阅读说明：本技术 一种膨化食品及其制备方法 (Puffed food and preparation method thereof ) 是由 林亲录 王青云 王素燕 白婕 许东 于 2021-10-22 设计创作，主要内容包括：本发明提供一种膨化食品及其制备方法,制备方法包括：将含淀粉类食材经预熟化或预糊化处理后,加入酵母菌发酵浓缩物,混匀后经成型机成型,再经低温真空油炸膨化、脱油,得到膨化食品；所述酵母菌发酵浓缩物的加入量为含淀粉类食材质量的5％-20％。本发明可有效控制油炸膨化食品的过氧化值,从而避免出现油炸膨化食品过氧化值超标的问题,以及解决油炸膨化食品因过氧化物含量高,长期摄入可能产生危害的问题。同时,酵母菌发酵产物中富含酵母蛋白和B族维生素,可改善传统油炸膨化食品营养成分单一的缺陷。此外,采用低温真空油炸技术,最大限度减少了膨化食品中营养成分的损失。(The invention provides a puffed food and a preparation method thereof, wherein the preparation method comprises the following steps: pre-curing or pre-gelatinizing starch-containing food materials, adding yeast fermentation concentrate, uniformly mixing, molding by a molding machine, and performing low-temperature vacuum frying puffing and deoiling to obtain puffed food; the addition amount of the yeast fermentation concentrate is 5-20% of the mass of the starch-containing food material. The method can effectively control the peroxide value of the fried puffed food, thereby avoiding the problem that the peroxide value of the fried puffed food exceeds the standard and solving the problem that the fried puffed food is possibly damaged after being taken for a long time due to high peroxide content. Meanwhile, the yeast fermentation product is rich in yeast protein and B vitamins, and the defect of single nutrient content of the traditional fried puffed food can be overcome. In addition, the low-temperature vacuum frying technology is adopted, so that the loss of nutrient components in the puffed food is reduced to the maximum extent.)

1. A method of preparing an expanded food product comprising:

pre-curing or pre-gelatinizing starch-containing food materials, adding yeast fermentation concentrate, uniformly mixing, molding by a molding machine, and performing low-temperature vacuum frying puffing and deoiling to obtain puffed food;

the addition amount of the yeast fermentation concentrate is 5-20% of the mass of the starch-containing food material.

2. The method of preparing an expanded food product according to claim 1, wherein the yeast fermentation concentrate is prepared by:

inoculating the activated yeast liquid strain into a first liquid culture medium, culturing for 24-120h under aerobic condition, breaking the cell wall of the culture by yeast cells, and performing vacuum evaporation and concentration to obtain yeast fermentation concentrate, wherein the inoculation amount of the strain is 3-8 mL/100 mL of the first liquid culture medium.

3. The method of claim 2, wherein the yeast is kluyveromyces marxianus or candida utilis.

4. The method of preparing an expanded food product according to claim 2, wherein the first liquid medium is a wort liquid medium, and the content of malt extract in the wort liquid medium is 0.20 to 0.25 g/mL.

5. The method of preparing an expanded food product according to any one of claims 1 to 4, further comprising, after the low temperature vacuum frying: adding dietary fiber and/or active lactobacillus fermentation product lyophilized powder, mixing, and packaging;

the dietary fiber is functional oligosaccharide or dietary fiber powder.

6. The method for preparing an expanded food according to claim 5, wherein the active lactobacillus fermentation product freeze-dried powder is prepared by the following steps:

inoculating the lactobacillus powder into a second liquid culture medium, wherein the inoculation amount is 0.1-0.5g of the lactobacillus powder per 100mL of the second liquid culture medium, culturing for 6-40h at 38-45 ℃ in an anaerobic environment, and freeze-drying to obtain the active lactobacillus fermentation product freeze-dried powder.

7. The method of claim 6, wherein the lactic acid bacteria is one or more of Bifidobacterium animalis, Bifidobacterium lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus paracasei, lactococcus lactis subspecies lactis, lactococcus lactis subspecies cremoris, Leuconostoc mesenteroides, lactococcus lactis diacetyl subspecies.

8. The method of producing an expanded food according to any one of claims 1 to 4, wherein the starch-containing food material is a cereal-based food material or a potato-based food material.

9. The method for preparing an expanded food according to any one of claims 1 to 4, wherein the vacuum degree of the vacuum low-temperature frying is 0.05 to 0.09MPa, the frying temperature is 50 to 100 ℃, and the frying time is 10s to 6 min.

