Department of Food Science and Technology, School of Agriculture, University of Venda, Private Bag X5050, Thohoyandou 0950, Limpopo Province, South Africa.
Department of Food Science and Technology, School of Agriculture, University of Venda, Private Bag X5050, Thohoyandou 0950, Limpopo Province, South Africa.
Food Res Int. 2018 Feb;104:100-109. doi: 10.1016/j.foodres.2017.09.063. Epub 2017 Sep 24.
Banana fruit (Musa spp) though rich in essential minerals, has also been implicated for the presence of phytochemicals which nonetheless beneficial, can also act as mineral inhibitors when in forms such as phenolic compounds, phytates and tannins. This study assayed the essential macro and trace minerals as well as phenolic compounds present in unripe banana flour (UBF) obtained from the pulp of four different cultivars. Unripe banana flour was processed by oven drying in a forced air oven dryer at 70°C upon pretreatment with ascorbic, citric and lactic acid. Organic acid pretreatment was done separately on each unripe banana cultivar at concentrations of 10, 15 and 20g/L. Phenolic compounds were profiled using liquid chromatography mass spectrometry electrospray ion (LC-MS-ESI) while essential minerals were determined using inductively coupled plasma atomic emission spectroscopy (ICP-AES) and mass spectroscopy (ICP-MS) respectively. Results of LC-MS-ESI assay of phenolics revealed the presence of flavonoids: epicatechin and myricetin 3-O-rhamnosyl-glucoside in varying concentrations in UBF. Essential mineral profile indicated that Zinc had the least occurrence of 3.55mg/kg (p<0.05), while potassium was the most abundant mineral at 14746.73mg/kg in UBF of all four banana cultivars. Correlation between phenolic compounds and essential minerals using Pearson's Correlation Coefficient test revealed weak and inverse association between flavonoids and most macro and trace minerals present in UBF samples. Organic acid pretreatment thus exhibited little effect on phenolics and essential minerals of UBF samples, though, inhibitory influence of phenolic compounds was recorded on essential minerals.
香蕉果实（Musa spp）虽然富含必需矿物质，但也含有植物化学物质，这些物质虽然有益，但在酚类化合物、植酸和单宁等形式下也可能作为矿物质抑制剂。本研究测定了未成熟香蕉粉（UBF）中存在的必需常量和微量元素以及酚类化合物。UBF 是通过在 70°C 的强制空气烘箱中对预处理用抗坏血酸、柠檬酸和乳酸进行烤箱干燥来加工的。有机酸预处理分别在每个未成熟香蕉品种上进行，浓度为 10、15 和 20g/L。酚类化合物采用液相色谱-质谱-电喷雾离子（LC-MS-ESI）进行分析，必需矿物质采用电感耦合等离子体原子发射光谱（ICP-AES）和质谱（ICP-MS）分别进行测定。LC-MS-ESI 测定酚类化合物的结果表明，UBF 中存在不同浓度的类黄酮：表儿茶素和杨梅素 3-O-鼠李糖苷。必需矿物质分析表明，锌的含量最低，为 3.55mg/kg（p<0.05），而钾是所有四个香蕉品种 UBF 中最丰富的矿物质，含量为 14746.73mg/kg。使用 Pearson 相关系数检验对酚类化合物和必需矿物质之间的相关性表明，黄酮类化合物与 UBF 样品中存在的大多数常量和微量元素之间存在弱且相反的关联。有机酸预处理对 UBF 样品中的酚类化合物和必需矿物质的影响很小，但酚类化合物对必需矿物质有抑制作用。
