Fermentation
Name two things that must be added directly into the production chamber of the fermenter that microorganisms need.
Air (containing oxygen) and nutrients
What type of substance is penicillin?
Antibiotic
Name the substance that makes the enzymes.
proteins
Why is air pumped into the fermenter?
To give the microorganism a supply of oxygen.
What is the ideal pH for producing penicillin in a fermenter?
pH 6.5
All enzymes are proteins but all proteins are not enzymes. Explain
It means that proteins will have other functions like haemoglobin is made of proteins but it is not an enzyme.
Which part of the fermenter helps to regulate its temperature?
The water jacket
What is the ideal temperature range for growing penicillin in a fermenter?
Approximately 23-28oC
Why the juice appears clear once pectinase is added?
Adding pectinase to fruits also helps to produce a clearer juice as larger polysaccharides like pectin can make the juice seem cloudy – once they are broken down into smaller molecules, the juice becomes clearer
What are the stirring paddles in the fermenter for?
To mix everything evenly and ensure there are no 'pockets' of microorganism with no oxygen/nutrients etc.
Why is air sterilised before it enters the penicillin fermenter?
To kill any microorganisms already present in the air and prevent contamination.
Why biological washing powder should not be used in boiling water?
The enzymes itself can get denatured if temperature is too high
Explain how the cooling water inlet/outlet helps control temperature?
Cooling water flows in via the inlet and out via the outlet. It flows around the fermenter inside the water jacket and cools the fermenter, ensuring the ideal temperature throughout and making sure the fermenter doesn't heat up due to aerobic respiration of the microorganism inside the chamber.
Why is a penicillin fermenter likely to heat up during the production process?
Penicillium is an aerobic fungus, so uses oxygen to respire. Heat is produced during respiration, so the fermenter will therefore heat up.
Explain how pectinase helps in the manufacture of fruit juice.
The cell wall of a fruit (apple) contains pectin (found in the middle lamella). Adding Pectinase can speed up the process of breaking down the pectin molecules in the cell wall therefore releasing fruit juice. It also helps in making the juice clear.