Can Dawul Kurundu (Neolitsea involucrate) leaf extract be used as a plant-based stabilizer in set yoghurt production?

The incorporation of plant-derived stabilizers in food processing and preservation has gained considerable industrial interest. The leaf extract of Neolitsea involucrate, Dawul Kurundu (DK), has proven to be a potent plant-derived stabilizing agent in the food industry. However, the potential of utilizing DK leaf extract in the dairy industry has not yet been proven. Thus, the feasibility of incorporating DK leaf extract in set yoghurt production by assessing its physicochemical, sensory, proximate composition, minerals (calcium and phosphorous), and microbial (Escherichia coli, yeast, and mold) quality parameters during storage at 4 degrees C up to 21 days was assessed. DK leaf aqueous extracts of 0.4% w/v (T2), 0.6% w/v (T3), and 0.8% w/v (T4) were used for testing with the control sample, 0.6% gelatin (T1). Compared to T1, there were no differences in color, taste, texture, and mouthfeel in all DK leaf extract-incorporated yoghurts, demonstrating the suitability of using DK leaf extract to replace the gelatin. A decreasing pattern of pH value was observed during 21 days of the storage period in all treatments, whereas total titratable acidity increased significantly with time. Furthermore, the lowest syneresis value was obtained by T4, demonstrating ideal stabilizing properties at higher incorporation levels. The proximate, mineral, and microbial compositions of all treatments showed no significant difference compared to the control. Therefore, overall results revealed that the 0.8% w/v level of DK leaf extract incorporation (T4) could be used as a potent stabilizer in set yoghurt production by allowing the possibility of replacing the gelatin without compromising its organoleptic properties. Improved and efficient methods for extracting the DK leaf extracts by focusing on their potential functional and health effects should be further examined.

Automated summary

The feasibility of incorporating DK leaf extract in set yoghurt production was assessed, and it was found that DK leaf extract can replace gelatin without compromising organoleptic properties. The study evaluated the physicochemical, sensory, proximate composition, minerals, and microbial quality parameters of DK leaf extract-incorporated yoghurts. The results showed that the 0.8% w/v level of DK leaf extract incorporation could be used as a potent stabilizer in set yoghurt production.