Successive Fermentation of Aguamiel and Molasses by Aspergillus oryzae and Saccharomyces cerevisiae to Obtain High Purity Fructooligosaccharides

Abstract

Fructooligosaccharides (FOS) are usually synthesized with pure enzymes using highly concentrated sucrose solutions. In this work, low-cost aguamiel and molasses were explored as sucrose alternatives to produce FOS, via whole-cell fermentation, with an Aspergillus oryzae DIA-MF strain. FOS production process was optimized through a central composite experimental design, with two independent variables: initial sucrose concentration in a medium composed of aguamiel and molasses (AgMe), and inoculum concentration. The optimized process—165 g/L initial sucrose in AgMe (adjusted with concentrated molasses) and 1 × 107 spores/mL inoculum concentration—resulted in an FOS production of 119 ± 12 g/L and a yield of 0.64 ± 0.05 g FOS/g GFi. Among the FOSs produced were kestose, nystose, 1-fructofuranosyl-nystose, and potentially a novel trisaccharide produced by this strain. To reduce the content of mono- and disaccharides in the mixture, run a successive fermentation was run with two Saccharomyces cerevisiae strains. Fermentations run with S. cerevisiae S227 improved FOS purity in the mixture from 39 ± 3% to 61.0 ± 0.6% (w/w) after 16 h of fermentation. This study showed that agro-industrial wastes such as molasses with aguamiel are excellent alternatives as substrate sources for the production of prebiotic FOS, resulting in a lower-cost process.

Aguamiel Enhance Proteolytic Activity and Survival of Lactiplantibacillus pentosus ABHEAU-05 during Refrigerated Storage of a Fermented Milk

“…It is a source of prebiotics due to its fructan content and has the potential to be used in different branches of the food industry as a functional drink [15][16][17]. It is because of its composition that it is an excellent raw material to carry out fermentation [18,19], and being an aqueous medium with a large number of carbohydrates as substrates, it represents a favorable substrate for the growth of microorganisms and for the biotechnological production of high purity FOS [20][21][22]. This product has been used successfully to manufacture symbiotic foods such as fermented milk and cheese [18,19].…”