MB UNIT 8B: WINE PRODUCTION

5 flashcards · Other · by Yaiza Anido

1. Briefly explain what wine is

   Wine is the alcoholic fermented joice of fresh grapes used as a beverage. Different varieties of grapes and strains of yeast produce different types of wine. Yeast + sugar (grapes)= EtOH + CO2 + T

2. How is yeast involved in the production of wine

   When grapes are harvested they are then converted with a buch of microorganisms including yeast. There are a lot of wild yeast which do not make good wine and also other spoilage organisms and bacteria, in order to kill the wild yeast and inhibit the growth of these spoilage organisms the grapes are treated with 30 to 50 ppm of SO2. There are 2 types of ferementations that yeast can undergo: spontaneous feremntation and inoculated fermentation

3. Explain what is spontaneus fermentation

   During spontaneus fermentation, we have a low concentration of microbes on the grapes meaning that the fermentation will take longer to start and the process overall will take more time. In this type of fermentation, wild yeast may not have favorable traits which may lead to low alcohol tolerance and high sugar content.

4. Explain Inoculated fermentation

   High amoutns. The innoculum will outcompete other microorganisms present. The preffered yeast for this is Saccharomyces cervisiae.

5. How can we get the best yeast for inoculation?

   Target sugar trasnport Improve ethanol tolerance Improve SO2 resistance Improve N2 assimilation