Pito is an alcoholic beverage obtained through a yeast (Saccharomyces cerevisiae) fermentation of wort extracted from sorghum (Sorghum bicolor L. Moench) malt. The malting conditions of sorghum are thought to influence the quality characteristics of the malt, and subsequently the quality of the pito obtained from it. Studies were carried out on a local sorghum cultivar grown in Ghana -chireh, to optimize the conditions for malting conditions for pito production in Ghana. A 3 3 full factorial experimental design was replicated with steeping times of 12, 16 and 22 h, germination times of 3, 4 and 5 days, and malt drying temperatures of 30, 40 and 50°C as factors. Diastatic power, extract yield, attenuation limit and free amino nitrogen were determined. Germination duration significantly affected diastatic power and free amino nitrogen (p < 0.001). Extract yield was also significantly influenced by germination duration (p = 0.001). The germination time, steeping time and drying temperature had no significant effect on the attenuation limit. The optimal conditions for malting this specific cultivar grown in Ghana to obtain critical malt quality indices are 12.0-12.5 h steeping, 5 days of germination at 30°C and drying at 40°C. Free amino nitrogen levels in all treatments were higher than the minimum requirement for good yeast nutrition and fermentation.

Traditional sorghum beer is reputed for its therapeutic virtues in according the consumers. A number of biological active compounds like phenolic compounds (phenol, tannins, flavonoids, anthocyanins), diets fibers and compounds with clinically demonstrated antimalarial activity (quinine formate, quinine dihydrochloride, chloroquine) and antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl and ferric reducing-antioxidant power methods) were evaluated in sorghum wort and beers fermented by wild yeasts and pure culture of Saccharomyces cerevisiae . The total phenol content in the samples ranged between 1254.69 ± 2.31 and 239.68 ± 11.92 μg/mL GAE. Antioxidant activity with 2,2-diphenyl-1-picryl-hydrazyl analysis method was high in sorghum wort with 73.33 ± 1.15% but with ferric reducing-antioxidant power analysis method, the antioxidant activity was high in beer from pure culture of Saccharomyces cerevisiae. No compounds with clinically demonstrated antimalarial activity were found in the samples. At bioactive compounds (phenolic compounds) content point view, statistical analysis showed similarity between the two beers.

Pito is a traditional fermented beverage produced from malted sorghum or millet grains. Steeping is usually performed at 30°C. Limited information exists on the effect of temperature on the characteristics of the malted grains and the Pito. The aim of this work was to study the effect of varying the steeping temperature (30, 35 or 40°C) on the quality of malt and of the Pito brewed from Kadaga sorghum and to specifically determine the diastatic power, extract yield and attenuation limit of the malt. Total soluble solids, pH and alcohol content, as well as the sensory evaluation of the Pito brewed at both 40 and 30°C were assessed. Results from analysis showed that the 40°C malts had the highest diastatic power (88.1 SDU/g), extract yield (96.75% d.m.) and attenuation limit (78.95%). Pito produced from malt steeped at 40°C yielded a significantly higher alcohol content of 3.54 g/100 g, a total soluble solids of 4.34 and a pH of 3.57 and this Pito was preferred over the traditionally prepared Pito at the steeping temperature of 30°C. Therefore steeping sorghum at 40°C yields a quality malt and a quality Pito. This study should aid in the adoption of sorghum for brewing purposes.

The fermentation profiles, shelf‐life and consumer acceptance of traditional West African sour sorghum beer (pito) fermented with pure commercial starter cultures of lactic acid bacteria (L. delbrueckii) and yeast (Saccharomyces cerevisiae) were evaluated. The beers from this ‘pure culture’ approach were compared with the spontaneous fermentation of pito wort. Lactic acid formation, pH change and extract utilisation were monitored during fermentation. Lactic acid content was used as a measure of sourness to establish the spoilage level of over‐sourness. Further, regression models relating sourness to the time the drink was kept were used to predict the shelf‐life. Consumer acceptance of the product was evaluated using a novel nine‐point hedonic scale. The pure culture and traditionally fermented beers followed similar lactic acid and fermentation profiles but strain‐specific differences were observed. Similar levels of pH, lactic acid level and extract utilisation were achieved. An improvement in shelf‐life of two days was found over traditionally fermented pito. There was no statistical difference between the two pito products for overall liking and taste. However, there was a preference for the aroma of the pure culture pito. It is suggested that the use of pure cultures will facilitate the scale‐up of pito production. © 2019 The Institute of Brewing & Distilling

Physicochemical quality parameters and volatile fermentation by‐products were determined in West African sour sorghum beer (pito) fermented with pure cultures of Lactobacillus delbrueckii and Saccharomyces cerevisiae compared with pito prepared by traditional spontaneous fermentation. Levels of by‐products were also compared with those found in similar beer types. Similar levels of apparent extract, alcohol, pH, lactic acid and bitterness were obtained for pure culture and traditional fermentations, although differences were observed in colour and turbidity. Significant statistical differences were obtained for all of the volatile aroma compounds analysed. The pure culture approach resulted in a higher level of total volatile compounds (353 mg/L) of which higher alcohols accounted for 88%, predominately n‐propanol. The traditional approach had total volatiles of 229 mg/L with 86% higher alcohols but with iso‐amyl alcohol predominating. Ester levels were low in the pure culture beer but with a relatively high level of acetaldehyde. Fermenting pito with pure cultures yielded a product with similar physicochemical quality as traditional pito but with a suggestion of a more pronounced aroma whose impact on the overall product quality will require consumer acceptance and sensory evaluation. © 2019 The Institute of Brewing & Distilling