CN103238801B - Preparation method of seasoning burdock crisp chips through microwave-assisted efficient vacuum frying - Google Patents

Abstract

The invention discloses a method for preparing seasoned burdock chips by microwave-assisted high-efficiency vacuum frying, which belongs to the technical field of fruit and vegetable chips processing. The invention takes fresh burdock as raw material, washes burdock, peels and slices it in water, soaks in color-protecting liquid, blanches, dips, slow-freezes, microwave-assisted vacuum frying, vacuum deoiling, seasoning, baking, cooling and packaging, and sterilizes the finished product preservation. Treat with color-protecting agent to maintain the color of the product; use high-efficiency microwave heating to realize puffing at low temperature; use slow freezing to improve product crispness, low-temperature vacuum frying technology can maintain the color and unique flavor of burdock chips , nutrients, low oil content, fried oil is not easy to oxidize, and the product has a long shelf life. The product has high cellulose content, is crispy and delicious, not greasy, convenient and hygienic, and is a snack food suitable for all ages. The invention adopts vacuum frying and microwave combined dehydration, so that the efficiency of vacuum frying is increased by 20%-30%, the types of burdock processed products are enriched, and great economic benefits are expected to be produced.

Description

A method for preparing seasoned burdock chips by microwave-assisted high-efficiency vacuum frying

technical field

A method for preparing seasoned burdock crisps by microwave-assisted high-efficiency vacuum frying relates to a microwave-assisted vacuum frying dehydration processing technology with high thermal efficiency, and belongs to the technical field of fruit and vegetable crisps processing.

Background technique

Burdock, the Latin scientific name is Arctium lappal, and it is also known as beef vegetable, vigorous seed, evil real, burdock seed, bat thorn, Japanese radish, American ginseng, bullwhip and so on. Burdock is a biennial herbaceous plant of Compositae, the wild species is a perennial root plant, and the cultivated species is a biennial or triennial large herbaceous plant. The main producing areas are Xuzhou, Hebei, Xinjiang and other places. The tender leaves and fleshy roots of burdock are edible. It is a health-care vegetable with high nutritional value. It is known as the "King of Vegetables". Its nutritional value can be compared with ginseng. Beloved around the world, the root of burdock is a gentle and nutritious herb that helps keep the body in good working order. Burdock can be eaten every day without any side effects, and has a restorative function on the balance of various systems in the body. The Japanese, the longest-lived nation in the world, eat the root of burdock all the year round.

Nutritional analysis shows that burdock root contains arctiin, protein, alkaloids, vitamins B ₁ , B ₂ , and various amino acids necessary for the human body, especially the high content of amino acids with special pharmacological effects, such as asparagus, which has a brain-building effect. Amino acid accounts for 25%-28% of the total amino acids, and arginine accounts for 18%-20%. Every 100 g of burdock fresh vegetables contains about 87 g of water, 4.1-4.7 g of protein, 3.0-3.5 g of carbohydrates, 0.1 g of fat, 1.3-1.5 g of cellulose, and up to 390 mg of carotene, which is 280 times higher than that of carrots. C 1.9 mg. Among the mineral elements, it contains 240 mg of calcium, 106 mg of phosphorus, 7.6 mg of iron, and other various nutrients. The fleshy root of burdock is tender and crisp, and can be fried, cooked, eaten raw or processed into beverages.

The cellulose content of burdock is high, which can promote the peristalsis of the large intestine, help defecation, reduce the accumulation of toxins and waste in the body, and achieve the effect of preventing stroke, gastric cancer and uterine cancer. Western medicine believes that in addition to its pharmacological effects such as diuresis, eliminating accumulation, eliminating phlegm and stopping diarrhea, it is also used as a dietary therapy for constipation, high blood pressure, and high cholesterol. Studies have shown that burdock has obvious effects of lowering blood sugar, lowering blood fat, lowering blood pressure, tonifying kidney and strengthening yang, laxative, inhibiting the growth and proliferation of cancer cells and removing heavy metals in water. It is an ideal natural health food. In 2002, the National Ministry of Health included burdock in the list of items that can be used as health food.

