Saccharomyces cerevisiae yeast is widely used in the commercial production of bioethanol and alcoholic beverages from plant sugars.
Name the kingdom of organisms that includes Saccharomyces.
What is meant by the term anaerobic?
Write the word equation for anaerobic respiration (fermentation) in yeast.
During commercial fermentation, the sugar solution is pasteurised and the fermentation vessels are sterilised.
Describe one method, other than heating, that can be used to sterilise the equipment.
Why is it important to use sterilised equipment?
The primary carbohydrate source used in some fermentations is sucrose.
Name the enzyme that hydrolyses sucrose.
Name the two simple sugars produced when sucrose is hydrolysed.
During the fermentation process, the population of live yeast cells initially increases, but eventually decreases towards the end of the process. Explain why the number of live yeast cells decreases towards the end of the process.
74 exam-style questions on Edexcel IGCSE Biology Food production. Each one has a worked solution and a mark scheme showing where the marks go.