Plant Bioactives Group, Post-Harvest & Agro-Processing Technologies, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Private Bag X5026, Stellenbosch 7599, South Africa; Department of Food Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
Department of Food Science, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
Food Chem. 2019 Mar 15;276:626-635. doi: 10.1016/j.foodchem.2018.10.030. Epub 2018 Oct 6.
The bitter taste of Cyclopia genistoides infusions is unacceptable to consumers, who are used to the slightly sweet taste of the herbal teas produced from other Cyclopia species. Bitter taste intensities of crude phenolic fractions of a bitter hot water extract of C. genistoides were determined by a trained panel to identify the fraction contributing most to the bitter taste. Fractions, enriched in benzophenones (B), xanthones (X) and flavanones (F), and each tested at their infusion equivalent concentration (IEC) scored 5, 31 and 13 (on a 100-point scale), respectively. Fraction B, containing mostly iriflophenone glucosides, was perceived as not bitter. The major xanthone in fraction X, mangiferin, was significantly (p < 0.05) more bitter than its regio-isomer, isomangiferin, at equal concentration. A mixture of isomangiferin and mangiferin at their IECs was significantly (p < 0.05) less bitter than the mangiferin solution alone, indicating bitter suppression by isomangiferin.
消费者无法接受 Cyclopia genistoides 浸液的苦味，他们习惯了其他 Cyclopia 物种制成的草药茶略带甜味。通过训练有素的品鉴小组来确定苦味热水平提取物的粗酚类部分中哪个部分对苦味的贡献最大，从而确定 Cyclopia genistoides 苦味浸液中粗酚类部分的苦味强度。在其浸出等效浓度 (IEC) 下测试的含有苯并二氢吡喃酮 (B)、二氢黄酮醇 (X) 和黄烷酮 (F) 的富化部分，分别评分为 5、31 和 13（在 100 分制上）。B 部分主要含有 iriflophenone 葡萄糖苷，被认为不苦。X 部分的主要二氢黄酮醇是芒果苷，其苦味明显（p < 0.05）强于等浓度的其区域异构体异芒果苷。在其 IEC 下，异芒果苷和芒果苷的混合物明显（p < 0.05）比单独的芒果苷溶液苦，表明异芒果苷有苦味抑制作用。