Microwave-assisted vacuum frying is a combination of vacuum frying and microwave heating. When the pressure is reduced, the partial pressure of water vapor in the gas phase can be reduced, and the boiling point temperature of the material is reduced, so that the material can be processed at a low temperature. Dehydration speeds up the rate of moisture diffusion. As the pressure in the fryer decreases, the boiling point of water decreases, and the evaporation speed of the water on the surface of the material accelerates, which accelerates the migration speed of the internal water; due to the rapid evaporation of the surface water, a large amount of heat is absorbed, so that the temperature of the material surface rapidly This increases the internal and external temperature gradient, accelerates the migration of internal moisture, forms a higher internal steam pressure difference, and releases the gas wrapped inside the material quickly, prompting the rapid expansion of the material and improving the expansion effect. Vacuum frying is used for food processing at lower temperature (80-120 ℃) and higher vacuum degree (0.07-0.098 MPa), because the material is in a low-oxygen environment, this process can reduce or even avoid food processing at high temperature. Oxidation, maintain the color, flavor and nutritional content of the original product, so it is suitable for the processing of snack food. The vacuum system is in a negative pressure state relative to the atmospheric pressure, and its absolute pressure is lower than the atmospheric pressure. Food processing in this relatively hypoxic state can reduce or even avoid the harm caused by oxidation, such as fatty acid spoilage, enzymatic browning or other oxidative deterioration.

High-efficiency microwave heating has outstanding advantages such as fast heat transfer and short heating time. At the same time, the microwave penetrates the inside of the food material and directly acts on the water molecules, causing the inside of the material to be heated instantly, resulting in the rapid vaporization and migration of moisture inside the material, and the formation of numerous microporous channels, resulting in a porous structure, and preventing the product from shrinking. Thereby greatly improving the brittleness of the product. The vacuum environment can reduce the pressure of the microwave drying system, and at the same time use microwave energy to dry and expand the material. Vacuum microwave frying can achieve high-efficiency, uniform, and low-cost dehydration of materials, while retaining the original color, flavor and nutrients of the materials, and the product has low oil content and a crispy taste.

Far-infrared sterilization technology does not require media, and the heat penetrates directly from the surface of the object to the inside, so it can not only be used for sterilization of general powder and block foods, but also for sterilization and sterilization of nut foods such as coffee beans, peanuts and grains. Deactivation of enzymes and sterilization of bagged food.

The quality requirements of export burdock products are very high, but in the actual production process, the problem of burdock peeling and discoloration often occurs. Therefore, Li Jiansong analyzed and explored the mechanism and control method of peeled burdock discoloration during processing, and solved the problem of burdock discoloration. The results show that the color protection effect of using 1% citric acid and 2% saline solution is good, and the product quality is very good.

Weng Jun et al. disclosed a production process of freeze-dried burdock (patent number: 201010234436.9), using fresh burdock as raw material, cleaning and slicing it and then sterilizing it, then putting it into a freezing tray for precooling for 12-24 hours before freezing it , and then vacuum-dry the frozen sliced burdock: the vacuum degree of the sublimation drying stage is 80-120 Pa, and the vacuum degree of the analytical drying stage is 1-10 Pa. After the drying is completed, the freeze-dried burdock is obtained. This process fully retains the food tissue structure, nutrients and flavor substances of burdock, and the product has good rehydration and light weight. But this product is not as full of local flavor as deep-fried product, can not produce a kind of special fragrance.

Ding Zhien and others disclosed a method for protecting and preserving the color of burdock (patent number: 201110104778.3). After blanching, it is soaked in a color-protecting solution. CaCl ₂ aqueous solution, 0.2%-0.5% citric acid aqueous solution, 0.2%-0.5% VC aqueous solution are mixed in equal volumes.

Huang Xuesong and others studied the effect of some treatment methods on the discoloration of burdock slices. The results showed that 40 mg/kg of ascorbic acid solution or hot blanching above 90 ℃ for 10 minutes could prevent the discoloration of burdock slices. Vacuuming for 30 min at a vacuum of 0.093 MPa can prevent the cambium of the burdock slices from turning yellow after blanching.

Xu Fei and others studied the processing technology of crispy burdock strips, and developed crispy burdock strips with excellent aroma, taste and shape by using high-pressure softening, freezing, vacuum frying, sugar coating and baking lamp technology.

Han Qinghua et al. compared the energy consumption and quality analysis of hot air drying and microwave vacuum drying puffed apple slices. The results showed that the drying capacity of microwave vacuum drying puffed was 48.46% higher than that of hot air drying, and the unit energy consumption was saved by 32.32%. Nutrients are good.

