2. Key points of operation: Frozen food requires the freshness of food from raw materials to products, so it is appropriate to keep the working environment temperature stable during the production and processing in jiaozi, generally around 10℃. ! five
2. 1. Preparation of raw materials and auxiliary materials/10kY
2. 1. 1. Flour: Flour must be of high quality, white and high gluten, and jiaozi special flour can be used if conditions permit. Flour with deliquescence, caking, mildew, deterioration and damaged packaging cannot be used. For new flour, the existence of sulfhydryl compound, a powerful activator of protease, often affects the mixing quality of dough, thus affecting the quality of jiaozi products. To this end, we can add some old flour to the new flour or leave it for a period of time, so that the sulfhydryl groups in it are oxidized and lose their activity. Some can also add some quality improvers, but it will increase the manufacturing cost and is not easy to master and control, and it is usually inconvenient to use. The quality of flour directly affects the quality of jiaozi products, so we should pay special attention to it. pkF
2. 1.2. Raw meat: fresh meat or frozen meat that has passed veterinary hygiene inspection must be selected. It is forbidden to use frozen meat after repeated freezing and thawing, because this will not only reduce the nutritional value of meat, but also affect the water holding capacity and flavor of meat, thus affecting the quality of jiaozi. The thawing degree of frozen meat should be controlled moderately. Generally, it should be thawed at room temperature of about 20℃ 10 hour, and the central temperature should be controlled at 2-4℃. Raw meat must be boned and peeled before cleaning, lymph nodes and places with severe congestion should be trimmed, parts with abnormal color and smell should be removed, and hairy roots should be trimmed and degreased. Wash and drain the repaired lean fat with running water and twist it into granules for later use. 1! {mg-
2. 1.3. Vegetables: fresh and tender, except for dead leaves, rotten parts and roots, washed with running water and scalded with boiling water. Vegetables should be heated evenly and scalded moderately, not overcooked. Then quickly cool the vegetables to room temperature with cold water in a short time, drain them, grind them into particles, and squeeze out the vegetable water for later use. The amount of scalded vegetables depends on the output, and it should be used with scalding, not too scalding. If scalded vegetables are left for too long, they will be "rejuvenated" or thawed after use, which will affect the quality of jiaozi. 0h0Hb
2. 1.4. Accessories: sugar, salt, monosodium glutamate and other accessories should be made of high-quality products, and the inedible parts of onion, garlic, ginger and other accessories should be removed, washed with running water and chopped for later use. Pa]6b
2.2. Dough preparation: When kneading dough, it is necessary to measure accurately, add water quantitatively and mix moderately. According to the season and flour quality, control the water addition and mixing time. When the temperature is low, you can add more water to make the dough slightly softer. When the temperature is high, you can add less water or even some cold water at about 4℃ to make the dough harder, which is beneficial to the formation of jiaozi. If the dough is too thick, you can add more water to soften it, or add some starch, or add some hot water to improve this situation. The prepared dough can be covered with clean wet cloth to prevent the dough surface from air-drying and crusting, and let stand for about 5 minutes, so that the powder particles in the dough that have not absorbed enough water can fully absorb water, better generate a network of dough plates, improve the elasticity and moisture of the dough, and make the finished product more refreshing. Dough preparation technology is the key to the quality of finished products and the success of production operation. #J
2.3. Preparation of dumpling stuffing: The ingredients of dumpling stuffing should be exquisite, the measurement should be accurate and the stirring should be even. According to the quality of raw materials, the proportion of fat and thin, and the ambient temperature, the amount of water added to dumpling stuffing should be controlled well. Usually, it is more appropriate to control the ratio of fat to thin of meat at 2∶8 or 3∶7. Adding water: fresh meat > frozen meat > repeatedly frozen and thawed meat; No.4 meat > No.2 meat > pork belly > fat meat; When the temperature is high, less water is added than when the temperature is low. In hot summer, some cold water of about 2℃ must be added to reduce the temperature of dumpling stuffing, prevent it from spoilage and improve its water retention. After adding seasonings (that is, salt, monosodium glutamate, ginger, etc.), the ground stuffing must be filled with water. Add it first, then add water), otherwise the seasoning will not easily penetrate into the taste, it will not stick when stirred, and the water will not absorb it, so the ground stuffing made is not tender and delicious. After adding water, the stirring time must be enough to make the stuffing on the ground uniform and sticky, so that jiaozi products will be full and substantial. If the stirring is not sufficient, the stuffing and juice are easy to separate, and jiaozi is prone to loose package, rotten corners, cracking and juice outflow during molding, which leads to some undesirable phenomena such as oil leakage, stuffing leakage, and bottoming after jiaozi is cooked. If it is jiaozi with vegetable meat stuffing, add vegetables that have been scalded, ground and squeezed out of water on the basis of meat stuffing and mix well. _j
