And he said the foodservice part of the business, which supplies hospitality businesses like restaurants and bars, had suffered, along with parts of the business which supply alcohol - including Drinks Inc, the distributor Musgrave took over last year.
Mr McCormack told Business Telegraph that as the year goes on and restrictions are lifted, hospitality sales will go up.
"It's not clear how long will it take to get back to where it was but I think middle or end of next year," he said.
Musgrave employs around 1,500 people in Northern Ireland. It is one of the island's biggest businesses, and reported sales of €3.9bn in 2018.