Valorization of by-products from the processing of Ananas comosus L. Merril: State of the art

Abstract

Processing pineapple industry produces huge amounts of waste, thus contributing to aggravate the environmental problem. With a view to preserving the environment from this waste, it is recycled into valuable finished products. The aim of this review is to make the current state of art on the physico-chemical composition and the use of pineapple waste in general and for the production of biogas and digestate. Pineapple residues are rich in sugar (82% total sugars, 55% reducing and 27% non-reducing), volatile compounds, phenolics and lignocellulosic matter. But being rich in these compounds in addition to potassium, they are low in mineral elements. Because the nutrients they contain, they are used as food products for livestock and are used in the production of chemicals (such as citric acid, xylitol, and vinegar), pharmaceuticals and cosmetics. Also, through anaerobic digestion, they produce large quantities of biogas that devoid of methane. On the other hand, co-digestion with other organic waste or harvest residues (pineapple leaves), the addition of soda (ash) and microbial consortia, the treatment of peelings by silage, with sulfuric acid (H₂SO₄) and alkaline hydrogen peroxide (H₂O₂) to optimize bio-methanogen production.