Caracterización del proceso fermentativo de Aspergillus niger P.E.L. Van Tiegghem utilizando como sustrato cáscara de papa (Solanum tuberosum L.) para el enriquecimiento proteico

Abstract

Potato (Solanum tuberosum L) is one of the most frequent tubers in Ecuadorian’s basic food basket; it has a high demand in the market and its main use is in the food industry, however, the accumulation of its waste has become a problem, even though, biotechnological advances allow using this type of waste and generate other improvements through fermentation processes giving changes in its final composition. It has been shown that some fungi, such as Aspergillus niger, which are able to modify their metabolic pathway and increase in their final percentage of macronutrients The objective of this study was to characterize the fermentation process of Aspergillus niger using potato’s peel (Solanum tuberosum L.) as a substrate to the protein increase in the medium. In the initial phase, the fermentation time (5-8 days), the agitation speed (0-60 rpm) and the inoculum concentration (5000 and 50,000 conidia for gram of medium) were evaluated through a factorial design (23), these factors were important for the fermentation process; subsequently, fermentation was optimized and kinetic parameters were determined. Optimization resulted in a protein concentration of 16.3092 mg for ml and a biomass concentration of 0.9422 g for ml. Finally, the kinetic parameters of the microorganism in the optimized medium were determined obtaining a specific growth rate 𝑢= 0.005708 ℎ-1, a doubling time T = 121.42 ℎ and a yield 𝑌𝑥/𝑠 = 0.5074 g of biomass for mg of substrate consumed. The results obtained confirmed that there was an increase in the final protein level of the medium.