10. An expanded food product obtainable by the process according to any one of claims 1 to 9.

Technical Field

The invention particularly relates to a puffed food and a preparation method thereof.

Background

Puffed food has been popular among consumers, especially children, for a long time because of its varied appearance, delicious taste and crispy mouthfeel. The puffed food is classified into extruded puffed food, baked puffed food, fried puffed food and the like according to the processing mode. Wherein, the fried puffed food usually adopts a secondary puffing process with oil as a heating medium, so that the fried puffed food has better mouthfeel, color and fragrance, has a larger consumer group and occupies the mainstream position of the puffed food market. With the increasing awareness of people's consumption, the nutrition and health of food have become a major concern for consumers to shop. The existing fried puffed food generally has the three problems of high fat, high heat and high additive. The national supervision and spot inspection results of fried snack foods and puffed foods also show that the foods are easy to have the problems of unqualified items such as peroxide value, carbonyl value and the like, overproof residual quantity of aluminum and the like. Various studies have shown that the preference for fried puffed foods is closely related to the obesity of children and teenagers; meanwhile, long-term consumption of food with high over-oxidation value can affect the health of heart and cerebral vessels and easily cause chronic diseases such as arteriosclerosis, tumors and the like; and long-term intake of aluminum can damage brain nerve cells, affect the intelligence development of children and cause memory loss.

From the aspect of nutrition, most of puffed foods take starch substances as main raw materials, have single nutritional ingredients and cannot meet the nutritional requirements of human bodies. The fried puffed food has the characteristics of high oil and high sugar, and does not meet the low-calorie diet requirements of modern people. The existing fried puffed food mostly adopts a high-temperature frying process, and harmful substances such as acrylamide and the like generated in the high-temperature frying process attract the general attention of consumers.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a preparation method of puffed food for effectively controlling the peroxide value of fried puffed food and improving the nutrient content of traditional fried puffed food aiming at the defects in the prior art, and correspondingly provide the puffed food prepared by the preparation method.

The technical scheme adopted for solving the technical problem of the invention is as follows:

the invention provides a preparation method of puffed food, which comprises the following steps:

pre-curing or pre-gelatinizing starch-containing food materials, adding yeast fermentation concentrate, uniformly mixing, molding by a molding machine, and performing low-temperature vacuum frying puffing and deoiling to obtain puffed food;

the addition amount of the yeast fermentation concentrate is 5-20% of the mass of the starch-containing food material.

Optionally, the yeast fermentation concentrate is prepared by the following steps:

inoculating the activated yeast liquid strain into a first liquid culture medium, culturing for 24-120h under aerobic condition, breaking the cell wall of the culture by yeast cells, and performing vacuum evaporation and concentration to obtain yeast fermentation concentrate, wherein the inoculation amount of the strain is 3-8 mL/100 mL of the first liquid culture medium.

Optionally, the yeast is Kluyveromyces marxianus (Kluyveromyces marxianus) or Candida utilis (Candida utilis).

Optionally, the first liquid medium is a wort liquid medium, and the malt extract content of the wort liquid medium is 0.20-0.25 g/mL.

Optionally, the method further comprises, after the low-temperature vacuum frying: adding dietary fiber and/or active lactobacillus fermentation product lyophilized powder, mixing, and packaging;

the dietary fiber is functional oligosaccharide or dietary fiber powder.

The functional oligosaccharide belongs to water-soluble dietary fiber. It is preferably one of fructo-oligosaccharide, lactulose-oligosaccharide, xylo-oligosaccharide, and isomaltose oligosaccharide. Research shows that the functional oligosaccharide can promote the proliferation of lactic acid bacteria in intestinal tract.

Optionally, 3-10g dietary fiber is added into per 100g deoiled food, and the mixture is packaged and stored at normal temperature. Or adding 3-10g of mixture of dietary fiber and active lactobacillus fermentation product freeze-dried powder into every 100g of deoiled food, uniformly mixing, packaging, and refrigerating at 0-4 ℃ or storing at normal temperature, wherein in the mixture, the mass ratio of the active lactobacillus fermentation product freeze-dried powder to the dietary fiber is 1: 3-10.

