Effect of storage conditions on nutritional value, oil content, and oil composition of sesame seeds

Abstract

The increase in global demand consumption of sesame seeds as a nutritious food source and the limited areas suitable for cultivation have made the world face the challenge of determining the optimal storage conditions for sesame seeds. In this study, sesame seeds were stored in three different temperature and humidity conditions: High Temperature (HT: 60 °C, 100% humidity), Room Temperature (RT: 20 °C, 70% humidity), and Refrigerator Temperature (FT: 4 °C, 30% humidity), compared to the control (20 °C, 3% humidity). The soluble sugar, vitamins and protein contents of the sesame seeds were determined following standard methods. Fatty acids were determined by gas chromatography-mass spectrometry (GC-MS). Oil yield 11.2% increased under the HT storage condition, but no significant change was observed under the other storage conditions. HT conditions caused the degradation of fatty acids, while RT and FT conditions maintained the structure of fatty acids. Vitamin C levels decreased in FT, RT and HT storage conditions 0.0622, 0.0496, 0.0118 mg/100 g and vitamin B12 levels decreased 11.73, 12.02, 10.79 μM/100 g, respectively. Vitamin B9 levels increased in FT, RT and HT storage conditions 299.3, 222.3, 216.8 μg/100 g, respectively and vitamin E decreased 135.3, 30.7 mg/100 g under HT and FT conditions compared to control, however, no changes were observed under RT conditions. Total soluble sugar content increased 157.7 mg/100 g in FT conditions while it decreased 73.56 mg/100 g in HT conditions. This study showed storage conditions affected the nutritional value and phytochemical properties of sesame seeds. High temperature and humidity adversely affect the oil quality, fatty acid structure, and vitamin and sugar content of sesame seeds. Sesame intake in human dietary affected by the cooking process, such as roasting in dressing bread and confectionery reduce fatty acids, vitamins, and sugars in seeds. It seems that RT and FT are the optimal conditions for preserving fatty acids with high nutritional value in sesame seeds, although the moisture is different. The findings are important in controlling and maintaining the nutritional value of sesame during storage.