CN104431868A - Preparation method of purple potato snack rich in anthocyanin - Google Patents

Abstract

A preparation method of purple sweet potato snack food rich in anthocyanins, comprising the following steps: material selection, cleaning, steaming, peeling, chopping and crushing, batching, shaping, freeze-drying, vacuum sealing and bagging, etc. The water content in the obtained food is between 3% and 5%, and every 100g (dry basis) of the snack food contains more than 200mg of anthocyanin. The beneficial effects of the present invention are as follows: 1. The method of the present invention is to utilize purple sweet potato to produce a kind of purple sweet potato snack food rich in anthocyanins, which provides a new way for the development and utilization of purple sweet potato, the processing method is simple, edible Convenient and practical. 2. adopt this method to adopt vacuum freeze-drying dehydration to produce purple sweet potato leisure food, compare with existing processing method, retain original anthocyanin to the greatest extent, the anthocyanin content in every 100g purple sweet potato instant food is greater than 200mg.

Description

A kind of preparation method of purple sweet potato snack food rich in anthocyanins

technical field

The invention belongs to the field of deep processing of agricultural products, and more specifically relates to a preparation method of purple sweet potato snack food rich in anthocyanins.

Background technique

With the acceleration of people's life rhythm, living habits are constantly changing. Staying up late, working overtime, drinking and socializing, and lack of exercise lead to an increasing prevalence of metabolic diseases, cardiovascular diseases, and alcoholic liver disease. There is a trend of rejuvenation. In addition, with the change of working environment and living environment, various sources of radiation such as computers and TVs are constantly infringing on people's eyesight and health. Can you improve the health problems caused by working environment and living habits through diet adjustment?

Studies have found that purple sweet potatoes are rich in anthocyanins, which have preventive and therapeutic effects on many diseases, including: (1) Helps prevent many diseases related to free radicals, including cancer, heart disease, premature aging and arthritis; (2) reduce the occurrence of heart disease and stroke by preventing platelet aggregation caused by stress and smoking; (3) strengthen the immune system to resist carcinogens; (4) reduce the number and duration of colds (5) has anti-mutagenic function to reduce the formation of carcinogens; (6) has anti-inflammatory effect, thus preventing inflammation including arthritis and swelling; (7) relieves hay fever and other allergies; (8) )Enhance the elasticity of arteries, veins and capillaries; (9) protect the inner wall of arteries; (10) maintain the normal flexibility of blood cells to help red blood cells pass through tiny capillaries, thus enhancing the blood circulation of the whole body and providing health benefits for all parts of the body. Organs and systems bring direct benefits and enhance cell viability; (11) relax blood vessels to promote blood flow and prevent hypertension (hypertensive effect); (12) prevent angiotensin-converting enzymes released from the kidneys Increased blood pressure (another blood pressure-lowering effect); (13) Acts as a barrier to protect brain cells from amyloid-beta protein formation, glutamate toxicity, and free radical attack, thereby preventing Alzheimer's disease ; (14) Make the skin smooth and elastic by inhibiting elastase and collagenase, and prevent skin damage caused by excessive sun exposure from the inside and outside at the same time; (15) Anthocyanins also have anti-radiation The color of anthocyanins will change due to different pH values. Most anthocyanins have good light, heat, and pH stability. For white-collar workers or people who have been exposed to the sun and electric radiation for a long time, anthocyanins (16) Anthocyanins can promote the regeneration of rhodopsin in retinal cells, prevent myopia and improve vision.

The deep processing of purple sweet potato food usually adopts steaming and cooking, and then carries out seasoning, sterilization and antiseptic treatment, such as Chinese patent CN102266024, a kind of preparation method of convenient and instant purple sweet potato food, adopts first purple sweet potato to be cleaned and then steamed and processed, Carry out food seasoning, high-temperature sterilization, although the obtained purple sweet potato food has rich taste, but wherein the content of anthocyanin does not improve, so the nutritional value of this food is lower.

