| The chemical-nutritional characteristics of the flor yeast Saccharomyces cerevisiae (beticus), obtained from sherry wine, was studied, during the fermentative phase and in the velum phase. The protein quality was evaluated by means of chemical methods. For comparative effect, the analyses were also conducted on a fermentative strain, which cannot form velum and in an edible yeast. This study included protein complementation and classification of the proteins.; The results of the analyses demonstrated a higher cellular viability for the yeast flor than for the fermentative strain. The membrane proteins of the flor yeast presented an increase from the fermentative phase to the velum phase (from 15 to 24%), whereas the lipids increased from 5.8% to 6.4%.; The majority acids in all strains were: palmitic, estearic and oleic. The flor yeast displayed a higher content of oleic acid content than the fermentative strain (30 against 10%). When changing for the phase velum, the flor yeast presented a decrease in the contents of palmitoleic acid and estearic acid, and an increase of the contents of the oleic, behenic and lignoceric acids.; The amino acidic profile of the flor yeast revealed a balanced standard when compared with the FAO data (1991), showing the sulphured amino acids as limiting and a high content of lysine. The studies of quality of the protein of the flor yeast indicated a digestibility of 82%, in the fermentative phase, and 83%, in the velum phase, and a chemical score of 73.6 and 75.2, in both the phases, respectively. The PDCAAS index for flor yeast in the velum phase was 0.62 and the MEAA index was 89.55. The flor yeast proteins demonstrated higher levels of prolamins and globulins, when compared with other studied strains.; Finally, the protein complementation of flor yeast with vegetal raw materials, suggests mixtures with high nutritional standards. |
