The use of response surface methodology to evaluate the fermentation conditions in the production of tepache

 

R.I. Corona-González, J.R. Ramos-Ibarra, P. Gutiérrez-González, C. Pelayo-Ortiz, G.M. Guatemala-Morales and E. Arriola-Guevara

 

 

Due to the artisan nature of the production process of tepache, there is no uniformity in fermentation conditions and raw material used. The fermentation is crucial to the final characteristics of tepache and there is a certain degree of ignorance of related organisms and the level of acceptance among consumers. In this study, tepache fermentation conditions (concentration of sugars, initial pH, temperature and fermentation time) were evaluated to enable correlating the formation of products of fermentation (lactic, acetic and ethanol) with the degree of acceptance of the beverage among consumers. Sensory evaluation was measured on a 9-point hedonic scale. Results were analyzed using the response surface methodology (RSM) which showed that the fermentation conditions for higher acceptance were: 22°C, 10% (mass/volume) of sugars (brown sugar), 72 h of fermentation and an initial pH of 5. According to this study, to have a wider acceptance the beverage must contain about 7 g/L of ethanol, no more than 5 g/L of lactic and acetic acid, and 70 g of sucrose/L. Likewise, yeasts present in the fermentation were identified and it was found that Saccharomyces cerevisiae is the predominant species.