Special long-acting freeze-thaw stable egg liquid for frozen egg tarts with toffee flavor

Abstract

The invention discloses toffee-flavor long-acting freeze-thaw stable type special egg liquid for frozen egg tarts, and belongs to egg products. The egg tart liquid is prepared from the following raw materials in parts by weight: 90 to 140 parts of milk, 25 to 35 parts of egg yolk liquid, 80 to 120 parts of vegetable oil, 60 to 70 parts of whole egg liquid, 40 to 45 parts of single cream, 40 to 45 parts of arabinose, 0.1 to 0.3 part of table salt, 0.3 to 1.6 parts of an emulsifying agent, 0.3 to 0.6 part of a thickening agent and 60 to 110 parts of water. The baking flavor of the egg tarts is enhanced by 50-70% by carrying out the Maillard reaction on part of the feed liquid in advance and screening the specific emulsifier and the dosage proportion thereof, the egg tarts have obvious toffee aroma, and the shelf life is prolonged by 50% compared with that of products in the market.

Description

Technical Field

[0001] The invention relates to a toffee-flavored long-acting freeze-thaw-stable egg liquid special for frozen egg tarts, belonging to the field of egg products, in particular to a flavored and frozen egg tart liquid. Background Art

[0002] Egg tart liquid is an egg filling used in Western-style pie egg tarts, and its main ingredients are milk, egg liquid, sugar, etc. As consumers' acceptance of egg tarts increases, the taste requirements for egg tart liquid are also increasing. For example, CN202211549236.1 discloses a cocoa egg tart liquid and a preparation method thereof; CN201711103655.1 discloses a frozen egg tart liquid, a salted egg yolk egg tart, and a production method thereof; CN201510185394.7 discloses a chocolate egg tart and a production method thereof; CN202110840272.2 discloses a method for making a nutritious egg tart; these methods generally adopt the method of adding certain raw materials such as milk cocoa powder, salted egg yolk, etc. to give the egg tart liquid different flavors; CN202110840272.2 adopts a bacterial fermentation method to give the egg tart liquid a fermented flavor. The above existing methods all have the following problems: ① the egg tart liquid has insufficient baking aroma, ② the egg tart liquid has no toffee aroma, and ③ the freeze-thaw stability and shelf life of the egg tart liquid need to be further improved. Summary of the invention

[0003] In order to solve at least one problem that the egg tart liquid in the prior art has insufficient baking aroma, the egg tart liquid has no toffee aroma, and the freeze-thaw stability and shelf life of the egg tart liquid need to be further improved, the present invention provides a toffee-flavored long-acting freeze-thaw stable egg tart liquid by pre-Maillard reaction of part of the liquid, and screening a specific emulsifier and its usage ratio. The baking flavor of the egg tart liquid of the present invention is enhanced by 50-70%, and it has obvious toffee aroma, and the shelf life is increased by 50% compared with the market products.

[0004] The invention provides a toffee-flavored long-acting freeze-thaw stable egg liquid special for frozen egg tarts. The egg liquid special for frozen egg tarts is prepared from the following raw materials in weight proportion: 60-70 parts of whole egg liquid, 25-35 parts of egg yolk liquid, 80-120 parts of vegetable oil, 40-45 parts of cream, 40-45 parts of arabinose, 0.1-0.3 parts of salt, 0.3-1.6 parts of emulsifier, 0.3-0.6 parts of thickener, 90-140 parts of milk and 60-110 parts of water.

[0005] In one embodiment of the present invention, the emulsifier is a combination system of Span 60, Tween 60, and mono- and di-glycerol stearates.

[0006] In one embodiment of the present invention, the weight ratio of each component in the emulsifier is: 0.1-0.3 parts of Span 60, 0.1-1 parts of Tween 60, and 0.1-0.3 parts of mono- and di-glycerol stearate.

[0007] In one embodiment of the present invention, the ratio of Span 60, Tween 60, and mono- and di-glycerol stearates in the emulsifier is 1:(2-3):1.

