CN106578035A - Physical fresh-keeping method for broad beans - Google Patents

Abstract

The invention discloses a physical fresh-keeping method for broad beans and solves the problems of insect attack, low nutritional value and the like on broad beans during storage in the prior art. In the technical scheme, the method includes the steps of: soaking and cleaning fresh broad beans, draining the broad beans, performing high-pressure permeation treatment and vacuum high-voltage electric field corona discharge treatment, and vacuum-packaging and refrigerating the broad beans. In the invention, volatilized artemisia argyi gas shows an approximate supercritical status under a high pressure, wherein the gas has very strong permeation capability and can permeate in the interior of the broad beans, thereby achieving effective antibacterial and insecticidal function. Through the vacuum high-voltage electric field corona discharge treatment, the molecular structure of volatile components in the artemisia argyi is damaged, thereby further removing odors. Through the treatment, fresh-keeping period of the broad beans is greatly prolonged, and the broad beans have excellent color, smell and taste.

Description

A kind of physical fresh-keeping method of broad bean

technical field

The invention belongs to the field of food preservation, and in particular relates to a physical preservation method of broad beans.

Background technique

Broad bean (Vetacea), also known as Luohan bean, Hudou bean, South bean, vertical bean, Buddha bean, Fabaceae, and Vetacea are annual herbs. Tender broad beans can benefit Qi and strengthen the spleen, dampness and swelling. In addition, it is rich in nutrients. Every 100 grams of broad beans contains 9 grams of protein and 19 grams of carbohydrates. It is also rich in dietary fiber, calcium, phosphorus, potassium, vitamin B, carotene and other healthy nutrients. The protein in tender broad beans is second only to soybeans in various beans. It also contains phospholipids, an important component of brain and nervous tissue, and rich in choline, which can enhance memory and strengthen the brain. In addition, broad beans are low-calorie foods, which are high-quality green foods for patients with hyperlipidemia, hypertension and cardiovascular diseases. Modern people also believe that broad beans are also one of the anti-cancer foods, which can prevent intestinal cancer.

Nowadays, according to the nutritional characteristics of broad beans, relevant researchers have developed a variety of fresh-keeping methods for broad beans, for example: Chinese patent application number CN201510671383. Fresh-keeping method of broad beans", etc. The content of the research is to use the method of soaking with chemical substances to keep fresh. However, chemical substance immersion treatment inevitably has food safety hazards.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned technical problems and provide a physical fresh-keeping method for broad beans with simple and reliable process, long-term freshness, color retention, good taste, no chemical reagent residue, and high nutritional value.

The physical fresh-keeping method of broad beans of the present invention is as follows: firstly, high-pressure infiltration treatment is performed on fresh broad beans with mugwort essential oil gas in an approximate supercritical state; then, high-voltage electric field corona discharge treatment is applied to broad beans;

Specifically include the following steps:

(1) Soaking and cleaning: immerse fresh broad beans in ultra-pure water to remove impurities and dust on the surface of broad beans, and then sonicate for 1 to 1.5 hours;

(2), draining: the broad beans after ultrasonic treatment are drained quickly under dark and low temperature conditions, and then packed into a high-pressure air chamber;

(3) High-pressure osmosis treatment: Add mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100-120°C, and use a high-pressure pump to pump the volatilized mugwort essential oil gas into the high-pressure gas chamber containing broad beans. In the chamber, pressurize the high-pressure air chamber and keep it at 9-14MPa, so that the gas density of mugwort essential oil reaches an approximate supercritical state of 0.68-0.85g/ ^cm3 , and the treatment time is 50-80min;

(4), vacuum high-voltage electric field corona discharge treatment: the broad beans after high-voltage infiltration treatment are packed into a high-voltage electric field corona discharge device, and high-voltage electric field corona discharge treatment is carried out in a vacuum state;

(5) Vacuum-pack the faba beans treated by corona discharge in an empty high-voltage electric field, put in a deoxidizer, and keep fresh in refrigeration at 1-5°C.

In the step (2), after the draining, carry out air blowing and mixing treatment, and dry for 30 to 50 minutes with a mesh belt air dryer at 40 to 60°C;

In the step (2), when draining, the low temperature is controlled to be 15-25°C.

In the step (4), the intensity of the high-voltage corona field is controlled to be 50-210KV, and the treatment time is 12-18h.

In step (4), the degree of vacuum is controlled at 2000-2500Pa.

The high-voltage electric field corona discharge device at least includes a metal plate and a discharge needle, the maximum tile thickness of the broad beans on the metal plate is 10-20 mm, the minimum distance between the discharge needle and the metal plate is 40-60 mm, and the distance between the discharge needles The spacing is 50-65mm.