Optionally, the preparation process of the active lactobacillus fermentation product freeze-dried powder is as follows:

inoculating the lactobacillus powder into a second liquid culture medium, wherein the inoculation amount is 0.1-0.5g of the lactobacillus powder per 100mL of the second liquid culture medium, culturing for 6-40h at 38-45 ℃ in an anaerobic environment, and freeze-drying to obtain the active lactobacillus fermentation product freeze-dried powder.

Alternatively, the lactic acid bacterium is one or more species of Bifidobacterium animalis (Bifidobacterium animalis), Bifidobacterium lactis (Bifidobacterium lactis), Bifidobacterium adolescentis (Bifidobacterium adolescentis), Bifidobacterium longum (Bifidobacterium longum), Lactobacillus plantarum (Lactobacillus plantarum), Lactobacillus rhamnosus (Lactobacillus rhamnoides), Lactobacillus bulgaricus (Lactobacillus bulgaricus), Streptococcus thermophilus (Streptococcus thermophilus), Lactobacillus acidophilus (Lactobacillus acidophilus), Lactobacillus paracasei (Lactobacillus paracasei), Lactobacillus lactis (Lactobacillus lactis subsp.

The second liquid culture medium is preferably tomato juice culture medium, and each 100mL tomato juice culture medium contains tomato juice 5.0mL, yeast extract 0.5g, meat extract 1.0g, lactose 2.0g, and glucoseGlucose 0.2g, K₂HPO₄0.2g, sodium acetate 0.5g, pH 6.8.

Optionally, the starch-containing food material is a cereal food material or a potato food material. Preferably potato, sweet potato, rice or brown rice.

Optionally, the vacuum degree of the vacuum low-temperature frying is 0.05-0.09MPa, the frying temperature is 50-100 ℃, and the frying time is 10s-6 min.

And after the frying is finished, carrying out centrifugal deoiling by using a built-in deoiling device, wherein the deoiling time is 1-5 min.

Optionally, the method further comprises the following steps between the forming and the low-temperature vacuum frying: drying the formed product until the water content is 10-30%; the drying temperature is 40-55 ℃, and the drying time is 4-36 h.

The pre-curing or pre-gelatinization is preferably carried out by cooking at 90-100 deg.C for 15-50 min.

The yeast and lactic acid bacteria used in the invention are all commercial strains.

The invention also provides the puffed food prepared by the preparation method.

1. The research of the invention shows that in the process of making the fried puffed food, the yeast fermentation product with 5-20% of the mass of the raw material is added into the raw material before frying, so that the peroxide value of the fried puffed food can be effectively controlled, the problem that the peroxide value of the fried puffed food exceeds the standard is avoided, and the problem that the fried puffed food is possibly harmful after being taken for a long time due to high peroxide content is solved. Meanwhile, the yeast fermentation product is rich in yeast protein and B vitamins, and the defect of single nutrient content of the traditional fried puffed food can be overcome. The yeast is usually used as a fermentation strain in the food processing process, and achieves a fluffy and porous structure through the fermentation effect, and the addition amount of the yeast generally accounts for about 0.5 percent of the mass of the food raw materials; the invention adds a large amount of yeast fermentation products after wall breaking into the raw materials of the puffed food so as to achieve the aims of inhibiting the generation of peroxide and improving nutrition. In addition, the low-temperature vacuum frying technology is adopted, so that the loss of nutrient components in the puffed food is reduced to the maximum extent.

2. The addition of the dietary fiber enriches the nutritional ingredients of the fried puffed food, can promote the proliferation of intestinal probiotics, is beneficial to the prevention of obesity, hyperlipidemia and other modern civilization diseases, and can relieve the problem of obesity caused by preference for eating the fried puffed food.

3. Active probiotics contribute to the health and balance of the intestinal flora. Meanwhile, the lactic acid bacteria have a relieving effect on aluminum poisoning, and can reduce the harm to human bodies caused by aluminum accumulation after the puffed food is taken for a long time.

Detailed Description

The technical solutions in the present invention will be described clearly and completely with reference to specific embodiments, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of the present invention.

A method of preparing an expanded food product comprising:

pre-curing or pre-gelatinizing starch-containing food materials, adding the prepared yeast fermentation concentrate, mixing, molding by a molding machine, drying, puffing by low-temperature vacuum frying, deoiling, adding dietary fiber or active lactobacillus fermentation product freeze-dried powder, mixing, and packaging.

