Mar 6, 1990 - of antinutritional factors and their high nutritive value. Pea proteins are, however, deficient in Scontaining amino acids (methionine and cystine) ...
J Sci Food Agric 1990,53, 107-1 10
Amino Acid Composition of Pea (Pisum sativum) Proteins and Protein Profile of Pea Flour Pascal Leterme," Thierry Monmart" and Evelyne Baudart Faculte des Sciences Agronomiques, "Unite de Zootechnie, bunhe de Chimie biologique et organique, Passage des Deport&, 2 B-5800Gembloux, Belgium (Received 20 February 1990; accepted 6 March 1990)
Key words: Pisum sativum, protein profile, amino acids. The influence of coarse milling on the distribution of the protein jiactions in the particles was studied. The profile in proteins was the same for the diferent classes as that for the whole seed. The second part of the work was devoted to the determination of the amino acid composition of the different nitrogenous jiactions. Pea seeds (Pisum sativum L) are mostly used in pig feed because of their low content of antinutritional factors and their high nutritive value. Pea proteins are, however, deficient in Scontaining amino acids (methionine and cystine) and in tryptophan (Mosse et all987). Although pea albumins are richer in essential amino acids (AA) than globulins, no data are available about the AA profile of the insoluble proteins and the non-protein material of pea seed. As the protein fractions do not have the same nutritive value, milling can accentuate this difference in some feeds, such as cereals, because the distribution of the proteins in the seed is heterogeneous and the different particles do not have the same hardness (Taverner et a1 1981). Furthermore, Horvath et a1 (1989)have shown recently that the protein content and some functional properties of pin-milled and airclassified pea flours depend on the particle size distribution. The milling of peas intended for animal feed is coarser, and it is not known if coarse milling modifies the distribution of the protein fractions in the particles. This paper addresses this problem. A sample of peas (cv Solara) was hammermilled through a 3-mm screen with a hammer mill commonly used for pig nutrition. The sieve analysis was performed with a vibratory sieve shaker (Analysette 3, Fritsch, Idar-Obersbein, FRG). The different size fractions were passed through the 0.5-mm screen of a Pulverisette 14 (Fritsch). The procedures of extraction and quantitation of the protein fractions have been described by Gueguen and Barbot (1988).N was analysed according to the Kjeldahl method. The AA compositions were determined using ion-exchange chromatography. Performic acid treatment was used to oxidise methionine and cystine before hydrolysis. Tryptophan was determined by gel filtration 107
J Sci Food Agric 0022-5142/90/$03.500 1990 SCI. Printed in Great Britain
108
P Leterme, T Monmart, E Baudarr
TABLE 1
Results of the sieve analysis (%) of pea particles and their protein fractions ( % total N ) Sieve analysis ( % total)
