Popis: |
Strains of Saccharomyces cerevisiae ferment slowly and give beer of high specific gravity in nutrient-depleted worts produced by substituting carbohydrate syrup for malt. Yeast performance cannot be fully restored by the provision of increased quantities in wort of either amino nitrogen, as serine, or dissolved oxygen. Serine and improved oxygenation act together synergistically and are fully effective. The new situation, in which attenuation pattern is normal, nevertheless differs in several respects from that in malt wort, notably with regard to yeast yield and production of higher alcohols and esters. |