Therefore, the present invention uses purple sweet potato as raw material, adopts the mode of freezing and dehydration, keeps purple sweet potato anthocyanin as far as possible, prepares a kind of snack food rich in anthocyanin, makes consumer work, study, life spare time , intake of anthocyanins with multiple preventive functions, thereby alleviating or preventing related diseases.

Contents of the invention

In order to solve the disadvantages of low anthocyanin content and the addition of a large amount of preservatives in the existing purple potato leisure food, the present invention provides a preparation method of purple potato leisure food with high anthocyanin content.

The technical scheme of the present invention is a kind of preparation method of the purple sweet potato leisure food that is rich in anthocyanin, comprises the following steps:

(1) Material selection and cleaning: select fresh purple sweet potatoes without rot, mildew, and no cracks, use clean water to wash off the sediment on the surface of the purple sweet potatoes, and clean the sediment in the depressions with a brush;

(2) Steaming and peeling: After the purple sweet potatoes are cleaned, drain the water and arrange them in a plate. Before steaming, the steamer needs to be preheated. After the purple sweet potatoes are steamed, cool them at room temperature, cool to room temperature, and peel off the skin of the purple sweet potatoes. ;

(3) Chopping and crushing, ingredients: put the peeled cooked purple sweet potato into a chopping machine and crush it into purple sweet potato puree, add sucrose or no-calorie sugar during the chopping and mixing process;

(4) Shaping, freeze-drying: put the purple sweet potato mash into a molding machine to shape, put it into a refrigerator for pre-freezing, and use a freeze dryer to freeze-dry;

(5) Vacuum-sealed bagging: place the freeze-dried product in a bag, and put it in a vacuum-sealed bag.

In the step (2), the steaming temperature is greater than or equal to 100° C., which can be steamed under normal pressure or under high pressure. The purpose of steaming is to inactivate polyphenol oxidase in purple sweet potato and prevent color change in later processing. In addition, before steaming, the purple sweet potato should be kept intact without damage to reduce the loss of purple sweet potato anthocyanins.

In the step (3), crushed sucrose is added in the chopping process, and the added amount is 8-12% of the mass of the purple sweet potato, and the sucrose is white granulated sugar or soft white sugar.

In the step (3), the calorie-free sugar added in the chopping process is stevioside or xylitol, and the additive amount of stevioside is 0.06-0.08% of the mass of the purple sweet potato. The addition amount of xylitol is 8-12% of the quality of purple sweet potato.

In the step (4), the molding machine is in the shape of a circular sheet, a square sheet or an irregular sheet, and the thickness of the sheet is 2-5mm.

The processing method adopts vacuum freeze-drying, the purpose is to keep the anthocyanins of purple sweet potato to the greatest extent. Freeze-drying can adopt a vacuum freeze-drying machine or other freeze-drying equipment, and the moisture content of the dried product is between 3% and 5%.

The preparation method of the purple sweet potato snack food rich in anthocyanin is characterized in that, every 100g (dry basis) of the snack food contains more than 200mg of anthocyanin. The anthocyanins in the purple potato snack food can be the anthocyanins contained in the purple potato itself, or can be added with blueberry anthocyanins or purple carrot anthocyanins and anthocyanins from other sources.

The beneficial effects of the present invention are as follows: 1. The method of the present invention is to utilize purple sweet potato to produce a kind of purple sweet potato snack food rich in anthocyanins, which provides a new way for the development and utilization of purple sweet potato, the processing method is simple, edible Convenient and practical.

2. adopt this method to adopt vacuum freeze-drying dehydration to produce purple sweet potato leisure food, compare with existing processing method, retain original anthocyanin to the greatest extent, the anthocyanin content in every 100g purple sweet potato instant food is greater than 200mg.

Detailed ways

The present invention will be described in detail below through examples.

Example 1:

1. Material selection and cleaning: Select fresh purple sweet potatoes without rot, mildew, or cracks, use clean water to wash off the sediment on the surface of the purple sweet potatoes, and clean the sediment in the depressions with a brush.

