Aspectos sensoriais, físico-químicos e funcionais de uma bebida fermentada com grãos de kefir enriquecida com geleia de amora-preta (Rubus sp.)

Abstract

The aim of the present study was to evaluate the sensorial, physicochemical and functional properties of a fermented milk beverage made from kefir grains enriched with blackberry jelly (Rubus sp.). The samples of fermented milk beverage with different concentrations of blackberry jelly: A (0%), B (10%), C (20%) and D (30%) were submitted to acceptability and purchase intention. The most accepted beverage was characterized as pH, titratable acidity, soluble solids, colour parameters, antioxidant activity and total phenolic compounds. It was observed that samples C and D obtained greater global acceptance and purchase intention. However, sample C was selected to be characterized in terms of physicochemical and functional properties because it presents lower jelly content and, consequently, lower sugar addition, fulfilling the concept of a healthier product. The results of pH (4.73 to 5.13), titratable acidity (0.48% to 0.67%) and soluble solids (6.42 to 12.17 Brix), indicated that the addition of 20% of blackberry jelly improved the physicochemical characteristics of the product. However, the increase in jelly and hence chroma a* was not accepted by consumers when evaluating the appearance and color attributes. There was a 30% increase in antioxidant activity and almost 3 times the amount of phenolic compounds from the elaborated beverage compared to traditional. It is concluded that the addition of 20% of blackberry jelly is a good strategy both to improve the acceptability of the fermented milk beverage with kefir grains as well to increase the functional properties, adding to the probiotic beverage a greater antioxidant potential.