Aiming at the problems existing in the background technology, the inventor conducted in-depth research on the physical fresh-keeping method of broad beans, and selected mugwort among many natural insecticidal plants, and used the volatilization of mugwort essential oil to exert antibacterial and insecticidal effects, but the inventor It was also found that since the broad bean has a thicker skin, it is difficult to make the mugwort essential oil penetrate into the broad bean only by ordinary methods such as fumigation or soaking. In order to solve the above problems, the inventor first uses a constant temperature environment to promote the volatilization of mugwort essential oil, and then makes the volatilized mugwort gas appear in an approximate supercritical state under high pressure conditions, so that it has a strong penetrating ability, so that it can penetrate Into the interior of broad beans to obtain excellent antibacterial and insecticidal effects.

The mugwort is highly volatile, because the pungent taste remains on the broad beans, which affects the mouthfeel and fragrance of the broad beans. For this problem, the inventor carried out a vacuum high-voltage electric field corona discharge treatment on the broad beans, and utilized the corona discharge process to The ion beam generated in the air increases the energy of the mugwort gas molecules remaining in the broad bean, causing the breakage of the hydrogen bonds between the chain molecular groups, thereby breaking the molecular structure of the volatile components in the mugwort, and quickly and effectively eliminating the mugwort. At the same time, the inventor also found that the vacuum high-voltage electric field corona discharge treatment also has a killing effect on the worm eggs in the broad bean. In the vacuum environment, on the one hand, it can strengthen the effect of the high-voltage corona field, and it can further remove odors, and completely solve various problems caused by using mugwort essential oil.

The selected temperature to promote the volatilization of mugwort essential oil is preferably 100-120°C, and the temperature selection should not be too high to avoid adverse chemical reactions of mugwort essential oil due to high temperature; High pressure capacity puts forward higher requirements, and will increase the loss of nutrients in broad bean products during high-pressure osmosis treatment. If it is too low, the gas density of mugwort essential oil cannot reach the approximate supercritical state of 0.68-0.85g/cm ³ ; the selected The high-pressure permeation time is 50-80 minutes, and the high-pressure permeation time should not be too long, but it must be fully in contact with the supercritical mugwort gas with strong penetrative power, penetrate deep into the broad bean, and ensure the insecticidal and antibacterial effects.

Further, preferably after step (2) is drained, it is then processed by air blowing and mixing to reduce the moisture content on the surface of broad beans, and further inhibit the growth of microorganisms on the surface of broad beans. Drying under the condition of 30-50 minutes, if the temperature is too high, it will not only cause the destruction of heat-sensitive nutrients, but also choose a higher temperature on the surface of broad beans to meet the needs of external water evaporation, and the internal water will migrate to the surface at a faster rate, which will easily lead to the soluble Components are precipitated on the surface, thereby causing the hardening of the broad bean surface; the selected time should not be too short, because too short time is not conducive to the drying of the broad bean surface, and it is preferable to control the water content of the broad bean to below 10%.

In step (4), the high-voltage electric field corona discharge device is a commercially available product (such as produced by Shanghai Zhizhao Environmental Protection Technology Co., Ltd.), which at least includes a metal plate and a vertically downward discharge needle above the metal plate. The maximum tiling thickness on the plate is preferably 10-20mm, the distance between the discharge needles is 50-65mm, and the minimum distance between the tip of the discharge needle and the metal plate is preferably 40-60mm. The selected maximum tiling thickness and the distance between the tip of the discharge needle and the metal plate should not be too large. Too large a distance will not be effective in killing insect eggs, and it will also prolong the time of high-voltage electric field corona discharge treatment; The piezoelectric corona field intensity is 50-210KV. If the high-voltage electric field corona discharge intensity is too high, higher requirements will be put forward for the production conditions, and it will also have an adverse effect on the quality of broad beans. However, if the high-voltage corona field intensity is below 50KV, it will kill The effect of killing insect eggs is not significant; too long time selection is not conducive to controlling production efficiency, and long-term high-voltage electric field corona discharge treatment is not conducive to maintaining the quality of broad beans, and too short time will affect the effect of killing insect eggs;

Beneficial effect:

(1) No chemical substances are used for soaking treatment in the whole process, which avoids the food safety hazards caused by chemical substances. (2) In the high-pressure infiltration process, making mugwort essential oil behave in an approximate supercritical state can play a more significant antibacterial and insecticidal effect than simply using mugwort essential oil for fumigation. (3) Using the ion beam generated in the corona discharge process to destroy the molecular structure of the volatile components in Artemisia argyi, and also have a significant killing effect on the insect eggs in the broad bean. In the process of corona discharge, the temperature of the material will not be raised, and combined with the vacuum environment, it also solves the problem of the odor of the final product caused by the residual mugwort gas. (4) The broad beans prepared by the method of the present invention can be refrigerated and kept fresh for more than 80 days at 1-5° C., and their color, taste, smell and nutritional value are effectively guaranteed, and have broad market application prospects.

detailed description

The technical solutions in the present invention will be clearly and completely described below in conjunction with specific embodiments.

