If I can conclude anything at this point about costs, it might be this: the differences in costs among the usual methods of freezing (air-blast bulk or package and plate) are likely to be minor. Decision on which method to use will probably be determined by other factors more important in the overall economic picture. If, however, we consider a radically different freezing method, such as use of cryogenic materials, cost differences become large and important. Other factors that may overrule freezing cost considerations must indeed be important, or unavoidable, or both.
Product Quality Requirements. The profit motive requires that the least costly method of doing a satisfactory job must be used. But what is satisfactory or best varies by products. Some are easy to freeze, because rate of heat removal is not critical. Other products lose much quality by slow freezing.
An example of the former might be sliced strawberries mixed with sugar. Many in the industry feel that a fast freeze is not even wanted. Apparently the main quality requirement is to avoid microbial growth. An example of a product suffering from slow freezing is tomatoes. The problem of freezing tomatoes is so great that so far they are not frozen commercially. Most other products lie between such extremes. Among the products subject to texture damage by excessively slow freezing are green beans, asparagus, melons, and whole strawberries. These have high moisture content and lack the physical structure to withstand freezing damage.
