Food Preservation Chapter 13

Heat Treatments Blanching – Heat to deactivate enzymes Pasteurization – Heat to kill pathogenic bacteria Sterilization – Heat to kill all bacteria and other organisms

Refrigeration - < 40° F Freezing - 0° F Low Temperature Refrigeration - < 40° F Freezing - 0° F

Lowering Water Activity Dehydration Concentration Salt Addition of Sugar

Chemical Preservation

Food Additives Food additives are any substitute that becomes part of a food product either directly or indirectly during processing, storing or packaging.

Regulations on Food Additives The Food and Drug Administration 1938 Food Drug and Cosmetic Act 1958 and 1960 Amendments Delaney Clause

GRAS Generally Recognized As Safe First established 700 placed on the list without going through testing Now those substances are being reevaluated Foods have been removed

What It Takes to Become A Food Additive Prove additive is effective Prove additive can be detected and measured in final products Study the effects of the substance on animals (in large doses) Submit results to validate the findings Schedule a public hearing FDA approves or rejects

Functions of Food Additives 1. Preservatives – Keep food fresh and reduce spoilage. Control bacteria, mold, fungi, and yeast. Benzoates BHT, BHA (antioxidants) Calcium Propionate (inhibits molds) Sodium Bisulfate Sodium Nitrate

Functions of Food Additives 2. Processing Aids – Improve consistency, add stability, aid oil and water mixtures, and retain moisture Gums (Algin, Carrageenan, Xanthan) Aluminum Calcium Silicate Benzoyol Peroxide

Functions of Food Additives 3. Nutrients – Maintain or improve the nutritional quality of food. Alpha- tocopherol Ascorbic Acid Biotin Beta Carotene Calcium Pantothenate Folic Acid

Functions of Food Additives 4. Flavors – Complement, magnify or modify the taste of aroma of a food Aspartame Corn Syrup Ethyl Vanillin Mannitol Monosodium Glutamate

Functions of Food Additives 5. Colors –Give foods a desired, appetizing or characteristic color. Carmel Beta-apo-8-Carotenal (Orange) Citrus Red FD&C Blue No 1 FD&C Red No 3 FD&C Yellow No 5

Other Methods of Preservation

Controlled or Modified Atmosphere Storage and Packaging Modified Atmosphere (MA) Nitrogen CO2 Controlled Atmosphere (CA) Vacuum Packaging Shrink Wrapping

Pasteurization Sterilization Irradiation Pasteurization Sterilization

Irradiation kGy Food approved in the US Pork Chicken Beef Fruits and Vegetables Grain Many other foods approved in other countries

Irradiation Source -

Irradiated Beef Patties

Purpose To evaluate ordor, flavor, texture, and overall acceptability of irradiated ground beef patties stored over a six-week period

300-2.8 oz patties were blast frozen Packed 20 patties per Cryovac bag Vacuum sealed Placed in a corrugated box and packed in dry ice Irradiated in Florida Dosimeter placed inside boxes Stored at –18°C Sampled weekly for 6 weeks

Overall acceptability of irradiated ground beef patties 0 1 3 5 7 Dose (kGy) Weeks 0 6.3 5.9 6.5 6.8 6.0 1 6.6 6.7 6.3 6.2 6.2 2 6.0 6.3 6.0 6.3 6.6 3 6.4 6.3 6.2 6.1 6.2 4 6.6 6.3 5.7 6.2 5.8 5 6.4 5.9 5.5 5.9 5.3 6 5.7 6.2 5.4 6.0 5.1 1 (=dislike 9 (=like)

Irradiated Strawberries

Materials and Methods Fruit were irradiated at doses of Stored for periods of 0, 1, 3, 5, and 7 days at 2oC

Results Ascorbic Acid

Results DHA

Irradiated Strawberries