What is the cause of the presence of microorganisms in food?

Name: Microbial Food Subject Words or Keywords: Microorganisms Nucleic Acids Life Sciences Protein Content Microorganisms are entities of nucleic acids and proteins, most of which are single-celled, and the production of these single-celled microorganisms by fermentation can obtain extremely rich single-cell proteins.

Microorganisms reproduce at an astonishing rate, and a cow weighing 500 kilograms can only synthesize kilograms of protein per day. A 500-kilogram viable cell can produce 1,250 kilograms of single-cell protein in 24 hours under the right conditions. Proteins produced by single-celled microorganisms can be used to make foods such as artificial meat, artificial fish, and artificial flour.

Fermented food is a kind of food processed and manufactured by human beings skillfully using beneficial microorganisms, with unique flavors and enriching our dietary life, such as yogurt, cheese, wine, kimchi, soy sauce, vinegar, tempeh, milk curd, rice wine, beer, wine, and even stinky tofu and stinky winter melon, which are quite attractive and long-term favorite foods.

1. As long as the temperature is suitable, microorganisms will grow and multiply and decompose nutrients in food to meet their own needs. At this time, the protein in the food is destroyed, and the food will emit a foul and sour taste, lose its original toughness and elasticity, and the color will also change. 2. When microorganisms contaminate food and multiply on food in large quantities to pathogenic quantities or multiply to produce disease-causing toxins, people will experience food poisoning when they eat this food.

3. Food spoilage caused by the reproduction of microorganisms; Due to the action of oxygen in the air, it causes oxidation and deterioration of food ingredients; Due to the action of oxidase, peroxidase, amylase, protease, etc. contained in food, it promotes the metabolism of food, produces heat, water vapor and carbon dioxide, resulting in food deterioration; Due to the erosion and reproduction of insects and indirect and direct contamination of harmful substances, food spoilage. 4. Penicillium, Aspergillus, Mycobacterium tuberculosis, Vibrio cholerae, Staphylococcus aureus, Escherichia coli, Pneumococcus, Helicobacter pylori, Brachybacterium flavus, Corynebacterium glutamicum. There are dozens of common epidemics and infectious diseases transmitted by bacteria, such as tuberculosis, diphtheria, influenza, hay fever, meningitis, asthma, Legionnaires' disease, etc.

SARS and avian influenza are also airborne infections that pose a threat to humans. According to the World Health Organization (WHO), ; With a total of more than 700 m3 of bacteria in the air, the danger of contracting diseases is obvious.

1.First of all, the environment must be suitable for the growth of microorganisms, such as temperature, humidity, pH. 2.It's more, depending on whether it is edible, and how to use it.

1. There must be an environment where such microorganisms grow.

2. Some microbial infections are harmless The traditional hazard should refer to mildew.

1.Fermented foods.

Yogurt, fermented bean curd, etc., have a unique flavor and are easier to absorb. Wine, sauce, oil vinegar 2Antisepsis.

Inhibits the growth of harmful microorganisms through the reproduction of beneficial microorganisms.

3.Use the advantages of microorganisms to produce food additives or functional health products.

1. Biological contamination Biological contamination of food includes contamination by microorganisms, parasites, insects and viruses.

Microbial contamination mainly includes bacteria and bacterial toxins, molds and mycotoxins.

In addition to pathogenic bacteria that can cause food poisoning and zoonotic infectious diseases, bacteria that appear in food include non-pathogenic bacteria that can cause food spoilage and can be used as a sign of food contamination.

Parasites and eggs contaminate food indirectly or directly through water or soil, mainly through the feces of sick and sick animals.

Insect contamination mainly includes beetles, mites, and moths in food, as well as flies and maggots in animal food and fermented food.

Viral contamination mainly includes hepatitis virus, poliovirus and foot-and-mouth disease virus, and other viruses do not easily multiply on food.

2.Chemical Contamination Chemical contamination of food is a wide range of situations and complexities.

Mainly include: pollutants from production, life and environment, such as pesticides, veterinary drugs, toxic metals, polycyclic aromatic hydrocarbon compounds, N-nitroso compounds, heterocyclic amines, dioxins, trichloropropanol, etc.; Harmful substances dissolved into food when food containers, packaging materials, means of transportation, etc. come into contact with food; abuse of food additives; Substances produced in the process of food processing and storage, such as harmful alcohols and aldehydes in wine; Substances added in the process of adulteration and counterfeiting.

3.Physical pollution is mainly due to a variety of complex non-chemical debris, although some pollutants may not threaten the health of consumers, but seriously affect the sensory properties and nutritional value of food, food quality can not be guaranteed, mainly: pollutants from food production, storage, transportation and marketing, such as grass seeds mixed in during grain harvesting, debris in liquid food container pools, dust and flies in the process of food distribution and marketing; Food adulteration makes fake, such as sand and gravel mixed into grain, water injected into meat, and a large amount of sugar mixed into milk powder; Radioactive contamination of food mainly comes from the mining, smelting, production, application and accident of radioactive substances.

Hello, dear, I am happy to answer for you, the microorganisms that play an important role in the process of food spoilage are mainly bacteria, yeast and mold. Although food microorganisms vary greatly depending on the food itself and environmental factors, bacteria are often more dominant than yeast and mold in general. The microorganisms that break down proteins and spoil food are mainly bacteria, molds and yeasts, and most of them do this by secreting extracellular proteases.

Among the bacteria, Bacillus spp., Clostridium spp., Pseudomonas spp., Proteus spp., and Streptococcus spp. have strong ability to decompose proteins. Microorganisms that break down fats produce lipase, which hydrolyzes fats into glycerol and fatty acids. Generally speaking, aerobic bacteria with strong protein decomposition ability, and most of them can also decompose fat, and many species of bacteria such as Pseudomonasporia, Chromobacterium, Yellow Bacillus, Alcaligenes and Bacillus have the characteristics of decomposing fat, and there are more molds that can decompose fat than bacteria.