Song Xianju, Zhang Min and others adopted vacuum microwave-vacuum frying-vacuum microwave three-stage dehydration process, and optimized the three-stage joint dehydration process, and obtained the best turning point of the three-stage joint dehydration process, so as to obtain satisfactory low-fat content of potato chips.

In the master's degree thesis of Hunan Agricultural University "Research on the Process of Reducing the Oil Content of Potato Chips Using Microwave Frying Technology", in order to make the microwave-processed potato chips have the flavor of fried food, a certain amount of oil is sprayed on the surface of the potato chips before baking. , In the process of microwave treatment, a "fried" environment can be produced, and the oil content of the finished product can be reduced by controlling the amount of oil applied, so as to solve the problem of aging of fried potato chips with low-fat compound oil pressing. Although this method can solve the problem of high oil content, the process of oiling and wrapping potato slices before microwave baking is manually stirred and mixed, which will increase the work intensity in actual production and is not conducive to improving Productivity.

Isil Barutcu (2009) studied microwave frying and the influence of different types of flour on the microstructure of paste coating film. The frying equipment used was microwave oven equipment. This method is not suitable for industrial production, and the fat content of normal pressure fried products High, often not liked by consumers, and a large number of nutrients in the product are lost in large quantities.

M.O.Ngadi et al. (2009) studied the effect of microwave treatment on deep-fried chicken nuggets, and the results showed that microwave pretreatment can significantly affect the water loss rate and oil intake of the product.

Zhang Min, Sun Jincai, etc. disclosed a method for producing fruit and vegetable chips combined with atmospheric heat drying and vacuum frying (patent number: 200310112745.9). After conventional selection, washing, peeling (core), slicing, blanching and enzyme inactivation, etc., the raw materials are first subjected to normal pressure heat drying, frying and dehydration, centrifugal deoiling, seasoning and packaging. This invention patent adopts a new process of pre-atmospheric heat drying and vacuum frying combined dehydration, which increases the pre-dehydration, so that the product has the characteristics of low oil content, short frying time and good initial shape. The disadvantage of this patent is that the pre-drying process takes a long time and the production efficiency is slightly low.

Hou Yonghong disclosed a processing method of fruit and vegetable crisps rich in organic selenium and low oil content (patent number: 200910183029.7). This patent selects fruits and vegetables with a total selenium content of 0.5-1.0 mg/kg, and uses vacuum microwave drying before vacuum low-temperature frying. The vacuum microwave drying temperature is controlled at 70-75 ℃, the time is 4-6 minutes, and the vacuum degree is 104-103 Pa. Adopting this patent can reduce the oil content of the product and increase the storage period. Due to the increased health effect of rich organic selenium, it is suitable range of consumers.

Zhang Min, Cai Jinlong and others disclosed a low-salt-content seawater vegetable vacuum frying processing method (Patent No.: 200710134748.0), which uses a new process of desalination by freezing and vacuum infiltration at the same time, reducing the salt content in raw materials Quantity, and the method of pre-freezing improves the puffing degree of the product. The main process of making fruit and vegetable chips is: cleaning and selecting seawater vegetable raw materials, blanching, desalting, freezing, vacuum frying, deoiling, seasoning, cooling and packaging, and preservation of finished products. This patented product has low fat content, short frying time and less color change. But the vacuum penetration time is longer.

Zhang Min, Zhu Yinyin, etc. disclosed a joint processing method for processing crunchy peas by using dried peas (patent number: 201110413451.4). Dry peas were used as raw materials, and after the peas were cleaned, soaked and selected, they were blanched, color-protected, dipped, and drained. , freezing, negative pressure microwave spray drying, vacuum frying, vacuum deoiling, seasoning, cooling packaging, and product preservation. This invention uses negative pressure microwave spray drying to realize drying before low-temperature frying, so that the product has better crispness and lower oil content.

