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Question 18M.3.SL.TZ1.b

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Date May 2018 Marks available [Maximum mark: 1] Reference code 18M.3.SL.TZ1.b
Level SL Paper 3 Time zone TZ1
Command term State Question number b Adapted from N/A
b.
[Maximum mark: 1]
18M.3.SL.TZ1.b

Citric acid is produced industrially from sugars in continuous fermenters using the fungus Aspergillus niger and with date syrup as a growth medium. Citric acid is a byproduct of the metabolism of this fungus. The fungus requires a nitrogen source for optimal growth and the impact of different nitrogen sources on citric acid production was investigated. The control received no additional nitrogen.

State two uses for industrially produced citric acid.

[1]

Markscheme

food preservative, flavouring, (stabilizer) in alcohol production

Two answers for 1 mark.

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