Abstract:
Even when fresh, non-alcoholic, and low-alcoholic beers (NABLABs) exhibit significant staling defects due to premature oxidation. In this study, the antioxidant power of eleven fresh commercial NABLABs was assessed by means of three different assays: the oxygen radical absorbance capacity (ORAC), the linoleic acid-induced oxidation (TINH), and the indicator time test (ITT). Only the first two assays, both involving radicalar degradations initiated by AAPH, were found to correlate with each other. NABLABs displayed lower ORAC values than conventional beers (on average, 6127 μmol eq. Trolox/L), except for three samples made with special-colored malts or dry-hopped. Dealcoholization was the step with the greatest impact on the ORAC value (up to a 95% loss) and on flavan-3-ols, sotolon, and polyfunctional thiols, while pasteurization strongly affected color, TBA, and Strecker aldehydes. ORAC assays applied to hop, alternative cereals, and various botanical ingredients indicated that mashing with red sorghum, dry hopping/spicing, and wood maturation could bring the antioxidant power of a NABLAB close to those of conventional beers. With an ORAC value not reached by any other tested botanical ingredient (5234 µmol eq. Trolox/g), African Vernonia amygdalina leaves (traditionally used for Rwandan Ikigage beers) emerged here as the best candidate.
摘要:
即使新鲜,不含酒精,和低酒精啤酒(NABLABs)由于过早氧化而表现出明显的陈腐缺陷。在这项研究中,通过三种不同的测定法评估了11种新鲜商业NABLABs的抗氧化能力:氧自由基吸收能力(ORAC),亚油酸诱导的氧化(TINH),和指标时间测试(ITT)。只有前两个化验,两者都涉及AAPH引发的自由基退化,被发现相互关联。NABLABs的ORAC值低于传统啤酒(平均而言,6127μmol当量。Trolox/L),除了三个用特殊颜色的麦芽或干啤酒花制成的样品。脱醇是对ORAC值(高达95%的损失)和黄烷-3-醇影响最大的步骤,sotolon,和多官能硫醇,而巴氏灭菌强烈影响颜色,TBA,和Strecker醛.ORAC检测应用于啤酒花,替代谷物,各种植物学成分表明用红高粱捣碎,干跳跃/香料,木材成熟可以使NABLAB的抗氧化能力接近传统啤酒。任何其他测试的植物成分均未达到ORAC值(5234µmol当量。Trolox/g),非洲Vernonia杏仁树叶(传统上用于卢旺达伊基格啤酒)在这里成为最佳候选者。