[0008] In one embodiment of the present invention, the egg tart liquid is prepared with milk, egg yolk liquid, arabinose, whole egg liquid, cream, vegetable oil and the like as main raw materials, and salt, emulsifier, thickener and water are added, and the weight fractions of the components are respectively: 90-140 parts of milk, 25-35 parts of egg yolk liquid, 80-120 parts of vegetable oil, 60-70 parts of whole egg liquid, 40-45 parts of cream, 40-45 parts of arabinose, 0.1-0.3 parts of salt, 0.1-0.3 parts of Span 60, 0.1-1 parts of Tween 60, 0.1-0.3 parts of mono- and di-stearate of glycerol, 0.3-0.6 parts of thickener and 60-110 parts of water.

[0009] In one embodiment of the present invention, the thickener is selected from any one or more of the following combinations: hydroxypropyl methylcellulose, sodium carboxymethyl cellulose, xanthan gum, carrageenan, locust bean gum, guar gum, agar, pectin, sodium alginate, gelatin, gellan gum, and gum arabic.

[0010] In one embodiment of the present invention, the thickener may be a combination of hydroxypropyl methylcellulose, sodium carboxymethyl cellulose and xanthan gum.

[0011] In one embodiment of the present invention, the weight ratio of each component in the thickener is: 0.1 part of hydroxypropyl methylcellulose, 0.2 part of sodium carboxymethyl cellulose, and 0.05 part of xanthan gum.

[0012] In one embodiment of the present invention, the vegetable oil is selected from any one or more combinations of the following: soybean oil, palm oil, palm kernel oil, coconut oil, rapeseed oil, sunflower oil, corn oil, peanut oil, milk fat, olive oil, and tea seed oil.

[0013] In one embodiment of the present invention, the mass ratio of milk, egg yolk liquid and L-arabinose is 3-4:1:1-1.3.

[0014] The present invention also provides a method for preparing the toffee-flavored long-acting freeze-thaw stable frozen egg tart egg liquid, comprising:

[0015] (1) mixing milk, egg yolk liquid and L-arabinose according to the above components to carry out Maillard reaction to obtain a toffee liquid;

[0016] (2) Mixing the vegetable oil, cream, salt, emulsifier, thickener and water according to the above components, dissolving and dispersing them evenly, and heating them to 65-68° C. to prepare an oil-water mixture;

[0017] (3) According to the above components, the above toffee liquid, oil-water mixture and whole egg liquid are mixed, and pasteurized at 65-68° C. for 20-30 min.

[0018] In one embodiment of the present invention, the method further comprises: subjecting the sterilized mixed liquid to secondary homogenization, with the primary pressure being 20 to 25 MPa and the secondary pressure being 10 to 15 MPa, pre-cooling the mixed liquid obtained after homogenization to 5 to 10° C., and then quick-freezing and freezing at -38 to -18° C. to obtain a toffee-flavored long-lasting freeze-thaw stable egg tart liquid.

[0019] In one embodiment of the present invention, the preparation method comprises the following steps: the egg tart liquid is subjected to Maillard reaction, mixing and homogenizing, cooling, quick freezing and other processes.

[0020] In one embodiment of the present invention, in step (1), sterilized milk can be used as milk, and pasteurized egg yolk liquid can be used as egg yolk liquid. L-arabinose is added, and after fully dissolved, the temperature is raised to 60° C. and kept in a water bath for 180 minutes; various amino acids in the milk and glutamic acid in the eggs react with L-arabinose under low temperature to produce a unique toffee flavor.

[0021] In one embodiment of the present invention, in step (2), 80-120 parts of vegetable oil, 40-45 parts of cream, 0.1-0.3 parts of salt, 0.1-0.3 parts of Span 60, 0.1-1 parts of Tween 60, 0.1-0.3 parts of mono- and di-stearate of glycerol, 0.3-0.6 parts of thickener, 60-80 parts of water, etc. are dissolved and dispersed uniformly using a vacuum emulsifying device, and the temperature is raised to 65-68° C. to prepare an oil-water mixture.

