Shelf life temperature change

The stability of excipients is almost always taken for granted. Obviously, there is the potential for a phase change with certain lower melting excipients, e.g., semisolid materials, however, this is not a chemical phenomenon although it may enhance the potential for interaction by increasing the effective interface available at which the interaction can take place. However, some materials are not stable under conditions encountered in excipient compatibility screening or accelerated stability testing. A notable example is dibasic calcium phosphate dihydrate. At temperatures as low as 37°C, under certain conditions, the dihydrate can dehydrate to form the anhydrous material with the concomitant loss of water of crystallization (25), and at 25°C, it is a stable solid with a shelf life, when stored correctly, of more than two years. 

Flavor changes that occur in citrus juices are the result of heat input into the product over time i.e., they are a function of temperature and time. It is for this reason that canned and bottled juices are generally less preferred by consumers than other processed citrus juices, e.g., frozen concentrates or chilled juices. The canned juices receive more heat input during pasteurization and they remain at relatively high temperatures for extended periods of time because they are discharged from the water coolers at temperatures near 40°C to facilitate drying and to inhibit rusting of the cans. It is well known that the rate of flavor deterioration increases with temperature, so canned juices are stored at a temperature as low as is economically practical before distribution at the retail level to extend their shelf life as much as possible. 

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