The acquisition is expected to complete in three months, following approval from the competition authorities.
CSM Benelux, which is based in Merksem and supplies bakery fats to Belgium, the Netherlands and France, employs around 100 people and turned over more than £890M last year.
Across the world
AAK, which has its head office in Sweden and oil refineries across the world, said it expected Merksem to contribute to the company's operating profit in the second half of 2015.
Jens Wikstedt, AAK’s Europe president, said the acquisition was an important part of the company’s growth plans.