[0022] In one embodiment of the present invention, in step (3), the toffee liquid, the oil-water mixture, and 60 to 70 parts of whole egg liquid are evenly mixed and pasteurized at 65-68° C. for 20 to 30 minutes.

[0023] The invention also provides application of the toffee-flavored long-acting freeze-thaw stable frozen egg tart-specific egg liquid in food processing.

[0024] Beneficial effects:

[0025] On the one hand, the technical problem solved by the present invention is that by subjecting part of the materials to Maillard reaction in advance, the egg tart liquid can have a richer and fuller flavor after normal baking, thereby satisfying the taste requirements of consumers. The baked flavor of the egg tart liquid of the present invention is enhanced by 50-70%.

[0026] On the other hand, the technical problem further solved by the present invention is that the egg tart liquid of the present invention does not add flavors and spices, and can prepare a characteristic toffee-flavored egg tart, and the obtained egg tart has an obvious toffee aroma.

[0027] On the other hand, the technical problem solved by the present invention is that by screening a variety of emulsifiers and adjusting the ratio of emulsifiers, the freeze-thaw stability of the egg tart liquid is enhanced, and the shelf life is up to 18 months, which is 50% longer than the products on the market and has a longer shelf life and stability than the frozen egg tart liquid in CN201711103655.1.

[0028] Optimal effect: The egg tart liquid of the invention is subjected to the processes of Maillard reaction, mixing and homogenization, cooling, quick freezing, etc., and no flavor or fragrance is added to prepare a characteristic toffee-flavored egg tart. The egg tart liquid has excellent emulsion freeze-thaw stability after being frozen and stored, and has stable flavor and color within a shelf life of 18 months. The invention is convenient to use and has stable quality, and can bake egg tarts with full flavor and beautiful appearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The digital photos of the egg tart products obtained by thawing the frozen egg liquid specially used for egg tarts obtained in each embodiment and comparative example are shown.

[0030] Figure 2 The digital photos of the egg tart products are obtained by repeatedly freezing and thawing the egg liquid specially used for frozen egg tarts obtained in each embodiment and comparative example. DETAILED DESCRIPTION

[0031] The raw materials involved in the invention, such as pure milk, L-arabinose, soybean oil, cream, salt, Span 60, Tween 60, mono- and di-glycerol stearate, hydroxypropyl methylcellulose, sodium carboxymethylcellulose, xanthan gum, etc., can all be obtained commercially.

[0032] Example 1

[0033] The present embodiment provides a method for preparing a toffee-flavored long-acting freeze-thaw stable egg tart liquid, which specifically comprises the following steps:

[0034] Step 1: Mix 120 kg of pure milk, 30 kg of egg yolk liquid and 40 kg of L-arabinose, heat in a water bath to 60°C, and slowly stir for 180 minutes to obtain a toffee flavor liquid;

[0035] Step 2: 100kg soybean oil, 40kg cream, 0.3kg salt, 0.1kg Span 60, 0.3kg Tween 60, 0.1kg mono- and di-glycerol stearate, 0.1kg hydroxypropyl methylcellulose, 0.2kg sodium carboxymethyl cellulose, 0.05kg xanthan gum, and 80kg water are dissolved and dispersed uniformly using a vacuum emulsifying device, and the temperature is raised to 65-68° C. to prepare an oil-water mixture;

[0036] Step 3: Mix the toffee flavor liquid, the oil-water mixture and 60 kg of whole egg liquid;

[0037] Step 4: Heat the liquid to 66°C and sterilize for 30 minutes;

[0038] Step 5: The feed liquid is homogenized in two stages, with the first stage pressure at 20 MPa and the second stage pressure at 10 MPa;

[0039] Step 6: The homogenized liquid is quickly cooled to below 10°C, and quickly frozen at -38°C, and stored at -18°C to obtain frozen egg tart liquid.

