Temperature-resistant freeze-dried chocolate capable of inhibiting appetite and preparation method of temperature-resistant freeze-dried chocolate

Abstract

The invention provides the temperature-resistant freeze-dried chocolate capable of inhibiting appetite, and the temperature-resistant freeze-dried chocolate is high in grease content, fluffy in taste and silky in mouth feel; the product is loose and porous, so that the product is good in re-dissolvability and can melt in the mouth without chewing, and good sensory experience is brought to consumers; the product has a stable structural framework, does not have obvious morphology change at a high temperature of 80 DEG C, does not deform, crack and blacken due to grease melting and crystal transformation, does not have the problem that grease leaks and adheres to a packaging bag, and has excellent thermal stability.

Description

Technical Field

[0001] The invention belongs to the field of food processing and relates to freeze-dried chocolate and a preparation method thereof. Background Art

[0002] Chocolate is a food that is deeply loved by the public, but traditional chocolate is unstable at high temperatures, which increases the cost of storage, transportation and sales, so freeze-dried chocolate came into being.

[0003] EP1072199A4 discloses a freeze-dried chocolate preparation process, which is to add fat during the liquid or sauce making process, with the goal of providing a smoother taste than other freeze-dried foods. However, when the packaged chocolate product is placed at a high temperature above 55°C, fat will precipitate and stick to and contaminate the packaging, and the product will also deform.

[0004] CN115997834A provides a method for preparing freeze-dried chocolate by freeze-drying chocolate powder as a raw material. The raw material must contain chocolate powder, and the total fat content in the chocolate powder is ≤25%.

[0005] CN116508870B discloses a preparation process of freeze-dried chocolate, which uses water-soluble ingredients as the structural skeleton of freeze-dried chocolate. The product has a hard and crisp taste and is not easy to melt in the mouth, requiring more chewing. It will crack and the surface will turn black at high temperatures, which greatly reduces the sensory experience of consumers.

[0006] Therefore, it is necessary to further study the preparation process and products of freeze-dried chocolate. Summary of the invention

[0007] In one aspect, the present invention provides a freeze-dried chocolate having a porous microstructure.

[0008] In some embodiments, the freeze-dried chocolate completely dissolves in 100-fold volume of water at 20-40° C. in 3-10 seconds.

[0009] In some embodiments, the freeze-dried chocolate has a collapse degree of less than 4% after being heated at 80° C. for 0.5 hours.

[0010] In some embodiments, the freeze-dried chocolate has a moisture content of ≤ 3%.

[0011] In some embodiments, the ingredients of the freeze-dried chocolate include: fats and water-soluble ingredients, the fat ingredients include cocoa solids and medium-chain triglycerides, the water-soluble ingredients include sugar alcohols, inulin and whey protein powder, and the mass of the fat is 70-80% of the sum of the masses of the raw materials.

[0012] In some embodiments, the cocoa solids are one or more of cocoa liquor, cocoa butter, or cocoa powder.

[0013] In some embodiments, the medium chain triglyceride is medium chain triglyceride microencapsulated powder.

[0014] In some embodiments, the mass of the whey protein is 5% to 8% of the sum of the masses of the raw materials.

[0015] In some embodiments, the mass of the inulin is 5% to 10% of the sum of the masses of the raw materials.

[0016] In some embodiments, the mass of the medium chain triglycerides is 10% to 15% of the sum of the masses of the raw materials.

[0017] In some embodiments, the freeze-dried chocolate further comprises crushed nuts, and the mass of the crushed nuts does not exceed 5% of the sum of the masses of the various raw materials.

[0018] In some embodiments, the nut pieces are almond pieces.

[0019] In some embodiments, the freeze-dried chocolate is substantially Figure 1 shown.

[0020] Another aspect of the present invention provides a method for preparing the freeze-dried chocolate according to the first aspect of the present invention, the method comprising the following steps:

[0021] (1) stirring and dispersing the raw material liquid to obtain a dispersion liquid;

[0022] (2) performing a first pre-freezing treatment on the dispersion;

[0023] (3) Tempering and temperature adjustment;

[0024] (4) performing a second pre-freezing treatment;

[0025] (5) Drying,

[0026] Wherein, the temperature of the first pre-freezing treatment in step (2) is -40 to -25°C; the temperature of the tempering temperature adjustment in step (3) is -10 to 10°C, preferably -10 to -6°C; the temperature of the second pre-freezing treatment in step (4) is -50 to -30°C, preferably -40 to -36°C; the drying in step (5) is divided into primary drying and secondary drying, the temperature of the primary drying is 15 to 35°C, preferably 26 to 34°C, the time of the primary drying is 2 to 3 hours, the temperature of the secondary drying is 46 to 50°C, and the time of the secondary drying is 18 to 20 hours,

[0027] The raw material liquid is obtained by adding water to the raw material containing the freeze-dried chocolate component, and the mass of water in the raw material liquid is 1 to 3 times, preferably 2 to 3 times, the sum of the masses of the raw materials.

