Fresh keeping technology and application of the ho

Fresh keeping technology and application of compound modified atmosphere fresh-keeping packaging machine

compound modified atmosphere fresh-keeping packaging machine is a brand-new food, fruit and vegetable fresh-keeping packaging equipment developed on the basis of vacuum packaging machine and nitrogen filling packaging machine. Its biggest feature is to solve the problem of large destruction of food taste after vacuum packaging and high-temperature sterilization, and the lack of large investment in nitrogen filled packaging requiring sterile packaging. The service life of compound modified atmosphere packaging can reach several 10 years, which can ensure the original taste and taste of food, and ensure the original flavor and appearance of food

first, the difference between fresh-keeping and quality assurance

people are used to paying attention to the shelf life when buying food, and quality assurance is a necessary condition for food safety. With the improvement of people's living standards, people's requirements for food not only pay attention to its safety, but also hope that the food they buy is fresh, so the concept of "fresh" came into being. The so-called "fresh keeping" means that food can still be sold under the premise of ensuring safety, and the export growth of China's extruder products will show a stable and progressive situation. Nutrition, color, taste and flavor can be guaranteed. Fresh food is original, original, fresh-keeping will be able to guarantee quality, quality may not be fresh-keeping

II. Preservation principle of composite modified atmosphere packaging (map)

1. Composite modified atmosphere packaging is also known as gas replacement packaging, which is internationally known as map packaging (i.e. modifiedatmospherepacking). The principle of the compound modified atmosphere packaging machine is to replace the air in the packaging box/bag with compound fresh-keeping gas (the gases are mixed according to the characteristics of food), change the external environment of the food in the box/bag, inhibit the growth and reproduction of bacteria (microorganisms), slow down the metabolism of fresh fruits and vegetables, and thus extend the fresh-keeping period or shelf life of food

2. the modified atmosphere fresh-keeping gas is generally composed of carbon dioxide (CO2), nitrogen (N2), oxygen (O2) and a small amount of special gases. CO2 gas can inhibit the growth and reproduction of most spoilage bacteria and molds, and is the main antibacterial component in fresh-keeping gas; O2 can inhibit the growth of most anaerobic bacteria, maintain the color of fresh meat, maintain the aerobic respiration of fresh fruits and vegetables, and maintain freshness; N2 is an inert gas, which has no effect on food. As a filling gas, it forms a composite fresh-keeping gas with CO2, O2 and special gases. The composition and proportion of fresh-keeping gas are also different for different foods, fruits and vegetables

III. technical key of composite map packaging for fresh-keeping

the technical key of composite modified atmosphere fresh-keeping packaging is the proportion control accuracy of composite fresh-keeping gas and gas replacement rate. Due to the different performance characteristics of food, fruits and vegetables, they are quite sensitive to the proportional characteristics of fresh-keeping gases. Therefore, a qualified modified atmosphere packaging machine should be equipped with a highly accurate automatic gas mixing system, with a proportion error of less than 2% and a gas replacement rate of more than 99.5%. Otherwise, its fresh-keeping effect will be greatly affected, and even the fresh-keeping effect of some products is worse than that of ordinary sealed packaging. Whether the equipment is qualified or not should be based on the above two parameters

IV. advantages of compound modified atmosphere fresh-keeping compared with other fresh-keeping (quality assurance) methods

advantages and disadvantages of fresh-keeping methods

chemical preservative fresh-keeping process is simple and has side effects; Small quantity, poor anticorrosion effect

long shelf life of frozen preservation, great changes in taste and taste

long shelf life of vacuum high-temperature sterilization. After high-temperature sterilization, great changes in taste, taste and appearance, and great damage to nutrients

nitrogen filled fresh-keeping can better maintain food taste,

taste and original nutrition. It has high environmental requirements, requires sterile packaging, and has a large investment cost

composite modified atmosphere fresh-keeping packaging and fresh-keeping are completed at the same time, which can better maintain the original juice, flavor and appearance of food, and has relatively low environmental requirements, so there is no need for large investment

qualified equipment has high requirements for gas replacement rate (≥ 99.5%) and gas mixing accuracy (error rate ≤ 2%), complex structure and high equipment cost

v. application of composite modified atmosphere fresh-keeping packaging

the scope of application of modified atmosphere fresh-keeping packaging: (1) all kinds of pickled vegetables, fried vegetables, fish products; (2) Fresh livestock, poultry and aquatic products; (3) Fresh fruit and vegetable mushrooms; (4) Moon cake, cake and bean products; (5) Pickle cured products; (6) Tea, Chinese herbal medicine and local products; (7) All kinds of food that need to be kept fresh in the supermarket distribution center

