Tibet plateau yak jerky stir-frying method

Abstract

The invention relates to the technical field of food processing, in particular to a Tibetan plateau yak jerky stir-frying method. Comprising the following steps: preparing raw materials, namely carefully selecting Tibet plateau yak meat hind leg / shoulder lean meat which is qualified in quarantine; the method comprises the following steps: preparing a seasoning meeting national standard requirements, washing (15-25 DEG C flowing clear water to remove impurity blood water), cutting (cutting into blanks according to muscle fibers), marinating (precisely controlling the temperature and pressing in a pressure cooker until the yak meat strips are broken), cutting into strips (cutting into 5cm * 1cm * 1cm strips along the muscle fibers), drying / stir-frying (adding colza oil with the weight being 18-22% of that of the yak meat strips into the pot, stir-frying with soft fire at 120-150 DEG C, adding 2.5-3.5% of chili powder and other seasonings, turning over once every 30 seconds, and frying the yak meat strips for 2-3 hours. According to the method disclosed by the invention, the temperature and the water can be accurately controlled, more than or equal to 90% of protein in the yak meat is reserved, the product is chewy, easy to slug and long in aftertaste, the vacuum freezing storage shelf life reaches 12 months, and the process is simple, easy to scale, low in energy consumption and environment-friendly.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of food processing technology, in particular to a Tibetan plateau yak jerky frying method. BACKGROUND

[0002] Tibetan plateau yak meat, as a highland characteristic livestock product, grows in an alpine hypoxic environment above 3000 meters above sea level. Its meat is compact, high in protein content (≥20%), low in fat content (≤8%), and rich in minerals such as iron (≥3mg / 100g) and zinc (≥4mg / 100g) and essential amino acids for the human body, making it an excellent raw material for making jerky. Yak jerky is not only a traditional snack for local residents in Tibet, but also a cultural and travel consumer product that carries the culture of the plateau. In recent years, with the development of the cultural and travel industry and e-commerce, the market demand has grown at an average annual rate of over 15%. However, the current yak jerky production process still has many technical bottlenecks, which seriously restricts product quality and market expansion.

[0003] Traditional yak jerky production mainly uses baking and frying, both of which have insurmountable defects. The baking process mostly uses electric ovens or charcoal baking, and the core problem is uneven temperature distribution - the temperature difference between the top and bottom of the equipment cavity can reach 20-30℃, the bottom surface temperature of the meat in contact with the equipment is often over 180℃, while the top surface temperature is only 100-120℃. This temperature difference causes the surface layer of the meat to evaporate rapidly, forming a "hard shell", and it is difficult for the internal moisture to escape. The final product has a large fluctuation range of moisture content (8%-20%), and "undercooked" phenomenon often occurs below the hard shell. At the same time, high temperatures cause yak meat muscle fibers to over-contract and break, resulting in a rough texture that requires a force of ≥60N to chew (the industry's palatability standard is 30-45N), and the protein loss rate due to high-temperature denaturation is over 15%. In addition, during the baking process, meat fat is exuded and adheres to the inner wall of the equipment, causing not only nutritional waste but also increased cleaning difficulty. If not thoroughly cleaned, cross-contamination is likely to occur, and the risk of microbial contamination is high.

[0004] Although the frying process can shorten the processing time (usually 30-60 minutes), it requires high-temperature vegetable oil of 180-220℃. The unsaturated fatty acids (such as linoleic acid and alpha-linolenic acid) in yak meat can easily oxidize and decompose at this temperature, producing harmful substances such as aldehydes and ketones (e.g., acrylamide content can reach 0.3mg / kg, exceeding the safety limit of 0.15mg / kg), which poses a threat to food safety. High temperatures also cause the surface layer of the meat to carbonize rapidly, forming a charred layer that masks the natural flavor of yak meat. The internal moisture vaporizes rapidly, causing the meat structure to contract tightly, resulting in a hardness of 60-80N upon entry, which requires excessive chewing and does not meet the needs of modern consumers for "easy residue". At the same time, the oil content of the fried meat is as high as 25%-35%, far exceeding the standard of "low oil food ≤20%" in the "General Principles for Nutritional Labeling of Prepackaged Snack Foods", resulting in a strong greasy sensation when consumed, which limits the choices of older consumers and those seeking to reduce fat.

[0005] In addition to the above mainstream process, some small enterprises still use natural drying process, relying on highland sunshine (daily sunshine ≥8 hours) and wind drying, although it can reduce energy consumption, but is greatly affected by weather - rainy weather (Tibet Plateau annual rainfall about 60 days) is easy to cause meat mildew, mold detection rate more than 10 %; strong sunlight makes the surface of the meat hardening, vitamin B (such as vitamin B1) loss rate more than 30 %, and the drying cycle is as long as 3-5 days, the production efficiency is very low (single batch yield ≤50 kg), it is difficult to meet the market demand (single production line daily demand ≥500 kg).

[0006] In the prior art, although there are attempts to improve the drying process, such as using 60-70℃ hot air drying for 4-6 hours, but there are still deficiencies: hot air directly blowing the surface of the meat, which is easy to cause the surface water evaporation too fast to form "crust effect", the internal water migration is blocked, and the final product is "dry outside and soft inside", the water uniformity deviation is more than 5 %; and long time medium temperature heating makes the meat taste still hard (chewing force ≥50N), and the delicacy is insufficient, at the same time, the energy consumption is high (power consumption per kg product ≥2.5kWh), which does not meet the low-carbon production trend.

