Commodity only schools shall be eligible to receive donated commodities equal in value to the sum of the national average value of donated foods established under section
1755
(c) of this title and the national average payment established under section
1753 of this title. Such schools shall be eligible to receive up to 5 cents per meal of such value in cash for processing and handling expenses related to the use of such commodities. Lunches served in such schools shall consist of a combination of foods which meet the minimum nutritional requirements prescribed by the Secretary under section
1758
(a) of this title, and shall represent the four basic food groups, including a serving of fluid milk.