[0040] Example 2

[0041] The present embodiment provides a method for preparing a toffee-flavored long-acting freeze-thaw stable egg tart liquid, which specifically comprises the following steps:

[0042] Step 1: Mix 90 kg of pure milk, 30 kg of egg yolk liquid and 40 kg of L-arabinose, heat in a water bath to 60°C, and slowly stir for 180 minutes to obtain a toffee flavor liquid;

[0043] Step 2: 100kg soybean oil, 40kg cream, 0.3kg salt, 0.1kg Span 60, 0.2kg Tween 60, 0.1kg mono- and di-glycerol stearate, 0.1kg hydroxypropyl methylcellulose, 0.2kg sodium carboxymethyl cellulose, 0.05kg xanthan gum, and 110kg water are dissolved and dispersed uniformly using a vacuum emulsifying device, and the temperature is raised to 65-68° C. to prepare an oil-water mixture;

[0044] Step 3: Mix the toffee flavor liquid, the oil-water mixture and 60 kg of whole egg liquid;

[0045] Step 4: Heat the liquid to 66°C and sterilize for 30 minutes;

[0046] Step 5: The feed liquid is homogenized in two stages, with the first stage pressure at 20 MPa and the second stage pressure at 10 MPa;

[0047] Step 6: The homogenized liquid is quickly cooled to below 10°C, and quickly frozen at -38°C, and stored at -18°C to obtain frozen egg tart liquid.

[0048] Comparative Example 1

[0049] Formula: 120Kg milk, 30Kg egg yolk liquid, 40kg L-arabinose, 100kg soybean oil, 40Kg cream, 0.3kg salt, 60Kg whole egg liquid, 0.1kg hydroxypropyl methylcellulose, 0.2kg sodium carboxymethyl cellulose, 0.05kg xanthan gum, 90kg water.

[0050] Step 1: Use vacuum emulsification equipment to dissolve and disperse all materials evenly, and heat to 65-68℃;

[0051] Step 2: 66℃, sterilize for 30min;

[0052] Step 3: The feed liquid is subjected to secondary homogenization, with the primary pressure being 20MPa and the secondary pressure being 10MPa;

[0053] Step 4: The homogenized liquid is quickly cooled to below 10°C, and quickly frozen at -38°C, and stored at -18°C to obtain frozen egg tart liquid.

[0054] Comparative Example 2

[0055] Referring to Example 1, the emulsifier in step 2 is omitted, and the other conditions remain unchanged:

[0056] Step 1: Mix 120 kg of pure milk, 30 kg of egg yolk liquid and 40 kg of L-arabinose, heat in a water bath to 60°C, and slowly stir for 180 minutes to obtain a toffee flavor liquid;

[0057] Step 2: 100 kg soybean oil, 40 kg cream, 0.3 kg salt, 0.1 kg hydroxypropyl methylcellulose, 0.2 kg sodium carboxymethyl cellulose, 0.05 kg xanthan gum, and 80 kg water are dissolved and dispersed evenly by using a vacuum emulsifying device, and the temperature is raised to 65-68° C. to prepare an oil-water mixture;

[0058] Step 3: Mix the toffee flavor liquid, the oil-water mixture and 60 kg of whole egg liquid;

[0059] Step 4: Heat the liquid to 66°C and sterilize for 30 minutes;

[0060] Step 5: The feed liquid is homogenized in two stages, with the first stage pressure at 20 MPa and the second stage pressure at 10 MPa;

[0061] Step 6: The homogenized liquid is quickly cooled to below 10°C, and quickly frozen at -38°C, and stored at -18°C to obtain frozen egg tart liquid.

