Black bean is one of the important beans as the second most consumed bean globally after soybean. It has been reported as a sustainable source of anthocyanins, important natural colorants used in food and consumer products. However, industrial uses of black bean anthocyanins in pharmaceutics and cosmetics have rarely been explored. Thus, here, a black bean anthocyanin extract was prepared, quality controlled and developed into an efficient hair coloring product. Black bean was macerated in hydrochloric ethanol to produce a dark-reddish 1.85 ± 0.04% dry extract with total anthocyanin content (TAC) of 1.24 ± 0.48 µg/ml cyanidin-3-glucoside. The extract was readily dissolved in propylene glycol (25%), giving a reddish to red-brownish solution at pH of 4.00–7.00. The addition of antioxidant significantly (p = 0.000) enhanced the stability of the extract in an accelerated stability test (90.34 ± 5.32 from 67.83 ± 3.45% TAC remaining). Three base hair gels containing different thickeners were developed to yield clear gels with a viscosity of 101,666.67–447,333.33 cps and a pH of 4.80–4.97. The gel base with the best hair application properties was chosen to mix with 8, 10 and 12% black bean extract to produce similar visually assessed red-brown gels (L* = 33.25–33.76, a* = 0.06–0.09, b* = − 0.45–0.38 and h* = 277.54–283.31) at 73,733.33–99,666.67 cps and a pH of 5.00–5.01. All of the black bean hair coloring gels were stable under the accelerated test. The 10% hair gel was tested for its hair staining efficacy. The black bean hair coloring gel was found to efficiently color hair, and the color was maintained through four washings. An alternative application approach of using black bean as a natural colorant is presented here, including its basic requirements for preparation and quality control from an industrial aspect. The efficient semi-permanent hair coloring product containing black bean is an innovative natural product and is considered as one progress towards a sustainable bio-based economy using a readily available industrial crop, black bean.

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黑豆的替代应用方法：染发产品

黑豆是重要的豆类之一，是仅次于大豆的全球第二大消费豆。据报道它是花青素的可持续来源，花青素是食品和消费品中使用的重要天然色素。然而，很少研究黑豆花青素在药物和化妆品中的工业用途。因此，这里制备了黑豆花色苷提取物，对其质量进行了控制，并发展成为一种有效的染发产品。将黑豆浸入盐酸乙醇中，制成深红色1.85±0.04％的干提取物，总花青素含量（TAC）为1.24±0.48 µg / ml花青素3-葡萄糖苷。提取物很容易溶于丙二醇（25％），在pH 4.00–7.00时产生从红到红棕色的溶液。明显添加抗氧化剂（p = 0。000）在加速稳定性测试中提高了提取物的稳定性（剩余的TAC为67.83±3.45％，为90.34±5.32）。开发了三种包含不同增稠剂的基础发胶，以产生透明的凝胶，其粘度为101,666.67–447,333.33 cps，pH为4.80–4.97。选择具有最佳护发性能的凝胶基质，将其与8％，10％和12％的黑豆提取物混合，以产生相似的外观评估的红棕色凝胶（L * = 33.25–33.76，a * = 0.06-0.09，b * = − 0.45–0.38，h * = 277.54–283.31），温度为73,733.33–99,666.67 cps，pH为5.00–5.01。所有黑豆染发凝胶在加速试验下均稳定。测试10％发胶的染发功效。发现黑豆染发凝胶可有效地染发，并且通过四次洗涤保持颜色。本文介绍了使用黑豆作为天然着色剂的另一种应用方法，包括从工业角度对黑豆的制备和质量控制的基本要求。含有黑豆的高效半永久染发产品是一种创新的天然产品，被认为是使用易于获得的工业作物黑豆向可持续的基于生物的经济发展的一项进步。