General Foods Corp., the nation's largest coffee roaster and food manufacturer, reported higher fourth quarter profits and sales today.

Fourth quarter profits rose to $42.8 million (86 cents a share) from $37.4 million (75 cents a share) for the same period a year ago on sales of $1.5 billion compared to $1.2 billion last year.

For the full year ended April 2, profits totaled $177.3 million ($3.56 a share) against $150.4 million ($3.02 a share) for the previous year. Sales increased to $4.91 billion from $3.98 billion a year ago.

Chairman James L. Ferguson said the dramatic rise in world coffee prices "narrowed percentage margins" in the company's coffee division "which resulted in lower margins for the coproration as a whole."

He said domestic grocery operations had "an exceptionally strong year," although the Burger Chef fast food operation and W. Atlee Burpee gardening division recorded losses for the year.

International operations "turned in asound performance," Ferguson said, despite high green coffee costs and economic problems overseas. While franchises were strengthened, total volume increased and market share gains were made, Ferguson said price controls an d currency fluctuations in some countries eased profits from last year's record levels.

Foreign exchange losses reduced the year's profits by $13.7 million.

Ferguson said he expects first quarter 1978 results to top those of last year.