SPLITTING AND BREAKING OF PISTACHIO NUTS WITH STRIKING AND HEATING
The objective of this study was to investigate the effects of heating process and striking on splitting and breaking of pistachio nuts and obtaining their kernels without damage. For this purpose, heating process (350C) was applied to pistachio nuts. Heated nuts were dropped onto the rotating disk and then thrown to strike the wall of the container by centrifuge effect . Striking velocity was adjusted with a rotating disk that was driven by an electrical engine. Three different disk rotations (400, 500 and 600/min) with three different moisture contents of pistachios (6.5, 22.0 and 42.5%) were evaluated in the experiments. Results indicated that the highest splitting rate was obtained as 29.33% at 22.0% moisture content with 400 1/min disk velocity. The most healthy kernel percentage obtained from unsplit pistachio nuts was 25.76% at 6.5% moisture content with 500 1/min disk velocity. Additionally, the study results showed that only the heating process had no affect while heating and crushing combinations increased splitting and obtaining the kernels. PRACTICAL APPLICATIONS
Consumption of healthy foods is very important for human health. Kirmizi variety of pistachio nuts contains a high ratio of unsplit pistachio nuts after harvest. These pistachio nuts are either consumed as appetizers or used in the sweets sector after extracting the inner part (kernel). The economical value of unsplit pistachio nuts is very low. For this reason, pistachio nut processing plants try to split them or extract the inner part without causing any damage. Unsplit pistachio nuts are split by hand or by primitive hand tools, such as hammer or pliers, and then extracted. This method is not healthy. This study is one of the limited studies concerning automatic, quick and economic splitting and extraction of pistachio nuts. After handling problems like splitting and extracting the kernel of pistachio nuts, pistachio nut processing plants will achieve a healthy pistachio nut production. This study offers a new system for healthy pistachio nut production, with low initial cost, lower wages and in less time.
Document Type: Research Article
Affiliations: Pistachio Research InstituteGaziantep, Turkey
Publication date: 2008-06-01