MOS Burger will start a big campaign Friday to try to win back customers who have drifted away in the increasingly competitive fast food industry.

MOS Food Services Inc. is introducing new ingredients for its hamburgers and for the first time, will offer discount coupons. The coupons mark a turning point for MOS, which has traditionally targeted the high-end market rather than competing for the lowest prices as is typical in the fast-food industry.

MOS also announced that it will start using a mixture of ground beef and pork in most of its meat patties, replacing the 100-percent Australian beef it has been using since 1997.