AMINO ACID COMPOSITION AND BIOLOGICAL VALUE OF CEREAL PROTEINS

Transcription

1 AMINO ACID COMPOSITION AND BIOLOGICAL VALUE OF CEREAL PROTEINS

2 AMINO ACID COMPOSITION AND BIOLOGICAL VAL VE OF CEREAL PROTEINS Proceedings of the International Association for Cereal Chemistry Symposium on Amino Acid Composition and Biological Value of Cereal Proteins Budapest, Hungary, May 31-June I, 1983 with supplemental invited contributions Edited by RADOMIR LASZTITY and MAT E HID V E G I Department of Biochemistry and Food Technology, Technical University of Budapest, Hungary D. Reidel Publishing Company A MEMBER OF THE KLUWER ACADEMIC PUBLISHERS GROUP Dordrecht / Boston / Lancaster

3 Library of Congress Cataloging in Publication Data International Association for Cereal Chemistry Symposium on Amino Acid Composition and Biological Value of Cereal Proteins (1983: Budapest, Hungary) Amino acid composition and biological value of cereal proteins. Includes index. I. Grain--Congresses. 2. Grain--Composition--Congresses. 3. Amino acids--congresses. 4. Plant proteins Congresses. 5. Cereals as food--congresses. 6. Grain as feed--congresses. I. Lasztity, Radomir. II. Hidvegi, Mate, III. International Association for Cereal Chemistry. IV. Title. SB ' ISBN-13: e-isbn-13: DOl: / Distributors for the U.S.A. and Canada Kluwer Academic Publishers, 190 Old Derby Street, Hungham, MA 02043, U.S.A. Distributors for Albania, Bulgaria, Chinese People's Republic, Cuba, Czechoslovakia, German Democratic Republic, Hungary, Korean People's Republic, Mongolia, Poland, Romania, the U.S.S.R., Vietnam, and Yugoslavia Kultura Hungarian Foreign Trading Company P.O.B. 149 H-1389 Budapest 62, Hungary Distributors for all remaining countries Kluwer Academic Publishers Group, P.O.Box 322, 3300 AH Dordrecht, Holland Joint edition published by D. Reidel Publishing Company, Dordrecht, Holland and Akademiai Kiad6, Budapest, Hungary All Rights Reserved Softcover reprint of the hardcover 18t edition by Akademiai Kiad6, Budapest, Hungary No part of the material protected by this copyright notice may be reproduced or utilized in any form or any means, electronic or mechanical, including photocoying, recording or by any information storage and retrieval system, without written permission from the copyright owner

4 PREFACE Cereals belong to the most important elements in the history of mankind. From the beginning of agriculture, cereals have been by far the most important staple food in the world. Although the cereal consumption decreased to a low level in the developed countries in Europe and North America, in the developing countries over two-thirds of the calorie and protein intake is based on cereals. A substantial quantity of cereals goes indirectly into food via feed to animals. Generally, cereal proteins are classified as proteins of lower biological value because of shortage in lysine and some other essential amino acids. Recent developments in the determination and evaluation of the biological value of proteins and protein mixtures suggest that the oversimplified earlier evaluation of cereal proteins must be reviewed. This book contains the edited proceedings of the International Symposium on "Amino Acid Composition and Biological Value of Cereal Proteins", held in Budapest, Hungary, Hay 31- June 1, 1983, under the sponsorship of the International Association for Cereal Chemistry, Hungarian Scientific Society for Food Industry and Grain Trust, Hungary, with supplemental invited contributions. Scientists (biologist, plant breeders, farmers, chemists, biochemists, engineers, food technologists and nutritionists) from 17 countries presented and reviewed, along with participants from 20 countries, the recent methodology and trends in the determination of the biological value of cereal proteins, v

5 the amino acid composition of cereal proteins and factors influencing the composition and the role of cereal proteins in nutrition and animal feeding. The editors hope that the contribution of well known specialists, working in the different fields related to cereal science and technology, make the Proceedings a valuable source of information for agronomists, food scientists and technologists, nutritionists and decision makers interested in the more effective and widespread use of cereals, cereal proteins and protein preparations, and in the improvement of the biological value of cereal proteins, foods and feeds containing cereal proteins. The editors are particularly grateful to the staff of the Akademiai Kiad6, Budapest, Hungary and D. Reidel Publishing Company, Dordrecht, Holland for the excellent preparation of this book. Professor Radomir Lasztity