VI. how to choose and buy modified atmosphere fresh-keeping packaging machine

1. There must be a high-precision automatic gas mixing device, whose accuracy control requirements are accurate, the maximum error rate should be ≤ 2.0%, and the ideal state should be ≤ 1.0%

the key to compound modified atmosphere fresh-keeping is to use compound fresh-keeping gas with accurate proportion according to the characteristics of different foods, such as the fresh-keeping of broccoli, whose gas mixing ratio is o2:%; Co2:%, injury concentration is 5%; N2:%, if the O2 content is low, it will cause anaerobic respiration and necrosis, while the O2 or CO2 content is high, which can not inhibit the respiratory rate and affect the fresh-keeping period; When CO2 exceeds its injury concentration, it will accelerate the deterioration of broccoli. Therefore, the core technology of modified atmosphere fresh-keeping packaging machine is to have a high-precision automatic gas mixing device; Another core technology of the modified atmosphere fresh-keeping packaging machine is the gas replacement device with high replacement rate (the replacement rate is 95%-99.5%), because if the gas replacement is insufficient and there is too much air residue, it cannot meet the expected fresh-keeping requirements. Therefore, a qualified modified atmosphere packaging machine must meet the requirements of the above two core technical indicators, otherwise the equipment must be a "pseudo modified atmosphere packaging machine". If you buy this kind of product, it will inevitably bring economic losses to the buyer

2. The manufacturer of compound modified atmosphere fresh-keeping packaging machine must fully master the knowledge related to food fresh-keeping.

compound modified atmosphere fresh-keeping is a multi link and multi field technical synthesis. Therefore, the manufacturer of modified atmosphere fresh-keeping packaging machine must have rich and comprehensive research on the characteristics of food, fruits and vegetables, pretreatment process, food processing environment, equipment combination, packaging materials and operating procedures. If the manufacturer has no grasp of the characteristics of food, how can we talk about food preservation? As an emerging product, the modified atmosphere fresh-keeping packaging machine has just come out, and many of its technical knowledge are not clear to consumers. Therefore, in addition to purchasing qualified equipment, customers should also require the equipment manufacturer to provide a full set of technical support to ensure that customers' products achieve the fresh-keeping effect

3. It is necessary to have high-quality R & D manpower and scientific research team until the conditioning is qualified.

whether the company reflects the development potential of a country's industrial development level to a certain extent, and how to ensure the quality of products, all of which require high-quality R & D personnel and professional scientific research teams. Without these as backing, whether the quality of products is qualified and whether it can win the trust of consumers, There are certain doubts. Therefore, when purchasing products, we should not only look at the price and appearance of products, but also pay attention to the internal quality of products and the R & D ability of manufacturing enterprises

4. The rationality of the structure and quality reliability of the modified atmosphere fresh-keeping packaging machine are also one of the safety choices.

the modified atmosphere fresh-keeping packaging machine is mainly used for food fresh-keeping packaging, and the packaging environment and the number of flora of packaging materials have a great impact on food fresh-keeping, so it is necessary to use stainless steel and anti-corrosion materials. In addition, because the heat sealing film roll may take several days to be used up in the actual production process, it is easy to be contaminated by bacteria, so the heat sealing film placed in a closed environment is not conducive to the use of ultraviolet or ozone sterilization

in a word, before purchasing air conditioning equipment, it is necessary to observe and compare comprehensively in many ways to avoid losses caused by purchasing unqualified products by mistake

source: China Food Technology