The plant in Dalry, which has 500 staff, makes 50 per cent of DSM's total vitamin C output as well as the vitamin B5.
DSM said the job cuts are "a necessary step in view of the fierce competition in vitamins C and B5".
DSM has already reduced personnel at its plants in Italy, France, Belgium and Sisseln, Switzerland, where it makes vitamin E. Current economic conditions have pushed up raw material prices and weakened chemicals demand.
But vitamin production is also being hit by "competitive pressure from the East, such as China and India…accompanied by a global overcapacity for certain products", said DSM.
Pressure on vitamin C is such that DSM is also considering other options to improve its competitive advantage against the four significant Chinese players.
Vitamin C is DSM Nutritional Products' biggest selling vitamin in volume.
"It is no secret that we're looking at vitamin C in terms of the next step. The Chinese have done an excellent job in terms of coming onto the market and getting a significant presence. Now there is a reason to look at how we deal with that," said Bob Hartmayer, chief operating officer, in a recent interview with NutraIngredients.com.
Joint ventures with Chinese companies could be a possible move, he said.
The vitamin is also made in Belvedere in the US, next in line for the cost-cutting review along with the China plants, which produce vitamins A and E for the local market.