Edible protein per unit area of land

Edible protein per unit area of land is a measure of agricultural productivity. This measure for various major foodstuffs is shown in the chart below. Values are expressed for one calendar year. Biological Values and usable protein values have been added to the chart to show the true relative value of each foodstock for human consumption. Usable protein values are determined by the Biological Value of each foodstuff and represent the amount of protein that is fully digested by humans, it is calculated as follows (Edible protein * Biological Value = Usable protein).

	Edible protein		BV	Usable protein		Limiting amino acid
	(g/m²)	(lb/acre)	(%)	(g/m²)	(lb/acre)
Soybeans	40.0	356	74	29	263
Rice	29.0	260	86	25	224	lysine
Legumes (average)	22.0	192	49	11	94	tryptophan
Milk	9.2	82	91	8.4	75	methionine or cysteine
Wheat	15.0	138	54	8.1	75	lysine
Eggs	8.5	76	94	8.0	71
Maize	24.0	211	32	7.7	68	tryptophan
Meat (average)	5.0	45	80	4	36
Beef	2.2	20	78	1.72	15.6	phenylalanine or tyrosine
Selected averages as computed in the 1970s

See also

• Biological Value
• Essential amino acids
• Protein

References

• John Lobell (1981); The Little Green Book: A Guide to Self-Reliant Living in the 80's. Boston: Shambhala. ISBN 0-394-74924-3