Iodia Codina-Torrella
Universitat Autònoma de Barcelona
Spain
Title: Ultra-high pressure homogenization as a technology for the production of high quality tiger-nut beverages without stabilizing additives
Biography
Biography: Iodia Codina-Torrella
Abstract
These days, the interest of food industry for vegetal beverages has increased, between others, due to the milk allergy and/or intolerance in some people. Consequently, food industry focused on the development of vegetal beverages obtained from grains with a good nutritional value, which constitute a new generation of drinks. Tiger nuts are little sweet tubers widely cultivated in the different Mediterranean areas of the world, which are traditionally used for the beverage obtaining. These products are non-alcoholic milky drinks obtained from the aqueous extract of tiger nuts and water, characterized by their high content in carbohydrates and fat. High microbiological loads of these tubers make essential to hygienize this beverage in order to increase its short shelf-life, which make possible to place this drink in foreign markets. Furthermore, vegetal beverages require to be submitted to a homogenization process in order to improve the physical stability of the emulsion during their storage, as consumer request. Ultra-high pressure homogenization (UHPH) is an emerging technology based on the same principle as the conventional homogenization, but capable of working at pressures up to 400 MPa. This technology allows the microbial destruction and improves the colloidal stability of liquid products, maintaining their nutritional and sensory qualities, as well. Previous studies demonstrated that this technology could be an alternative process to those currently applied in the food industry (such as thermal pasteurization and sterilization processes). In line with this, the aim of the present work was to evaluate the UHPH as an effective technology for improving tiger-nuts shelf-life and their physicochemical stability, without added stabilizers, and maintaining the sensory characteristics of the untreated beverage as well, even if comparing with the conventional homogenized-pasteurized thermal treatment. The obtained results demonstrated the improvement of tiger-nuts beverage shelf-live with UHPH treatments (of ~ 30 and 60 days for 200 and 300 MPa treatments, respectively, at Ti = 40ºC), in comparison to the untreated (~ 3 days) and thermal pasteurized product (~ 20 days). Both UHPH-treated beverages also showed better physical (better colloidal stability) and chemical (lesser lipid oxidation) and sensory characteristics, even if comparing with the thermal treated drink (with and without stabilizing additives). In conclusion, the UHPH was presented as an emerging process for obtaining a new generation of vegetal beverages with improved quality and extended shelf-life, without the necessity of adding stabilizing additives (clean label beverages).