Browning during storage

Colorless oily liquid that is light and moisture sensitive. Becomes brown during storage due to liberation of iodine. 

I. Tosun and N. S. Ustun, Nonenzymic browning during storage of white hard grape pekmez (Zile pekmesi), Food Chem., 2003, 80, 441 143. 

O Beime, D. Effect of pH on nonenzymatic browning during storage in apple juice concentrate prepared from bramley s seedling apples, J. Food Sci., 51, 1073, 1986. 

Frozen apples are sliced and packed with dry sugar or in a sugar syrup. The major problem with frozen apples is the prevention of enzymatic browning during storage and especially after thawing. 

Figure 6. Predicted and experimental values of browning during storage at 4, 8, 20, 30, 40 and 50°C of orange juice with 6 ppm of dissolved oxygen.

Pale-yellow to dark-brown liquid with a faint odor like garlic. Odor becomes more pronounced during storage. This material is hazardous through inhalation, skin absorption (liquid), penetration through broken skin, and ingestion, and produces local skin/eye impacts. 

Various methods have been devised to prevent oxidation during storage. The most obvious is to store the LSD in nitrogen filled containers, but the excellent protection thus afforded is of course lost when the bottle or ampule is opened. Another method is to use an antioxidant Brown and Smith recommend ascorbic acid. A more sophisticated method, recommended on the highest authority, is to... 

Phenolic compounds are of interest due to their potential contribution to the taste (astrin-gency, bitterness, and sourness) and formation of off-flavor in foods, including tea, coffee, and various fruit juices, during storage. Their influence on the appearance of food products, such as haze formation and discoloration associated with browning in apple and grape products, is also significant. Furthermore, analysis of these phenolic compounds can permit taxonomic classification of the source of foods. The importance of each phenolic compound and its association with the quality of various foods is described further in Sec. IV, on food applications. 

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