[0007] In summary, the current yak jerky production process generally has four core problems: "poor taste (hard, not easy to crumble, short aftertaste), serious nutrient loss, low production efficiency, and high food safety risk", which cannot meet the needs of consumers for high-quality, safe and characteristic yak jerky. Therefore, it is of great practical significance and economic value to develop a yak jerky frying method that can precisely control moisture and temperature, protect muscle fiber integrity, improve flavor levels and is suitable for large-scale production, to promote the upgrading of Tibet plateau characteristic food industry, ensure food safety and improve product market competitiveness. SUMMARY

[0008] In view of the problems in the prior art, the present application provides a Tibet plateau yak jerky frying method, which precisely controls the selection of raw materials, process parameters (temperature, time, seasoning ratio) and operation process, to achieve the following objectives: 1. protect the integrity of yak muscle fibers, make the product chewy, easy to crumble, soft in mouth and long aftertaste; 2. precisely control the moisture (9%-16%) and oil content (≤20%), avoid nutrient loss (protein retention rate ≥90%); 3. reduce food safety risk, no harmful substances detected, microbial indicators meet the standards; 4. simplify the process, reduce energy consumption, suitable for large-scale production (single production line daily output ≥500 kg), prolong the shelf life of the product (vacuum frozen storage for 12 months).

[0009] The technical scheme adopted by the application to solve the technical problems is: a Tibet plateau yak jerky frying method, comprising the following steps: Step (1) raw material preparation: ① meat selection: select the health quarantine qualified Tibetan plateau yak meat, preferentially select yak hind leg or shoulder lean meat, remove fat muscle membrane, broken bone, remove proportion ≥95%, ensure meat purity; ② seasoning preparation: prepare seasoning according to taste requirements, including 1%-2% salt, 2.5%-3.5% chili powder, 0.8%-1.2% chicken essence, 0.8%-1.2% sugar, 0.4%-0.6% five spice powder, 1.8%-2.2% cooked sesame, 1.8%-2.2% pepper grains (red pepper and green pepper 1:1 mixed) based on the weight of yak meat strips, remove impurities after the seasoning is sieved through 80 mesh and mixed evenly; Step (2) rinse: rinse the removed yak meat with 15-25℃ flowing clean water for 5-10 minutes, turn over every 1 minute to remove impurities and blood water; Step (3) segmentation: cut the yak meat into blanks with thickness 1cm, width 1cm and length 5±0.1cm according to the muscle fiber direction; Step (4) marinating: directly put the fresh / cold fresh meat blanks into a pressure cooker, add clean water 2cm higher than the meat blanks, add 10g ginger slices, 5g white onion, 20mL cooking wine according to 1000g meat blanks, cook at 0.1-0.15MPa pressure and 115-125℃ temperature for 15-25 minutes until the center temperature ≥75℃, and cool to room temperature; Step (5) cutting: cut into strips with length 5.0±0.2cm, width 1.0±0.2cm and height 1.0±0.2cm along the muscle fiber; Step (6) drying / stir-frying: add 18%-22% first class rapeseed oil to the frying pan, put the meat strips into the cold oil (25-30℃), fry at low heat 120-150℃ until the surface is brown, add the prepared seasoning, turn over every 30 seconds, fry for 14-21 minutes until the moisture is 9%-16% and there is no visible soluble seasoning, turn off the heat and cool to room temperature; Step (7) packaging: use PA / PE composite film vacuum or nitrogen packaging, each bag weighs 50-100g, vacuum degree-0.08 to-0.1MPa, heat seal at 180-200℃ for 2-4 seconds; Step (8) sterilization: use 118-123℃, 25-35 minutes high temperature steam sterilization or 5-7kGy irradiation sterilization, cool to below 40℃; Step (9) inspection: detect appearance, taste, moisture, microorganisms (total number of colonies ≤100cfu / g, no detection of escherichia coli) and nutrition indicators, and the qualified product is the finished product.

[0010] Specifically, in step (1) ①, the yak meat is selected from Naqu and Shigatse City, Tibet, the fat content of the meat is ≤5%, and the fat content after removal is ≤3%.

[0011] Specifically, the frozen yak meat in step (4) needs to be pre-cold stored at 4 DEG C for 12-24 hours, and the center temperature is less than or equal to 5 DEG C after thawing, and then halogen is boiled.

[0012] Specifically, in step (6), the chili powder is 80 mesh Sichuan chao tian pepper powder, the cooked sesame is 40 mesh white sesame, and the pepper grain is a mixture of Sichuan Han Yuan red flower pepper and Yunnan Zhaotong green flower pepper, and the red flower pepper and the green flower pepper are mixed at a ratio of 1:1.

[0013] Specifically, in step (6), the stainless steel frying pan is used for frying, the diameter is 70-90 cm, the depth is 25-35 cm, the infrared temperature instrument is used for real-time monitoring of the temperature, and the temperature difference is less than or equal to 5 DEG C.

[0014] Specifically, in step (7), the PA / PE composite film has a thickness of 0.08-0.12 mm, an oxygen permeability of less than or equal to 5 cm3 / (m2*24h*0.1MPa), and a water vapor permeability of less than or equal to 2 g / (m2*24h).

[0015] Specifically, in step (8), the high-temperature steam sterilization adopts spray cooling, and the cooling time is 10-15 minutes to avoid deformation of the packaging film.

[0016] Specifically, in step (2), the flow rate of the flowing clean water is 0.4-0.6 m / s, and there is no blood water residue on the surface of the meat after washing, and the transparency of the clean water does not change obviously.

[0017] Specifically, in step (5), the sterile strip cutting machine is used for cutting, and every 100 strips are checked by vernier caliper, and the size qualified rate is greater than or equal to 98%.

