WineMicrobiologyMyOne

Question 1

What is acetic acid

Answer 1

principal acid in vinegar - bad taste

Question 2

what is difference b/w brettanomyces and dekkera

Answer 2

brettanomyces purely asexual

Question 3

Spoilage characteristics

Answer 3

• Volatile acidity - acetic acid (vinegar) and ethyl acetate (nail polish remover)
• Brett character (dekkera)
  +Horsey, leathery smell
  +harsh metallic after taste
  +volatile phenols results in taste of brett character. 4- ethylphenol and 4 ethylguaiacol - 4 EP and 4 EG
  volatile phenols and other compounds
• Mousy off flavours (dekkera)
  + a flavour not an aroma (like cage of mice smell)
  +N heterocycles cause flavour (cyclic molecules)

Question 4

Control of brettanomyces/ reduction in incidence

Answer 4

• general sanitation - clean winery
• Residual nutrients - don’t let grape mature too long, have too high lvls of glucose, fructose, and nitrogen (definitely