Faculty of Pharmacy, University of Tuzla and Faculty of Food Technology, University of J. J. Strossmayer Osijek
Abstract
The colour of peanut oil is pale-yellow, it has a neutral scent and it is rich in oleic and linoleic acid. The aim of this study was to investigate the effect of peanut kernel conditioning (25 °C, 35 °C, 45 °C, 55 °C), the addition of sunflower shells (3%, 6%, 9%), and the usage of oil during pressing. Peanut pressing is performed with a continuous press. Following the pressing process, a decision is made on the volume and the temperature of crude oil, as well as on pressing time. The additional steps include the natural precipitation of crude oil and the vacuum filtration of crude oil to obtain cold pressed oil. Some of the basic parameters for oil quality that are determined using standard methods are: peroxide number, free fatty acids, the proportion of insoluble impurities, and moisture content. Additionally, the results of the addition of natural and synthetic antioxidants on the oxidation stability of cold pressed peanut oil were examined. Finally, the results of the research show that conditioning and the addition of sunflower shells affect oil recovery during the pressing process. Conditioning peanuts at higher temperatures and the addition of a larger proportion of sunflower hulls resulted in greater amounts of produced oil. The natural antioxidant rosemary extract and synthetic propyl gallate achieve greater protection from oxidative degradation for the oil