[0028] In some embodiments, the stirring and dispersing step in step (1) is carried out in a colloid mill or a high-pressure homogenizer, preferably in a colloid mill.

[0029] In some embodiments, the rotation speed of the colloid mill is 2500-3000 rpm.

[0030] The freeze-dried chocolate prepared by the present invention has the following characteristics:

[0031] (1) The fat content is more than 70%, and the taste is smooth;

[0032] (2) The inulin in the ingredients provides dietary fiber, effectively lowers cholesterol, enhances satiety, and effectively suppresses appetite;

[0033] (3) The medium-chain triglycerides in the ingredients can enhance satiety, effectively suppress appetite, reduce abdominal fat accumulation, and improve the body's absorption of nutrients such as minerals and essential amino acids. The medium-chain triglyceride microcapsule powder used further effectively prevents the oxidation and rancidity of oils and fats, thereby improving product quality;

[0034] (4) The product is loose and porous, making it easy to dissolve in the mouth without chewing, thus providing consumers with a wonderful sensory experience.

[0035] (5) The structural skeleton is stable. There is no obvious morphological change at a high temperature of 80°C. It will not deform, crack or turn black due to the melting and crystallization of the oil. There is no problem of oil leakage and adhesion to the packaging bag. It has excellent thermal stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a real shot of the sample obtained in Example 1;

[0037] Figure 2 The results of the resolubility experiment of Example 1 and the commercially available product "Daily Black Chocolate" are shown below;

[0038] Figure 3 The changes in the apparent morphology of Example 1 and the commercially available product "Daily Black Chocolate" before and after the thermal stability test;

[0039] Figure 4 The microscopic morphological changes of Example 1 and the commercially available product "Daily Black Chocolate" before and after the thermal stability test;

[0040] Figure 5 The figure is a comparison of the collapse degree of Example 1 and the commercially available product "Daily Black Chocolate" after the thermal stability test. DETAILED DESCRIPTION

[0041] The following specific embodiments are further detailed descriptions of the present invention.

[0042] In the present invention, unless otherwise specified, the scientific and technical terms used in the present invention have the meanings commonly understood by those skilled in the art. In addition, the laboratory operation steps used in the present invention are all conventional steps widely used in the corresponding fields.

[0043] the term:

[0044] The terms “having”, “including” and “comprising” should be interpreted as open ended, indicating the presence of the listed elements but not excluding the existence, presence or addition of any other one or more elements that are not listed.

[0045] All ranges recited herein include those endpoints of the range between the two values ​​recited. All values ​​recited herein, whether or not stated, include the expected degree of experimental error, technical error, and instrumental error for the given technique used to measure the value.

[0046] In the present invention, unless otherwise specified, % is a percentage of weight / weight (w / w).

[0047] In the present invention, "collapse degree" is the ratio of the height difference of the sample to the original height.

[0048] In the present invention, the freeze-dried chocolate may further include other food supplementary materials to further enrich the taste of the freeze-dried chocolate, for example, oatmeal crumbs, oatmeal pulp powder, puffed oats, nut crumbs, fruit pulp, and fruit pulp may be added as other supplementary materials. Other ingredients will not destroy the loose and porous microstructure of the freeze-dried chocolate.

[0049] The following examples are intended to illustrate the present invention but are not intended to limit the scope of the present invention in any way.

[0050] Example 1

[0051] The specific formula of chocolate is shown in Table 1

[0052] Table 1 Specific formula of freeze-dried chocolate A

[0053]

[0054]

[0055] 1. Preparation of raw material solution:

[0056] Add 600g of 50-55℃ water to 500g of cocoa butter block and stir until fully dissolved, set aside; weigh the remaining raw materials according to proportion and pre-mix evenly, add 900g of water to dissolve, pass through a colloid mill at a speed of 2500rpm, then boil and cool to below 35℃, mix with cocoa butter liquid, pass through a colloid mill to disperse, and pass through a 20-mesh sieve.

[0057] 2. Spread the plate: Pour the raw material liquid into the mold, remove the bubbles on the surface, and spread the surface evenly with a spatula.

[0058] 3. Freeze-drying:

[0059] (1) First pre-freezing treatment: temperature is -40°C, time is 2.5h;

[0060] (2) Tempering treatment: temperature is -10°C, time is 1.5h;

[0061] (3) Second pre-freezing treatment, temperature is -40°C, time is 2.5h;

[0062] (4) Drying treatment: primary drying and secondary drying are carried out successively. The primary drying temperature is 26°C and the time is 3 h. The secondary drying temperature is 46°C and the time is 20 h.

[0063] 4. Remove the freeze-dried chocolate from the mold.

