In food safety testing, microbial results are often treated as absolute judgments either “pass” or “fail.” But in reality, interpreting microbiological data is far more complex. A single result does not always tell the full story, and reacting incorrectly can lead to unnecessary product rejection, financial losses, or worse missing a real contamination issue. For…
Food safety is a critical aspect of public health, especially in developing countries where foodborne illnesses remain a major concern. One of the key microorganisms associated with food poisoning is Bacillus cereus. This bacterium is widely distributed in the environment and can contaminate a variety of foods, particularly cereals, dairy products, and ready-to-eat meals. This…
Introduction Salmonella is one of the most important foodborne pathogens worldwide, commonly associated with contaminated food, water, and poor hygiene practices. Accurate identification of Salmonella in microbiology laboratories is essential for disease diagnosis, food safety monitoring, and public health control. While selective and differential media help in the initial isolation of Salmonella, confirmatory biochemical and…
Reviewed by: Darwin Benedict, BSc Microb, MPH, Co-Editor. March 10, 2026 Introduction Salmonella are Gram-negative bacteria belonging to the family Enterobacteriaceae. They are among the most important foodborne pathogens worldwide, causing illnesses such as gastroenteritis and typhoid fever. Foods commonly associated with Salmonella contamination include poultry, eggs, meat, dairy products, vegetables, and ready-to-eat foods. Because…
Introduction Shigella are Gram-negative, non-motile bacteria responsible for shigellosis, a severe intestinal infection characterized by diarrhea, fever, and stomach cramps. The disease spreads primarily through contaminated food, water, or poor hygiene practices. The ISO 21567 standard provides a horizontal method for the detection of Shigella species in food and animal feed, including milk and dairy…
Acceptable Total Plate Count (TPC) Limits in Milk, Water, and Other Food Products Food safety and public health rely heavily on understanding microbial quality in foods and water. Among the most fundamental indicators of hygiene and product safety is Total Plate Count (TPC) — a measure of the total number of viable bacteria present in…
Reviewed by: Darwin Benedict,BSc Biochem, MPH, Co-Editor. January 11, 2026 Introduction Coliform testing is one of the most widely used microbiological methods in food safety laboratories. Coliforms are a group of Gram-negative, rod-shaped bacteria commonly found in the environment, soil, water, and intestines of warm-blooded animals. While most coliforms do not cause disease themselves, their…
Introduction Pseudomonas species are Gram-negative, rod-shaped bacteria commonly found in water, soil, air, and food processing environments. Although many Pseudomonas species are not primary human pathogens, they are major spoilage organisms and important indicators of hygiene and cold-chain integrity, especially in refrigerated foods. ISO 11059:2009 provides a horizontal method for the detection and enumeration of…
Reviewed by: Darwin Benedict,BSc Microb, MPH, Co-Editor. January 11, 2026 Introduction Yeasts and molds are fungal microorganisms commonly found in food, beverages, and the environment. While some yeasts are beneficial in fermentation (e.g., baking, brewing), undesirable yeasts and molds can cause spoilage, off-flavors, and foodborne illnesses. Some molds produce mycotoxins, which pose serious health risks….
Reviewed by: Darwin Benedict,BSc Microb, MPH, Co-Editor. January 11, 2026 Introduction Listeria is a genus of Gram-positive bacteria, with Listeria monocytogenes being the most notable pathogen causing listeriosis — a serious foodborne illness. Listeriosis can be life-threatening, particularly for pregnant women, newborns, elderly individuals, and immunocompromised people. ISO 11290-2 — titled Microbiology of food and…