[0062] Comparative Example 3

[0063] Referring to the formula in Example 1, instead of subjecting some materials to Maillard reaction in advance, all the raw materials are blended at once:

[0064] Formula: 120Kg milk, 30Kg egg yolk liquid, 40kg L-arabinose, 100kg soybean oil, 40Kg cream, 60Kg egg liquid, 0.3kg salt, 0.1kg Span 60, 0.3Kg Tween 60, 0.1kg mono- and di-glycerol stearate, 0.1kg perhydroxypropyl methylcellulose, 0.2kg sodium carboxymethyl cellulose, 0.05kg xanthan gum, and 80kg water.

[0065] Step 1: Use vacuum emulsification equipment to dissolve and disperse all materials evenly, and heat to 65-68℃;

[0066] Step 2: 66℃, sterilize for 30min;

[0067] Step 3: The feed liquid is subjected to secondary homogenization, with the primary pressure being 20MPa and the secondary pressure being 10MPa;

[0068] Step 4: The homogenized liquid is quickly cooled to below 10°C, and quickly frozen at -38°C, and stored at -18°C to obtain frozen egg tart liquid.

[0069] Evaluation method 1: sensory comparison

[0070] Sensory evaluation criteria:

[0071]

[0072]

[0073] The egg tart liquid obtained in each embodiment and comparative example was thawed, poured into a commercially available egg tart crust, filled to 80% to 90%, and baked at 200°C for 18 minutes to obtain egg tart products for comparison. The results are shown in Table 1 and Figure 1 shown.

[0074] Table 1

[0075]

[0076] Evaluation method 2: freeze-thaw and baking of emulsion

[0077] The stability of the liquid was compared by comparing the uniformity of the emulsion and the baked structure after repeated freezing and thawing; the repeated freezing and thawing conditions were to thaw the product frozen at -18℃ in a 20℃ water bath for 3h (center temperature around 10℃), repeated 5 times. Pour into the same commercially available egg tart crust, fill 80% to 90%, bake at 200℃ for 18 minutes, and obtain egg tart products for comparison.

[0078] The emulsion was frozen and thawed and the baking state was compared. The results are shown in Table 2 and Figure 2 shown.

[0079] Table 2

[0080]

[0081]

[0082] After five freeze-thaw cycles of destructive testing, the viscosity and particle size of the emulsions of Examples 1 and 2 were stable; the viscosity and particle size of the emulsion of Comparative Example 1 increased, resulting in a large number of pores after baking, affecting the sensory organs and flavor.

[0083] Evaluation method 3: Shelf life test

[0084] The obtained frozen egg tart liquid was stored for 18 months and then thawed to measure the viscosity of the corresponding emulsion; and the final egg tart product was prepared according to the same method as above and its sensory evaluation was measured. The results are shown in Table 3.

[0085] If the emulsion becomes uneven, precipitation occurs, and the flavor changes significantly, it is spoiled.

[0086] Table 3

[0087] Example 1 Example 2 Commercially available products 18 months later normal normal Deterioration

[0088] The commercially available product is frozen egg tart liquid purchased in a supermarket, and the shelf life of the commercially available product is only 8-9 days, while the shelf life of the product in the embodiment of the present invention is increased by 50% compared with the commercial product.

[0089] Comparative Example 4 Screening of specific emulsifier types

[0090] Referring to Example 1, the emulsifier composition was adjusted, and the other components remained unchanged to prepare the corresponding frozen egg tart liquid.

[0091] The freeze-thaw stability of the obtained frozen egg tart liquid was tested according to evaluation method 2. The results are shown in Table 4.

[0092] Table 4

[0093]

[0094]

[0095] It can be seen that the present invention, based on the specific selection of the emulsifier system of "Span 60+Tween 60+mono- and di-glycerol stearate", can obtain a frozen egg tart liquid with better flavor and better freeze-thaw stability.

[0096] Comparative Example 5 Screening of specific emulsifier dosage ratio

[0097] Referring to Example 1, the total amount of emulsifier remains unchanged, the ratio of the three components in the emulsifier is adjusted, and the other components remain unchanged to prepare the corresponding frozen egg tart liquid.