2. Steaming and peeling: After cleaning the purple potatoes, drain all the water and arrange them in a plate. Before steaming, the steamer needs to be preheated. The steaming temperature is 95-120°C, the steaming time is 15-20 minutes, and the steam pressure is 0.1-2. 0.2Mpa. After the purple sweet potato is steamed, cool it at room temperature, cool to room temperature, and peel off the skin of the purple sweet potato.

3. Chopping and crushing, ingredients: Put the peeled cooked purple sweet potato into a chopping machine and crush it into purple potato puree. During the chopping and mixing process, add white sugar. The amount of white sugar added is 100kg of purple potato pulp plus 10kg of white sugar.

4. Shaping and freeze-drying: Put the purple sweet potato puree into a mold to shape it, put it into a refrigerator for pre-freezing, and use a freeze dryer to freeze-dry it. The moisture content of the final freeze-dried product is between 3% and 5%.

5. Vacuum seal the freeze-dried product with a plastic bag.

6. Determination of anthocyanin content and water content: the change of anthocyanin content in purple sweet potato in different forms was measured by pH differential method. The pH differential method is as follows:

(1) The hue and chroma of anthocyanins changed with the pH value, but the characteristic spectrum of the interfering substances did not change with the pH. At pH 1, anthocyanins exist in the form of red 2-phenylbenzopyran, and at pH 4.5, anthocyanins exist in the form of colorless methanol pseudobase. Combined with the Lambert-Beer law, it can be concluded that at two different pH values, the difference in absorbance of anthocyanin solution is proportional to the content of anthocyanin.

(2) Preparation of buffer:

Buffer solution with pH 1.0: Accurately weigh 1.49g KCl and dilute to 100mL with distilled water. Accurately measure 1.7mL of hydrochloric acid (analytical grade) and dilute to 100mL with distilled water to prepare a 0.2mol/L hydrochloric acid solution, mix the KCl solution and the hydrochloric acid solution at a ratio of 25:67, and adjust the pH to 1.0±0.1 with the KCl solution.

Buffer with a pH of 4.5: Accurately weigh 1.64g of NaAc and dilute to 100mL with distilled water, and adjust the pH to 4.5±0.1 with the above-mentioned 0.2mol/L hydrochloric acid.

(3) Determination formula of anthocyanin content in purple sweet potato:

Anthocyanin content (mg/L)=(A×MW×DF×1000)/(ε×1)

In the formula: A──absorbance, A=(A525nm pH1.0-A700nm pH1.0)-(A525nm pH4.5-A700nmpH4.5);

ε──cyanidin-3-glucoside extinction coefficient, 26900;

DF - dilution factor;

MW──Molecular weight of cyanidin-3-glucoside, 449.2;

Note: Use distilled water as a reference; use A700nm to eliminate the influence of sample liquid turbidity.

The anthocyanin content and moisture content of purple sweet potato in different forms are as follows:

form Anthocyanin content (mg/g) Moisture content% Fresh Purple Potato 1.02 68.97 Steamed Purple Potato 0.87 69.12 Purple Potato Snack Food 2.2 3.16

Example 2

1. Material selection and cleaning: Select fresh purple sweet potatoes without rot, mildew, or cracks, use clean water to wash off the sediment on the surface of the purple sweet potatoes, and clean the sediment in the depressions with a brush.

2. Steaming and peeling: After cleaning the purple potatoes, drain all the water and arrange them in a plate. Before steaming, the steamer needs to be preheated. The steaming temperature is 95-120°C, the steaming time is 15-20 minutes, and the steam pressure is 0.1-2. 0.2Mpa. After the purple sweet potato is steamed, cool it at room temperature, cool it to room temperature, and remove the skin.

3. Chopping and crushing, ingredients: peeled cooked purple sweet potatoes. Put it into a chopping machine and crush it into purple sweet potato mash, add stevioside during the chopping and mixing process, and add 0.035kg to 100kg of purple potato pulp.

4. Shaping and freeze-drying: Put the purple sweet potato puree into a mold to shape it, put it into a refrigerator for pre-freezing, and use a freeze dryer to freeze-dry it. The moisture content of the final freeze-dried product is between 3% and 5%.

