FISH AND SHELLFISH AS FOOD 



291 



and Oyama have studied the composition of the proteins of the muscle of the 

 Japanese porgy (Pagrus major). Okuda (1919) has determined the cleavage 

 products of both the ordinary flesh and the dark flesh ("chiai"), which occurs in 

 the lateral muscles of the bonito. Okuda, Okimoto, and Yada (1919) have pub- 



Table 71. Products of the Hydrolysis of Muscle Proteins in Per Cent of Ash- 

 AND Moisture-Free Substances. 



Porgy " 

 ( Pagrus 

 major) 



Absent 

 or trace 



1.04 



0.60 



2.17 



8.82 



1.22 



4.72 



1.66 



1.63 

 ? 



2.64 

 5.15 

 2.07 



6.28 

 1.32 

 1.04 



+ 



Halibut '^ 



( Hippo- 



glossus 



hippo- 



glossus ) 



Absent 

 ? 

 0.79 



Bonito *^ ( Katus- 

 wonus pelamis) Cod' 



Chicken" Ordi- 

 nary 

 flesh 



Chiai 

 flesh 



0.68 

 2.28 



0.0 0.0 



2.3 

 2.8 



1.1 

 1.8 



( Gadus 

 morhua ) 



0.0 



or trace 



3.53 



3.88 



Glycine 



Alanine 



Valine 



Valine containing leucine 



Leucine 



Proline 



Phenylalanine 



Aspartic acid 



Glutamic acid 



Serine 



Tyrosine 



Arginine 



Histidine 



Lysine 



Ammonia detennined 



Ammonia isolated 



Tryptophane + + + + + + 



Guanine _ _ _ 0.09 0.12 — 



Adenine _ _ _ 0.04 0.1 — 



Xanthine — — — ? ? — • 



Hypoxanthine — — — 0.08 0.03 — 



Source: 



^ Okuda, Y., and Oyama, K., "Hydrolysis of Fish Muscle," /. Coll. Agr. Tokyo Imp. 

 Univ., 5, 365-372 (1916). 



•^ Osborne, T. B., and Heyl, F. W., "Hydrolysis of Fish Muscle," Am. J. Physiol, 23, 

 81-89 (1908). 



" Okuda, Y., Okimoto, T., and Yada T., "Hydrolysis of the Muscle Proteins of the 

 Whale and the Cod," /. Coll. Agr. Tokyo Imp. Univ., 7, 29-37 ( 1919). 



" Okuda, Y., "Chemistry of 'Chiai' Flesh," /. Coll. Agr. Tokyo Imp. Univ., 7, 1-28 

 (1919). 



lished similar work on the flesh of the cod. Their results are presented in Table 71, 

 together with Osborne and Heyl's (1908) analyses of chicken muscle which 

 may be used for comparison. 



More recently Pottinger and Baldwin (1946) have determined the amount 

 of arginine, histidine, lysine, tryptophane, and cystine in the proteins from the 

 edible portions of a number of fish, shellfish, and Crustacea. Their data, presented 

 in Table 72, show that the proteins of fish, shellfish, and Crustacea are good 



