Fat acidity as a deterioration sign during pearl millet (Pennisetum glaucum (L.) R. Br) flour storage

Grains of pearl millet (Pennisetum glaucum ( L.) R. Br) cultivars from two regions in Algeria were used to investigate the effect of processing treatments (steaming, blanching, micro-waving, acid soaking, and fermentation) and storage conditions (ambient temperature and 4 degrees C) on sensory quality and shelf-life of the flour during 4 months of storage. Fat acidity and moisture were assayed for all treatments, besides rancidity signs. The results showed that storage conditions had no effect on fat acidity of the control-sample. Steaming and chemical treatment significantly reduced fat acidity by 43.08% and 39.28%, and moisture by 21.61% and 37.36%, respectively, of flour stored in ambient temperature. At 4 degrees C, same treatments reduced fat acidity by 52.06% and 52.75%, and moisture by 5.69% and 23.80%, respectively. Fermentation particularly increased fat acidity by 3.99% and moisture by 7.67%, of flour stored in ambient temperature. At 4 degrees C, it increased moisture by 32.12%. Dry-thermal treatment particularly reduced moisture by 52.85%, of flour stored in ambient temperature. At 4 degrees C, it reduced by 43.84%. Steaming and blanching treatments did not show any effect on flour general acceptability, while fermented flour was no more acceptable after 10 days of storage. The one-way analysis of variance (ANOVA) revealed that there is no significant difference (p < 0.05) between the two study regions data. The storage conditions have shown significant effects (p < 0.05) on the fat acidity of pearl millet treated flour after 30 days of storage.