贵州省大米、玉米和辣椒中钙的生物可给性及其膳食营养价值评价

Bioaccessibility and dietary nutritional value assessment of calcium in rice,maize and chilli in Guizhou Province

目的对大米、玉米和辣椒中钙含量进行测定,探究钙的生物可给性差异及其膳食营养价值。方法采用分层随机抽样方法,样本来自贵州省的9个市州。基于火焰原子吸收光谱法测定大米、玉米和辣椒钙含量,通过体外消化模型(in vitro digestion model)模拟胃部及肠道消化,计算大米、玉米和辣椒中钙的生物可给性。结果辣椒钙含量最高,为(1799.50±398.70)mg/kg,其次为玉米,为(253.41±103.37)mg/kg,大米最低,为(69.90±20.53)mg/kg,3组钙含量差异有统计学意义(F=5249.93,P<0.001)。通过体外消化模型得出大米、玉米和辣椒在胃阶段钙的生物可给性均高于肠阶段(P<0.001);进一步分析发现,3者在胃阶段钙的生物可给性为大米(69.72%±10.31%)>玉米(41.40%±11.37%)>辣椒(35.31%±5.46%),差异有统计学意义(F=192.67,P<0.001);3者在在肠阶段钙的生物可给性为大米(56.69%±12.78%)>辣椒(23.29%±7.66%)>玉米(14.51%±5.19%),差异有统计学意义(F=294.73,P<0.001)。结论大米、玉米和辣椒中钙的膳食营养价值均有限,不是居民良好的膳食钙来源,因此,有必要开展相关的营养教育和干预,改善居民的饮食结构,增加牛奶和乳制品的摄入量,以减少膳食钙摄入量的不足。本研究可为我国居民建立合理饮食结构提供科学依据。

Objective To determine the calcium content in rice,maize and chilli,and investigate the differences in the bioaccessibility of calcium and its dietary nutritional value.Methods Stratified random sampling was used,and the samples were collected from 9 cities and prefectures in Guizhou Province.Calcium content of rice,maize and chilli were determined by flame atomic absorption spectrometry,the in vitro digestion model was used to simulate the digestion of the stomach and intestines to calculate the bioaccessibility of calcium in rice,maize and chilli.Results The calcium content of chilli was the highest of(1799.50±398.70)mg/kg,followed by maize of(253.41±103.37)mg/kg,and rice was the lowest of(69.90±20.53)mg/kg,the difference of calcium content between the 3 groups was statistically significant(F=5249.93,P<0.001).The in vitro digestion model showed that the bioaccessibility of calcium in the stomach stage of rice,maize and chilli was higher than that in the intestine stage(P<0.001).Further analysis revealed that calcium bioaccessibility in the gastric phase was rice(69.72%±10.31%)>maize(41.40%±11.37%)>chilli(35.31%±5.46%),with statistically significant differences(F=192.67,P<0.001);the bioaccessibility of calcium in the intestinal phase was rice(56.69%±12.78%)>chilli(23.29%±7.66%)>maize(14.51%±5.19%),with a statistically significant difference(F=294.73,P<0.001).Conclusion The dietary nutritional value of calcium in rice,maize and chilli is limited,and they are not good sources of dietary calcium for Chinese residents.Therefore,it is necessary to carry out relevant nutrition education and intervention to improve the dietary structure of residents and increase the intake of milk and dairy products,thereby reducing the insufficient dietary calcium intake.This study can provide a scientific basis for the establishment of a reasonable diet structure for Chinese residents.