A Fermentation Method to Dry and Convert Shochu Distillery By-product to a Source of Protein and Enzymes

Abstract

Shochu distillery by-product (SDBP) is usually dried before using as an ingredient of formula feed. But drying is costly and causes destruction of the nutrients. In the present study, a new technique for drying SDBP by the fermentation using Aspergillus Awamori was established. In a ventilated container with blender, 6ton of wheat bran, 70ton of SDBP and 4.9ton of used oil were successively mixed and fermented by Aspergillus Awamori (6kg) for 70 days at 40°C. At the end of the fermentation, a sample was taken to measure the nutrient contents and activities of enzymes. Crude protein content of the fermented product (30.1%) was almost twice that of wheat bran (17.7%). Fiber content of the fermented product (10.2%) was reduced to the half compared with SDBP (22.4%). Totally 65,958kg of water was evaporated during the fermentation which represents 99% of the total original moisture. Interestingly, 88% of the lipids and 58% of the fiber were consumed by the fermentation. More interestingly, crude protein loss was the lowest (25%) among all the nutrients. The cost of drying SDBP is much lower than that of the usual drying method using heat. It is also noteworthy that the fermentation product contains high activities of carbohydrases and protease which may help digestion in animals. In conclusion, the present fermentation method is an excellent low cost technique to dry SDBP and provide a high protein source of feed.

Keywords

• aspergillus awamori
• feed
• shochu distillery by-product