不同产地‘清香’核桃营养成分分析与 品质综合评价Nutritional components analysis and comprehensive quality evaluation of Qingxiang walnut from different regions

旨在为‘清香’核桃产业发展提供理论依据和发展思路，对4个产地的‘清香’核桃的感官品质、核仁基本营养成分和油脂脂肪酸组成及含量、核仁抗氧化物质含量和抗氧化能力进行测定，并采用主成分分析对核桃品质进行综合评价。结果表明：4个产地中，甘肃成县‘清香’核桃感官品质最佳，脂肪含量达70.41%，油脂中不饱和脂肪酸和多不饱和脂肪酸含量分别为91.80%和7589%，ω-6多不饱和脂肪酸与ω-3多不饱和脂肪酸含量比值（6.59）最接近中国营养学会推荐的比值范围；陕西宜君县‘清香’核桃水分含量（3.90%）、可溶性糖含量（1.53%）最高，DPPH自由基清除能力（179.73 μmol/g）最强；山西闻喜县‘清香’核桃核壳色泽得分、总黄酮含量（0.13%）最高，ABTS自由基清除能力（135.18 μmol/g）最强；河北赞皇县‘清香’核桃蛋白质、碳水化合物、单宁和维生素E含量最高，分别为1577%、3.96%、0.713 g/100 g和1.45 mg/100 g，但其涩味最重。4个产地‘清香’核桃综合品质得分从高到低依次为甘肃成县、陕西宜君县、山西闻喜县、河北赞皇县。综上，不同产地‘清香’核桃在感官、营养品质等多项品质指标上存在差异，其中，甘肃成县‘清香’核桃在外观、口感、油脂脂肪酸组成以及不饱和脂肪酸组成方面表现最好，综合表现最佳。Aiming to provide theoretical basis and development ideas for the development of Qingxiang walnut industry, the fruit sensory quality, basic nutrient composition of kernel, fatty acid composition and content of oil, antioxidant substances content and antioxidant capacity of Qingxiang walnut kernel from four regions were determined, and the principal component analysis was conducted to provide a comprehensive evaluation of the quality of Qingxiang walnut from different regions. The results showed that the sensory quality of Qingxiang walnut in Chengxian County, Gansu was the best among the four regions, with fat content in oil of 70.41%, unsaturated fatty acid and polyunsaturated fatty acid content of 91.80% and 75.89%, respectively, and the ratio of ω-6 polyunsaturated fatty acid content to ω-3 polyunsaturated fatty acid content (6.59) was the closest to the range of ratio recommended by the Chinese Nutrition Society. The highest moisture content (3.90%), soluble sugar content (1.53%), and the strongest DPPH free radical scavenging ability(179.73 μmol/g) were found in Qingxiang walnut from Yijun County, Shaanxi, while the highest score for color of walnuts′ seed shells, content of total flavonoids (013%), and the strongest ABTS free radical scavenging ability (135.18 μmol/g) were found in Qingxiang walnut from Wenxi County, Shanxi. The Qingxiang walnut from Zanhuang County, Hebei, had the highest protein, carbohydrate, tannin and VE contents of 15.77%, 3.96%, 0.713 g/100 g and 145 mg/100 g, respectively, but their astringency was the heaviest. The comprehensive quality scores of the Qingxiang walnut from Chengxian County, Gansu was the highest, followed by Yijun County, Shaanxi, Wenxi County, Shanxi, and Zanhuang County, Hebei. In conclusion, the Qingxiang walnut from different regions differed in quality indexes such as sensory and nutritional qualities, among which, the Qingxiang walnut produced in Chengxian County, Gansu, shows the best performance in terms of appearance, taste, fatty acid composition and unsaturated fatty acid composition of oil, and has the best overall performance.