[0098] The freeze-thaw stability of the obtained frozen egg tart liquid was tested according to evaluation method 2. The results are shown in Table 5.

[0099] Table 5

[0100]

[0101]

[0102] It can be seen that the combination ratio of Span 60+Tween 60+mono- and di-stearate of glycerol in the emulsifier system of the present invention has a significant effect on the flavor and freeze-thaw stability of the egg tart liquid product. Only when Tween 60 accounts for a large proportion and Span 60 and mono- and di-stearate of glycerol account for an equal proportion, the optimal product can be obtained.

[0103] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. A toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid, characterized in that: The egg liquid for frozen egg tarts is prepared from the following raw materials in weight proportion: 60-70 parts of whole egg liquid, 25-35 parts of egg yolk liquid, 80-120 parts of vegetable oil, 40-45 parts of cream, 40-45 parts of arabinose, 0.1-0.3 parts of salt, 0.3-1.6 parts of emulsifier, 0.3-0.6 parts of thickener, 90-140 parts of milk and 60-110 parts of water.

2. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 1, characterized in that, The emulsifier is a combination system of Span 60, Tween 60, and mono- and di-glyceryl stearate.

3. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 2, characterized in that, The weight ratio of each component in the emulsifier is: 0.1-0.3 part of Span 60, 0.1-1 part of Tween 60, and 0.1-0.3 part of mono- and di-glycerol stearate.

4. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 2, characterized in that, The ratio of Span 60, Tween 60, and mono- and di-glycerol stearates in the emulsifier is 1:(2-3):

1.

5. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 2, characterized in that, The thickener is selected from any one or more of the following combinations: hydroxypropyl methylcellulose, sodium carboxymethyl cellulose, xanthan gum, carrageenan, locust bean gum, guar gum, agar, pectin, sodium alginate, gelatin, gellan gum, and gum arabic.

6. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 1, characterized in that, The thickener may specifically be a combination system of hydroxypropyl methylcellulose, sodium carboxymethyl cellulose and xanthan gum; the weight ratio of each component in the thickener is: 0.1 part of hydroxypropyl methylcellulose, 0.2 part of sodium carboxymethyl cellulose and 0.05 part of xanthan gum.

7. The toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to claim 1, characterized in that, The vegetable oil is selected from any one or more of the following combinations: soybean oil, palm oil, palm kernel oil, coconut oil, rapeseed oil, sunflower seed oil, corn oil, peanut oil, milk fat, olive oil, and tea seed oil. In one embodiment of the present invention, the mass ratio of milk, egg yolk liquid and L-arabinose is 3-4:1:1-1.

3.

8. A method for preparing the toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to any one of claims 1 to 7, characterized in that: The steps include: (1) According to the weight ratio of any one of claims 1 to 7, milk, egg yolk liquid and L-arabinose are mixed to perform Maillard reaction to obtain a toffee liquid; (2) Mixing vegetable oil, cream, salt, emulsifier, thickener and water according to the weight ratio of any one of claims 1 to 7, dissolving and dispersing them uniformly, and heating them to 65-68° C. to prepare an oil-water mixture; (3) according to the weight proportion in any one of claims 1 to 7, the whole egg liquid is mixed with the toffee liquid obtained in step (1) and the oil-water mixture obtained in step (2), and pasteurized at 65-68° C. for 20 to 30 min.

9. The method according to claim 8, characterized in that The method further comprises: performing secondary homogenization on the sterilized mixed liquid, with the primary pressure being 20-25 MPa and the secondary pressure being 10-15 MPa, precooling the obtained mixed liquid after homogenization to 5-10° C., and then placing it at -38--18° C. for quick freezing and freezing, so as to obtain a toffee-flavored long-acting freeze-thaw stable frozen egg tart-specific egg liquid.

10. Application of the toffee-flavored long-acting freeze-thaw stable frozen egg tart special egg liquid according to any one of claims 1 to 7 in food processing.

Images