Freeze-drying economics

In the following ten years, the scientific and technical presumptions have been the subject of many studies, to produce freeze dried food economically for long-term storage. However, there have always been four questions to be answered ... 

The freeze drying of coffee extracts has been, and still is, the most frequent application of this process in the food industry. For economic reasons it is best to start with 40 % solid content in the extract. The final product is judged by the following criteria ... 

Oetjen, G. W. Die Entwicklung der Gefriertrocknung von Nahrungsmitteln. Forschungs-kreis der Ernahrungsindustrie e. V. Bonn, October 1962. 5] Oetjen, G. W. Economical aspects of industrial freeze-drying. Le Vide, No. 102, p. 531-540, 1962... 

Because products rich in desirable NPs command a high price, it becomes economic to build storage facilities that reduce NP loss and to invest in improved packaging—look at foil wrapped tea or vacumn wrapped coffee. Freeze drying, controlled atmosphere packaging and optimum harvesting also help deliver the best NP-rich products to the consumer. 

Moy and Speilmann (90) recently reported on the economic feasibility of vacuum puff freeze drying of tropical fruit juices and nectars. They considered the process economically feasible if production rates were 250,000 or 1,000,000kg of dried nectar base per year (two plant sizes) with an assumed level of 35% sucrose (wet weight basis) blended with the juice or puree before dehydration. One assumption made in their study was that a marketing share equivalent to 0.5% of the annual orange juice volume in the U.S. was attainable. 

Oetjen, G.W. Economical aspects of industrial freeze-drying. Le Vide No. 102, 531-540,1962... 

Although spray-drying is unusual in analytical chemistry, it is occasionally preferred to freeze-drying for sample conservation as it is faster and more economical — and also the only effective way of removing the liquid phase when the sample is fat-rich [115]. 

A freeze-dried product intended for vaccine production should maintain its activity for as long as possible, as this conditions its shelf-life. It could be interesting to seek the sealing atmosphere most appropriate for activity preservation. This atmosphere should be compatible with the utilization of fairly large amounts from economical and safety viewpoints. 

For safety, economical storage and shipping, a ai must be quickly irradiated or pasteurized after removal from the tree, then processed into either a powder (by the expensive method of freeze-drying) or a frozen pulp puree. Irradiation and/or pasteurization are required safety procedures to destroy microbes, but also diminish vitamins and other nutrients, which become further reduced by subsequent steps in processing. The reduction of natural a< ai nutrients is evident from the Nutrition Facts panel on many commercial juice products—in most cases showing few if any nutrients. 

Experience has shown that freeze drying results in qualitatively superior products when compared to other drying and preservation methods. Herbs such as basil, chervil, dill, parsley, garlic, marjoram, oregano, rosemary, sage, tarragon, thyme and watercress are especially suitable. Economical reasons can also play a role. Freeze-dried products are, in contrast to fresh produce, constantly available all year round at rather stable prices ]27],... 

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