THE USE OF BETA GLUCAN AS A TEXTURE AGENT IN NATURAL SKIM YOGHURT

β-glucans are polysaccharides of glucose monomers linked by either linear chains or multiply branched structures, depending on the origin source. They are found in cereals, yeast, mushrooms, seaweeds and some bacteria, being a valuable font of dietary fibers. Several heath and industrial benefits are described. The aim of this study was to evaluate the use of β-glucan as a texture agent in natural skim yoghurt. The β-glucan was extracted from Saccharomyces cereviseae fungus. The texture profile of four yoghurt formulations (full fat yoghurt – FFY, skimmed yoghurt – SY, skimmed yoghurt with 0.5% β-glucan – SY0.5BG and skimmed yoghurt with 1.0% β-glucan – SY1.0BG) were evaluatedby Brookfield-CT texture analyzer. The formulations were stored at 8º C being weekly measuredfor parameters such as the firmness, adhesiveness, cohesiveness and gummines. Non-parametric Kruskal-Wallis tests were applied to determine significant differences (p<0.05) using the Statistica 13.0 software.Skimyoghurt firmness (SY - 0.98b N) increased with the addition of yeast β-glucan (p<0.05) on day 1 (SY0.5BG – 1.24a N; SY1.0BG – 1.15a,bN). This was the sole difference observed between formulations in recently manufactured yoghurt.On average, adhesiviness was 0.20mJ, cohesiveness was 0.8, and gumminess was 0.75 N, on day 1. During cold storage, it was observed that firmness was maximum on day 14 (p<0.05) for the four formulations, but decreased after this peak. FFY and SY1.0BGpresented the same behavior for gumminess during cold storage, with lower levels on day 1, compared to 14 and 28 days of cold storage. It was possible to develop a skim yoghurt with similar texture parameters of a full fat yoghurt by adding β-glucan. In addition, the product presents a natural fiber with health benefits to consumers.