Agiriga Anna Ngozi, Siwela Muthulisi
School of Agricultural, Earth and Environmental Sciences, University of KwaZulu-Natal, Pietermaritzburg 3201, South Africa.
Department of Food Science and Technology, Federal University Oye-Ekiti, Ekiti State 371010, Nigeria.
Prev Nutr Food Sci. 2018 Sep;23(3):235-244. doi: 10.3746/pnf.2018.23.3.235. Epub 2018 Sep 30.
Proximate, minerals, and anti-nutrient content of raw seed and seeds boiled and roasted for 10, 20, and 30 min, respectively were assessed. In addition, the effects of boiling and roasting for 10, 20, and 30 min on the antioxidant properties of seed extract were evaluated. Results showed that moisture, ash, fat, and crude protein were significantly reduced by boiling and roasting. Acid and neutral detergent fibres were significantly increased by roasting and boiling, with boiling causing a more significant increase than roasting. Processing resulted in significant decrease in magnesium, potassium, phosphorus, zinc, copper, manganese, and iron while calcium levels were unchanged. Total phenolics levels of raw seeds [(21.94 mg/100 g gallic acid equivalent (GAE)] showed a remarkable decrease (18.64 mg/100 g GAE) when the boiling time was increased to 30 min. Free fraction phenolics increased with thermal processing whereas bound phenolics decreased. Boiling was more effective in reducing anti-nutrients than roasting. Extracts of seeds possess significant 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis( 3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging properties in a concentration-dependent manner, and this was significantly reduced after thermal processing. seed extracts could be pharmaceutically exploited for antioxidant properties, and roasting may be preferred to retain the nutrient composition and antioxidant properties of seeds.
分别对生种子以及煮制和烤制10、20和30分钟的种子的近似成分、矿物质和抗营养成分进行了评估。此外,还评估了煮制和烤制10、20和30分钟对种子提取物抗氧化性能的影响。结果表明,煮制和烤制显著降低了水分、灰分、脂肪和粗蛋白含量。酸性和中性洗涤纤维含量在烤制和煮制后显著增加,且煮制导致的增加比烤制更显著。加工导致镁、钾、磷、锌、铜、锰和铁含量显著下降,而钙含量不变。生种子的总酚含量[(21.94毫克/100克没食子酸当量(GAE)]在煮制时间增加到30分钟时显著下降(18.64毫克/100克GAE)。游离酚类随着热处理而增加,而结合酚类则减少。煮制在降低抗营养成分方面比烤制更有效。种子提取物具有显著的1,1-二苯基-2-苦基肼和2,2'-偶氮双(3-乙基苯并噻唑啉-6-磺酸)自由基清除性能,且呈浓度依赖性,热处理后这种性能显著降低。种子提取物可因其抗氧化性能而用于制药,烤制可能更有利于保留种子的营养成分和抗氧化性能。