Best assessment of protein quality is done through:

Ref: Park s Textbook of Preventive and Social Medicine, 22nd edition. Page 588Explanation:Protein Energy Ratio (PER)It assesses the quantity of protein rather than quality.Its percentage of energy provided by protein in diet.PER = Energy from Protein/Total Energy in DietNet Protein Utilization (NPU)The best measure as it uses both biological value (PBV) and digestibility co-efficient (DC).It is measure of protein retained out of consumed.It is product of PBV and DC divided by 100.Protein requirement inversely proportional to NPU of protein.NPU of average Indian diet is assumed to be 65(50-80).NPU of common food items:o Egg - 100.o Pulses - 65o Meat-80o Milk-75.NPU = Digestibility coefficient x Biological value / 100Digestibility Co-efficient (DC)It is percentage of protein that is absorbed from consumed.DC = Protein absorbed/Proiein Consumed x 100Biological Value (BV)BV of protein is percentage of protein that is utilized by body out of absorbed.BV- Protein utilized/Protein absorbed x 100Protein efficiency ratio = Weight gain per unit protein consumed.Amino acid score = mg of amino acid per gram of protein = mg of same amino acid per g of egg protein.