[0018] Specifically, in step (9), the protein retention rate is greater than or equal to 90%, and no harmful substances such as aldehydes and ketones are detected.

[0019] The beneficial effects of the present application are: The taste quality is significantly improved: the core process of "cold oil into the pot + small fire slow frying + every 30 seconds stirring" is adopted, the meat strip is evenly heated (temperature difference is less than or equal to 5 DEG C), water is slowly evaporated (water uniformity deviation is less than or equal to 1%), and the integrity of yak muscle fibers is effectively protected - the chewing force of the finished product is controlled in 30-45N, reaching the "tough but not hard" state, and the residue is easily softened, the entry is soft, and the aftertaste time is greater than or equal to 5 minutes, solving the problem of "hard, rough and not easy to soften" in the traditional process; The nutrient retention rate is high: the frying temperature (120-150 DEG C) and time (14-21 minutes) are accurately controlled to avoid nutrient loss caused by high temperature, so that the protein retention rate is greater than or equal to 90%, the vitamin B1 retention rate is greater than or equal to 70%, the mineral substances (iron and zinc) are almost not lost, and the rapeseed oil usage is controlled in 18%-22%, the oil content of the finished product is less than or equal to 20%, which meets the health food standard; Food safety index is excellent: from raw material quarantine (qualification certificate), production environment sterilization (operation table 75% ethanol disinfection), process sterilization (high temperature steam / irradiation) to finished product inspection (microorganism, harmful substance detection), forming whole process safety control - finished product colony total number ≤100 cfu / g, no escherichia coli and salmonella are detected, no harmful substances such as aldehydes and ketones are detected, and the food safety risk is significantly reduced; High production efficiency and environmental protection: simple process operation (no complex equipment is needed), single production line daily output ≥500 kg, which is 10 times higher than natural drying; The energy consumption of the frying process is low (the power consumption of each kg of product is ≤1.5 kWh, which is reduced by 40% compared with hot air drying), and there is no waste water and waste gas emission, which meets the low-carbon environmental protection trend; Long shelf life: vacuum packaging (PA / PE film) combined with frozen storage (-18℃), the shelf life of the finished product is up to 12 months, which is 1 times longer than that of traditional baking products (6 months), which is convenient for market circulation and storage. BRIEF DESCRIPTION OF DRAWINGS

[0020] The application will be further described below in combination with the drawings and examples.

[0021] Figure 1 A flow chart of a Tibetan plateau yak jerky frying method provided by the application. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative characteristics, purposes and effects realized by the application easy to understand, the application will be further described below in combination with specific embodiments.

[0023] As shown in the drawings, Figure 1 A Tibetan plateau yak jerky frying method provided by the application, the specific steps are as follows: I. Raw material preparation 1.1 Meat selection: select yak meat from core production areas such as Naqu and Shigatse City in Tibet, which has passed quarantine, and preferentially select yak hind leg or shoulder lean meat - the part is tight and has low fat content (≤5%), which is the best raw material for making jerky. Use stainless steel knives to manually or mechanically remove fat muscle membrane, broken bones and internal fat from the surface of the meat product, and the removal ratio is ≥95%. After removal, randomly sample and detect to ensure that the fat content in the meat product is ≤3% and there is no visible impurities, so as to avoid too much fat in subsequent processing which causes greasy feeling.

[0024] 1.2 Seasoning preparation: According to the market demand for spicy and five-spice flavors, the seasoning is prepared in accordance with GB-2760 "National Food Safety Standard Food Additive Use Standard" and GB / T-30382 "Good Manufacturing Practice for Condiments". The seasoning ratio is based on the weight of the yak strips: 1%-2% salt (purity ≥ 99.5%, avoid impurities affecting taste), 2.5%-3.5% chili powder (preferably Sichuan chilies, ground and sieved through an 80-mesh sieve to ensure uniform spiciness), 0.8%-1.2% chicken essence (sodium glutamate content ≥ 40% to enhance umami flavor), 0.8%-1.2% white sugar (white granulated sugar, purity ≥ 99.8% to neutralize the heat and enhance the flavor), 0.4%-0.6% five-spice powder (made from star anise, cassia, cloves, etc. in a ratio of 3:2:1:1:1, sieved through a 60-mesh sieve to remove lumps), 1.8%-2.2% roasted sesame seeds (white sesame seeds roasted and cooled, sieved through a 40-mesh sieve to add aroma and texture), 1.8%-2.2% whole Sichuan pepper (red Sichuan pepper from Han Yuan, Sichuan, and green Sichuan pepper from Zhaotong, Yunnan, mixed in a 1:1 ratio, used whole to retain the spicy flavor). Sieve the above seasonings through an 80-mesh sieve to remove lumps and impurities, then mix them evenly according to the proportions and set aside.

[0025] II. Rinsing Place the trimmed yak pieces (single piece weight 500-1000g for uniform rinsing) in a sterile stainless steel rinsing tank, and use flowing clean water at 15-25°C to rinse. The water flow speed is controlled at 0.4-0.6m / s (too slow water flow may leave impurities, too fast water flow may cause the meat surface to break), and the rinsing time is 5-10 minutes. During the rinsing process, manually or mechanically turn the meat pieces every 1 minute to ensure that the impurities and blood in the meat surface and muscle fiber gaps are completely removed. After rinsing, observe that there is no blood residue on the meat surface, and the transparency of the rinsing water does not change significantly. Drain the water (draining time ≤ 2 minutes to avoid excessive water absorption affecting subsequent marinating) and set aside.

