Congress mashing of malted wheat cultivars from Thailand provide adequate malt extract physicochemical properties suitable for brewing purposes

Abstract

AbstractBackground and ObjectiveThe use of wheat for brewing is associated with its influence on protein content, phenolic compounds, and organoleptic properties, such as mouth feel, haze, and foaming intensity in malt‐based beverages. The quest for alternate malt materials other than barley malt and the exponential growth of micro‐breweries in Thailand have intensified the search for appropriate wheat cultivars suitable for brewing purpose. In this study, four imported commercial wheat malts and three malted wheat cultivars from Thailand (Samerng‐2, Phrae‐60, and Fahng‐60) were compared in terms of their physicochemical characteristics. Malt quality was based on α‐amylase, β‐amylase, antioxidant activities, the contents of free amino acid (FAN), fermentable sugars, total reducing sugar (TRS), and total polyphenol (TPC) of the malt extract samples produced by congress mashing.FindingsThe levels of α‐amylase activity were lower than that for β‐amylase activity in all malt samples. The malt extract (wort) yield was 83.7% weight per weight (w/w), 83.9% w/w, and 83.3% w/w in Samerng‐2, Phrae‐60, and Fahng‐60, respectively. The FAN contents in wort from the three Thai wheat malts were in the range of 155.2–183.4 mg/L. When used as an adjunct at 30% w/w or 50% w/w, the FAN contents were in the ranges 197.5–203.9 and 140.9–173 mg/L, respectively. Sucrose, glucose, maltose, and maltotriose were in the ranges 0.37–1.17, 2.8–4.3, 37.9–48.8, and 7.3–9.68 g/L, respectively. Wort produced contained contents of TRS, total carbohydrate, and TPC of 56.3–57.4, 79.4–88.9, and 116.4–18.2 mg/L, respectively. The antioxidant activity level based on 2,2‐di(4‐tert‐octylphenyl)‐1picrylhydrazyl and 2,2‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt assays was within 61.0–125.4 and 1259–1413 µmol TE/L, respectively.ConclusionThese physicochemical attributes of the Thai malted wheat cultivars were similar to the commercial imported wheat malt samples. Consequently, the Thai cultivar would be suitable as raw brewing material.Significance and NoveltyThis preliminary study is limited to laboratory experimental design. Different conditions and processes could lead to different experimental results. Notwithstanding, this study provides the first report on some physicochemical properties of malted Thai wheat cultivars as the base raw material and adjunct for brewing purposes, which are critical in selecting cultivars for brewing purposes. This will intend to promote the cultivation of local wheat cultivars to meet the demand of local craft breweries.