The method specifically comprises the following process steps:

(1) preparing a yeast fermentation product, namely inoculating activated yeast liquid strains into a first liquid culture medium, wherein the inoculation amount is 3-8mL of strains per 100mL of the first liquid culture medium, culturing for 24-120h under an aerobic condition, breaking the walls of yeast cells of the culture by an ultrasonic cell crusher, and performing vacuum evaporation concentration to obtain a yeast fermentation concentrate; wherein the first liquid medium is a wort liquid medium (20-25 g malt extract in 100mL medium), which is commercially available.

(2) Preparation of lactic acid bacteria fermentation product freeze-dried powder lactic acid bacteria powder is inoculated into a second liquid culture medium, and the inoculation amount is 0.1-0.5g bacteria powder/100 mL second liquid culture medium. Culturing in an anaerobic incubator at 38-45 deg.C for 6-40h, and freeze drying to obtain lactobacillus fermentation product lyophilized powder; the number of viable bacteria in each gram of freeze-dried powder is more than or equal to 10 hundred million CFU.

(3) The starch-containing food material is pretreated correspondingly according to the conventional method for preparing puffed food, and then is steamed at 90-100 deg.C for 15-50 min.

(4) And (3) cooling the steamed raw materials, and adding the yeast fermentation concentrate prepared in the step (1), wherein the adding amount of the yeast fermentation concentrate accounts for 5-20% of the mass of the main raw materials. Mixing, and making into strip, sheet or other shapes.

(5) Drying the formed product until the water content is 10-30%; drying at 40-55 deg.C for 4-36 h;

(6) and (5) frying and puffing the product processed in the step (5) at a low temperature in vacuum, wherein the frying temperature is controlled to be 50-100 ℃, and the frying time is 30s-6 min. After the frying is finished, carrying out centrifugal deoiling by using an internal deoiling device, wherein the deoiling time is 1-5 min;

(7) adding 3-10g of the mixture of the lactobacillus fermentation product freeze-dried powder and the dietary fiber prepared in the step (2) into every 100g of the deoiled product, uniformly mixing, packaging, and refrigerating at 0-4 ℃ or storing at normal temperature; or adding 3-10g dietary fiber into per 100g product, mixing, packaging, and storing at room temperature.

Wherein the dietary fiber is functional oligosaccharide or dietary fiber powder.

The functional oligosaccharide belongs to water-soluble dietary fiber. It is preferably one of fructo-oligosaccharide, lactulose-oligosaccharide, xylo-oligosaccharide, and isomaltose oligosaccharide.

As a specific technical scheme, in the step (1), the yeast is preferably Kluyveromyces marxianus (Kluyveromyces marxianus) or Candida utilis (Candida utilis);

as a specific technical scheme, in the step (2), the Lactobacillus is preferably Bifidobacterium animalis (Bifidobacterium animalis), Bifidobacterium lactis (Bifidobacterium lactis), Bifidobacterium adolescentis (Bifidobacterium adolescentis), Bifidobacterium longum (Bifidobacterium longum), Lactobacillus plantarum (Lactobacillus plantarum), Lactobacillus rhamnosus (Lactobacillus rhamnoides), and Lactobacillus bulgaricus (L)One or more of Lactobacillus bulgaricus, Streptococcus thermophilus (Streptococcus thermophilus), Lactobacillus acidophilus (Lactobacillus acidophilus), Lactobacillus paracasei (Lactobacillus paracasei), Lactococcus lactis subsp. The second liquid culture medium is preferably tomato juice culture medium (each 100mL culture medium contains tomato juice 5.0mL, yeast extract 0.5g, meat extract 1.0g, lactose 2.0g, glucose 0.2g, and K₂HPO40.2g, sodium acetate 0.5g, pH 6.8);

according to a specific technical scheme, in the step (3), the starch-containing food material is a cereal raw material or a potato raw material, preferably potato, rice or brown rice.

As a specific technical scheme, in the mixture of the lactobacillus fermentation product freeze-dried powder and the dietary fiber in the step (7), the mass ratio of the lactobacillus fermentation product freeze-dried powder to the dietary fiber is 1: 3-10. The functional oligosaccharide is preferably one of fructo-oligosaccharide, lactulose-oligosaccharide, xylo-oligosaccharide, and isomaltose oligosaccharide.

