Transformation of vegetable waste of the food industry into value added products: the case of Cynara scolymus.

FISSORE E. N.; SANTO DOMINGO C.; URICARRIET, G.; ERHARDT, E.; ROJAS A.M. ; GERSCHENSON L. N.

Processed Foods: Quality, Safety Characteristics and Health Implications.

Nova Science Publishers, Inc.

Lugar: Hauppauge , NY ; Año: 2013; p. 83 - 106

Byproducts of vegetable food processing represent a major disposal problem for the industry. Transformation of vegetable waste of the food industry into value added products as fibres are, may contribute to diminish pollution and to recover valuable biomass and nutrients. A great number of diseases frequently occurring in developed countries such as various gastrointestinal disorders (hernia, duodenal ulcer, gall stones, Crohn?s disease, appendicitis, constipation, hemorrhoids, colon carcinoma), diabetes mellitus, obesity and cardiovascular diseases, have a lower incidence among people consuming high amounts of fibre. The benefits of the intake of fibres for the gut are amply recognized, fact that has determined its consideration as a nutrient. Fibre addition to foods is an alternative to compensate for the existent deficiency in the diet. Besides the nutritional aspect, fibres can be used for technological purposes because they can change food consistency, texture, rheological behavior and sensory characteristics. As only the tender inner bracts and the receptacle of the immature flowers of globe artichoke (Cynara scolymus L.) are used for consumption, residues can be upgraded to add value to its production, for example through their use for dietary fibre isolation. In this research, it was evaluated a procedure for the obtention of fractions enriched in soluble fibre from artichoke stems. These tissues were dehydrated (80°C2.5 h), milled, and dispersed in citrate buffer. Afterwards, cellulase was added and suspensions were incubated (30°C20 h). Procedures were repeated but without enzyme. Soluble fibre fractions were precipitated with ethanol, filtrated, washed and freeze-dried. Yields obtained were 5% in the absence of enzymes and 7% when cellulase was used. Fractions obtained were completely characterized observing a 69-70% (w/w) content of carbohydrates and a 25-28% (w/w) content of proteins. Carbohydrates included uronic acid and inulin. The use of the enzyme not only produced a yield increase but also an increase in uronic acid content. Both fractions helped to stabilize oil-in-water emulsions probably due to their high protein content. The flow behavior of aqueous solutions of both fractions was pseudoplastic. The use of cellulase for fraction obtention, determined a lower consistency index and the existence of a minimum shear stress. Procedure proposed allowed to isolate fractions enriched in soluble fibre, adding value to left over of Cynara scolymus industrialization, helping in the development of green processes for the agrifood chain and providing natural ingredients for more healthy foods.