They were being held in custody and would be grilled by investigators from the police department charged with looking into breaches of public health and environmental violations.
The arrests follow a judicial enquiry launched in March into Spanghero for aggravated fraud and mislabelling of food products.
Spanghero, which has been renamed La Lauragaise, was identified by the French government as the main player in the horsemeat scandal that saw mislabelled products sold in several European countries and Hong Kong.
Spanghero's sanitary licence was revoked and the company, which had employed 360 workers before the scandal, closed shop in June. It resumed activities two months later with new management and backed by two new financiers.