Physicochemical study of pinhão flour as source of adjunct in beer production

Pinhão seed flour can be used as a soluble adjunct in the production of beer. The objective of this work was to determine the proportion of pinhão flour and barley malt to obtain a suitable extract for beer production. In addition, as a source of starch it is important to determine the viscoamylographic properties and chemical composition. To achieve this, three samples of pinhão flour were manufactured: raw, frozen raw and pre‐gelatinised flour. Of these, pre‐gelatinised pinhão flour was compatible with the brewing process, with low gelatinisation point and low viscosity. Raw and frozen raw flour showed a high gelatinisation point (> 78°C) which required the same pre‐treatment as processed corn and rice. The total starch yield for pinhão flour was 63.8% on a dry basis. The most effective blend was 20% of pinhão pre‐gelatinised flour and 80% malted barley. This increased the yield by 10%, thereby proving economically attractive. The pinhão flour adjunct contributed no functional enzymes to the mashing process, made no contribution to beer colour and made a positive contribution to the body and head retention. This influenced the filterability and the colloidal stability of the beer. The use of pinhão flour as a brewing adjunct does not require chemical agents or pre‐treatment. The pre‐gelatinisation and drying procedures provide a simple and cheap method for obtaining pinhão flour for both pilotscale and commercial production. © 2018 The Institute of Brewing & Distilling