Assistant Laboratory Animal Technician (ALAT) Practice Exam

Which environmental conditions are likely to cause the most rapid breakdown of vitamin C in stored feed?

1. Cold and dry

2. Hot and humid

3. Cooled and sterilized

4. Room temperature and dark

The correct answer is: Hot and humid

Vitamin C, also known as ascorbic acid, is sensitive to environmental conditions, and its stability can be significantly affected by temperature and moisture levels. Hot and humid conditions are particularly detrimental for vitamin C breakdown because high temperatures can accelerate the chemical reactions that lead to its degradation. Additionally, humidity introduces moisture, which can facilitate the enzymatic and non-enzymatic reactions that break down vitamin C. In hot environments, the rate of oxidation increases, and this is compounded by the presence of moisture, which can lead to hydrolysis and other degradation pathways. Hence, stored feed exposed to both heat and humidity will experience the most rapid vitamin C degradation compared to other environmental conditions, making cold and dry settings far less harmful for vitamin C retention.