Biotechnological utilization of food manufacturing residues

During the last year considerable progress has been made in the recovery and utilization of valuable constituents from food manufacturing wastes due to increased environmental awareness as well as economic motives. Selected biotechnological techniques in food waste management will be indicated with the aid of three examples: The utilization of lactose, sugar beet pulp and slaughterhouse blood. The utilization of whey is a classic example amongst the progress in utilization techniques. Beside the use of whey protein and whey powder as functional ingredients in the food industry whey be used as substrate for the production of lactic acid, L-ascorbic acid, butanol, xanthan gum or antibiotics. The conversion of sugar beet pulp to biogas can be combined with a two stage membrane separation process for the recovery of extracellular polysaccharide hydrolysing enzymes. An enzyme concentrate of pectinases, hemicellulases and cellulases can be from the fermentation broth. The use of slaughterhou se blood as a protein source is partly prevented by the dark red colour of the thick blood fraction which contains about 65 % of the total protein. After partial enzymatic hydrolysis of the haemoglobin the thick blood fraction can be separated into the dark red coloured iron containing haem and the globin protein solution. The flavour of the latter is affected by bitter peptides which might be avoided by the use of newly available aminopeptidases preparations.