Chapter 13 ; 2 Heat Treatments . If adequately dried and properly stored, dehydrated foods are shelf stable (safe for storage at room temperature). Foods can be dried in the sun, in an oven or in a food dehydrator by using the right combination of warm temperatures, low humidity and air current. The slowing of microbial activity with decreased temperatures is the principal behind refrigeration and freezing preservation. Drying removes the water needed by bacteria, yeasts, and molds need to grow. Fun Fact. blasts, tunnel, fluidized bed, spiral, belt freezers. Drying also slows down the action of enzymes (naturally occurring substances which cause foods to ripen), but does not inactivate them. Sterilization Heat to kill all bacteria and other organisms. Title: Food Preservation 1 Food Preservation . Aspartame ... – A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 8aeb3-MzJjY Refrigeration - lt 40 F ; Freezing - 0 F ; 4 Lowering Water Activity . Drying of Food - authorSTREAM Presentation. Difference Between Drying/ Dehydration and Concentration. Food preservation by low temperature. Since the beginning of time people have used the sun and nature as a preservation technique for removing moisture. In drying, warm temperatures cause the … Dehydration has been used widely for this purpose since ancient times; the earliest known practice is 12,000 B.C. Drying of foods is a very effective method of avoiding spoilage of food, since micro-organisms cannot flourish in the absence of moisture. One of the oldest methods of food preservation is by drying, which reduces water activity sufficiently to prevent or delay microbial growth. The drying food preservation method is easy to do, very safe, and can be used for most types of foods (meats, fruits, and vegetables). INTRODUCTION: INTRODUCTION Drying is a method of food preservation that works by removing water from the food, which prevents the growth of microorganisms and decay. Indirect contact freezing, e.g. The use of cold air blasts or other low temperature gases coming in contact with the food, e.g. It was possible for our ancestors to store food by drying it under the sun. Food Preservation Methods: Drying Drying, arguably the oldest food preservation method , is a great way of preserving herbs, fruits, vegetables and meats . Blanching Heat to deactivate enzymes ; Pasteurization Heat to kill pathogenic bacteria ; Sterilization Heat to kill all bacteria and other organisms ; 3 Low Temperature . Certain chemicals like sodium benzoate and potassium metabisulphite may be used for preservation, but they should be used with great care as an excess of any of them may result in poisoning. Since the beginning of time people have used the sun and nature as a preservation technique for removing moisture. Water is traditionally removed through evaporation, although today electric food … Flavors Complement, magnify or modify the taste of aroma of a food. Food Preservation Methods: Drying Drying, arguably the oldest food preservation method , is a great way of preserving herbs, fruits, vegetables and meats . Sun drying is the most common method to preserve the foods in rural area whereas in industries mechanical drying is in practice.