CEB-Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.
Misión Biológica de Galicia, Consejo Superior de Investigaciones Científicas (CSIC), El Palacio, Salcedo, 36143 Pontevedra, Spain.
Molecules. 2020 Jul 15;25(14):3228. doi: 10.3390/molecules25143228.
Cassava plays a key role in the food production and economies of several countries worldwide. Due to its starch content, alcoholic fermentation is a promising transformation process for adding value to cassava. However, most of the existing cassava beverages are from traditional origin, with the yields and quality often poorly known or controlled due to the use of artisanal production processes. This work aims at the application of easily implementable biotechnological tools for the production of cassava spirits, in order to add value to this raw material. Cassava flour was liquefied and saccharified using enzymatic cocktails, generating a fermentable broth with ~184 g L of fermentable sugars. This was then fermented into an alcoholic product with ~10% ethanol by volume and distilled for spirit production. Cassava spirits with 40% ethanol by volume, with or without application of oak wood, were produced. For further valorization, volatile fractions of cassava spirits were characterized by gas chromatography-flame ionization detection (GC-FID) and GC-MS. These showed a predominance of yeast fermentation metabolites, complemented by wood extractives where oak chips were applied. Both produced spirits showed desirable sensory traits, receiving good acceptance by experienced tasters, demonstrating the feasibility of the proposed process to add value to cassava surplus.
木薯在全球多个国家的粮食生产和经济中发挥着关键作用。由于其淀粉含量，酒精发酵是一种有前途的增值转化过程，可用于木薯。然而，由于采用了传统的手工艺生产工艺，大多数现有的木薯饮料都源自传统，其产量和质量往往知之甚少或难以控制。本工作旨在应用易于实施的生物技术工具生产木薯烈酒，以提高这种原料的附加值。使用酶制剂混合物将木薯粉液化和糖化，生成可发酵糖浓度约为 184 g/L 的发酵液。然后将其发酵成体积分数约为 10%的酒精产品，并进行蒸馏以生产烈酒。分别生产了体积分数为 40%的木薯烈酒，以及是否应用橡木片。为了进一步增值，通过气相色谱-火焰离子化检测（GC-FID）和 GC-MS 对木薯烈酒的挥发性成分进行了表征。结果表明，酵母发酵代谢产物占主导地位，橡木片应用时则补充了木材浸提物。两种生产的烈酒都具有理想的感官特性，经验丰富的品尝者给予了很好的评价，证明了该工艺对木薯剩余物增值的可行性。