Tianjin Zhongying Nano Technology Development Co., Ltd. discloses a production method of fruit and vegetable puffed crisps (patent number: 200610016370.X), providing a production method of fruit and vegetable puffed crisps with fruits and vegetables as raw materials, which is characterized in that the production steps 1) Select fresh fruits or vegetables; 2) Wash the fruits or vegetables, inactivate enzymes, slice and dry them, put them into a low-temperature vacuum fryer, and heat up to 85-90°C; 3) Puff; 4) Puff the puffed The final material is cooled to room temperature, packed into bags, and stored in a vacuum. This patent retains the nutritional ingredients of fruits and vegetables, and is convenient to eat and has high nutritional value. The weak point of this invention is exactly that without vacuum deoiling, the product has a higher fat content.

At present, the processing of burdock in the market is limited to freeze-drying or making pickles, etc. Most researchers at home and abroad pay more attention to the research of functional components in burdock, but seldom study the processing technology of burdock. At present, there are many vacuum-fried fruit and vegetable crisps on the market, but there are basically no seasoning products that utilize microwave-assisted high-efficiency vacuum frying. Therefore, the present invention can achieve high-efficiency, uniform, and low-cost dehydration of materials, and the product has low fat content, crisp taste, special fragrance, and is convenient to carry.

Contents of the invention

The purpose of the present invention is to provide a microwave-assisted high-efficiency vacuum frying method for preparing seasoned burdock chips, which relates to the processing of dehydrated fruits and vegetables and vacuum microwave fried food, and expands the types of burdock snack food.

Technical scheme of the present invention:

A method for preparing seasoned burdock chips by microwave-assisted high-efficiency vacuum frying. Fresh burdock is used as a raw material. After the burdock is washed, peeled in water, sliced, soaked in a color-protecting solution, scalded to kill enzymes, and soaked for a period of time After draining, slow freezing, microwave-assisted vacuum frying, vacuum deoiling, seasoning, baking, cooling and packaging, the finished product is sterilized and preserved. Specific steps are as follows:

(1) Raw material pretreatment: clean the burdock, put it in water, peel and slice;

(2) Soaking in color-protecting solution: put the cut burdock slices in 95°C color-protecting solution (mass concentration: 0.5% ascorbic acid + 0.5% NaCl), soak at room temperature for 30 minutes;

(3) Burning to kill enzymes: put the burdock slices after color protection into 0.5% D-isoVC sodium solution at 95°C for 3-5 minutes to kill enzymes, take them out immediately and cool them with cooling water;

(4) Impregnation: Put the blanched burdock slices into the soaking solution (mass concentration: 5% glucose + 20% maltodextrin) for 3 hours, take it out, wash the soaking solution on the surface of the burdock slices, and drain the surface moisture;

(5) Slow freezing: Slowly freeze the drained burdock slices at -20°C for 12 hours;

(6) Microwave-assisted vacuum frying: Turn on the microwave source of the microwave-assisted vacuum frying equipment, control the microwave power to 2000 W, so that the oil temperature rises to about 95±2°C in a short period of time, and the vacuum degree of frying is 0.095 MPa, immerse the inner filter basket loaded with burdock slices into palm oil and start frying. The frying time is related to the amount of raw materials. The general frying time is 15-25 minutes. The end of frying can be observed by the observation mirror of the fryer Judgment, when there are no more air bubbles in the fat, it is the end of frying;

(7) Vacuum deoiling: After frying, turn on the oil pulse jet pump, pump the palm oil back to the oil tank, turn on the centrifugal deoiling and stirring motor, and carry out centrifugal deoiling under vacuum conditions. The time is 5-8 minutes. After the deoiling is completed, open the atmospheric switch valve to restore the atmospheric pressure, then open the movable vacuum hatch cover, and take out the fried products;

(8) Seasoning: Add 2%-2.5% sugar, 1%-1.5% edible salt, 0.01% I+G, 0.2% monosodium glutamate and 2%-3% soy sauce powder or 4%-6% by weight of fried burdock slices % cream powder, mix well to get soy sauce-flavored or creamy burdock slices;

(9) Baking: Put the seasoned burdock slices in an oven at 110°C and bake for 30-45 minutes to make the product thick and even in flavor;

(10) Cooling and packaging: After baking, cool to room temperature, then pack, and use high-density polyethylene bags for nitrogen-filled packaging;

(11) Sterilization and preservation: After packaging, far-infrared sterilization is used, and the wavelength is selected to be 6.0 μm. After sterilization for 0.5-1.0 min, it is stored in the dark at room temperature, which is the seasoned burdock crisp product.