Example 1

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the above-mentioned broad beans picked in ultrapure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 1.5 hours;

(3), draining, air-flow blowing and mixing treatment: quickly drain the broad beans after super-treatment at a low temperature of 15°C in the dark, and then dry them for 30 minutes at 40°C with a mesh-belt airflow dryer;

(4) High-pressure osmosis treatment: add 10ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g red dates , and pressurize the high-pressure chamber to ensure that the pressure in the high-pressure chamber is 9MPa. At this time, the mugwort essential oil gas shows an approximate supercritical state with a density of 0.68-0.85g/cm ³ , and the processing time is 50min;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the thickness of the tile after loading is 10mm, and the distance between the tip of the discharge needle and the metal plate is 40mm, and the high-voltage corona The field strength is 50KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 12 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1°C.

Example 2

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the above-mentioned broad beans picked in ultrapure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 2 hours;

(3), draining, air blowing and mixing treatment: quickly drain the treated broad beans in the dark at a low temperature of 25°C, and then dry them for 50min at 60°C with a mesh belt type airflow dryer;

(4) High-pressure osmosis treatment: add 15ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g red dates , and pressurize the high-pressure chamber to ensure that the pressure in the high-pressure chamber is 14MPa. At this time, the mugwort essential oil gas is in an approximate supercritical state with a density of 0.68-0.85g/cm ³ , and the processing time is 80min;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the tile thickness after loading is 20mm, and the distance between the tip of the discharge needle and the metal plate is 60mm. The field strength is 210KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 18 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a small bag packed with Fe powder deoxidizer by 0.5～1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1-5°C.

Example 3

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the broad beans picked above in ultrapure water to remove impurities and dust on the surface of the broad beans, and then ultrasonically for 1.8h;

(3), draining, air blowing and mixing treatment: quickly drain the treated broad beans in the dark at a low temperature of 20°C, and then dry them for 40min at 50°C with a mesh belt type airflow dryer;

(4) High-pressure osmosis treatment: add 13ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 110°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g red dates , and pressurize the high-pressure air chamber to ensure that the pressure in the high-pressure air chamber is at 12MPa. At this time, the mugwort essential oil gas shows an approximate supercritical state with a density of 0.68-0.85g/cm ³ , and the processing time is 65min;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the tile thickness after loading is 15mm, and the distance between the tip of the discharge needle and the metal plate is 50mm. The field strength is 130KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 15 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1°C.

Comparative Example 1: Artemisia essential oil is not added to high-pressure osmosis

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: keep the outer shell of the above-mentioned broad beans, immerse them in ultra-pure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 1.5 hours;

(3), draining, air blowing and mixing treatment: quickly drain the treated broad beans in the dark at a low temperature of 15°C, and then dry them for 30min at 40°C with a mesh belt type airflow dryer;

(4), high-pressure infiltration treatment: 100g red dates are packed in the high-pressure air chamber, and the high-pressure air chamber is pressurized to ensure that the pressure in the high-pressure air chamber is at 9MPa, and the treatment time is 50min;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the maximum tile thickness after loading is 10mm, the distance between the tip of the discharge needle and the metal plate is 40mm, and the high-voltage electric field The halo field intensity is 50KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 12 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1°C.

Comparative Example 2: Corona discharge treatment without vacuum high voltage electric field

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the above-mentioned broad beans picked in ultrapure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 1.5 hours;

(3), draining, air blowing and mixing treatment: quickly drain the treated broad beans in the dark at a low temperature of 15°C, and then dry them for 30min at 40°C with a mesh belt type airflow dryer;

(4) High-pressure osmosis treatment: add 10ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g broad beans , and pressurize the high-pressure chamber to ensure that the pressure in the high-pressure chamber is 9MPa. At this time, the mugwort essential oil gas shows an approximate supercritical state with a density of 0.68-0.85g/cm ³ , and the processing time is 50min;

(5), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(6) Refrigeration: Refrigerate and keep fresh at 1°C.

Comparative example 3: Using mugwort essential oil without high pressure osmotic treatment

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the above-mentioned broad beans picked in ultrapure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 1.5 hours;

(3), draining, air-flow blowing and mixing treatment: quickly drain the broad beans after super-treatment at a low temperature of 15°C in the dark, and then dry them for 30 minutes at 40°C with a mesh-belt airflow dryer;

(4) Osmosis treatment: add 10ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g broad beans , the high-pressure chamber is not pressurized at this time, and the processing time is 50 minutes;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the thickness of the tile after loading is 10mm, and the distance between the tip of the discharge needle and the metal plate is 40mm, and the high-voltage corona The field strength is 50KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 12 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1°C.

