NFSC 112 Lecture Notes - Lecture 12: Adsorption, Instant Coffee, Water Activity

• School: University of Maryland
• Department: Nutrition and Food Science
• Course: NFSC 112
• Professor: Qin Wang

Document Summary

Convenience: handling/storage (e. g. , nfdm, preparation (e. g. , instant coffee, frozen dinners) Foods are preserved to make them last longer and often preservation gives foods the avors/ colors. We expect: some preservation methods just inhibit microbe growth, some methods kill organisms, some methods inhibit chemical reactions in foods, some methods do all of the above. Food preservation may make a food safer or may just make it last longer. Means to control moisture content, and hence aw in food. Removal of moisture in food via controlled, arti cial means. Final moisture content in food usually between 1-5% Moisture diffusion from the heat from hot air. Nature of water: free vs. bound water. Potential reactions in foods: browning, nutrient destruction. Drying of liquid or slurry by creating intimate contact between the liquid and the drying media. Fast, ef cient, and less heat damage to product.