Prevention of Storage Aging in Dried Raw Blue Fox Skins

Abstract

Ninety dried raw blue fox skins having two different dietary backgrounds, saturated fat and fish fat feeding, were submitted to the following experimental treatments: dressing after pelting; control storage at 8 ddot]C or at -20 ddot]C; antioxidant diet, storage at 8 ddot]C or at -20 ddot]C; butylhydroxytoluene (BHT) drumming, storage at 8 ddot]C or at -20 ddot]C; nitrogen gas, storage at 20 ddot]C; and pickling, storage at 8 ddot]C. Each storage group contained five skins from both dietary groups. Storage duration for the dried raw skins was approximately one year, during which the changes in their fatty acid compositions were analysed. After the storage period the skins were dressed and the physical characteristics of the leathers were determined.

The dietary background of the animals had a significant influence on the fatty acid profiles of the dried raw skins, but it did not affect their fat peroxidation during storage. Moreover, freezing at a temperature of -20 ddot]C or the antioxidant treatments employed did not prevent lipid peroxidation in the skins. In the pickle-treated skins the changes in the fatty acid profiles were even more pronounced than in the other groups. The only skins in which the fatty acid composition stayed constant were those stored in nitrogen gas.

The dietary background affected the breaking load and the elongation at break of the leather. Based on the measured physical characteristic of elongation at break, the quality of the leather decreased when the skins were stored in circumstances involving oxygen. The storage period is recommended to be kept to a minimum time, and storage temperatures above ±0 ddot]C should be avoided, because of water condensation. The results also emphasize the importance of careful conservation and proper handling of the dried raw skins.