Hemp press cake flour (HPCF) is a by-product of hemp oil production rich in proteins, carbohydrates, minerals, vitamins, oleochemicals, and phytochemicals. The purpose of this study was to investigate how the addition of HPCF to bovine and ovine plain yoghurts at concentrations of 0%, 2%, 4%, 6%, 8%, and 10% could change the physicochemical, microbiological, and sensory properties of the yoghurts, focusing on the improvement of quality and antioxidant activity, and the issue of food by-products and their utilisation. The results showed that the addition of HPCF to yoghurts significantly affected their properties, including an increase in pH and decrease in titratable acidity, change in colour to darker, reddish or yellowish hue, and a rise in total polyphenols and antioxidant activity during storage. Yoghurts fortified with 4% and 6% HPCF exhibited the best sensory properties, thus maintaining viable starter counts in the yoghurts during the study period. There were no statistically significant differences between the control yoghurts and the samples with 4% added HPCF in terms of overall sensory score while maintaining viable starter counts during the seven-day storage. These results suggest that the addition of HPCF to yoghurts can improve product quality and create functional products and may have potential in sustainable food waste management.
Keywords: bovine milk; by-products; hemp press cake; ovine milk; yoghurt.