THE EFFECT OF PROCESSING VARIABLES ON THE QUALITY AND ACCEPTABILITY OF PISTACHIO MILK

ABSTRACT In an attempt to develop a new beverage from pistachio nuts, the effect of different methods of making paste, which involved grinding soaked kernels (method 1) and milling roasted kernels (method 2), as well as the blending time (20 or 30 min) and pH (6.5, 7.5 or 8.5) of the slurry on the pistachio milk compositions (protein, fat, total dry matter and total soluble solid), was evaluated. The taste and flavor of the pistachio milk were improved by the addition of sugar, vanillin and salt. The overall acceptability of the products was evaluated by 25 untrained panelists using hedonic test. The best processing conditions were milling the roasted kernels and blending the pistachio paste with water at pH 8.5 for 30 min. The most preferred flavor of pistachio milk is made by the addition of 5.0% sugar, 0.02% vanilla and 0.0% salt. PRACTICAL APPLICATIONS This study describes a process for preparing pistachio milk from small-sized and unsplit pistachio nuts that cannot be used for direct human consumption. This product can be served as a substitute for animal milk.