Views: 0 Author: Site Editor Publish Time: 2022-11-04 Origin: Site
The difference between modified atmosphere preservation and quality preservation
When people buy food, they are accustomed to pay attention to the shelf life. The shelf life actually guarantees the safety of the food. However, with the improvement of people's living standards, it is not enough for people to only have safety requirements for food. They also hope that the food they eat is fresh. So the concept of "preservation" came into being. The so-called "preservation" means that on the basis of ensuring safety, the food can also be guaranteed in terms of nutrition, color, texture and flavor. The quality of the food can certainly be preserved, but the quality of the food may not be fresh.
The principle of composite MAP packaging preservation
1. Composite modified atmosphere fresh-keeping packaging is also known as gas replacement packaging, and is internationally known as MAP packaging (ie Modified Atmosphere Packing). The principle of the composite modified atmosphere packaging machine is to use composite fresh-keeping gas (2-4 kinds of gases are mixed according to the characteristics of the food) to replace the air in the packaging box or packaging bag, change the external environment of the food in the box (bag), and achieve inhibition The growth and reproduction of bacteria (microorganisms) slow down the metabolism of fresh fruits and vegetables, thereby extending the shelf life or shelf life of food.
2. Modified atmosphere preservation gas is generally composed of carbon dioxide (CO2), nitrogen (N2), oxygen (O2) and a small amount of special gases. CO2 gas has the effect of inhibiting the growth and reproduction of most spoilage bacteria and molds, and is the main antibacterial component in the protective gas; O2 gas can inhibit the growth and reproduction of most anaerobic spoilage bacteria, maintain the color of fresh meat and maintain aerobic respiration of fresh fruits and vegetables. The role of freshness; N2 is an inert gas, which does not work with food. As a filling gas, it forms a composite fresh-keeping gas with CO2, O2 and special gases. Different foods, fruits and vegetables have different components and proportions of fresh-keeping gas.
3. The technical key to the preservation of composite MAP packaging is the proportional control accuracy and gas replacement rate of the composite preservation gas. Due to the different performance characteristics of food fruits and vegetables themselves, the proportion of fresh-keeping gas is also different, and a considerable part of food, fruits and vegetables have considerable sensitivity to the proportion of fresh-keeping gas. For example, for the modified atmosphere preservation of lychee, the composition and proportion of the fresh-keeping gas required are: O2-5~7%, CO2-3~5%, N2-88~92%. If the gas mixing ratio of the modified atmosphere packaging machine cannot reach the corresponding If the accuracy is high, anaerobic respiration or CO2 damage will occur, and its preservation effect will be greatly affected. When the gas mixing accuracy error is greater than or equal to 3%, the fresh-keeping effect of lychee is worse than that of ordinary sealed packaging. Therefore, to judge whether the modified atmosphere packaging machine is qualified or not, in addition to the stability and reliability of the equipment, the gas proportional control accuracy and gas replacement rate should be used as the inspection standards. Therefore, a qualified composite modified atmosphere packaging machine must meet the requirements of the above two core technical indicators, otherwise the equipment must be a "pseudo composite modified atmosphere packaging machine", if you buy this type of product, it will definitely bring economic losses to the buyer.
The advantages of compound modified atmosphere preservation over other preservation (quality preservation) methods
At present, the commonly used food preservation (or quality preservation) methods are mainly: (1) chemical preservation; (2) freezing preservation; (3) vacuuming and high temperature sterilization for preservation; (4) vacuuming and nitrogen filling for preservation; (5) compound gas Adjustment and preservation; (6) Natural biological preservation. Among the above-mentioned six preservation (quality preservation) technologies, chemical preservation is the use of chemical agents to prevent and inhibit bacteria, but consumers are limited by the side effects of preservatives; the shortcoming of frozen preservation is that the taste of food changes after freezing; The disadvantage of bacteria is that it will greatly damage the unique taste, taste and nutrition of food; nitrogen-filled packaging can better maintain the taste, taste and nutrition of food, but it needs a sterile packaging environment, which has extremely high environmental requirements and requires a large amount of food. invest. Composite modified atmosphere fresh-keeping and natural biological fresh-keeping are brand-new fresh-keeping technologies developed on the basis of the above-mentioned traditions. They have relatively low requirements on the packaging environment and do not require large investment. They only need to sterilize the packaging environment with ultraviolet rays or ozone and sterilize the packaging environment. Corresponding specifications can be made for the soft environment. Its characteristic is that high temperature sterilization is not required. Therefore, compound modified atmosphere preservation can ensure the original food taste, taste and nutritional content, and truly guarantee the original juice, original taste and original appearance of the food.
Scope of use
(1) All kinds of stewed vegetables, stir-fried vegetables, fish and meat products; (2) Fresh livestock and poultry, aquatic products; (3) Fresh fruits and vegetables, mushrooms; (4) Moon cakes, cakes, bean products; (5) Pickles, pickled wax products; (6) Tea, Chinese herbal medicine and native products; (7) All kinds of food that need to be kept fresh in the supermarket distribution center.