Abstract
This work studies the physical characteristics of sorghum whole flour particles produced with grains reduced in tannins by hydrothermal treatment. Flours ground with two types of mills: a roll mill and a blade mill were used; grains were hydrated with a moisture content of 25%. For this moisture the maximum yield was obtained. The effect of the grain moisture during the grinding was evaluated regarding the morphological characteristics, the granulometry and fractal dimension (Df) of particles. In all the analysed samples, bimodal size distribution curves were obtained. The treated samples showed medium size particles bigger than the samples without treatment. The samples without hydrothermal treatment presented particles with lower damage than the treated samples for both mills. The difference in Df between samples indicated more roughness for the samples with treatment. The proposed treatment could contribute to the development of sorghum whole flour with different properties for the development of gluten-free food.
Highlights
Sorghum (Sorghum bicolour (L.) Moench) is an important basic food eaten in warm and semi-arid regions of the world
One of these methodologies is based on a hydrothermal treatment (Acquisgrana et al, 2016, 2019, 2020), which is the one that is going to be used in this work
The hydrothermal treatment for tannin reduction consisted in moistening the grains with a 1:2 ratio during an hour at 75 oC, as mentioned in previous works (Acquisgrana et al, 2016, 2019)
Summary
Sorghum (Sorghum bicolour (L.) Moench) is an important basic food eaten in warm and semi-arid regions of the world It is rich in carbohydrates, fibre, vitamins, minerals and phytochemicals, including tannin, phenolic acids, anthocyanin and phytosterol (Girard & Awika, 2018). Conventional size reduction machines for grain preparation in food processing include hammer mills, roll mills and friction mills (Mahasukhonthachat et al, 2010). They vary in the effective operation force and the amount of heat generation through friction during milling. These friction heat and mechanical energy could affect the molecular and structural properties of starch (damaged starch) and other components, which affects its functionality (Liu et al, 2014)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