Example 1:

the fresh potatoes, the Kluyveromyces marxianus, the lactic acid bacteria powder and the fructo-oligosaccharide in the embodiment are all sold in the market, the probiotics contained in the lactic acid bacteria powder are bifidobacterium animalis, streptococcus thermophilus and lactobacillus paracasei, and the mass ratio of the three bacteria is 1: 0.5-2.

The embodiment comprises the following steps:

(1) preparation of yeast fermentation product refrigerated kluyveromyces marxianus is inoculated into a wort liquid culture medium for shake flask activation, after activation is carried out for 24 hours at 28 ℃ and 160r/min, the kluyveromyces marxianus is inoculated into an aerobic fermentation tank for fermentation culture, the fermentation culture medium is the wort culture medium, the dissolved oxygen is set to be 30%, the fermentation temperature is 30 ℃, and the fermentation time is 96 hours. After fermentation, breaking cell wall of the obtained fermentation product by using an ultrasonic wall breaking pulverizer, and performing vacuum evaporation concentration to 30% of the original volume at 50 ℃ and under the vacuum degree of 0.015MPa to obtain a yeast fermentation concentrate;

(2) preparation of lactic acid bacteria fermentation product freeze-dried powder lactic acid bacteria powder is inoculated into a tomato juice culture medium, and the inoculation amount is 0.1g of bacteria powder per 100mL of tomato juice culture medium. Culturing in 42 deg.C anaerobic culture box for 26h, and freeze drying to obtain lactobacillus fermentation product lyophilized powder. The number of viable bacteria in each gram of freeze-dried powder is more than or equal to 10 hundred million CFU;

(3) cleaning fresh potato, peeling, pulping, filtering to remove water, making into dough, and steaming with boiling water for 40 min;

(4) cooling the cooked potato dough to a temperature below 40 ℃, and adding the yeast fermentation concentrate prepared in step (1) in an amount of 15g yeast fermentation concentrate per 100g potato dough. After mixing uniformly, rolling and forming to prepare a sheet with the thickness of about 2 mm;

(5) drying the formed product in a hot air dryer at 50 ℃ for 10h until the water content is 15%;

(6) frying the product treated in the step (4) at a low temperature of 90 ℃ for 1.5min in vacuum, and after frying, centrifugally deoiling for 1 min;

(7) adding 5g of mixture of lactobacillus fermentation product freeze-dried powder and fructo-oligosaccharide into every 100g of deoiled product, wherein the mass ratio of the lactobacillus fermentation product freeze-dried powder to the fructo-oligosaccharide is 1: 4, uniformly mixing, packaging, and refrigerating at 0-4 ℃ or storing at normal temperature;

the puffed potato chips prepared by the embodiment have natural yeast fragrance, slightly sweet and sour taste, and are crispy and delicious. Every 100g of potato chips contain not less than 10 hundred million CFU lactic acid bacteria. The peroxide value of the puffed potato chip is 0.06g/100g when the puffed potato chip is packaged, and the peroxide value is almost unchanged after the puffed potato chip is refrigerated and stored for 2 months; the peroxide value after 2 months of storage at normal temperature is 0.08g/100 g.

GB17401-2014 specifies that the limit index of the peroxide value of the oil-containing puffed food is less than or equal to 0.25g/100 g. The peroxide value of the fried puffed potato chips produced by the conventional method is usually 0.15-0.25g/100g in the shelf life, and the spot inspection result of related national departments shows that the peroxide value of the partially fried puffed food is even as high as 1.4g/100g and exceeds the limit index by more than 4 times.

Example 2

The candida utilis, potato flakes, potato starch, rice flour and dietary fiber powder used in this example are all commercially available.

(1) Preparation of yeast fermentation product refrigerated candida utilis is inoculated into a wort liquid culture medium for shake flask activation, after activation for 20 hours under the conditions of 28 ℃ and 160r/min, the candida utilis is inoculated into an aerobic fermentation tank for fermentation culture, the fermentation culture medium is a wort culture medium, the dissolved oxygen is set to be 30 percent, the fermentation temperature is 30 ℃, and the fermentation time is 96 hours. After fermentation, breaking the yeast cell wall of the obtained fermentation product by using an ultrasonic wall breaking pulverizer, and performing vacuum evaporation concentration to 40% of the original volume at 50 ℃ and under the vacuum degree of 0.015MPa to obtain a yeast fermentation concentrate;

