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Nutritional evaluation of protein foods

Table of contents (162 p.)

Edited by Peter L. Pellett and Vernon R. Young

Report of working group sponsored by the International Union of Nutritional Sciences and the United Nations University World Hunger Programme

Peter L. Pellett is a member of the department of Food Science and Nutrition, Chenoweth Laboratory, University of Massachusetts, Amherst, Massachusetts, USA.

Vernon R. Young is a member of the Department of Nutrition and Food Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.

The United Nations University, 1980

ISBN 92-808-0129-5

This book is published within the framework and as part of the Sub-programme on Human Nutritional Requirements and Their Fulfilment through Local Diets of the United Nations University's World Hunger Programme. The views expressed are those of the authors and not necessarily those of the United Nations University.

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Part I. Techniques for protein quality evaluation: background and discussion

1. Human protein and amino acid requirements and their relevance to protein quality evaluation

Protein Requirements
Essential Amino Acid Requirements

2. Analytical methods for the determination of nitrogen and amino acids in foods

Protein and Other Nitrogen Components of Foodstuffs
Analyses of Individual Amino Acids in Foods
Estimation of "Available" Amino Acids in Foods 1

3. Chemical and microbiological assays of protein quality

Rationale of Scoring Procedures
Assays Utilizing the Amino Acid Profile Alone or in Combination with Protein Digestibility
Microbiological Assays
Advantages and Drawbacks

4. Evaluation of protein quality in experimental animals

Limitations of Biological Procedures
Evaluation and Choice of Animal Assay Procedures
Methods Based on Changes in Body Weight
Methods Based on Nitrogen Retention
In Vivo Amino Acid Availability in Food and Feedstuffs
Other Assays for Protein Quality
Conclusions: Relevance of Animal Assays to Human Protein Nutrition

5. Clinical methods for the evaluation of protein quality

Criteria for Evaluation

6. Evaluation and choice of assay procedures


7. Research suggestions

Part II. Techniques for protein quality evaluation: methodology

8. Some chemical and microbiological assay procedures for the evaluation of protein quality

A. Recommended Methods for Kjeldahl Techniques in Total Nitrogen Determination
B. Methods for Analysis of Amino Acid Composition of Pure Protein and Protein Foodstuffs
C. Microbiological Assays and Prediction of Protein Efficiency Ratio

9. Some rat and human bioassay procedures

Standardization of Animal Assays
Method for Determination of Protein Efficiency Ratio and Net Protein Ratio*
A Procedure for Determination of Net Protein Utilization Using Rats - Body Nitrogen Technique*
Nitrogen Growth Index in Rats
Procedure for the Estimation of Relative Protein Value in Rats
Procedure for the Estimation of Relative Net Protein Ratio in Rats
Human Studies

10. Statistical considerations

Part III. Glossary of terms used in protein quality evaluation


A. Specific procedures recommended for evaluation of early-generation and more advanced genetic material

General Considerations
Procedures for Chemical and Physical Evaluation - Tests Recommended for Field Laboratories

B. Selected books and other documents

1. Books and Reviews Related to the Evaluation of Protein Quality
2. Some relevant Documents from the Protein- Calorie Advisory Group of the U.N. System and from the World Hunger Programme of the U.N university

Joint UNU-IUNS working group

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