- Jun 29, 2018 -
1. We first analyze the "expanding bag" phenomenon. Food that can "bulge" is definitely a sealed packaged food whose package pressure is less than or equal to the atmospheric pressure outside the package. "Expansion bag" indicates that the contents have undergone serious deterioration, and it also proves that the used bags have good sealing properties. If the packaging bag is not tightly closed or the surface of the bag is broken, the phenomenon of “deterioration” of the contents is normal, but the phenomenon of “bumping” will never occur.
2. We look for the cause of the "expansion bag". Most bacteria or molds that may cause food spoilage (Lactobacillus, Yeast, Oxygenobactobacillus, Bacillus polymyxa, Aspergillus, etc.) produce a lot of gas during the decomposition of protein and sugar in foods. Such as carbon dioxide, hydrogen sulfide, ammonia, alkane, etc., is the gas that blows the bag into a balloon. During the sterilizing process of the food before the packaging, the microorganisms and buds have not been completely killed. After the packaging is completed, the microorganisms multiply and corruption occurs, and the problem of swelling of the packaging bags naturally occurs.
3. What are the foods that are prone to "bulging"? In general, vacuum-packaged meat products are most likely to occur in the absence of preservatives, followed by liquid dairy products and high levels of animal and vegetable oils. Over the shelf life, or foods that need to be stored at cryogenic temperatures that are not stored at the required temperature, "expanding bags" may occur. If you find that a certain packaged food that has been in a normal temperature environment has exceeded the shelf life seriously and there is no point of corruption, the reason for this is self-evident. It is definitely that the preservatives are not added. As for why meat is relatively easy to "bump," First, because the vacuum packaging is the most stringent, the pressure inside the package is much lower than the external pressure, the external appearance of the gas after the expansion of the most apparent performance. Second, because of the high probability of contaminating spoilage bacteria in the processing of meat and dairy foods, and some meat foods are complex and heavy in structure, sterilization is not easy. For example, foods such as whole chicken roast duck are likely to have cavities inside. Causes microbial residue.