Food-borne illnesses caused by bacterial pathogens have raised concern about the safety of food over the past few decades. As a result, testing for biological hazards in foods is increasing significantly as awareness of food-borne diseases from microbial pathogens and their toxins gains more public attention and a higher regulatory profile. In addition, with hazard analysis and critical control point (HACCP) systems in place in many food industries, risk-based food safety assessment has become mandatory. Although the food industry, regulators and consumers would favour a totally risk-free food supply, zero-risk is neither practical nor achievable. Development of methods for identifying health hazards and predicting food safety is of high priority.