Decomposition of supplementary vitamin C in diets compounded for laboratory animals.

Processing may result in losses approaching 20% of the added vitamin C. The extent of these losses depends upon the process and is apparently related to temperature and moisture. Storage losses are also related to processing conditions, and no more than 50% of the vitamin C present in the diet immediately after 6 weeks. These results indicate that the current practice of including 1000 mg/kg of vitamin C in pelleted guinea-pig diets should be satisfactory, provided such diets are used within 6 weeks of manufacture and are stored during this period in conditions conducive to stability, that is dry, not exposed to direct sunlight and, preferably, with an even cool temperature.