beat with pulp, add water and squeeze out the juice (beat at 800-850 r / min for 5-10 min, the weight ratio of banana pieces to water is 1:2), filter, adjust the pH value of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:10, slowly increase the stirring speed until no precipitation is produced, the stirring speed is 100-140 r / min, stand and refrigerate overnight (stand and refrigerate at 4-8°C for 16-20 h), filter twice, and obtain banana juice.

[0061] (2) Preparation of fruit juice milk powder

[0062] The qualified raw milk is pasteurized and then added with apple juice, banana juice and skim milk powder, wherein the amount of apple juice added is 8% of the raw milk, the amount of banana juice added is 5% of the milk, and the amount of skim milk powder added is 3% of the raw milk; and then after conventional post-processing, juice milk powder (apple banana milk powder) is obtained.

[0063] After screening, sterilization and gold inspection, the white sugar is packed in bags at 5g per bag.

[0064] Put the bagged apple banana milk powder and bagged white sugar into 380mL cups, pack them into boxes and store them in warehouses.

[0065] Comparative Example 1: The step 1.1) of Example 1, in which "the step of blanching at 90° C. for 3 to 5 min to inactivate enzyme activity" is omitted, that is, the diced strawberries are directly pulped and juiced, and the rest is the same as Example 1.

[0066] Comparative Example 2, the step 1.2) of Example 1, in which "the pH value of the filtrate is adjusted to 6.0-6.5 with sodium citrate" is omitted, that is, 10% gelatin is directly added after pulping, squeezing and filtering the juice, and the rest is the same as Example 1.

[0067] Comparative Example 3-1, the step 1.2) of Example 1) gelatin was omitted, that is, the pH of the filtrate was adjusted to 6.0-6.5 with sodium citrate, and the filtrate was refrigerated overnight and filtered twice to obtain strawberry juice.

[0068] Comparative Example 3-2: The volume ratio of the filtrate to the gelatin solution in step 1.2) of Example 1 was changed to 100:5; the rest was the same as Example 1.

[0069] Experiment 1: A sensory evaluation was performed on the fruit-flavored milk powder samples of Example 1 and Comparative Examples 1 to 3-2. The sensory evaluation standards are shown in Table 1.

[0070] Table 1. Sensory evaluation standards for fruit-flavored milk powder

[0071]

[0072]

[0073] The results are shown in Table 2 below.

[0074] Table 2. Sensory evaluation scores of fruit-flavored milk powder

[0075] sample Taste state odor Color Comprehensive score Example 1 27±3 28±5 19±3 18±1 92±5 Comparative Example 1 24±4 21±3 18±5 18±2 81±6 Comparative Example 2 23±5 19±4 18±3 17±2 77±4 Comparative Example 3-1 21±4 23±3 19±5 18±3 81±7 Comparative Example 3-2 24±4 23±6 18±4 18±2 83±5

[0076] The fruit-flavored milk powder of Example 1 of the present invention has the highest sensory evaluation score, especially in taste and state.

[0077] Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. The preparation of strawberry milk powder is characterized in that Follow these steps in order: (1) Juice preparation 1.1) Wash the strawberries, remove the stems, cut into pieces, and blanch at 90℃ for 3-5 minutes to inactivate the enzyme; 1.2) After blanching, remove from the water, beat at 800-850 r / min for 5-10 min to extract the juice, filter, adjust the pH of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:10, slowly increase the stirring speed until no precipitation occurs, the stirring speed is 100-140 r / min, stand and refrigerate at 4-8℃ for 16-20 h, filter twice, and obtain strawberry juice; 10% gelatin, made by mixing 10g gelatin with 90g water; (2) Preparation of fruit juice and milk powder The qualified raw milk is pasteurized and then added with strawberry juice and skim milk powder, with the amount of strawberry juice added being 15% of the raw milk and the amount of skim milk powder added being 2% of the raw milk; and then subjected to conventional post-processing to obtain strawberry milk powder; The above % are weight%; Conventional post-processing is to carry out the following steps in sequence: Firstly, it is homogenized, sterilized at 100-110℃ for 10-15 seconds, and concentrated until the density of the discharged material is 1000-1100 kg / m 3 , spray drying, fluidized bed drying, cooling to below 40°C, passing through a 40-60 mesh sieve, gold inspection, and packing the obtained strawberry milk powder into bags at a rate of 35 g per bag; The homogenization is carried out in two stages, first at low pressure and then at high pressure, the low pressure homogenization pressure is 5-10 Mpa, the time is 20-30 min, the high pressure homogenization pressure is 20-100 Mpa, the time is 10-20 min, and the temperature is 45-55°C; After the white sugar is sieved with 20-30 mesh, sterilized with ultraviolet light for more than 40 seconds, and inspected by gold, it is measured and bagged at 10 g per bag; Put the bagged strawberry milk powder and bagged white sugar into 380 mL cups, pack them into boxes and store them in warehouse.

2. The preparation of apple banana milk powder is characterized in that Follow these steps in order: (1) Juice preparation 1.1) Wash the apples, cut them into pieces, and blanch them at 90℃ for 3-5 minutes to inactivate the enzyme; 1.2) After blanching, remove from the water, beat at 800-850 r / min for 5-10 min to extract the juice, filter, adjust the pH value of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:15, slowly increase the stirring speed until no precipitation occurs, the stirring speed is 100-140 r / min, stand and refrigerate at 4-8℃ for 16-20 h, filter twice, add 2g of chitosan to every 100ml of the filtrate and stand for 24 h to clarify, and obtain apple juice; 1.3) Wash, peel, cut and scald the bananas that have passed the inspection at 90℃ for 3 minutes to inactivate the enzyme; 1.4) After blanching, remove from the water, beat with pulp, add water to squeeze out the juice, filter, adjust the pH value of the filtrate to 6.0-6.5 with sodium citrate, slowly add 10% gelatin, the volume ratio of the filtrate to the gelatin solution is 100:10, slowly increase the stirring speed until no precipitation occurs, the stirring speed is 100-140 r / min, stand and refrigerate at 4-8℃ for 16-20 hours, filter twice, and obtain banana juice; The pulping and watering for juicing is as follows: 800-850 r / min for 5-10 min, with a weight ratio of banana pieces to water of 1:2; (2) Preparation of fruit juice and milk powder After the qualified raw milk is pasteurized, apple juice, banana juice and skim milk powder are added, with the amount of apple juice added being 8% of the raw milk, the amount of banana juice added being 5% of the milk, and the amount of skim milk powder added being 3% of the raw milk; and then undergoing conventional post-processing, apple banana milk powder is obtained; The above % are weight%; After sieving, sterilizing and gold inspection, the white sugar is measured and packed into bags at 5 g per bag; Put the bagged apple banana milk powder and bagged white sugar into 380 mL cups, pack them into boxes and store them in warehouse.

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