6 CONTENTS PREFACE INTRODUCTION v xi PART GENERAL PROBLEMS Lasztity,R. CEREAL PROTEINS - PAST, PRESENT, FUTURE 3 Dako,D.Y. CEREAL UTILIZATION IN WEST AFRICA 27 Karpati,Gy., Saeed,B.M. THE ROLE OF CEREAL AND PLANT PROTEINS IN THE WORLD FOOD SUPPLY 45 Van!~ek,F., Turek,B. AMINO ACID PROBLEM OF CEREALS AT DAILY MEALS 57 Rig6,J. NUTRITIONAL FUNCTIONS OF CEREALS 67 Hackler,L.R. CEREAL PROTEINS IN HUMAN NUTRITION 81 PART 2 METHODOLOGY OF PROTEIN QUALITY EVALUATION Mercer,L.P., Gustafson,J.M., Dodds,S.J. PROTEIN NUTRITIONAL QUALITY: A MODELING APPROACH 107 Walger-Kunze,B. IN VIVO METHODS IN THE EVALUATION OF THE NUTRITIONAL QUALITY OF CEREAL PROTEINS 131 VII

7 Yoshida,A. SPECIFICITY OF AMINO ACIDS FOR NUTRITIONAL EVALU- ATION OF PROTEINS 163 Pellett,P.L. AMINO ACID SCORING SYSTEMS AND THEIR ROLE IN THE ESTIMATION OF THE PROTEIN QUALITY OF CEREALS 183 Hidvegi,M., Bekes,F. MATHEMATICAL MODELING OF PROTEIN NUTRITIONAL QUALITY FROM AMINO ACID COMPOSITION 205 Sosulki,F.W., Sarwar,G. PREDICTION OF PROTEIN NUTRITIVE VALUE OF CEREAL LEGUME BLENDS USING RAT BIOSSAYS AND AMINO ACID SCORES 287 Sarwar,G. DIFFERENCES BETWEEN DIGESTIBILITIES OF PROTEIN AND FIRST LIMITING AMINO ACID IN SOME PLANT PRODUCTS 295 Sarwar,G. AVAILABLE AMINO ACID SCORE: METHOD FOR PROTEIN QUALITY EVALUATION 305 Salg6,A., Ganzler,K., Jecsai,J. SIMPLE ENZYMIC METHODS FOR PREDICTION OF PLANT PROTEIN DIGESTIBILITY 311 Munck,L. OPTIMIZATION OF LYSINE COMPOSITION IN PLANT BREEDING PROGRAMMES AND IN FEED TECHNOLOGY BY THE DYE-BINDING ANALYSIS 325 Barath A., Halasz A. DETERMINATION OF REACTIVE LYSINE BY DYE-BINDING 337 PART 3 CHEMISTRY (AMINO ACID COMPOSITION) AND BIOCHEMISTRY OF CEREAL PROTEINS Golenkov,V.F. COMPARATIVE AMINO ACID COMPOSITION OF PROTEINS OF WHEAT, RYE AND TRITICALE GRAIN 349 Nehez,R. BIOENERGETIC ASPECTS OF AMINO ACID PRODUCTION IN CEREALS 357 Nierle,W. VIEWS ON THE AMINO ACID COMPOSITION OF GRAIN AND THE INFLUENCE OF PROCESSING 371 Torok,E. CONTRIBUTIONS TO THE AMINO ACID COMPOSITION OF PROTEIN FRACTIONS OF WHEAT FLOURS 383 VIII

