INFLUENCE OF CHIA POWDER IN LOW FAT STIRRED YOGURT

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-12-6 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 61, 761-768 pp, DOI: 10.5593/sgem2017/61/S25.099

ABSTRACT

The purpose of this study was to determine an optimal variant for producing skimmed stirred yoghurt with chia powder. Three variants of product with chia powder at levels of 0.3%, 0.5%, respectively 0.7% and two control samples have been manufactured. Chia was used due to its remarkable content in fibre, ω-3 and ω-6 fatty acids, polyphenols, which are essential compounds for a healthy human body. The physicalchemical parameters (acidity, pH, dry matter) and rheological properties of yogurts samples were determined during storage period. Also, the diacetyl content was determined by gas-liquid chromatography coupled with flame ionisation detector (GLCFID). The results showed that the addition of chia powder increased the dry matter and titratable acidity and decreased pH value. The diacetyl increased for all samples during the storage period. The rheological determinations showed that yogurt viscosity gradually increased during 14 days of storage at 4°C. By analysing the rheological parameters it was determined the thixotropic nature and Bingham pseudoplastic behaviour of stirred yogurts. The addition of 0.5 % chia powder can contribute to the skimmed yogurt manufacture with similar properties to those of a fermented milk product containing 1.5% fat. It could be concluded that chia powder can be used successfully as a fat substitute with effects on improving the nutritional value of the product.

Keywords: stirred yogurt, chia, diacetyl, viscosity