Views: 0 Author: Site Editor Publish Time: 2022-09-24 Origin: Site
Xiaobian Mingwei analyzes the preservation measures of different foods in modified atmosphere packaging for you.
Walking into the market, we can always see modified atmosphere packaging of various foods, and soon the outer packaging is exquisite, and the effect of preservation is different. So how does the modified atmosphere packaging of different foods achieve the effect of preservation in the production process, and what kind of preservation measures are needed? Let's let Zhejiang Mingwei Xiaobian take you to understand the preservation methods of different foods in modified atmosphere packaging.
First of all, the preservation measures of different foods These different conditions mainly include different types of fresh-keeping gases, different mixing ratios of fresh-keeping gases, and fresh-keeping films with different barrier properties.
1. Preservation parameters of cooked food products: preservation of cooked food products such as livestock, poultry and aquatic products (salted duck, sauce duck, roast chicken, cooked beef, aquatic products, etc.), cooking, stewed vegetables, fast food, etc. The purpose of bacterial production is to maintain the original taste of food. The fresh-keeping gas is generally composed of nitrogen, carbon dioxide and other gases. After these foods are packaged with modified atmosphere, the fresh-keeping gas forms a protective film on the surface of the food, thereby achieving the purpose of inhibiting the growth and reproduction of microorganisms such as bacteria, and maintaining the nutrients and original taste of the food. When the ambient temperature is 20 degrees Celsius, the fresh-keeping period of the cooked food products packaged with composite gas is 10-20 days; at the refrigerated temperature (0-5 degrees Celsius), the fresh-keeping period is 60-90 days. Such foods need to use high barrier film packaging.
2. Preservation parameters of fresh livestock and poultry food: preservation of fresh pork, beef and mutton requires the purpose of antiseptic and ruddy color of fresh meat. Oxygen oxidizes myoglobin in livestock and poultry meat to oxymyoglobin, making the meat bright red. The use of oxygen-deficient packaging, such as vacuum packaging and nitrogen-filled packaging, will reduce the oxymyoglobin in the meat to myoglobin, and the meat will be lavender, which will be mistaken by consumers as not fresh and affect sales. The fresh pork, beef and mutton are packaged in modified atmosphere, and the fresh-keeping gas is composed of carbon dioxide, oxygen and other gases. High concentration of oxygen can keep fresh meat bright red, and carbon dioxide can be used for antibacterial and antiseptic. In the environment of 0-4 degrees Celsius, the shelf life of such foods can reach 7-30 days. If the fresh livestock and poultry food uses carbon dioxide, nitrogen, oxygen, etc. as the fresh-keeping gas, the fresh-keeping period can reach more than 30 days. Fresh poultry meat should adopt the high barrier film packaging.
3. Preservation parameters of fresh aquatic seafood: fresh fish and other aquatic products are perishable foods with high moisture content. When stored at low temperature, anaerobic bacteria are one of the factors that promote the corruption of fresh aquatic products. When fresh aquatic products are spoiled, toxins that are harmful to human health will be produced. Generally speaking, the preservation gas is composed of gases such as carbon dioxide, nitrogen and oxygen. Since fatty oxidative rancidity is the main cause of spoilage, in the process of adopting modified atmosphere preservation for fatty fish, the preservation gas is composed of gases such as carbon dioxide and nitrogen. The fresh aquatic products using compound modified atmosphere preservation, in the environment of 0-4 degrees Celsius, according to the variety and freshness of the raw materials, the fresh-keeping period ranges from 15-30 days. The packaging bag should use a composite plastic film with high gas barrier properties to maintain the gas concentration in the half bag.
4. Preservation parameters of fresh fruit and vegetable mushrooms: After harvesting, fruits and vegetables are still undergoing metabolic activities: absorbing oxygen and expelling carbon dioxide. If the oxygen content in the packaging bag is reduced and the carbon dioxide content is increased, so that the fruits and vegetables maintain weak aerobic respiration without anaerobic respiration, the aging process of fresh fruits and vegetables can be delayed, the metabolic rate can be reduced, and the fresh-keeping period of fruits and vegetables can be prolonged. To keep fresh fruits and vegetables fresh by means of compound modified atmosphere, breathable plastic film should be used as the gas exchange film, and the gas in the packaging bag can be exchanged with the atmosphere: the oxygen in the atmosphere penetrates into the packaging bag, and the excess carbon dioxide in the packaging bag is discharged. into the air to maintain the weak respiration activity of fruits and vegetables. The fresh fruits and vegetables are packaged with modified atmosphere, and the fresh-keeping gas is composed of carbon dioxide, nitrogen and oxygen. The proportion of gas and the fresh-keeping period should be determined according to the characteristics and freshness of the fruit and vegetable varieties. Common fruits and vegetables such as strawberries, mushrooms, lychees, peaches, vegetables, etc., in the environment of 0-6 degrees Celsius, the fresh-keeping period is 20-60 days. The packaging bag should use a low-barrier film.
5. Preservation parameters of baked food: The deterioration of barbecued food is mainly manifested by mildew. The requirements for preservation are mildew prevention and preservation of flavor. The preservation gas is composed of carbon dioxide and nitrogen. If cakes (excluding cream cakes) and breads are kept fresh with modified atmosphere, the fresh-keeping period at room temperature is 30-60 days. The moon cakes adopting compound modified atmosphere preservation have a fresh-keeping period of 90-120 days at room temperature. The packaging bag should use a composite plastic film with high gas barrier properties to maintain the gas concentration in the packaging bag.
6. Preservation parameters of kimchi and pickled vegetables: Kimchi food is prone to oxidation and mildew in the air. Carbon dioxide and nitrogen should be used as the preservation gas, which can be preserved for 20-90 days at room temperature. We should adopt the high barrier film for packaging bags.