Optimization of processing parameters for manufacture of flavored lassi from buffalo milk

Abstract:

Consider a 500 mL bottle of cardamom-saffron lassi at a Cairo retail shelf in July 2024: it is expected to hold consistent flavor and a smooth body for two weeks without ingredient separation or sour drift. Meeting that expectation requires processing parameters matched to the unique fat and casein profile of buffalo milk, which this research set out to optimise. A three-factor experiment with homogenisation pressure (1500, 2000, 2500 psi), sugar level (5, 7, 9 percent) and flavor type (cardamom, saffron, rose) was conducted at the Alexandria University of Agriculture, Alexandria, between June 2022 and February 2023. Buffalo milk was standardised to 4.5 percent fat, inoculated with a 2 percent lactic starter culture and fermented to pH 4.4. The curd was churned, homogenised in two stages, blended with sugar and flavor, and cold-stored at 5±1 °C for 21 days. Response surface analysis identified 2000 psi, 7 percent sugar and cardamom flavor as the optimum, with an overall acceptability score of 8.6 at day 0 holding above 7.4 through day 14. Droplet size dropped from 4.8 µm to 1.7 µm under optimum homogenisation, syneresis was held below 6.2 percent through day 14, and microbial counts stayed within Egyptian Standards ES 1623 limits. The optimised process gave a two-week shelf life against seven days for the un-homogenised control.