Bioprocesso de produção de goma xantana utilizando soro de leite caprino.

Abstract

Whey is a byproduct generated from the precipitation of milk fats and casein during cheese production that is generally discarded directly in water sources, causing serious environmental problems. Because it has nutrients and due to the large amount that is produced in cheese processing, whey becomes very attractive and economically viable in fermentation processes, such as xanthan gum production. Xanthan gum is a high molecular weight natural biopolymer produced by aerobic fermentation of phytopathogenic bacteria of the genus Xanthomonas in environments containing carbon sources. Because of its unique rheological properties, xanthan gum has many applications in a variety of industries, such as food, pharmacology, cosmetics and petroleum. It is easily soluble in hot or cold water, with the ability to produce high viscosity and act as a thickener, stabilizer and when associated with other gums, promotes a smooth and creamy texture in liquid foods. The objective of this work was to produce xanthan gum using Xanthomonas campestris, code UFPEDA 585, using goat whey as substrate. In addition to characterize their physical, chemical and technological parameters. Commercial xanthan gum was used as standard in Infrared Absorption Spectroscopy to identify the presence of characteristic bands in the gum produced by the bioprocess, as well as in the Thermogravimetry that was used to evaluate the thermal profiles. The highest production of xanthan gum was observed when goat whey was used as an alternative medium in a 72-hour fermentation period (37.75 g / L). In the rheological analysis, despite presenting low viscosity, xanthan gum solutions obtained by strain Xanthomonas campestris, code UFPEDA 585 showed a pseudoplastic behavior. Comparison of the bands of the FTIR spectra of commercial xanthan gum with the goat whey produced gum showed great similarity to each other and the main bands characterizing the xanthan gum were ratified. The thermogravimetric curve of xanthan gum produced with alternative medium showed a thermal profile similar to the thermogravimetric curve of commercial xanthan gum. The results indicated that the alternative medium based on goat whey may be promising in the production of xanthan gum, becoming an alternative for the use of goat whey from cheese.