Mead production: fermentative performance of yeasts entrapped in different concentrations of alginate

Abstract

Mead is an alcoholic drink known since ancient times, produced by yeast fermenting diluted honey. However, the production of mead has suffered in recent years, partially owing to the lack of scientific progress in this field. In this study, two strains of Saccharomyces cerevisiae, QA23 and ICVD47, were immobilized in 2 or 4% (w/v) alginate beads to assess the most effective alginate concentration for yeast immobilization to produce mead. Neither of the alginate concentrations was able to prevent cell leakage from the beads. The fermentation length was 120 h for both yeast strains. In all cases, at the end of the fermentation, the number of cells entrapped in the beads was higher than the number of free cells, and the total 4% alginate bead wet weight was significantly higher than the 2% alginate bead wet weight. In addition, the evaluation of mead quality showed that the yeast strain had significantly more influence on the physicochemical characteristics than the alginate concentration. Although the yeasts immobilized in the two alginate concentrations were able to perform the fermentation, further research is needed in order to understand the evolution of the yeast population inside the beads throughout the fermentative process. Copyright © 2014 The Institute of Brewing & Distilling

Production and characterization of mead from the honey ofMelipona scutellarisstingless bees

“…These acids are responsible for the reduction of the pH value, which remains practically unchanged until the end of the fermentation. Our results are corroborated by the observations of Mendes‐Ferreira et al , who found an average value of 3.3 ± 0.2 in mead supplemented with 5 g L −1 potassium tartrate, 3 g L −1 malic acid, 1.0 g L −1 of diammonium phosphate (DAP) and Pereira et al , who found a value of 3.6 ± 0 following fermentation by S. cerevisiae ICV D47 cells immobilized in 2% alginate. These researchers also observed a reduction in pH values during mead production.…”

“…The amount of nitrogen in the honey must reduced from 203.0 ± 0 to 24.1 ± 3.6 and 32.7 ± 4.0 mg L À1 in dry mead and sweet, respectively, with no significant difference (p ≤ 0.05) between the meads. These results are in agreement with the observations in the literature (28,33), which also verified the presence of residual nitrogen when supplementing the honey must with DAP. This may be related to the method used to determine the nitrogen that quantifies other compounds not assimilable by yeast, in particular the amino acid proline.…”

The influence of yeast immobilization on selected parameters of young meads

“…Yeast was trapped behind porous Ca‐alginate membranes, which could restrict the transport of substrates and products. Alginate gel does not prevent the phenomenon of cell leakage and in fermented wort many of the cells are in a free state . Greater addition of immobilized yeast into the worts did not accelerate the process (Fig.…”

“…Continuous mead production performed with Saccharomyces cerevisiae and Hansenula anomala yeast immobilized in calcium alginate enabled the time of fermentation and maturation processes to be shortened (9,10). Several natural matrices have been used for yeast immobilization, such as calcium alginate, κ-carrageenan, calcium pectate, delignified cellulosic materials, gluten pellets and apple pieces (6,(11)(12)(13)(14)(15).…”

Mead and Other Fermented Beverages

“…The capacity of two sodium alginate concentrations, 2% and 4%, to immobilize S. cerevisiae yeast strains QA23 and ICV D47 in the context of mead production was investigated by Pereira et al [84]. Neither of the alginate concentrations was able to prevent cell leakage from the beads.…”