Characterization of the composition and the techno-functional properties of mannoproteins from Saccharomyces cerevisiae yeast cell walls.

Broad molecular weight (MW) distribution and variability of mannan to protein ratio of purified mannoproteins (MP), isolated from yeast cell walls upon the enzymatic treatment, revealed their multiplicity. The main fraction of high-MW Agrimos®-MP1 and YCW-b-MP1' contained mannoproteins with a mannan to protein ratio of 3.5 and 6.9, respectively. Low-MW YCW-b-MP2' was mainly comprised of mannan, with a ratio of 181, whereas low-MW Agrimos®-MP2 was characterized by a ratio of 12.2. The solubility of MP1/MP2 was higher than that of MP1'/MP2'. Mannoproteins showed similar or lower solubility than mannan, and they exhibited a Newtonian behaviour. Sonication was the appropriate method for the formation of mannoproteins-based emulsions. Contrary to MP1/MP1'-based emulsions, MP2/MP2'-based ones showed higher affinity towards soybean oil than glyceryl-trioleate. pH affected the emulsifying ability of MP1/MP1'. MP1/MP1' showed similar or slightly inferior emulsifying properties than lecithin. This study is expected to broaden the applications of mannoproteins as value-added ingredients.