[0026] III. Cutting Place the rinsed yak pieces on a sterile operating table disinfected with 75% ethanol, and cut them according to the direction of the muscle fibers (cut along the longitudinal direction of the muscle fibers to avoid breaking the muscle fibers, which may cause the dried meat to be easily broken). Use a sterile slicing machine to cut the meat pieces into 1cm thick slices, then cut them into 1cm wide and 5±0.1cm long blanks along the transverse direction. The blank size needs to be uniform to ensure uniform heating and consistent cooking during subsequent marinating. The cut pieces should not have obvious broken pieces (broken piece ratio ≤ 2%) and be set aside.

[0027] IV. Marinating If frozen yak meat is selected, it needs to be thawed in advance in a 4°C refrigerated environment for 12-24 hours. After thawing, the center temperature of the meat product is detected to be ≤5°C (to avoid excessive thawing and bacterial growth). If it is fresh or chilled meat (stored at 0-4°C for ≤24 hours), it can be used directly. After the meat is cut into pieces, it is placed in a sterile stainless steel pressure cooker, and water is added (the water level should be 2 cm higher than the meat pieces to ensure complete immersion). Then, 10 g of ginger slices (2 mm thick) are added for deodorization, 5 g of white onion (cut into 3 cm pieces for flavor enhancement), and 20 mL of cooking wine (with an alcohol content of ≥10% to further remove odors without affecting the natural flavor of the meat product). Cover the pressure cooker lid and seal it. When the pressure rises to 0.1-0.15 MPa, start timing. Maintain the pressure and temperature at 115-125°C for 15-25 minutes (if the pressure is too low and the temperature is insufficient, the meat product will not be easily cooked, and if the pressure is too high and the time is too long, the muscle fibers will easily break). Monitor the pressure gauge in real time during the braising process to ensure stable pressure (pressure fluctuation ≤0.01 MPa). After braising, slowly release the pressure to normal pressure (release time ≥5 minutes to avoid sudden pressure drop causing meat expansion and damage), open the lid and remove the meat pieces. Use a food-grade temperature probe to detect the center temperature of the meat pieces to ensure that it reaches ≥75°C (the standard for cooking and killing most pathogenic bacteria). Then, place the meat pieces on a sterile cooling rack and cool them to room temperature (20-25°C, cooling time 30-40 minutes to avoid rapid cooling causing meat skin shrinkage). The meat pieces are ready for use.

[0028] Five, cutting into strips Place the cooled braised meat pieces on a sterile cutting machine and strictly cut them along the muscle fiber direction (cut longitudinally along the muscle fibers to preserve the integrity of the muscle fibers and improve the chewiness of the jerky). The cutting size is 5.0±0.2 cm long x 1.0±0.2 cm wide x 1.0±0.2 cm high. During cutting, every 100 pieces are checked with a vernier caliper to ensure that the size is ≥98% (a large size deviation will cause uneven heating and large water content differences during subsequent stir-frying). The cut meat pieces have no obvious bending or breaking and are ready for use.

[0029] Six, drying / stir-frying (core step) A sterile stainless steel frying pan (70-90 cm in diameter, 25-35 cm in depth, flat bottom to ensure even heating) is used for the operation. First, add first-grade rapeseed oil (complying with GB-1536 "Rapeseed Oil" standard, high smoke point, not easy to produce harmful substances at high temperature) to the frying pan, the amount being 18%-22% of the weight of the beef strips (too little oil and the beef strips will stick to the pan, too much oil and the finished product will exceed the oil content standard). When the temperature of the rapeseed oil drops to 25-30°C (cold oil state, to avoid the surface of the beef strips from quickly charring due to hot oil), slowly put the cut beef strips into the frying pan, avoiding oil splashing (can be put in batches, each batch weighing ≤1 / 3 of the capacity of the frying pan). Start heating with a small fire, and monitor the temperature at the bottom of the frying pan and the surface of the beef strips in real time through an infrared thermometer, controlling the frying temperature at 120-150°C (too low temperature and the water will evaporate slowly, low efficiency, too high temperature and the muscle fibers will be easily damaged, poor taste). During the frying process, the beef strips are evenly stirred along the bottom of the frying pan every 30 seconds with a sterile stainless steel spatula (moderate stirring range to avoid breaking the beef strips), ensuring even heating of the beef strips.

[0030] When the surface of the beef strips turns into a uniform brown color (frying time is about 5-8 minutes, adjusted according to the number of beef strips), slowly add the mixed seasoning prepared in advance to the frying pan (added in 2-3 times to avoid clumping of the seasoning), and continue to stir-fry with a small fire. After adding the seasoning, maintain a stirring frequency of every 30 seconds to ensure that the seasoning is evenly attached to the surface of the beef strips and there are no visible clumps of soluble seasoning (such as salt, sugar). The total frying time is controlled at 14-21 minutes, and 5 minutes before the end of frying, randomly sample and test the moisture content of the beef strips with a Karl Fischer moisture rapid tester - when the moisture content is reduced to 9%-16%, immediately turn off the fire (too high moisture content and the shelf life is short, too low moisture content and the taste is too hard). Take out the fried beef jerky and place it in a sterile cooling tray, and naturally cool it to room temperature (20-25°C, cooling time 20-30 minutes, to avoid rapid cooling leading to crystallization of the seasoning), ready for use.

