The Chemical Characteristics and In Vitro Degradability of Pineapple By-Products as Potential Feed for Ruminants

SIMPLE SUMMARY: Pineapple (Ananas comosus L.) fruit is mainly consumed fresh or after its transformation into juice, jam, candy, beverages, ice cream, powder, or wine. During processing, many leftovers are produced and released into the environment, contributing to pollution. This current study investigated the possible utilization of pineapple leftovers from two varieties (Smooth Cayenne and Sugarloaf) cultivated in West Africa. They were characterized individually (crown, bud end, peel, core, and pomace) regarding chemical composition, in vitro fermentation characteristics, and estimated metabolizable energy. As a result, the lipids and lignin content were at low levels and they would not negatively affect nutrient utilization in ruminants. However, the low dry matter and high sugar content in pineapples highlight preservation issues in their by-products. The core and pomace of pineapples showed low structural carbohydrate content, high in vitro degradability, and high volatile fatty acid production. This study suggests that pineapple by-products can be used in ruminant nutrition; the crown, bud end, and peel can be used as fiber sources, while core and pomace can be used as energy sources. In West Africa, these by-products could help farmers to supplement ruminants’ diet during dry seasons characterized by the scarcity of natural pasture which represent the main feedstuff for ruminant in this region. ABSTRACT: Pineapple fruit, which is cultivated in tropical and subtropical areas, is processed by the food industry, generating a large amount of waste. Using pineapple by-products in animal nutrition could reduce feeding costs and contribute to the containment of pollution. The chemical composition and the in vitro fermentation of five pineapple by-products (crown, bud end, peel, core, and pomace) from two West African pineapple varieties (Smooth Cayenne—SC and Sugarloaf—SL) were evaluated. Significant differences were observed between the varieties and by-products. The dry matter (DM) content was low and superimposable between varieties, averaging 17.7%. On a DM basis, pomace showed the highest protein content (SC 8.10% and SL 8.81%, p < 0.001), whereas the crown showed the highest (p < 0.001) NDF content (47.62% and 39.01% for SC and SL, respectively). Due the high sugar content, the core and pomace showed high in vitro organic matter degradability (SC: 85.09% and SL: 83.98%), estimated metabolizable energy (SC: 7.91 KJ/kg and SL: 7.66 KJ/kg), and volatile fatty acid production (96.86 mmol/g and 90.62 mmol/g). Based on chemical composition and in vitro digestibility results, this study suggests that pineapple by-products have the potential to be used in ruminants’ diets, considering the crown, bud end, and peel as fiber sources and the core and pomace as substitutes or supplements to concentrate feedstuffs. Further research should be conducted on the storability of these by-products through in vivo trials evaluating animals’ performances and the quality of their products.