1.0 



350 400 450 500 550 600 650 700 



WAVE LENGTH, M;J 



Figure 10. --Spectral absorbance measured in 

 transmission of 1:9, 12 N HCl-methanol ex- 

 tract of precooked green tuna flesh (No. 7) . 

 (a) Chloroform extract of HCl-acetone ex- 

 tract, (b) Original HCl-methanol extract . 

 (c) Chloroform extract of (b). 



of this material, however, gave an absorption 

 curve in transmission with peaks at 382, 510, 

 540, and 640 millimicrons (fig. 10, curves a 

 and c). These absorption maxima are compared 

 in table 1 with the peaks reported for some of 

 the products of heme protein disruption that 

 might be identical with the substance found in 

 precooked tuna flesh. 



The coinc. dence of the absorption peaks with 

 those reported by Lewis (1954) for hemin chlo- 

 ride in acetone with excess hydrochloric acid 

 added is particularly striking, and we may con- 

 clude that this substance is present in the extract. 

 We should note, however, that we have failed to 

 find the characteristic hemin chloride platelets 

 on microscopic exannination of these extracts. 



DIRECT EVIDENCE FOR GREEN PIGMENT 



The residues left after treatment of the flesh 

 with acid-acetone and acid-nnethanol were ex- 

 amined by the spectral reflectance technique . 

 The curves obtained were very similar to those 

 reported for acid hematin (Lemberg and Legge 

 1949, p. 173) and "acid stable hemin" (Lewis 

 1954). The comparative values are listed in 

 table 2. 



Of far greater interest was the slight but 

 definite absorption peak that appeared in the red 

 end of the spectrum. This will be noted in 

 figure 1 1 at 625 millimicrons for acid-acetone 

 treated meat (curves a, b, and c), and at 610 

 millimicrons after acid-methanol treatment 

 (curves d and e). The curves show a decrease 

 in this peak height from very green meat (curve 

 a) to less green (curve b) to nornnal (curve c). 



Table 1 . --Characteristic absorption peaks of heme pigment derivatives 