[0031] Seven, packaging PA / PE composite film is used as the packaging material (thickness 0.08-0.12 mm, oxygen transmission rate ≤5 cm³ / (m²·24 h·0.1 MPa), water vapor transmission rate ≤2 g / (m²·24 h), effectively blocking oxygen and moisture, prolonging shelf life). The cooled yak jerky is packaged using a sterile vacuum packaging machine or a nitrogen filling packaging machine, with each bag weighing 50-100 g (consistent with the mainstream specifications in the market, facilitating single consumption). If vacuum packaging, the vacuum degree is set to -0.08 to -0.1 MPa (too low vacuum degree results in poor preservation effect, and too high vacuum degree causes the jerky to deform under pressure), the heat sealing temperature is 180-200°C, and the heat sealing time is 2-4 seconds (too low temperature and short time result in poor sealing, and too high temperature and long time cause the packaging film to char); if nitrogen filling packaging, the nitrogen purity is ≥99.99%, and the filling amount is appropriate with the bag slightly inflated (avoiding squeezing the jerky). During packaging, every 10 bags are randomly sampled for inspection to ensure that the packaging is sealed well (no air leakage or bag swelling), there is no visible foreign matter in the bag, and a standby bag is prepared.

[0032] Eight, sterilization High-temperature steam sterilization or irradiation sterilization is used, and the production needs are selected: High-temperature steam sterilization: the packaged yak jerky is placed in a sterile high-temperature steam sterilization kettle, the sterilization temperature is set to 118-123°C, the sterilization time is 25-35 minutes, and the steam pressure is controlled at 0.12-0.15 MPa (too low temperature and too short time result in incomplete sterilization, and too high temperature and too long time result in poor jerky taste). After sterilization, the jerky is cooled to below 40°C using cold water spraying (cooling time 10-15 minutes, to avoid shrinkage and deformation of the packaging film due to large temperature difference); Irradiation sterilization: the packaged yak jerky is sent to a cobalt-60 irradiation room, the irradiation dose is controlled at 5-7 kGy (too low dose results in incomplete sterilization, and too high dose may produce irradiation odor), and the jerky is uniformly irradiated during irradiation. No irradiation residue is detected after irradiation.

[0033] Nine, inspection The sterilized yak jerky is subjected to comprehensive inspection, and the inspection items and standards are as follows: Appearance: 10 bags of product are randomly selected and observed after opening. The jerky is uniformly brown (lightness can be adjusted slightly for taste), with a small amount of sesame and Sichuan pepper attached to the surface, no burnt, moldy, or worm-eaten phenomenon, complete shape, and broken strip ratio ≤5%; Taste: a 10-person professional tasting group (trained in sensory evaluation) is organized, and a 5-point rating system is used (5 points for the best). Chewiness ≥4 points, easy residue ≥4 points, softness at the entrance ≥4 points, aftertaste time ≥5 minutes, and comprehensive taste score ≥4 points; Moisture content: Karl Fischer method was used to detect, randomly sampled 3 times, the average value should be in the range of 9%-16%, and the deviation of 3 times detection results was ≤1%; Microbial indicators: According to GB-4789.2, the total number of colonies was detected to be ≤100 cfu / g, according to GB-4789.3, no E. coli was detected, and according to GB-4789.4, no Salmonella was detected; Nutrition and safety indicators: Kjeldahl method was used to detect protein content ≥28%, protein retention rate ≥90% (compared to raw material yak meat); gas chromatography was used to detect harmful substances such as aldehydes and ketones, no harmful substances were detected; oil content ≤20% (complying with low oil food standards).

[0034] After all test items were qualified, it was the finished product of Tibetan Plateau yak jerky.

[0035] Example one Raw material preparation 1.1 Meat selection: Selecting yak meat from Tibet Naqu City that has passed quarantine, using yak hind leg lean meat, the fat content of which is 4.2%, meeting the raw material requirements. Stainless steel knives were used to manually remove fat muscle membranes and broken bones, with a removal ratio of 96%. After removal, random sampling detection showed that the fat content was 2.8% and there were no visible impurities, ready for use.

[0036] 1.2 Spice preparation: Spices were prepared according to the spicy taste, with the weight of yak strips (10 kg in this experiment) as the basis, and the ratio was: salt 1.0% (100 g, purity 99.6%), chili powder 2.5% (250 g, Sichuan hot pepper ground, 80 mesh sieve), chicken essence 0.8% (80 g, sodium glutamate content 42%), sugar 0.8% (80 g, white granulated sugar purity 99.8%), five-spice powder 0.4% (40 g, star anise 30%, cassia bark 20%, clove 10%, fennel 20%, bay leaf 20%, 60 mesh sieve), cooked sesame seeds 1.8% (180 g, white sesame seeds were fried, cooled, and 40 mesh sieve), and Sichuan pepper grains 1.8% (180 g, Han Yuan red pepper 90 g + Zhaotong green pepper 90 g). The spices were mixed evenly after being sieved through an 80 mesh sieve and removing lumps, ready for use.

[0037] Operation process and technical indicators 2.1 Rinse: Put the removed yak meat pieces (500 g each) into a sterile stainless steel rinse tank, rinse with 15℃ flowing water, flow rate 0.4 m / s, time 5 minutes. Turn over every 1 minute, and after rinsing, the meat product has no blood water residue, the water is transparent, and it is drained for 2 minutes, ready for use.

[0038] 2.2 Cutting: On a 75% ethanol disinfected operating table, cut 1 cm thick slices along the muscle fiber length, then cut 1 cm wide and 5.0 cm long blanks, the blanks have no broken pieces, ready for use.

