Browsing by Subject "OatHow"

The popularity of oats (Avena sativa L.) as a food grain and their use in plant-based foods has increased in recent years due to, among other things, the proven positive health effects of oat components. Oat saponins are bioactive compounds that can potentially affect health (both positively and negatively), as well as technological properties and taste of oats and oat products. The main saponins of oat grain are avenacosides A and B. The aim of this study was to investigate the variation of avenacoside concentrations in oats grown in Finland. The samples were 20 batches of laboratory-scale dehulled, unheated oat grains (groats, G samples). In addition, the effect of processing on avenacoside concentrations was investigated for the same 20 grain batches. Oat processing included a milling process, including heat treatment, flaking, and grinding (NFL samples), and bread making (LP samples). In addition, the effect of storage (6 months at room temperature) of NFL samples on avenacosides concentrations was studied. Avenacosides were extracted from the samples with methanol-water solvent overnight at room temperature and determined by high performance liquid chromatography. The results of the study showed that the mean avenacoside concentrations in the G samples ranged from 371 to 721 µg/g dry matter. Concentrations among G samples were statistically significantly different (p<0.05). The differences may be due to genetic factors and oat growth conditions. As a result of processing, avenacoside concentrations decreased in the following order: G> NFL> LP. The milling process reduced avenacoside concentrations by an average of 26% (G vs. NFL). Bread saponin concentrations were on average 49% lower than those in oat flake flour (LP vs. NFL). Overall, concentrations decreased by an average of 62% (G vs. LP). Presumably, saponin concentrations could have been affected e.g. by heating and β-glucosidase enzyme (endogenous in NFL and produced by yeast in LP). The storage experiment showed that avenacosides were stable in NFLs during six months of storage. Data obtained can be used in other oat saponin studies and in the development of oat products. The study provided important information about the effects of oat processing on avenacoside concentrations and can be continued by analysing avenacosides levels under different baking conditions and taking samples at different production stages. The effect of storage on avenacosides under different conditions could be also studied.