Brewing characteristics, physicochemical constituents, and antioxidant activity of the infusions of colored highland barley roasted at different times

Effects of roasting and steeping on nutrients and physiochemical compounds in organically grown naked barley teas

“…Previous studies also reported that the levels of soluble β-glucan were constant in roasted barley grains at temperatures below 200 °C ( Montanuci et al, 2016 ) and the amount of total β-glucan was not affected by the roasting process in different barley cultivars ( Sharma, Gujral, & Rosell, 2011 ). The β-glucan contents in barley teas measured in this study was similar to the concentrations recently reported by Wang et al (2023) (0.007–0.015 g/100 g). We extended the analysis from roasted barley to barley tea and our findings directly contradict the popular press descriptions of barley tea as a source of dietary fiber (See Supplementary Table 2 for a partial listing of websites and product labels).…”

“…Furthermore, we did not detect these compounds in roasted grains, a presumed consequence of their low stability during roasting. However, the total phenolic compounds content in our teas was similar to that reported by Wang et al (2023) . The content of phenolics in the roasted barley teas will ultimately be dependent on the barley grain matrix and which compounds can be extracted in a water-based solution, as many phenolics are more soluble in solvents rather than water ( Cuevas-valenzuela, González-rojas, Wisniak, Apelblat, & Pérez-correa, 2014 ).…”

“…Five of these compounds have also been detected in highland barley teas, but information on concentration levels were not provided ( Nie et al, 2022 ). Unlike Wang et al (2023) who quantified total phenolics and total flavonoids in infusions based on roasted colored barley, we did not detect flavonoids in any of the teas we analyzed. Furthermore, we did not detect these compounds in roasted grains, a presumed consequence of their low stability during roasting.…”

“…Health-promoting properties of barley tea are often attributed to phytochemicals present in the raw grain ( Patra et al, 2023 ) without taking into account the possible effects of roasting and steeping of the roasted grain. There are mixed reports in the literature on the levels of major bioactive compounds, such as β-glucan and phenolic compounds, present in barley tea ( Kulkarni, Yokota, Suzuki, & Etoh, 2008 ; Oh, Kim, Park, & Lee, 2015 ; Seo et al, 2015 ; Wang et al, 2023 ). Unique properties of barley tea include its flavor, aroma, and color and the roasting process is a primary determinant of these attributes ( Schlörmann et al, 2019 ).…”