Beneficial effects of the present invention:

Compared with the traditional room temperature frying method, the microwave-assisted high-efficiency vacuum frying method can not only realize the frying of burdock in a low-oxygen state, but also use vacuum deoiling to avoid the oil content caused by room temperature frying. High, the product color is yellow, easy to burn and other disadvantages. Using a microwave source as a heating source, on the one hand, it can achieve instantaneous heating, the output power of the microwave can be adjusted at any time, and the oil temperature can be changed without inertness. There is no "waste heat" phenomenon, which is very conducive to automatic control and continuous production. Need; on the other hand, the microwave penetrates the inside of the burdock and directly acts on the water molecules, causing the inside of the burdock to be heated instantly, resulting in the rapid vaporization and migration of the internal water, and the formation of numerous microporous channels, resulting in a porous structure, and preventing the shrinkage of the product , thus greatly improving the brittleness of the product. Therefore, vacuum microwave frying is used, the processing time is short, the frying temperature is low, and the original nutritional content of burdock is greatly preserved. It has good color, aroma and taste, good crispness, low fat content, and long shelf life. The processing of burdock provides a method to solve the problem of poor storage resistance of fresh burdock, enrich the types of burdock products, and is expected to generate greater economic benefits.

Detailed ways

Embodiment 1: Production and processing method of microwave-assisted vacuum frying conditioning burdock slices (soy sauce flavor)

After cleaning the burdock, put it in water, peel and slice it, then soak it in the color protection solution (0.5 % ascorbic acid + 0.5 % NaCl) at room temperature for 30 minutes, put the burdock slices in 0.5% D-isocyanate at 95 °C after color protection. Blanch in VC sodium solution for 3-5 minutes, take it out immediately and cool with cooling water. Then put it in the soaking solution (5% glucose + 20% maltodextrin) for 3 hours, take it out, wash the soaking solution on the surface of the burdock slices, drain the water on the surface, and slow freeze at -20°C for 12 hours. Vacuum microwave fry the frozen burdock slices, turn on the microwave source of the vacuum microwave frying equipment, and control the microwave power to 2000 W, so that the oil temperature rises to about 95±2°C in a short period of time, and the vacuum The temperature is 0.095 MPa. Immerse the inner filter basket loaded with burdock slices into palm oil and start frying. The frying time is related to the amount of raw materials. The general frying time is 15-25 minutes. The frying end point can be determined by observing the frying machine Judging by the observation mirror, when there are no more air bubbles in the fat, it is the end of frying. After frying, turn on the oil pulse jet pump, pump the palm oil back into the oil tank, turn on the centrifugal deoiling and stirring motor, and carry out centrifugal deoiling under vacuum conditions. Adjust the speed to 300 r/min, and the centrifugal time to 5-8 minutes. After deoiling, open the atmospheric switch valve to restore the atmospheric pressure, then open the movable vacuum hatch to take out the fried products. Seasoning (based on the weight of fried burdock slices: add 2%-2.5% sugar, 1%-1.5% edible salt, 0.01% I+G, 0.2% monosodium glutamate and 2%-3% soy sauce powder, mix well, and get Soy sauce-flavored burdock slices), baked in an oven at 110°C for 30-45 minutes, filled with nitrogen (99.99% purity) after cooling, packed in high-density polyethylene bags of various specifications as needed, and stored by far-infrared sterilization.

Example 2: Production and processing method of microwave-assisted vacuum frying conditioning burdock slices (butter flavor)

