Development of diet cereal bar sweetened with stevia leaves pre-treated with ethanol

Abstract The objective of this work was to perform the ethanolic pretreatment of stevia leaves from the plant Stevia UEM-13 line and to characterize its physical-chemical properties aiming its use as a sweetener in the development of a diet cereal bar. The same formulation of the cereal bar with stevia leaves without pretreatment was elaborated for comparative purposes. The following ingredients were used in the preparation of the produtc: fine oat flakes, no sugar granola, cranberry, dehydrated apricots, water, gum acacia and stevia leaf pretreated (F1) and without treatment (F2). According to the results, the diet cereal bars presented significant amounts of crude fiber, protein and antioxidant activity. The product was microbiologically safe for human consumption, reporting lower microbiological valuesthan those foreseen by official regulation. The overall sensory evaluation indicates that the two formulations did not present statistically significant differences regarding the analyzed attributes, being the averages between “liked very much” and “moderately liked”. However, considering the group of cereal bars consumers, the formulation sweetened with pretreated leafs (F1) was found more than twice the acceptance regarding to the formulation sweetened with the leaf in natura (F2). These results demonstrate a viable option of a diet food product naturally sweetened.

摘要 本研究旨在对甜叶菊（Stevia）UEM-13品系叶片实施乙醇预处理，并表征其理化特性，以期将其作为甜味剂应用于膳食型谷物棒的开发。为开展对照研究，本研究同时制备了采用未预处理甜叶菊叶片配制的同款谷物棒配方。本次产品制备所用原料包括：细燕麦片、无糖格兰诺拉麦片、蔓越莓、脱水杏干、水、阿拉伯胶，以及经乙醇预处理的甜叶菊叶片（F1组）与未处理甜叶菊叶片（F2组）。结果显示，两款膳食型谷物棒均含有丰富的粗纤维、蛋白质与抗氧化活性成分，且微生物学安全性满足人类食用要求，其微生物检测数值显著低于官方法规预设的限值。整体感官评价结果表明，两款配方在各项分析属性上均无统计学显著性差异，平均评分介于“非常喜爱”与“中度喜爱”之间；不过针对谷物棒消费者群体的调研显示，经预处理甜叶菊叶片增甜的F1组配方，其接受度是天然状态下叶片增甜的F2组的两倍以上。上述研究结果证实，该天然甜味的膳食食品是一种具备可行性的产品开发方向。