Food Preservation Workshop July 11, 2009 Pat Sleiter & Tammy Schulte, Extension Master Food Preservers Bridget Mouchon, Extension Family Living Agent

Today’s Topics Why Preserve Food? Basic guidelines for food preservation. Resources available to help home food preservers, like you and me.

Why preserve foods? Increase the shelf life of food. Convenience Nutritional value Improve taste Feel good about it coming from locally grown produce or home garden Save money on food IT’S FUN!!

Canning, Freezing, & Drying OUR AIM: Safe, high quality foods.

Fight Food Spoilage Prevent mold, yeast, and bacteria from growing on your food. Prevent bruising and wilting. Prevent changes in flavor and texture, to the best of our ability.

Microbial Spoilage: Factors under our control! Food (provides nutrients microbes need) Acidity (microbes like low-acid, near neutral pH environments) Time (microbes need time to grow; we can heat foods to kill bacteria for the correct length of time) Temperature (Microbes like °F) Oxygen (Most microbes like oxygen and can’t live without it; however, the bacteria that causes Botulism only lives in the absence of oxygen) Moisture (Microbes like to be moist, need water to live)

Controlling Microbes Drying/salting/sugaring: ◦ All of these make water unavailable or less available to microbes. ◦ Salt and sugar both bind water and make it unavailable or less available to the microbes Acidifying: ◦ Adding acids such as vinegar or citric acid can create an unpleasant environment for microbes and extend shelf life.

Controlling Microbes: Freezing While refrigeration at 33-40°F slows the growth of microbes, and makes foods last longer freezing stops their growth altogether Deep quick freezes help keep cell structure of meats and vegetables intact and maintains better food texture and flavor. Blanching of some kinds of vegetables and sugaring of fruits also helps with this.

Controlling Microbes: Canning Canning combines multiple techniques, depending on the food and the recipe. Removes oxygen and seals jars. High heat kills microbes.

Canning continued: Preventing botulism poisoning Clostridium botulinum spores grow in the soil and are present in fruits and vegetables. These spores can only come alive in anaerobic or oxygen-free environments (i.e. inside a sealed jar) Once alive, the spores produce the deadly toxin which causes botulism poisoning 2 methods to ensure safety: If using hot water bath, must can a high acid product, like pickles, fruit, and salsa. Otherwise, must use pressure canner (240°F +)

Temperatures for Food Preservation: Applying Heat 240 to 250°F Canning temperatures for low acid vegetables, meat, and poultry in a pressure canner. 212°F Temperature water boils at sea level. Canning temperature for acid fruits, tomatoes, pickles, and jellied products in a boiling-water canner. 180 to 250°F Canning temperatures are used to destroy most bacteria, yeasts, and molds in acid foods. Time required to kill these decreases as temperatures increase. 140 to 165°F Warming temperatures prevent growth, but may allow survival of some microorganisms.

The Danger Zone 40 to 140°F DANGER ZONE. Temperatures between 40°F - 140°F allow rapid growth of bacteria, yeast, and molds.

Temperatures for Food Preservation: Keeping it Cool & Freezing 95°F Maximum storage temperature for canned foods. 50 to 70°F Best storage temperatures for canned and dried foods. 32°F Temperature water freezes. 32 to 40°F Cold temperatures permit slow growth of some bacteria, yeasts, and molds. -10 to 32°F Freezing temperatures stop growth of microorganisms, but may allow some to survive. 0 to -10°F Best storage temperatures for frozen foods.

Follow Instructions! When canning it is critical to FOLLOW INSTRUCTIONS and DO NOT ALTER RECIPES!! Use only recipes tested by USDA, The National Extension Service, or Ball Blue Book for absolute safety. Recipes from friends, neighbors, and the internet may be unsafe.

Do Not Use the Following Methods Oven canning: Does not ensure precise temperatures needed for safety. Open kettle canning: The temperatures never reach the proper canning temps needed Do not Hot Water Bath can low-acid foods.

Pressure Canners vs. Pressure Cookers If you buy a pressure canner, that can also be used as a pressure cooker, that’s great! (Such as the Presto 16qt or 23qt) YOU CANNOT USE A PRESSURE COOKER AS A PRESSURE CANNER.