Comparative Example 4: Processing without air blowing

(1), picking: picking fresh broad beans, selecting broad beans without mildew, insect damage, and no mechanical damage;

(2), soaking and cleaning: immerse the above-mentioned broad beans picked in ultrapure water, remove impurities and dust on the surface of the broad beans, and then sonicate for 1.5 hours;

(3), draining: Drain the processed broad beans quickly in the dark at a low temperature of 15°C;

(4) High-pressure osmosis treatment: add 10ml mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100°C, and use a high-pressure pump to pump the volatilized mugwort gas into the high-pressure air chamber containing 100g red dates , and pressurize the high-pressure chamber to ensure that the pressure in the high-pressure chamber is 9MPa. At this time, the mugwort essential oil gas shows an approximate supercritical state with a density of 0.68-0.85g/cm ³ , and the processing time is 50min;

(5) Vacuum high-voltage electric field corona discharge treatment: put broad beans on the metal plate of the high-voltage electric field corona discharge device, ensure that the maximum tile thickness after loading is 10mm, the distance between the tip of the discharge needle and the metal plate is 40mm, and the high-voltage electric field The halo field intensity is 50KV, and the high-voltage electric field corona discharge treatment is carried out in a vacuum state for 12 hours to ensure that the vacuum degree is 2000-2500Pa;

(6), vacuum packaging: the broad beans after drying are vacuum-packed with aluminum foil bags, and put a pouch that is packed with Fe powder deoxidizer by 1% (w/w) in the package;

(7) Refrigeration: Refrigerate and keep fresh at 1°C.

After the broad beans prepared in Examples 1-3 and Comparative Examples 1-4 were stored at 1°C for 30 days, 3 samples were randomly selected from each example to remove the aluminum foil packaging, and the content of malondialdehyde and polyphenol oxidase in the 3 samples were measured by sampling. Activity, soluble sugar, repellent rate, and shelf life.

Table 1 Experimental results of relevant indicators in each case

Claims (7)

1. A physical fresh-keeping method for broad beans, characterized in that, first use the mugwort essential oil gas in an approximate supercritical state to carry out high-pressure infiltration treatment on fresh broad beans, then use high-voltage electric field corona discharge treatment on broad beans, and finally after vacuum packaging refrigeration. 2. the physical fresh-keeping method of broad bean as claimed in claim 1, is characterized in that, comprises the following steps: (1) Soaking and cleaning: immerse fresh broad beans in ultra-pure water to remove impurities and dust on the surface of broad beans, and then sonicate for 1 to 1.5 hours; (2), draining: the broad beans after ultrasonic treatment are drained quickly under dark and low temperature conditions, and then packed into a high-pressure air chamber; (3) High-pressure osmosis treatment: Add mugwort essential oil into the heating chamber, promote the volatilization of mugwort essential oil at a constant temperature of 100-120°C, and use a high-pressure pump to pump the volatilized mugwort essential oil gas into the high-pressure gas chamber containing broad beans. In the chamber, pressurize the high-pressure air chamber and keep it at 9-14MPa, so that the gas density of mugwort essential oil reaches an approximate supercritical state of 0.68-0.85g/ ^cm3 , and the treatment time is 50-80min; (4), vacuum high-voltage electric field corona discharge treatment: the broad beans after high-voltage infiltration treatment are packed into a high-voltage electric field corona discharge device, and high-voltage electric field corona discharge treatment is carried out in a vacuum state; (5) Vacuum-pack the faba beans treated by corona discharge in an empty high-voltage electric field, put in a deoxidizer, and keep fresh in refrigeration at 1-5°C. 3. The physical fresh-keeping method of broad beans as claimed in claim 2, characterized in that, in said step (2), after said draining, carry out air-flow blowing and mixing treatment, use mesh belt type air-flow dryer at 40～60 ℃ Conditions, dry 30 ~ 50min. 4. The physical fresh-keeping method for broad beans as claimed in claim 2 or 3, characterized in that, in the step (2), when draining, the low temperature is controlled to be 15-25°C. The physical fresh-keeping method of broad beans according to claim 2, characterized in that, in the step (4), the intensity of the high-voltage corona field is controlled to be 50-210KV, and the treatment time is 12-18h. The physical fresh-keeping method for broad beans as claimed in claim 2 or 5, characterized in that, in step (4), the degree of vacuum is controlled at 2000-2500Pa. 7. the physical fresh-keeping method of broad bean as claimed in claim 2 or 5 is characterized in that, in described step (4), described high voltage electric field corona discharge device comprises metal plate and discharge needle at least, and described broad bean is placed on metal The maximum tile thickness on the board is 10-20mm, the minimum distance between the discharge needles and the metal plate is 40-60mm, and the distance between the discharge needles is 50-65mm.