Coffee (Coffea Arabica) Waste Management by Increasing the Quality of Its Crude Protein and Crude Fiber Content by Fermenting Using Rhizopus Oryzae and Saccharomyces Cerevisiae as Animal Feeds

Abstract

Recently, coffee is the most significant food commodity worldwide which coffee husk and pulp are its main by-products. Proposed alternate uses for coffee husks include employing this solid residue as a supplement for animal feed, direct use as fuel and fermentation for the production of a diversity of products (enzymes, citric acid and flavoring substances), use as a substrate for growth of mushrooms and use as adsorbents. Coffee husks normally accumulate carbohydrates (carbon and nitrogen) as it presents a high concentration of carbohydrates and thus can be viewed also as a potential raw material for bio-ethanol production. However, coffee husks as animal feed are not palatable to cattle, and they can form only a small portion of rations fed to unproductive animals. Responding to these issues, this research was conducted to increase the quality of coffee (Coffea arabica) waste on its crude protein content and crude fiber content by fermenting coffee waste using Rhizopus oryzae and Saccharomyces cerevisiae in respect to inoculums dosage and fermentation time as animal feeds. The research used an experimental method with a nested completely randomized design (CRD). There were three dosages of Rhizopus oryzae and Saccharomyces cerevisiae (D1 = 0.2%; D2 = 0.3%; D3 = 0.4%), 3 fermentation times (T1 = 24 hours; T2 = 48 hours; T3 = 72 hours), and each treatment was repeated triplicate. Results were analyzed by analysis variant and Duncan's Multiple Range Test. The results showed that the coffee husks fermentation with inoculums significantly affected on crude protein and crude fiber contents. Application of 0.3% dosage inoculums for 48 hours resulted in 16.99% of crude protein content (which is higher than previous research, 8–11%) and 16.28% of crude fiber content.