(2) weighing the whole potato powder, the potato starch and the rice flour according to the mass ratio of 5: 1: 2, uniformly mixing, and steaming the dry powder in a steamer for 30 min;

(3) cooling the steamed raw materials to below 40 ℃, adding 10g of the yeast fermentation concentrate prepared in the step (1) into every 100g of the raw materials, uniformly mixing, adding a proper amount of water to prepare smooth dough, and rolling and molding the dough to prepare strips with the cross sections of 4mm in length and width;

(4) vacuum drying the formed product at 45 ℃ until the water content is 18%;

(5) frying the product treated in the step (4) at a low temperature of 100 ℃ for 2min in vacuum, and then carrying out centrifugal deoiling for 2min by using a built-in deoiling device;

(6) adding 8g of dietary fiber powder into every 100g of the deoiled product, uniformly mixing, packaging and storing at normal temperature.

The puffed potato chips prepared by the embodiment have natural yeast fragrance and are crisp and delicious. The peroxide value of the puffed potato chips is 0.07g/100g when the puffed potato chips are packaged, and the peroxide value of the puffed potato chips after being stored for 2 months is 0.10g/100 g. The peroxide value of the fried puffed potato chips produced by the conventional method in the shelf life is usually 0.15-0.25g/100 g. In part of puffed food found by market spot check, the peroxide value exceeds the national limit index (0.25g/100g) value by more than 4 times.

Example 3

The candida utilis, the lactic acid bacteria powder, the fresh sweet potatoes, the rice flour and the isomaltooligosaccharide used in the embodiment are all commercially available. The lactobacillus powder contains probiotics such as Bifidobacterium lactis, Lactobacillus rhamnosus and Lactobacillus acidophilus.

(1) Preparation of yeast fermentation product refrigerated Candida utilis is inoculated into a wort liquid culture medium for shake flask activation, after activation for 20 hours at 28 ℃ and 160r/min, the Candida utilis is inoculated into an aerobic fermentation tank for fermentation culture, the fermentation culture medium is a wort culture medium, the dissolved oxygen is set to be 30 percent, the fermentation temperature is 28 ℃, and the fermentation time is 110 hours. After fermentation, breaking the yeast cell wall of the obtained fermentation product by using an ultrasonic wall breaking pulverizer, and performing vacuum evaporation concentration at 45 ℃ to 60% of the original volume to obtain a yeast fermentation concentrate;

(2) preparation of lactic acid bacteria fermentation product freeze-dried powder lactic acid bacteria powder is inoculated into a tomato juice culture medium, and the inoculation amount is 0.1g of bacteria powder per 100mL of tomato juice culture medium. Culturing in an anaerobic incubator at 39 deg.C for 30h, and freeze drying to obtain lactobacillus fermentation product lyophilized powder. The number of viable bacteria in each gram of freeze-dried powder is more than or equal to 10 hundred million CFU;

(3) peeling fresh sweet potato, steaming for about 40min until the sweet potato is cooked, and mashing into mashed potato by a mashing machine;

(4) cooling potato mash to below 45 deg.C, adding yeast fermented concentrate and rice flour according to the mass ratio of potato mash, yeast fermented concentrate and rice flour of 10: 1: 2, and stirring in stirrer. Pressing into square or round pieces with thickness of 2-3mm by a roller press or a die;

(5) drying the formed product by hot air at 55 ℃ until the moisture content is about 12%;

(6) frying the product treated in the step (4) for 45s at a low temperature of 95 ℃ in vacuum, and then performing centrifugal deoiling for 1min by using a built-in deoiling device;

(7) adding 8g of the mixture of the freeze-dried powder of the lactic acid bacteria fermentation product prepared in the step (2) and isomaltooligosaccharide into every 100g of the deoiled product, wherein the mass ratio of the freeze-dried powder of the lactic acid bacteria fermentation product to the isomaltooligosaccharide in the mixture is 1: 5, uniformly mixing, packaging, and refrigerating at 0-4 ℃ or storing at normal temperature.

The puffed potato chips prepared by the embodiment have natural yeast fragrance, sour and sweet taste and are crispy and delicious. The peroxide value of the puffed potato chip is 0.05g/100g when the puffed potato chip is packaged, the peroxide value is not obviously changed after the puffed potato chip is stored for two months under refrigeration, and the peroxide value is 0.09g/100g after the puffed potato chip is stored for 2 months at normal temperature.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.