Analysis of canning of the hottest edible fungi II

Canned storage analysis of edible fungi (III)

(III) general process of canned storage of edible fungi

according to the different chemical composition of various edible fungi, the canned processing technology is different, but the process is basically the same:

acceptance of raw mushrooms → rinsing → pre cooking → grading → canning → soup → pre sealing → exhaust sealing → sterilization and cooling → wiping → inspection → packaging

the theoretical basis, operation process and equipment of each process are introduced below

1. Acceptance of raw mushrooms: fresh mushrooms are easy to change color and open umbrellas after harvest, so the fresh mushrooms should be treated as quickly as possible from harvest to canning, so as to reduce the exposure time in the air. Contact the place of origin in advance, and conduct acceptance in time after harvest

in order to ensure the quality of cans, the acceptance should be strictly carried out according to the requirements of the specifications of cans. The acceptance standard can refer to the classification standard of edible fungi [see VIII (IV)]. Immediately immerse in 2% dilute brine or 0.03% sodium pyrosulfite solution after acceptance, and prevent the mushroom body from floating out of the liquid level, and quickly transport it to the factory for treatment

2. Rinsing: rinsing is also called color protection. The harvested fresh mushrooms should be rinsed in the rinsing solution in time. The purpose is to wash away the sediment and impurities on the mushroom surface, isolate the air, inhibit the oxidation of tyrosine oxidase in the mushroom body, prevent the discoloration of the mushroom body, and maintain the normal color of the mushroom body; Inhibit the activity of protease, prevent the mushroom from continuing to grow and develop, and the Agaricus will no longer open its umbrella and maintain its original shape

rinsing solutions include clean water, dilute brine (2%) and dilute sodium pyrosulfite solution (0.03%). As sodium pyrosulfite is sulfite, which is harmful to human body, some countries have banned its use, and China stipulates that the residue of sulfur dioxide shall not exceed 0.002%. Therefore, immediately remove it after rinsing, put it into another rinsing tank with clean water, and rinse it clean

in order to ensure the rinsing effect, the rinsing solution should be replaced. Depending on the turbidity of the solution, it should be replaced once every 1 ~ 2 hours. The rinsing of edible fungi is generally carried out by hand, and the equipment is simple. It only needs to be equipped with a few cement tanks and brushing and stirring appliances. The more you know about the product, the more effective the operation of the machine is. The size of the rinsing pool depends on the need. Long and square pools can be used. It is best to install a movable metal water filter plate at the bottom of the pool. The cleaned sediment can sink into the lower part of the water filter plate at any time, so that the upper water is relatively clean. The bottom of the tank is equipped with a heavy hammer type sewage and sludge discharger

3. Pre Cooking: pre cooking is killing. After rinsing, remove the fresh mushrooms in time, and pre boil them with boiled dilute brine or dilute citric acid solution for about 10 minutes. The purpose is to destroy the enzyme activity in the mushroom body, discharge the air in the mushroom body tissue, and prevent the mushroom body from being oxidized and browning; Kill the mushroom tissue cells to prevent the umbrella bacteria from opening the umbrella; Destroy the structure of cell membrane and increase the permeability of membrane, which is conducive to the penetration of soup; Soften the mushroom tissue, shrink the mushroom body, enhance plasticity, facilitate canning, and reduce the damage of the cap. The pre cooking time should be controlled based on the thorough cooking. The identification method is: take out the mushroom and put it into cold water. Those who sink the mushroom are boiled thoroughly, and those who float on the water are not boiled thoroughly; Or bite the mushroom meat with your teeth. If it is crisp but not sticky, it is boiled thoroughly. If it is sticky but inelastic, it is not boiled thoroughly. If it is not cooked thoroughly, it will change color or even rot during storage; If the pre cooking is too long, some volatile components will be produced, which will make the iron can black

after pre cooking, immediately remove it, put it into cold water to cool, and terminate the further effect of heat treatment on mushroom tissue and nutrients

due to the sulfur-containing amino acids in the mushroom body of edible fungi, it is easy to react with iron to produce black iron sulfide when precooking. If it is a million level purchase. Therefore, the pre cooking container should be aluminum or stainless steel. The pre cooking equipment commonly used in small processing plants include cooking pots and dumping double pots. Larger manufacturers mostly use continuous pre cooking machines, with a production capacity of 2 ~ 3 tons per hour

4. Grading: in order to make the size of mushrooms in cans basically consistent, grading is still required before canning. Classification includes manual classification and mechanical classification. Small processing plants often use manual classification, using a simple tool - Classification Screen for classification. The grading screen is made of stainless steel, aluminum and hard wood. The size of the screen hole depends on the grading standard of the specific mushroom body. Table 5 shows the specifications of the mushroom grading screen

the common vibration of mechanical classification is also an important factor for the smooth progress of the experiment and the accuracy of the experimental results. The vibrating screen is also classified according to the size of the screen hole, which is suitable for the classification of mushroom bodies similar to spherical bodies, such as mushrooms, Hericium erinaceus, straw mushrooms, etc., and can be divided into about 1000 kg per hour

table 5 mushroom grading sieve standard

normal align=center> grade

normal align=center> sieve plate diameter hole (mm)

normal align=center> mushroom grain size (mm)

normal align=center>1

2

3

4

5

normal align=center>28

28

23

20

18

normal align=center> 28

25 ~ 28

23 ~ 25

20 ~ 23 auto parts industry

18 ~ 20

weight classifier is based on the weight of raw materials, which is not limited by the shape of raw materials. It is suitable for all kinds of edible fungi, but the classification efficiency is low