Food Safety for Farmer's Markets - Lectures

This series of lectures focus on food safety related to Farmer’s Market products and necessary controls for the microbiological hazards associated with these foods. Particular emphasis will be placed on low water activity foods such as baked goods and jellies, acid and low acid foods, and sanitation. A special presentation on mushrooms and mushroom safety will be included.

Intro to Microbiology

This lecture provides an overview of food microbiology. It starts by describing the different groups of microorganisms associated with food, such as molds, yeasts, and bacteria. It then focuses on bacterial reproduction, spore formation and the factors that affect bacterial growth and survival. The last part of this lecture focuses on bacterial pathogens associated with food, the disease they cause and processing factors that may be used to control them in foods.


This lecture describes the importance of sanitation in food retail and preparation environments and provides some basic knowledge in this area. Some of the topics discussed include proper cleaning prior to sanitation, chlorination basics, factors affecting the efficacy of chlorination, and some practices to prevent contamination and cross-contamination in the food preparation environment.

Water Activity

This lecture discusses the concept of water activity and how it is used to preserve foods such as baked goods, jams and jellies, honey and syrups.  Water is present in all foods and usually takes the form of free water, or water that is bound to different molecules. This lecture also describes how water activity affects the growth of bacteria, yeast and mold, which can affect the safety and quality of foods.

Acidified Foods

This lecture discusses the principles of acidified foods. In general, it covers definitions, regulations, and exemptions related to acidified foods, pH and acidity in foods, acidification procedures, thermal processing for acidified foods, and some processing considerations.

Low Acid Foods

Low acid foods that are high in moisture require special processing to render them shelf stable. In this lecture you will find out what the FDA’s regulations are for processing commercially sterile food — such as canned foods. These processing conditions are applied to ensure the thermal inactivation of pathogenic bacteria, like Clostridium botulinum.

Mushroom Safety

Mushrooms have been eaten for centuries and are a well-known part of the human diet worldwide. But just how much do you know about them? This lecture will provide an overview of mushroom identification and their potential for toxicity, with particular emphasis on species present in Nebraska.

Supplemental Videos

Downloadable Cards and NebGuides

Acidified Foods CardAcidified Foods Card
PDF Icon (835K)
Fruit Jelies

Fruit Jellies NebGuide PDF Icon (631K)
Acidified Foods Guide

Acidified Foods
NebGuide PDF Icon (636K)
Selecting a pH Meter Guide

Selecting a pH Meter NebGuide PDF Icon(629K)

For video lab demonstrations please visit the

Science of Safe of Food - Food Safety for Famer's Markets Lab page.

Questions? Please contact the Food Processing Center at