[0039] 2.3 boiling: fresh yak meat (0-4℃ storage for 12 hours) was selected, the blank was put into a pressure cooker, and clean water was added to cover 2 cm, 10 g of fresh ginger slices, 5 g of green onion, and 20 mL of cooking wine were added according to 1000 g of meat blank. Seal and heat to a pressure of 0.10 MPa and a temperature of 115℃, and cook for 15 minutes. Release the pressure to normal pressure, take out and detect the center temperature of 76℃, cool to 25℃ (30 minutes), and reserve.

[0040] 2.4 cutting: sterile cutting machine was used to cut along the muscle fiber, the size was 5.0 cm x 1.0 cm x 1.0 cm, every 100 strips were taken for inspection, the size qualified rate was 99%, and the reserved.

[0041] 2.5 drying / frying: a 80 cm diameter stainless steel frying pan was used, 18% rapeseed oil (1.8 kg, first grade rapeseed oil) was added, and the meat strips were put into the cold oil (25℃). Small fire heating to 120℃, turn over every 30 seconds, fry for 6 minutes until the surface is brown, add mixed seasoning, continue to fry for 8 minutes (total 14 minutes). Test the moisture content 5 minutes before the end, stop the fire when it reaches 9.0%, cool to 25℃ (20 minutes), and reserve.

[0042] 2.6 packaging: 0.08 mm PA / PE composite film (oxygen transmission rate 4.5 cm³ / (m²·24h·0.1MPa)) was used for vacuum packaging, 50 g per bag, vacuum degree-0.08 MPa, heat sealing temperature 180℃, 2 seconds. Every 10 bags were taken for inspection, no air leakage, and reserved.

[0043] 2.7 sterilization: high temperature steam sterilization, temperature 118℃, pressure 0.12 MPa, time 25 minutes. Spray with cold water to cool to 38℃ (10 minutes), and reserve.

[0044] 2.8 inspection: appearance: 10 bags were light brown, with sesame and pepper particles on the surface, no burnt paste, and 1% broken strips; taste: the product evaluation group scored, chewy 4.2 points, easy to soften 4.3 points, soft 4.1 points, aftertaste 6 minutes, comprehensive 4.2 points; moisture: Karl Fischer method was used for detection, 3 times, average 9.0%, deviation 0.5%; microorganisms: total bacterial count 45 cfu / g, no escherichia coli and salmonella were detected; nutritional safety: protein 28.5%, retention rate 91%, no harmful substances were detected, and oil content 19.2%.

[0045] The finished product is qualified and meets the quality standards.

[0046] Example two raw material preparation 1.1 Meat selection: Select yak meat from the Shigatse City quarantine, select the shoulder lean meat, fat content 4.8%. Mechanical removal of fat muscle membrane, broken bone, removal ratio 95%, after repair, the fat content is 2.9%, no impurities, ready for use.

[0047] 1.2 Spice preparation: 10 kg yak meat strip as a benchmark, ratio: salt 1.5% (150 g, purity 99.7%), chili powder 3.0% (300 g, chaitian pepper 80 mesh), chicken essence 1.0% (100 g, sodium glutamate 45%), sugar 1.0% (100 g, white granulated sugar), five-spice powder 0.5% (50 g, traditional formula 60 mesh), cooked sesame 2.0% (200 g, white sesame 40 mesh), Sichuan pepper 2.0% (200 g, red / green 100 g each). Mix through 80 mesh sieve, ready for use.

[0048] Operation process and technical indicators 2.1 Rinse: meat block (800 g per piece) is rinsed with 20℃ flowing water, flow rate 0.5 m / s, time 7 minutes, turn over every 1 minute, no blood water after rinsing, drain for 1.5 minutes, ready for use.

[0049] 2.2 Cutting: cut 1 cm thick slices, then cut 1 cm wide, 5.0 cm long blanks, no broken pieces, ready for use.

[0050] 2.3 Marinating: fresh meat blanks are put into a pressure cooker, add clean water to cover 2 cm, add ginger, white onion, cooking wine. Pressure 0.12 MPa, temperature 121℃, cook for 20 minutes. Center temperature 78℃, cool to 23℃ (35 minutes), ready for use.

[0051] 2.4 Cutting: cut the size of 5.1 cm x 1.1 cm x 1.1 cm, the qualified rate of sampling inspection is 98.5%, ready for use.

[0052] 2.5 Drying / stir-frying: 80 cm frying pan, add 20% rapeseed oil (2.0 kg), put meat strips in cold oil (28℃). Small fire 135℃, turn over every 30 seconds, fry for 7 minutes to brown, add spices and fry for 10 minutes (total 17 minutes). Moisture detection 12.0% stop fire, cool to 23℃ (25 minutes), ready for use.

[0053] 2.6 Packaging: 0.10 mm PA / PE film (oxygen transmission rate 4.0 cm³ / (m²・24h・0.1 MPa)) vacuum packaging, 75 g per bag, vacuum degree -0.09 MPa, heat sealing 190℃, 3 seconds, no air leakage, ready for use.

[0054] 2.7 Sterilization: high temperature steam 121℃, 0.13 MPa, 30 minutes, cool to 35℃ (12 minutes), ready for use.

[0055] 2.8 Inspection: Appearance: Brown uniform, sesame pepper grain obvious, no burnt paste, broken strip 2%; Taste: chewy 4.5 points, easy to soften residue 4.6 points, soft 4.4 points, aftertaste 7 minutes, comprehensive 4.5 points; Moisture: mean 12.0%, deviation 0.8%; Microorganisms: total number of colonies 38 cfu / g, no pathogenic bacteria detected; Nutritional safety: protein 29.2%, retention rate 92%, no harmful substances detected, oil content 18.5%.

[0056] Finished product qualified.