8 Ka9zkowski,J., Kurowska,E., Moskal,M. ACTION OF SOME PROTEINASES ON WHEAT GLUTEN ISOLATED FROM MATURE AND DEVELOPING KERNELS 391 Nemeth,I. EFFECTS OF FERTILIZERS ON THE AMINO ACID COMPOSI- TION OF CEREAL PROTEIN 399 Orsi,F. EFFECT OF THERMAL PROCESSING ON THE TRYPTOPHAN CONTENT OF BABY FOODS 409 Sharobeem,S.F., Lasztity,R., Hidvegi,M., Salg6,A., Simon-Sarkadi,L. AMINO ACID CONTENT AND IN VITRO PROTEIN QUALITY OF DIFFERENT CORN VARIETIES 421 Baudet,J., Huet,J.-C., Mosse,J. THE AMINO ACID COMPOSITION OF WHEAT GRAIN AS RELATED TO ITS PROTEIN CONTENT 439 PART 4 PROTEIN PREPARATIONS AND CEREALS - AND NUTRITIVE VALUE COMPOSITION TsentC.C. AMINO ACID COMPOSITION AND BIOLOGICAL VALUE OF CEREAL GERMS 453 Cerletti,P., Restani,P. MAIZE GERM PROTEINS, THEIR COMPOSITION, NUTRITIVE VALUE AND FUNCTIONAL PROPERTIES 467 Barber,S., Benedito de Barber,C. CHEMICAL AND BIOLOGICAL DATA OF RICE PROTEINS FOR NUTRITION AND FEEDING 481 Geervani,P. THE INFLUENCE OF HOME PROCESSING ON THE QUALITY OF CEREAL AND MILLET PROTEINS 495 Juhasz,B., Szelenyi-Galantai,M., Jecsai J., Somssich I. COMPARATIVE STUDY OF YIELD AND BIOLOGICAL VALUE OF DIFFERENT CORN VARIETIES 521 Hesser,J.M. WHEAT GLUTEN - A NUTURAL PROTEIN FOR THE FUTURE- TODAY 529 Sarkki,M.-L., Saarinen E.-R. WHEAT PROTEIN PRODUCTS IN NUTRITION 543 IX

9 PART 5 CEREALS IN FOOD AND FEED Kies/C. AMINO ACID BIOAVAILABILITY FROM WHOLE-WHEAT FLOUR BREAD AND EXTRACTED WHEAT FLOUR BREAD BY HUMANS 553 Sosulki/F.W., Fleming,S.E. AMINO ACID INDICES AND RAT BIODATA FOR COMPOSITE FLOUR BREADS FORTIFIED WITH LEGUME AND OILSEED PROTEINS AND LYSINE 561 Lindner,K. FORTIFICATION OF WHEAT FLOUR WITH POTATO PROTEIN 569 Hurwitz,S. CALCULATION OF THE AMINO ACID REQUIREMENTS OF GROWING BIRDS UNDER VARIABLE ENVIRONMENTAL CONDITIONS 577 Fekete,L. REMARKS ON THE IMPORTANCE OF PROTEIN QUALITY IN MIXED FEEDS 595 T6th,A., Herendi,A., Rether,D. THE IMPROVEMENT OF PROTEIN UTILIZATION IN INDUSTRIAL FEEDS AND CEREALS 601 LIST OF CONTRIBUTORS 615 SUBJECT INDEX 619 x

10 I NTRODUCTI ON PROGRESS OF GRAIN CULTIVATION AND RESEARCH IN HUNGARY The temperate climate of Hungary, its soil and its relief ensure favourable conditions for growing cereals. These basic fundamentals together with our economic policy made the dynamic development of our cultivation of grain crops possible. Up to the seventies, the yield of wheat crops increased by more than a factor of 2.5 as compared to the yield in the sixties. In 1982 it was 4400 kg/ha, but the record yield achieved in 1980 was 4760 kg/ha. In the period , Hungary took 8-th place amon9 the wheat-growing countries of the world, or for average yield 6-th place when considering only the countries growing wheat on fields above ha. The considerable increase in the yield of wheat in Hungary is both a result of growing new species with a rich yield, and of the complex mechanization of agriculture. The yield of our most important cultivated plant, corn, was also doubled in the above period of time. Similar results have been achieved for corn. The increase in yields in obviously not a unique phenomenon restricted to Hungary. The change in conditions for growing wheat can be found allover the world, as is shown by the increase of the average yields. In the opinion of geneticists, this is not yet ~he end of this significant increase; the biological potential does promise even greater results. It seems that the yield will be restricted rather by economic arguments than biological considerations. XI

11 Wheat is a very important basic material in food production. In the years preceding the Second World War, about half of the everyday energy requirement of humans was provided by food on flour basis, and about one-third of it by animal nutrients. Nowadays this ratio is reversed, food of flour basis forming about 1/3 of the necessary energy, and animal nutrients 40-45%. This change has occurred in all parts uf the world wellprovided with food. Consequently, there has been a decrease in the usage of grain crops as basic nutrition. A characteristic picture of the state of agriculture in Hungary can be obtained by comparing the total dry residue of agricultural products. It is apparent from this that wheat contributes 25%; a similar amount is provided by corn. The amounts of rough fodder and cereal fodder are also significant, and the remaining 14% includes all the other main agricultural products, such as grapes, fruit, sugar, etc. Thus the subject of today's symposium, "Amino acid composition and biological value of cereal proteins", is very important in Hungary,let alone the fact that in countries not so well-provided with food the major part of food consumed consists of cereal nutrients. That is, in several countries the amount of animal nutrient available is catastrophically low, therefore a very important role is played there by the quality, quantity and distribution of crops. In this light, the role of growing grain crops has another significance. The wheat grown in Hungary serves primarily to satisfy the demands of the population with flour, about 1.6 million tons being used for this purpose. The export is also significant: it forms about 20-25% of the harvest, but the amount used for forage is also very high, being nearly 50%. On studying these numbers we can conclude that Hungary is relatively rich in wheat, and also in other fodders, so that besides the significant extent of wheat export, we also have an indirect export, i.e. the wheat used for feeding is exported in the form of animal nutrients. Statistics show that, in addition to the almost 11 million Hungarian people, we provide nutrients for a further 8-9 million people at a similarly high level. From this it follows that the XII

