Effects of Date Extract Addition on Kinetic and Physicochemical Parameters of Sour Craft Beer Fermented with Lachancea spp. Under Optimal Conditions

The style of a beer is determined by the combination of malts and hops, and the type of yeast used. The incorporation of date fruits into the fermentation process with non-conventional yeasts such as Lachancea spp. results in effective fermentation, influencing the kinetic parameters of yeast growth and prompting different physicochemical properties in the resulting beverage. The brewing process for a sour beer with Lachancea spp. yeast was optimized using a central composite rotational design and response surface methodology, and the growth kinetics were calculated. The optimal conditions required 500 g of dates, incorporated 59.46 h after starting the fermentation process. The results revealed a total phenolic content of 254.81 mg GAE/g, and the amount of titratable acidity was 2.66%. Under favorable operating conditions, the growth kinetic parameters of Lachancea spp. yeast revealed a rate of 0.78 μ.h−1 and a growth constant of 3.29 k (g/h). The addition of dates 60 h into fermentation with Lachancea spp. allows for technical control of acidity and efficient fermentation kinetics for the creation of sour craft beers.