[0057] Example Three Raw material preparation 1.1 Meat selection: Tibet Naqu City quarantine yak meat, hind leg lean meat, fat content 4.5%. 97% fat muscle membrane was artificially removed, and the fat content after repair was 2.7%, ready for use.

[0058] 1.2 Spice preparation: 10 kg of meat strip as reference, salt 2.0% (200 g), chili powder 3.5% (350 g), chicken essence 1.2% (120 g), sugar 1.2% (120 g), five-spice powder 0.6% (60 g), cooked sesame 2.2% (220 g), pepper grain 2.2% (220 g), sieve mixed, ready for use.

[0059] Operation process and technical indicators 2.1 Rinse: 25℃ flowing water, flow rate 0.6m / s, time 10 minutes, no blood water after turning, drain for 2 minutes, ready for use.

[0060] 2.2 Segmentation: cut 1cm thick pieces, 5.1cm long blanks, ready for use.

[0061] 2.3 Marinating and boiling: frozen meat 4℃ thawed for 20 hours (center temperature 4℃), into high pressure pot, pressure 0.15MPa, 125℃, boiled for 25 minutes, center temperature 80℃, cooled to 22℃ (40 minutes), ready for use.

[0062] 2.4 Cutting: size 4.9cm×0.9cm×0.9cm, qualified rate 99%, ready for use.

[0063] 2.5 Drying / stir-frying: 90cm frying pan, add 22% rapeseed oil (2.2kg), put meat strips in cold oil 30℃. Small fire 150℃, fry for 8 minutes to brown, add spices and fry for 13 minutes (total 21 minutes), moisture 16.0% stop fire, cool to 22℃ (30 minutes), ready for use.

[0064] 2.6 Packaging: 0.12mm PA / PE film, nitrogen filling packaging (nitrogen purity 99.99%), 100g per bag, no air leakage, ready for use.

[0065] 2.7 Sterilization: irradiation sterilization 6 kGy, no residue, standby.

[0066] 2.8 Inspection: Appearance: dark brown, no burnt, broken strip 3%; Taste: chewy 4.3 points, easy residue 4.4 points, soft 4.2 points, aftertaste 6.5 minutes, comprehensive 4.3 points; Moisture: 16.0%, deviation 0.9%; Microorganisms: total number of colonies 42 cfu / g, no pathogenic bacteria detected; Nutritional safety: protein 28.8%, retention rate 90%, oil content 19.8%.

[0067] Finished product qualified.

[0068] Example Four Raw material preparation 1.1 Meat selection: Tibet Shigatse City quarantine yak meat, shoulder lean meat, fat 4.6%, 96% fat removed, 3.0% after repair, standby.

[0069] 1.2 Spice preparation: 10 kg of meat strip as reference, salt 1.2% (120 g), pepper powder 2.8% (280 g), chicken essence 0.9% (90 g), sugar 0.9% (90 g), five-spice powder 0.45% (45 g), cooked sesame 1.9% (190 g), Sichuan pepper 1.9% (190 g), mix standby.

[0070] Operation process and technical indicators 2.1 Rinse: 18°C water, flow rate 0.45 m / s, time 6 minutes, no blood water, standby.

[0071] 2.2 Segmentation: 5.0 cm long blank, standby.

[0072] 2.3 Marinating: fresh meat, 0.11 MPa, 118°C, high pressure pot, cook for 18 minutes, center 77°C, cool to 24°C (32 minutes), standby.

[0073] 2.4 Cutting: 5.0 cm x 1.0 cm x 1.0 cm, qualified rate 98.8%, standby.

[0074] 2.5 Drying / stir-frying: 80 cm frying pan, add 19% rapeseed oil (1.9 kg), cold oil 26°C, small fire 125°C, fry for 6.5 minutes to brown, add spices and fry for 8.5 minutes (total 15 minutes), moisture 10.0% stop fire, cool to 24°C (22 minutes), standby.

[0075] 2.6 Packaging: 0.09 mm PA / PE film vacuum packaging, 50 g / bag, vacuum degree -0.085 MPa, heat sealing 185°C, 2.5 seconds, standby.

[0076] 2.7 Sterilization: 120°C steam, 0.12 MPa, 28 minutes, cooling 37°C, standby.

[0077] 2.8 Inspection: Appearance: light brown, broken strip 1.5%; Taste: 4.4 points in total; Moisture: 10.0%; Microorganisms: total number of colonies 35 cfu / g; Nutrition: protein 29.0%, retention rate 91.5%, oil content 18.8%.

[0078] Finished product qualified.

[0079] Example Five Raw material preparation 1.1 Meat selection: Tibet Naqu City quarantine yak meat, hind leg lean meat, fat 4.3%, 95.5% fat removed, 2.9% after repair, standby.

[0080] 1.2 Spice preparation: 10 kg of meat strip base, salt 1.8% (180 g), chili powder 3.2% (320 g), chicken essence 1.1% (110 g), sugar 1.1% (110 g), five-spice powder 0.55% (55 g), cooked sesame 2.1% (210 g), Sichuan pepper 2.1% (210 g), mix standby.

[0081] Operation process and technical indicators 2.1 Rinse: 22°C water, flow rate 0.55 m / s, time 9 minutes, no blood water, standby.

[0082] 2.2 Segmentation: 5.0 cm long blank, standby.

[0083] 2.3 Marinating: frozen meat thawed for 16 hours (center 5°C), high pressure pot 0.13 MPa, 122°C, cooked for 22 minutes, center 79°C, cooled to 23°C (38 minutes), standby.

[0084] 2.4 Cutting: 4.9 cm x 1.1 cm x 1.0 cm, qualified rate 98.6%, standby.