12 quality and quantity of animal breeding also depends on crop growing. This means that the dynamic development of Hungarian food production is based on the results of crop-growing. In Hungary, there are two famous research institutes dealing with the improvement of wheat: in Martonvasar and in Szeged. In recent decades they have increased the number of species considerably, developing wheat and corn species equivalent to the best foreign species, or even better under domestic conditions, the breed of which are now in progress. As I mentioned earlier, our conditions are favourable for growing high quality wheat, but the increase in demand and the potential for wheat export makes continued research work on the improvement of yield and quality imperative. In Hungary, the agrotechnical branch of agricultural research is very important. It encompasses studies into the effective utility of green crops, the mode of cultivation, various types of dunging, pesticides and irrigation. Of equal importance is the research aimed at the determination of the optimum time for fertilizing, or at clarifying the role of the individual components of fertilizers. In the opinion of researchers, the genetic potential of the new species is utilized only in about 70%. The results of top state farms support this statement convincingly. Further research work is done on increasing the yield and improving the quality, and an ever increasing role in this is played by the state farms. Outstanding results are obtained by there farms. These production systems work with up-to date agrochemistry, special systems of machines, programmed plant protection, and soil conservation, because the value of a given wheat species can only assert itself under optimum agrotechnical conditions. The exploitation of the genetic productivity of the new crop species with a rich yield and a high quality is only possible by the practical application of the most recent scientific results. Numerous Hungarian researchers are also dealing with the nutritive value of crop proteins, as it is demonstrated by the lectures in this symposium. The research work in Hungary concerning cereals is coordinated in two great projects. One of them is the governmental re search programme "Development of XIII

13 grain crop cultivation" in progress at the two above mentioned institutions, and the other one is the branch research programme "Development of products and production of cereal-based food" led by the Research Institute for Milling and Baking Industry. These projects comprehend the whole field of grain crops ftom the improvement to the production of different crop-based foods. In Hungary there are old traditions for the improvement, processing and industrial utilization of wheat; it is enough to refer to the improvement experiments at the end of the last century, or to the appearence of the new, improved species at the beginning of this century, or to the scientific methods developed for studying flour. This last event recently had its 50-th anniversary. However, the Hungarian inventors of the chill-casted crushing cylinder providing the basis for an up-todate milling industry, and of the plansifter could also be mentioned in this context. Hungarian experts also take part in the work of the International Association for Cereal Chemistry. One of the main fields of activity of ICC is concerned with the unifying of experimental methods, i.e. with international standardization. Those who keep track of the Hungarian standards find numerous signs of well grounded investigations based on international comparisons of the different workshops of ICC. The forums of ICC are suitable for lectures of international standard delivered by Hungarian experts in cereals, today's opportunity also being one of them. The Hungarian researchers take an active part in the workshops of ICC, thereby enriching international scientific life with domestic results. We have also acquired new knowledge by hearing about the identification of wheat species by biochemical procedures, the application of up-to-date instruments such as NIR spectroscopy or atomic absorption spectroscopy in the rapid determination of the composition of crops, etc. In addition to our activity in the workshops, we also take part in documentation, as a result of which valuable pieces of information can be exchanged. In connection with the 50-th anniversary mentioned earlier, in 1978 a working committee of the group dealing with documentation was organized. ICC provides XIV

14 a good opportunity for deepening the connections between researchers of different countries and the exchange of information. The atmosphere of the Commission is determined by the common interest in the investigation of cereals, particularly in their chemistry. The book is a significant landmark in this work, and I hope that the researchers will learn by this more about each others' work; at the same time, they will get an overview of the successful work on cereal research and production in Hungary. Professor Lajos Lenart, General Manager, Grain Trust, Hungary xv