[0064] Example 2

[0065] The specific formula of chocolate is shown in Table 2

[0066] Table 2 Specific formula of freeze-dried chocolate B

[0067] Element Dosage(%) Cocoa Butter 42 Cocoa powder 21 Maltitol 10 Inulin 7 Whey Protein Concentrate 6.5 Medium Chain Triglyceride Microcapsule Powder 10 Almonds 3.5

[0068] 1. Preparation of raw material solution:

[0069] Add 800g of 50-55℃ water to 400g of cocoa butter and 200g of cocoa powder, stir until fully dissolved, and set aside; weigh the remaining raw materials in proportion and pre-mix them evenly, add 2000g of water to dissolve, and then pass through a colloid mill at a speed of 3000rpm, then boil and cool to below 35℃, mix with cocoa butter liquid, pass through a colloid mill to disperse, and pass through a 20-mesh sieve.

[0070] 2. Spread the plate: Pour the raw material liquid into the mold, remove the bubbles on the surface, and spread the surface evenly with a spatula.

[0071] 3. Freeze-drying:

[0072] (1) First pre-freezing treatment: temperature is -30°C, time is 3 h;

[0073] (2) Tempering treatment: temperature is -6°C, time is 1h;

[0074] (3) Second pre-freezing treatment, temperature is -36°C, time is 3h;

[0075] (4) Drying: primary drying and secondary drying were carried out successively. The primary drying temperature was 34°C for 2 h, and the secondary drying temperature was 50°C for 18 h.

[0076] 4. Remove the freeze-dried chocolate from the mold.

[0077] Example 3

[0078] The specific formula of chocolate is shown in Table 3

[0079] Table 3 Specific formula of freeze-dried chocolate C

[0080] Element Dosage(%) Cocoa Butter 30 Cocoa powder 21.4 Cocoa mass 8.6 Maltitol 15 Inulin 5 Whey Protein Concentrate 5 Medium Chain Triglyceride Microcapsule Powder 15

[0081] 1. Preparation of raw material solution:

[0082] Add 1000g of 50-55℃ water to 350g of cocoa butter, 100g of cocoa liquor and 250g of cocoa powder, stir until fully dissolved and set aside; weigh the remaining raw materials in proportion and premix evenly, add 2000g of water to dissolve, pass through a colloid mill at a speed of 2800rpm, boil and cool to below 35℃, mix with cocoa butter liquor, pass through a colloid mill to disperse, and pass through a 20-mesh sieve.

[0083] 2. Spread the plate: Pour the raw material liquid into the mold, remove the bubbles on the surface, and spread the surface evenly with a spatula.

[0084] 3. Freeze-drying:

[0085] (1) First pre-freezing treatment: temperature is -25°C, time is 3h;

[0086] (2) Tempering treatment: temperature is -8°C, time is 1h;

[0087] (3) Second pre-freezing treatment, temperature is -38°C, time is 3h;

[0088] (4) Drying treatment: primary drying and secondary drying are carried out successively. The primary drying temperature is 30°C and the time is 2 h. The secondary drying temperature is 47°C and the time is 18 h.

[0089] 4. Remove the freeze-dried chocolate from the mold.

[0090] The moisture content of the freeze-dried chocolate prepared in Examples 1 to 3 was tested, and the moisture content was no more than 3%. The freeze-dried chocolate sample obtained in Example 1 was used for the following comparative experiment with the commercially available "Daily Dark Chocolate" freeze-dried chocolate.

[0091] Sensory attribute evaluation

[0092] According to the sensory attribute evaluation criteria described in Table 4, the evaluation results are shown in Table 5.

[0093] Table 4 Sensory attribute evaluation criteria

[0094]

[0095] Table 5 Sensory attribute evaluation results

[0096]

[0097] The freeze-dried chocolate prepared by the present invention is significantly different from the commercially available product "Daily Dark Chocolate" in terms of melting time in the mouth. The commercially available product has a hard texture and needs to be chewed to slowly melt; the product of the present invention has a fluffy texture and melts in the mouth, which can bring consumers a brand new taste bud experience.

[0098] Resolubility test

[0099] Place the sample in a beaker and inject 200 ml of 37°C warm water to completely immerse the sample. Record the sample dissolution time. The results are as follows: Figure 2 As shown, the sample obtained by the present invention is completely dissolved within 5 seconds, while the commercially available product "Daily Black Chocolate" is still not completely dissolved after 1.5 hours.

[0100] Thermal stability test

[0101] The samples were heated in a drying oven at 30°C, 40°C, 50°C, 60°C, 70°C, and 80°C for 0.5 h each. Finally, the temperature was cooled to room temperature, and the morphology changes were observed. The height of the samples before and after heating was measured with a vernier caliper, and their microstructure was observed with a 100x optical microscope.