[0085] 2.5 Drying / stir-frying: 90 cm frying pan with 21% rapeseed oil (2.1 kg), cold oil 29°C, small fire 140°C, stir-fry for 7.5 minutes to brown, add spices and stir-fry for 11.5 minutes (total 19 minutes), moisture 14.0% stop fire, cooling 23°C (28 minutes), standby.

[0086] 2.6 Packaging: 0.11 mm PA / PE film packaging with nitrogen, 75 g / bag, standby.

[0087] 2.7 Sterilization: irradiation 7 kGy, standby.

[0088] 2.8 Inspection: Appearance: brown, broken strip 2.5%; Taste: 4.3 points in total; Moisture: 14.0%; Microorganisms: total number of colonies 40 cfu / g; Nutrition: protein 28.7%, retention rate 90.5%, oil content 19.5%.

[0089] The finished product is qualified.

[0090] The above shows and describes the basic principles, main features and advantages of the present application. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A Tibetan Plateau yak jerky frying method, characterized by, Includes the following steps: Step (1) Raw material preparation: ① Meat selection: Select Tibetan plateau yak meat that has passed hygiene and quarantine inspection. Priority should be given to lean meat from the hind leg or shoulder of the yak. ​​Remove fat, muscle membrane and bone fragments. The removal ratio should be ≥95% to ensure the purity of the meat. ② Seasoning preparation: Prepare seasonings that meet GB-2760 and industry standards according to taste requirements. The seasonings include 1%-2% salt, 2.5%-3.5% chili powder, 0.8%-1.2% chicken essence, 0.8%-1.2% white sugar, 0.4%-0.6% five-spice powder, 1.8%-2.2% roasted sesame seeds and 1.8%-2.2% peppercorns based on the weight of the yak meat strips. After the seasonings are sieved through an 80-mesh sieve to remove impurities, mix them evenly. Step (2) Rinsing: Rinse the trimmed yak meat with running water at 15-25℃ for 5-10 minutes, turning it over once every minute to remove impurities and blood. Step (3) Segmentation: Cut the yak meat into blanks with a thickness of 1cm, a width of 1cm, and a length of 5±0.1cm, following the direction of the yak muscle fibers; Step (4) Braising: Put fresh / chilled meat directly into a pressure cooker, add water to cover the meat by 2cm, add 10g ginger slices, 5g scallion whites and 20mL cooking wine per 1000g meat, cook at 0.1-0.15MPa pressure and 115-125℃ temperature for 15-25 minutes until the core temperature is ≥75℃, and cool to room temperature; Step (5) Cutting into strips: Cut along the muscle fibers into strips 5.0±0.2cm long × 1.0±0.2cm wide × 1.0±0.2cm high; Step (6) Drying / Stir-frying: Add 18%-22% of the weight of the yak meat strips to a wok with first-grade rapeseed oil. Add the meat strips to the cold oil at 25-30℃ and stir-fry over low heat at 120-150℃ until the surface turns brown. Add the prepared seasonings and stir-fry for 14-21 minutes until the moisture content is 9%-16% and there are no visible soluble seasonings. Turn off the heat and let it cool to room temperature. Step (7) Packaging: Vacuum or nitrogen-filled packaging with PA / PE composite film, each bag weighs 50-100g, vacuum degree -0.08 to -0.1MPa, heat seal 180-200℃ for 2-4 seconds; Step (8) Sterilization: Sterilize with high-temperature steam at 118-123℃ for 25-35 minutes or with 5-7kGy irradiation, and then cool to below 40℃; Step (9) Inspection: Test the appearance, taste, moisture, microorganisms and nutritional indicators. If it passes the test, it is a finished product.

2. The method according to claim 1, wherein the method is characterized by: In step (1)①, the yak meat selected has a fat content of ≤5%, and the fat content after trimming is ≤3%.

3. The method according to claim 1, wherein the method is characterized by: In step (4), the frozen yak meat needs to be thawed in advance at 4℃ for 12-24 hours. After thawing, the core temperature should be ≤5℃ before braising.

4. The method according to claim 1, wherein the method is characterized by: In step (6), the chili powder is 80 mesh facing-heaven chili powder, the roasted sesame seeds are 40 mesh white sesame seeds, and the peppercorns are a 1:1 mixture of red peppercorns and green peppercorns.

5. The method according to claim 1, wherein the method is characterized by: In step (6), a stainless steel wok with a diameter of 70-90cm and a depth of 25-35cm is used for stir-frying. An infrared thermometer monitors the temperature in real time, and the temperature difference is ≤5℃.

6. The method according to claim 1, wherein the method is characterized by: The PA / PE composite film thickness in the step (7) is 0.08-0.12 mm, the oxygen permeability is ≤5 cm3 / (m2·24h·0.1MPa), and the water vapor permeability is ≤2 g / (m2·24h).

7. The method according to claim 1, wherein the method is characterized by: In the step (8), the high-temperature steam sterilization is cooled by spraying, and the cooling time is 10-15 minutes.

8. The method according to claim 1, wherein the method is characterized by: In the step (2), the flowing water flow rate is 0.4-0.6 m / s, and after flushing, the meat surface is free of blood water residue, and the water transparency has no obvious change.

9. The method according to claim 1, wherein the method is characterized by: In the step (5), the sterile slitting machine is used for slitting, and every 100 slits are checked by vernier caliper, and the size qualified rate is ≥98%.

10. The method according to claim 1, wherein the method is characterized by: In the step (9), the protein retention rate is ≥90%, and no harmful substances such as aldehydes and ketones are detected.

Images