After cleaning the burdock, put it in water, peel and slice it, then put it in the color protection solution (0.5 % ascorbic acid + 0.5 % NaCl), soak it at room temperature for 30 minutes, put the burdock slices in 0.5% D at 95 ℃ after color protection - Blanch in iso-VC sodium solution for 3-5 minutes, take it out immediately and cool with cooling water. Then put it in the soaking solution (5% glucose + 20% maltodextrin) for 3 hours, take it out, wash the soaking solution on the surface of the burdock slices, drain the water on the surface, and slow freeze at -20°C for 12 hours. Vacuum microwave fry the frozen burdock slices, turn on the microwave source of the vacuum microwave frying equipment, and control the microwave power to 2000 W, so that the oil temperature rises to about 95±2°C in a short period of time, and the vacuum The temperature is 0.095 MPa. Immerse the inner filter basket loaded with burdock slices into palm oil and start frying. The frying time is related to the amount of raw materials. The general frying time is 15-25 minutes. The frying end point can be determined by observing the frying machine Judging by the observation mirror, when there are no more air bubbles in the fat, it is the end of frying. After frying, turn on the oil pulse jet pump, pump the palm oil back into the oil tank, turn on the centrifugal deoiling and stirring motor, and carry out centrifugal deoiling under vacuum conditions. Adjust the speed to 300 r/min, and the centrifugal time to 5-8 minutes. After deoiling, open the atmospheric switch valve to restore the atmospheric pressure, then open the movable vacuum hatch to take out the fried products. Seasoning (Based on the weight of fried burdock slices: add 2%-2.5% sugar, 1%-1.5% edible salt, 0.01% I+G, 0.2% monosodium glutamate and 4%-6% butter powder, mix well, and get Buttery burdock slices), baked in an oven at 110°C for 30-45 minutes, filled with nitrogen (99.99% purity) after cooling, packed in high-density polyethylene bags of various specifications according to needs, and stored by far-infrared sterilization.

Claims (1)

1. the auxiliary fried method of preparing seasoning burdock crisps of high-efficiency vacuum of microwave, is characterized in that taking fresh burdock as raw material, by peeling after burdock cleaning, in water, section, adopt colour protecting liquid to soak and protect look, the blanching enzyme that goes out, drained after dipping a period of time, slow freezing, microwave assisted vacuum is fried, vacuum de-oiling, seasoning, baking, cooling packing, finished product sterilization and preservation; Step is as follows:

(1) pretreatment of raw material: be placed on peeling in water, section after burdock is cleaned up;

(2) colour protecting liquid soaks: the burdock sheet after cutting is put into the colour protecting liquid of mass concentration 0.5 % ascorbic acid and 0.5 % NaCl, soak at room temperature 30 min;

(3) the blanching enzyme that goes out: by the D-sodium iso-vc solution blanching 3-5 min that protects burdock sheet after look and put into the mass concentration 0.5% of the 95 DEG C enzyme that goes out, after taking out immediately by water quench;

(4) dipping: the maceration extract of the burdock sheet after blanching being put into mass concentration 5% glucose and 20% maltodextrin floods 3 h, cleans the maceration extract on burdock sheet surface after taking out, and drains its surperficial moisture;

(5) slow freezing: the burdock sheet after draining is placed on to slow 12 h that freeze at-20 DEG C;

(6) microwave assisted vacuum is fried: the microwave source of opening microwave assisted vacuum frying apparatus, controlling microwave power is 2000 W, make oil temperature rise in a short period of time 95 ± 2 DEG C, fried vacuum is 0.095 MPa, fried the interior beginning of interior filter basket immersion palm oil that packs burdock sheet into, the fried time is definite according to material quantity, and the fried time is 15-25 min, fried terminal judges by the peephole of observing Fryer, is fried terminal when no longer including in grease when bubble outwards overflows;

(7) vacuum de-oiling: open the spouted pump of oily pulse after fried end, palm oil is drawn back to oil groove, open centrifugation de-oiling and stirring motor, under vacuum condition, carrying out centrifugation de-oiling adjusting rotary speed is 300 r/min, centrifugation time is 5-8 min, and de-oiling finishes rear unlatching atmosphere controlled valve, recovers atmospheric pressure, then open movable vacuum hatchcover, take out fried product;

(8) seasoning: add fried rear burdock sheet weighing scale 2%-2.5 % white sugar, 1%-1.5 % edible salt, 0.01% I+G, 0.2% monosodium glutamate, 2%-3% powdered soy or 4%-6% dry cream, mix thoroughly, obtain the burdock sheet of soy sauce taste or creamy taste;

(9) baking: burdock sheet good seasoning is put into 110 DEG C of oven for baking 30-45 min, make the local flavor of product thick and heavy and even;

(10) cooling, packaging: be cooled to room temperature after baking, then pack, adopt high density polyethylene (HDPE) bag to carry out nitrogen-filled packaging;

(11) sterilization and preservation: adopt far infrared sterilization after packaging, selecting wavelength is 6.0 μ m, and after sterilization 0.5-1.0 min, lucifuge preservation under normal temperature, is seasoning burdock crisps product.