The Invisible Culprit: Understanding Microbial Spoilage of Food
Food spoilage can be defined as a process or alteration that renders a product unfit for human ingestion. This complex ecological phenomenon results from the biochemical activity of microbial chemical processes, which the dominant environmental factors will ultimately determine. Effective monitoring of the chill chain throughout production, transportation, distribution, and storage in retail cabinets and private refrigerators is essential for ensuring the safety and quality of foods and beverages. Food decomposes due to multiple factors, including microbial attack, enzymatic digestion, chemical degradation, and physical damage.
The following physical changes can identify microbial food spoilage:
Change in appearance: The formation of liquids and cloudiness in the food define appearance differences.
Change in texture: Due to the accumulation of microbial cells and tissue degradation, a change in texture occurs, resulting in the formation of mucus and decay.
Color change: It is primarily caused by the decomposition of chlorophyll and mycelial growth.
Change in taste and odor: Due to the oxidation of nitrogenous compounds, sulfides, organic acids, etc., by microbial enzymes, the flavor and smell of the food will change.
The majority of food deterioration is caused by organisms such as bacteria, yeast, and mold. Food is an excellent growth medium because it contains proteins, carbohydrates, and lipids used by microorganisms residing in food. Typically, hydrolysis of proteins (putrefaction) by proteolytic microorganisms, unintended fermentation by saccharolytic microorganisms, and rancidity by lipolytic organisms are involved in the degradation of organic material. This article discusses the definition, causes, and mechanism of microbial food decomposition and the microorganisms involved.
Definition of Microbial Food Spoilage
When microorganisms proliferate and become active in food, they cause it to degrade or decompose. This procedure results in undesirable alterations that render the food unsafe for consumption. Microbial spoilage of food depends on the food’s physical and chemical properties, the varieties of microorganisms involved, and the storage conditions. Microbial spoilage of food is solely the physical state in which the food no longer meets the quality characteristics. Controlling microbial food deterioration requires refrigeration, lyophilization, and the addition of preservatives.
The Process of Microbial Food Spoilage
The stages of Microbial Spoilage of Food can be summarised as follows:
Microbes attack: As the food contains all the nutrients microorganisms require at a favorable temperature, pH, moisture, oxygen, etc., microbes first attack the food.
Food degradation occurs when microorganisms use the nutrients in the food to decompose it.
Decomposition: Microbial enzymes conduct some chemical changes due to the enzymatic reaction between food components such as protein, lipid, fat, carbohydrates, etc.
Changes as a result of food decomposition As a consequence of spoilage, alterations in appearance, texture, color, flavor, and odor occur.
Causes of Microbial food spoilage
When bacteria, yeast, and molds grow on food products, they can spoil the food and make the food unfit to digest to the consumers. These microorganisms are naturally found in the environment and can contaminate food. The cause of such a process is related to several outside elements due to the type of product and how the product is packaged and stored. The conditions that support microbial growth and decomposition include temperature, pH level, water activity, oxygen concentration, and nutrients. Appropriate food handling and storage practices such as refrigeration and maintaining sanitation are essential to prevent microbial growth and spoilage.
Every year, one-third of the world’s food produced for human sustenance is lost due to spoilage. Bacteria and various fungi cause decomposition and can devastate consumers, but preventative measures are available.
Microorganisms Involved in Food Spoilage
There are typically three types of microorganisms responsible for food spoilage:
Yeasts: These are the type of fungi that are unicellular and are responsible for food fermentation. Low pH and low moisture are favorable conditions for the yeasts that cause food degradation. True yeasts and false yeasts are the two forms of yeasts. True yeasts transform sucrose into alcohol and carbon dioxide. False yeasts develop as a dry film on the surface of the food.
Mold: It is another type of multicellular fungi that generates a rigid, visible mass called mycelium on the surface of the food. Molds are aerobic organisms that require oxygen, slightly acidic conditions, water, and a temperature between 20 and 40 degrees Celsius to thrive. It primarily affects foods such as bread, dairy, and meat.
Bacteria: These are the organisms responsible for food spoilage under conditions of low moisture, warmth (5–60 degrees Celsius), neutral acidity, and oxygen.
Conclusion
Due to the development and activity of microscopic organisms on food, food deterioration can occur naturally, resulting in changes that make the food dangerous for human consumption. Bacteria, Yeast, and mold are responsible for this undesirable process. To keep food safe and prevent contaminated illness, it is crucial to properly handle and store food, such as refrigerating it and preserving proper hygiene. If we comprehend the microorganisms and mechanisms that lead to food deterioration, we can devise practical preservation and safety measures.
