The Effect of Different Non-mechanical Treatments on Splitting Pistachio Nuts

One of the undesirable features in pistachio nuts (Pistacia vera L.) is the incidence of non-split nuts, which affects the price of the final product. In order to attain the kernel inside, the non-split nuts are mostly cracked mechanically. However, this practice may damage the kernel. Akbari variety of pistachio nut was selected to evaluate the influence of different non-mechanical treatments on splitting the nuts. Different treatments were applied by soaking the nuts in water at different temperatures (10, 100 °C) and roasting and heating by oven and microwave in different orders. The results indicated that soaking along with thermal treatment had a significant effect on the amount of splitting (P < 0.05), while no significant effect was observed in the methods in which the samples were not soaked. Furthermore, the temperature of the water applied for soaking and also thermal treatment medium led to significant differences in the final results. Additionally, the order of application of different treatments were analyzed and proved to be significantly effective (P < 0.05) on the splitting percentage of the nuts.