ABSTRACT
The generation of by-products is inevitable in any industrial process, and could not be different during the process for beer elaboration. In fact, a large variety of by-products and residues are generated by the brewing industry, which include products derived from the raw materials used for fermentation as well as broken bottles, crushed cans, metal lids, plastics, and so on. Some of them, mainly those derived from the raw materials (namely, the spent grains, surplus yeast, and spent hops, generated from the barley malt, yeast, and hop, respectively), are obtained in large amounts and, considering that they are rich in sugars, proteins, and minerals, have great potential to be reused as raw materials for other industrial processes. However, the industrial applications for these three brewing by-products are still limited, and they are basically sold to farmers for use as cattle feed, or simply as a landll.