2.4. jiaozi system: At present, large-scale industrial production mostly adopts jiaozi molding machine to package jiaozi. Dumpling skin is an extremely important technical link in the production of jiaozi, which is directly related to the quality problems such as the shape, size, weight, thickness, skin filling ratio and so on. S{H
2.4. 1. The dumpling machine needs to be cleaned and debugged. Before work, you must check whether the machine is running normally and keep it clean, free of oil, meat, flour and other foreign substances; It is necessary to adjust the ground filler to a uniform and uninterrupted stable flow; The thickness, weight and size of dumpling skin should be adjusted to meet the product quality requirements. Generally speaking, jiaozi, whose skin weight is less than 55% and stuffing weight is more than 45%, is full in shape and moderate in size and thickness. In the process of wrapping, noodles (cut into strips) and fillings should be added in time to ensure the complete shape and uniform size of jiaozi. After the packaging system is completed, the machine should clean the relevant parts according to the specified requirements, and then assemble them in turn for later use after all cleaning. K
2.4.2. jiaozi shall be packed neatly and strictly, and there shall be no abnormal phenomena such as exposed stuffing, missing corners, flat belly, rotten head, deformation, wrinkling, small markings, lace jiaozi, not only connected together, but also jiaozi with different sizes at both ends. -Q，3
2.4.3. In the process of wrapping jiaozi, on the premise of ensuring that jiaozi does not stick to the mold, it is necessary to adjust the size of the leakage hole of the dry powder adjusting plate, reduce the falling amount of dry powder, reduce the stock of dry powder on the machine and the vibration of the vibrating screen, and minimize the dry flour attached to the jiaozi, so as to make the finished product of quick-frozen jiaozi fresh and tender in color and appearance. t，j
2.5. Setting: jiaozi packed by machine should be handled with care, and set by hand to keep the good shape of jiaozi. In plastic surgery, some unqualified jiaozi, such as flat belly, missing horn, cracking and abnormity, should be eliminated. When shaping, if the force is too strong or the holding method is unreasonable, the arrangement is too tight, and they squeeze each other, the shaped jiaozi will be flat, the deformation is not full, and even the juice will flow out and stick together, and the dumpling skin will crack. Plastic jiaozi should be sent to the quick freezing room for freezing in time. t
2.6. Quick-freezing: Quick-freezing of food means that food quickly passes through the maximum ice crystal formation zone (0 ~-4℃) in a short time (usually within 30 minutes). The ice crystals formed in quick-frozen food are small and almost all of them are dispersed in cells, and the cell rupture rate is low, so high-quality quick-frozen food can be obtained. Similarly, only through quick freezing, rather than slow freezing, can we get high-quality quick-frozen dumplings. When the central temperature of the quick-freezing room reaches-18℃, jiaozi is quickly frozen. At present, the quick-frozen products in China mostly adopt blast freezing, contact freezing and liquid nitrogen spray freezing. gf！
2.7. Bagging, weighing and packaging h
2.7. 1. bagging: quick-frozen dumplings can be bagged after freezing. When bagging, rotten, damaged and cracked jiaozi, two dumplings, three dumplings and many dumplings connected together should be removed, and deformed, landed, thawed and polluted jiaozi should also be removed. Do not load dough, dough and excessive flour. It is forbidden to pack jiaozi without freezing. rC； S
2.7.2. Weighing: accurate measurement is required, and the net content must not be lower than the requirements of national measurement standards and regulations. Measuring instruments should be calibrated frequently during work. Continuous wave (short for continuous wave)
2.7.3. After weighing, it can be exhausted and sealed. The sealing of the packaging bag should be tight, firm, flat and beautiful, and the production date and shelf life should be printed accurately and clearly. The packaging should be light, tidy, tightly sealed with adhesive tape, and the contents should be consistent with the logo, product name, production date and quantity of the outer packaging box. After packaging, it should be sent to the low-temperature warehouse in time. C
2.8. Low-temperature refrigeration: The packaged jiaozi must be refrigerated in a low-temperature warehouse at-18℃, and the temperature of the warehouse must be stable with the fluctuation not exceeding 1℃.