In this post , we will enlist the various types of bacteria that can be found in different foods. We will discover their significance to your health and later discuss them comprehensively in subsequent posts.
Micro-organisms including bacteria, fungi, yeasts , and viruses contribute a considerable role in food safety both at household and industry level. Parasites, another type of micro-organism also lead to food poisoning incidences.
Beneficial micro-organisms include:
Not all micro-organisms per se are harmful, there are those that provide benefits when added to certain foods.
Essentially,the beneficial bacteria such as those found in food products such as yoghurt etc and moulds such as mucor have been used in the food industry since. These bacteria have aided in fermentation processes to allow for food preservation, and for medicinal purposes respectively.
However, the majority of micro-organisms are known to pose harmful health outcomes when they come in contact with food i.e. tehy cause food contamination and intoxication.
Food poisoning
Food-borne illnesses are caused by the intake of contaminated foods or water or the intake of foods that contain toxins from pathogenic micro-organisms e.g bacteria, viruses, fungi etc.
Food intoxication and food infection are both forms of food poisoning. A food infection is triggered by the increase of micro-organisms in the body. It occurs when you ingest a beverage or food substance with harmful micro-organisms(viruses,bacteria , fungi etc). It is also referred to as food-borne illness.It has a low infectious dose and longer incubation period even up to 72 hours. Common bacteria that trigger food infections include: Clostridium perfringens , Bacillus cereus etc.
Alternatively, food intoxication occurs when you consume a food substance or beverage that contains toxins produced by certain micro-organisms i.e. bacteria. It has a high infectious dose and shorter incubation period compared to a food infection.Common micro-organisms responsible for food intoxication include Clostridium botulinum, Staphylococcus aureua , mycotoxins etc.
Criterion of classifying bacteria
There are various methods used to classify bacteria including:
- The staining method-Gram positive and gram negative
- Based on cellular structures-spore-forming and non-spore forming bacteria i.e. spore-forming bacteria-examples include -bacillus , clostridium, the non-spore forming bacteria-examples include :species of lactobacillus, pediococcus, lactococcus,brucella, salmonella, campylobacter, streptococcus, leuconostoc, weisella e, capsulated bacteria , with flagella or without
- Based on growth requirements– temperatures i.e. psychrophiles found at temperatures below 18°C, thermophiles found at temperatures between 50°C-70°C and mesophiles found at about room temperatures between 10°C-40°C .
- Based on size and shape-spiral-shaped bateria i.e. spirula, rod -shaped bacteria i.e bacilli etc
Other micro-organisms include:
- Moulds e.g. aspergillus
- Viruses e.g norovirus, hepatitis
- Parasites-helminths, protozoa