[akstrohm]

Here are a few reviews on the subject that might help you out. I've just listed the citations and abstracts. You can look up the articles on your own and read the rest if you would like:

Lupien JR and Lin DX. 2004. Contemporary food technology and its impact on cuisine. Asia Pac J Clin Nutr. 13(2):156-61.

This article contains a general review of current food technologies and their effect on the quality and safety of foods. The uses of these technologies in the context of current and projected world population, urbanization prevention of food losses, preservation and trade of foods, domestically and internationally are briefly reviewed. Technologies discussed are related to food storage, refrigeration, frozen foods, milling and baking, canning, pickling, extrusion processes, fermentation, and to foods and food ingredients such as fruits and vegetables, animal products, fat and oils, canned products, and food additives.

Severi S, Bedogni G, Manzieri AM, Poli M, Battistini N. 1997. Effects of cooking and storage methods on the micronutrient content of foods. Eur J Cancer Prev. 6 Suppl 1:S21-24.

Food processing has the potential to alter the nutrient quality of foods. This review deals with the effects of home-based cooking and storage practices on the micronutrient content of foods. It describes the effects of cooking, freezing and refrigeration on the vitamin and mineral content of meats, fish, fruit, vegetables and cereals. Based on this review, we suggest that the consumer should be aware of the possibility that losses in nutritional quality of foods may result from an improper use of cooking and storage techniques available at home.