[0102] The present invention controls the ratio of the amount of water to the sum of the masses of the raw materials within an appropriate range, so that the obtained freeze-dried product has a more suitable density and porosity in the microstructure. Figure 3 , Figure 4 It can be seen that the commercially available product "Daily Black Chocolate" has a dense and tight structure in its original state at room temperature, while the sample obtained in the present invention has a loose and porous honeycomb structure with a larger specific surface area, which is also the reason for the above-mentioned differences in taste and re-dissolution speed between the two.

[0103] The commercially available product "Daily Black Chocolate" will gradually turn black and crack after being heated at a high temperature of not less than 30°C for half an hour. After being heated at 80°C for half an hour, the height will collapse from 0.528 inches to 0.451 inches, with a collapse rate of 14.6% (such as Figure 5), collapse and cracks can be clearly observed in the microstructure; while the overall structure, color and micromorphology of the sample obtained by the present invention do not change much. After heating at 80°C for half an hour, the height collapses from 0.687 inches to 0.663 inches, and the collapse degree is only 3.5%, and the product has better thermal stability.

[0104] Cocoa butter has 6 crystal forms, from I to VI. For chocolate and chocolate products, the metastable V-type crystal, which is relatively stable and has a glossy appearance, is a more ideal crystal structure. As the temperature rises, the V-type crystal will further transform into the VI crystal, resulting in coarse crystal particles and affecting the taste. The blackening of "Daily Dark Chocolate" at high temperatures may be due to the melting of cocoa butter and the change of crystal form. The present invention uses a special preparation process to allow the fat in the content to melt again and then re-crystallize plastically, resulting in a better and more stable crystal structure.

[0105] The above embodiments are intended to illustrate the essential content of the present invention, but are not intended to limit the protection scope of the present invention. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and protection scope of the technical solution of the present invention.

Claims

1. A freeze-dried chocolate, characterized in that: The freeze-dried chocolate has a porous microstructure.

2. The freeze-dried chocolate according to claim 1, characterized in that: The freeze-dried chocolate is completely dissolved in 3 to 10 seconds in water at 20 to 40° C. and 100 times the volume.

3. The freeze-dried chocolate according to claim 1, characterized in that: After the freeze-dried chocolate was heated at 80° C. for 0.5 hour, the collapse degree was less than 4%.

4. The freeze-dried chocolate according to claim 1, characterized in that: The moisture content of the freeze-dried chocolate is ≤3%.

5. The freeze-dried chocolate according to any one of claims 1 to 4, characterized in that The freeze-dried chocolate comprises: oil and water-soluble ingredients, wherein the oil comprises cocoa solids and medium-chain triglycerides, and the water-soluble ingredients comprise sugar alcohol, inulin and whey protein powder, and the mass of the oil is 70-80% of the sum of the masses of the raw materials.

6. The freeze-dried chocolate according to claim 5, characterized in that: The cocoa solids are one or more of cocoa liquor, cocoa butter or cocoa powder; or The medium chain triglyceride is medium chain triglyceride microcapsule powder; or The mass of the whey protein is 5% to 8% of the sum of the masses of the raw materials; or The mass of the inulin is 5% to 10% of the sum of the masses of the raw materials; or The mass of the medium chain triglycerides is 10% to 15% of the sum of the masses of the raw materials; or The freeze-dried chocolate also includes crushed nuts, and the mass of the crushed nuts does not exceed 5% of the total mass of all raw materials.

7. A method for preparing the freeze-dried chocolate according to claim 5, characterized in that: The preparation method comprises the following steps: (1) stirring and dispersing the raw material liquid to obtain a dispersion liquid; (2) performing a first pre-freezing treatment on the dispersion; (3) Tempering and temperature adjustment; (4) performing a second pre-freezing treatment; (5) Drying, Wherein, the temperature of the first pre-freezing treatment in step (2) is -40 to -25°C; The tempering temperature in step (3) is -10 to 10°C, preferably -10 to -6°C; The temperature of the second pre-freezing treatment in step (4) is -50 to -30°C, preferably -40 to -36°C; The drying in step (5) is divided into primary drying and secondary drying. The primary drying temperature is 15 to 35° C., preferably 26 to 34° C., and the primary drying time is 2 to 3 hours. The secondary drying temperature is 46 to 50° C., and the secondary drying time is 18 to 20 hours.

8. The preparation method according to claim 7, characterized in that: The raw material liquid is obtained by adding water to the raw material containing the freeze-dried chocolate component, and the mass of water in the raw material liquid is 1 to 3 times, preferably 2 to 3 times, the sum of the masses of the raw materials.

9. The preparation method according to claim 7, characterized in that: The stirring and dispersing step is carried out in a colloid mill or a high-pressure homogenizer, preferably in a colloid mill.

10. The preparation method according to claim 9, characterized in that: The rotation speed of the colloid mill is 2500-3000 rpm.

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