5. Vacuum seal the freeze-dried product with a plastic bag.

6. According to the detection method of item 6 in embodiment 1, the anthocyanin content of the product is 229mg/100g.

Example 3

1. Material selection and cleaning: Select fresh purple sweet potatoes without rot, mildew, or cracks, use clean water to wash off the sediment on the surface of the purple sweet potatoes, and clean the sediment in the depressions with a brush.

2. Steaming and peeling: After cleaning the purple sweet potatoes, drain all the water and arrange them in a plate. Before steaming, the steamer needs to be preheated. The steaming temperature is 95-120°C, the steaming time is 15-20 minutes, and the steam pressure is 1-20 minutes. 2Mpa. After the purple sweet potato is steamed, cool it at room temperature, cool it to room temperature, and peel it.

3. Chopping and crushing, ingredients: Put the peeled cooked purple sweet potato into a chopping machine and crush it into purple sweet potato puree. During the chopping and mixing process, add xylitol, the addition amount is 100kg of purple sweet potato pulp and 10kg of xylitol.

4. Shaping and freeze-drying: Put the purple sweet potato puree into a mold to shape it, put it into a refrigerator for pre-freezing, and use a freeze dryer to freeze-dry it. The moisture content of the final freeze-dried product is between 3% and 5%.

5. Vacuum-sealed bagging: put the freeze-dried product in a bag, and put it in a vacuum-sealed bag.

6. According to the detection method of clause 6 in embodiment 1, the anthocyanin content of the product is 221mg/100g. .

An embodiment of the present invention has been described in detail above, but the content described is only a preferred embodiment of the present invention, and cannot be considered as limiting the implementation scope of the present invention. All equivalent changes and improvements made according to the application scope of the present invention shall still belong to the scope covered by the patent of the present invention.

Claims (9)

1. be rich in a preparation method for the purple potato leisure food of anthocyanidin, it is characterized in that, described in be rich in the preparation method of the purple potato leisure food of anthocyanidin, comprise the steps:

(1) select materials, clean: choose without rotting, without going mouldy, fissureless new light violet potato, use clear water to be washed by the silt on purple potato surface, the silt brush of pocket scrubs clean;

(2) steamed, peeling: after purple potato cleans up, drop to the greatest extent moisture, arrangement puts into dish, and before steamed, food steamer needs preheating, after purple potato cooks, is cooled to room temperature, is peeled off by purple potato skin;

(3) cut and mix fragmentation, batching: by the ripe purple potato after peeling, put into cutmixer and be broken into purple mashed potatoes, cut in the process of mixing and add sucrose or without acarbose;

(4) moulding, freeze drying: purple mashed potatoes are put into mould moulding, put into refrigerator pre-freeze, uses freeze drier freeze drying;

(5) product that freeze drying is good is positioned in bag, vacuum seal.

2. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1, it is characterized in that, in described step (2), steamed temperature is 95 ~ 120 DEG C, and the steamed time is 15 ~ 20min, and steam pressure is 0 ~ 0.2Mpa.

3. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1, is characterized in that, in described step (3), the interpolation quality of sucrose is the 8-12% of purple potato quality.

4. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1 or 3, it is characterized in that, in described step (3), sucrose is white granulated sugar or soft white sugar.

5. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1, is characterized in that, in described step (3), interpolation be one in stevioside glycosides or xylitol without acarbose.

6. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 4, is characterized in that: the interpolation quality of stevioside glycosides is the 0.06-0.08% of purple potato quality.

7. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 4, is characterized in that: the interpolation quality of xylitol is the 8-12% of purple potato quality.

8. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1, is characterized in that, in described step (4), the moulding shape of mould is the one in disc-shaped or square piece shape, and the thickness of described is 2-5mm.

9. a kind of preparation method being rich in the purple potato leisure food of anthocyanidin according to claim 1, is characterized in that, in described step (4), freeze drying is vacuum freeze drying.