Articles made of organic materials include biological objects and their products and articles containing biological components. They are susceptible to mildew and spoilage due to the infestation and contamination of moldy microorganisms under normal environmental conditions. The quality of the articles is impaired and their appearance is affected. Mildew and spoilage of the articles are referred to as mildew rot. The mildew of an item means that after the mold grows and reproduces on the item, mold that can be seen by the naked eye appears. The corruption of an article refers to the decomposition of nutrients in the article caused by bacteria, yeast, etc., causing the article to be rotted when it is attacked and destroyed. Anti-mold and rot packaging technology is to fully understand the nutritional characteristics and living habits of moldy rot microbes, and take appropriate measures to ensure that the packaged goods are under certain conditions that can inhibit the growth of mold and rot microbes and extend the quality of the packaged products. . 55 Inch Teaching Interactive Whiteboard The use of high-efficiency multimedia 55 inch Teaching Interactive Whiteboard in education will not only improve the teaching efficiency of the school, but also improve the teacher's ability to guide students correctly, and 55 inch teaching smart whiteboard can let teacher spend time in effective places instead of wasting ineffective things. The intelligent touch 55 inch teaching all-in-one machine gives teachers more room for expression. The 55 inchteaching smart digital board belongs to the teaching market, and the 55 inch teaching interactive smart board market has been growing rapidly since the end of 2015. 55 Inch Teaching Interactive Smart Board,55 Inch Teaching All-In-One Machine,55 Inch Teaching Smart Digital Board,55 Inch Teaching Smart Whiteboard Guangdong Zecheng Intelligent Technology Co., Ltd , https://www.zecheng-security.com
The first thing is that the article is infected with mold and rot microbes, which is one of the necessary conditions for the decay of the article. The second reason is that the article contains the nutrients required for the growth and reproduction of the moldy rot microbes. These nutrients can provide the culture medium (including carbon source, nitrogen source, water, inorganic salt, energy, etc.) required for the moldy rot microbes. The third is that there must be environmental conditions suitable for the growth and reproduction of moldy rot microbes, such as temperature, humidity, air, etc. This is an external factor of the rot of the article.
The mold and rot microbes and their nutritive characteristics in the process of production, packaging, transportation, and storage of articles, due to continuous contamination of the surrounding air, soil, water, and micro-organisms of the human or animal body, causes the articles to have a large variety of microorganisms. Because of the growth and reproduction of microorganisms that cause a great deal of fungal decay, we must have a comprehensive understanding of these moldy rot microbes.
First, the common mold and its harm (1) Mucor mucor appearance hairy, with the ability to break down protein, often found in fruits, jams, vegetables, cakes, dairy products, meat and other foods, can cause food spoilage corruption.
(2) Rhizopus oryzae is similar in morphology to mucor, which can convert starch into sugar and cause mildew in food and its products.
(3) Aspergillus spp. According to different strains, the mycelium can be black, brown, yellow, green, red and other colors. Aspergillus has the ability to degrade organic matter, causing many kinds of food to be rotted.
(4) Penicillium Penicillium can be cyan, grayish green or tan. Penicillium can grow on various foods and cause food spoilage. Some of these penicillium species produce antibiotics such as penicillin.
(5) Trichoderma viride can cause mildew in grains, fruits, vegetables, etc., and it can also rot wood, leather, and fiber materials.
(6) Mouldings of Pueraria cinerea can cause mildew in food and endanger textiles, leather, paper and rubber.
(7) Fusarium Fusarium can cause mildew in cereals and fruits, some of which can produce toxins.
(8) Branches of Myxomyces are distributed in the soil and air and often appear in frozen and decayed eggs.
Second, the chemical composition of mold cells There are many types of mold, small size, but they are all living, is composed of a single cell micro-organisms. Microbial cells are composed of various complex compounds containing carbon, hydrogen, oxygen, nitrogen, and various mineral elements. At present, it has been determined that the composition of mold cells is approximately:
Moisture. About 85%-95% of the microbial cells are the main components of microbial cells. The hydrolysis of microorganisms, proteins, carbohydrates and fats, ie, the various physiological activities of microorganisms, require the participation of water.
Dry matter. The dry matter content of microbial cells is not fixed, but changes with the age of the bacteria and living conditions, accounting for about 15% -5% of the cells, of which about 90% are organic matter. For example, proteins, nucleic acids, carbohydrates, lipids, vitamins, etc. Others are inorganic substances such as sulfur, phosphorus, potassium, calcium, magnesium, iron, sodium, and trace amounts of copper, zinc, manganese, boron, molybdenum, and the like.
Third, the nutritional characteristics of mold 1, mold nutrients and their role of nutrients have two effects on the bacteria: nutrients in the metabolism of the bacteria can provide the required energy; In addition, nutrients can be synthesized into bacteria The composition of the body itself.
The nutrients needed for growth and reproduction of various bacteria include:
The growth of water bacteria must have a proper amount of water because the nutrients needed by the bacteria must be dissolved in water before they can be absorbed and utilized by the bacteria. In addition, various biochemical reactions in cells also need to be performed in aqueous solution.
Any carbon source that can supply bacterial carbon nutrients is called a carbon source. It is also an important material that constitutes cells. Some organisms use carbon dioxide as a carbon source, while others supply organic carbon compounds (such as monosaccharides, disaccharides, organic acids, alcohols, and cellulose) from outside.
Nitrogen sources Nitrogenous substances that can be used by bacteria are collectively referred to as nitrogen sources. It is an important element that constitutes intracellular proteins and nucleic acids. The nitrogen source is derived from inorganic nitrogen-containing compounds such as N2, NH3, NO3-, and organic nitrogen-containing compounds such as proteins and amino acids.
The mineral elements required by the mineral element include two main elements (phosphorus, sulfur, potassium, magnesium, calcium, iron) and trace elements (copper, zinc, cobalt, manganese, and molybdenum). The required amount of the main elements is not much, too much less will affect the growth and development of the bacteria; trace element content is less, have a stimulating effect on the growth of the bacteria.
Growth factors Organic substances that promote the growth and development of bacteria are called growth factors. The growth factors of bacteria are mostly vitamins. There are currently more than 20 known growth factors and are mainly B-group water-soluble vitamins, such as thiamine (B1), riboflavin (B2), and pantothenic acid ( B5), niacin (pp), pyridoxine (B6) and the like.
2. The nutritional characteristics of mold The mold is a heterotrophic microorganism, ie, the energy source required by the bacteria can only be obtained from the decomposition process of the ready-made organic matter. For example, carbon sources are obtained from organic carbon-containing compounds such as starch, cellulose, monosaccharides, disaccharides, and organic acids; nitrogen is obtained from inorganic nitrogen-containing compounds such as ammonium nitrate, ammonium sulfate, or organic nitrogen-containing compounds such as proteins and amino acids. source. Monosaccharides and polysaccharides are good substances for molds to absorb carbon sources; fats can also be used as carbon sources for molds; organic acids are poor sources of carbon for molds. Proteins and their hydrolysates, nitrates and ammonium salts are the main nitrogen sources for moulds, and amino acids can double as a nitrogen or carbon source for moulds.
One of the conditions for the normal growth and reproduction of mold is the need to have a certain pH environment. The lowest PH value of mold growth is 1.5, and the highest is 7-11. The optimum PH value for mold growth is 3.8-6. At this time, plants, animals, and microorganisms produce the most catalytically-active proteins, and nutrients can be sustained by the bacteria. Absorb well.