Table 1. — Relative activities of proteolytic enzymes from 

 1-hr hydrolysis at 40 °C and neutral pH.^ 



Manufacturer g^ j^^l^y^^ 



Enzyme and/or concentration activity* 



supplier^ 



Weight % g/g 



Ficin Miles 0.11 900.0 



Ficin EDC 0.21 470.0 



Ficin NBC 0.29 350.0 



Pronase Calbiochem 0.29 345.0 



Pepsin (1:10,000) ..NBC 0.39 260.0 



RhozymeP.F. Cone. Rohm and Haas 0.53 189.0 



Bromelin NBC 0.86 116.0 



Papain Miles 1.12 89.3 



Bacterial proteinase EDC 1.23 81.0 



Trypsin (4 X USP) .NBC 1.45 69.0 



Panol EDC 1.50 67.0 



HT proteolytic Miles 1.50 67.0 



Papain Penick 3.00 33.3 



Bromeliq Miles 4.25 23.6 



Papain NBC 6.10 16.4 



Rhozyme P-11 Rohm and Haas 11.00 9.1 



' Pepsin digestions carried out at pH 2. Activity of 

 pepsin is 1:10,000 based on coagulated egg albumen. 

 Supphers of enzymes are listed in the Appendix. 



• Relative activity is equivalent to the weight ratio (g 

 substrate/g enzyme) at which one-third of the substrate is 

 digested in 1 hr. 



at pH 2 which is optimum for pepsin. Converse- 

 ly, the effectiveness of Rhozyme P-11 and other 

 microbial enzymes in combination with the 

 native enzymes of raw hake is much greater than 

 would be expected on the basis of the results 

 listed in Table 2. 



Autolytic activity of red hake. — Native pro- 

 teolytic enzymes play a major role in the hy- 

 drolysis of raw, whole red hake and as noted 

 above modify somewhat the apparent relative 

 activities of various added enzymes. In an early 

 phase of the biological program, whole fish slur- 

 ries were cooked prior to digestion as a standard 

 control measure. There was a significant auto- 

 digestion during heat up of the slurry before 

 native enzymes were inactivated. It was found, 

 however, that effective solubilization of pre- 

 cooked fish could not be achieved unless an ex- 

 cessive amount of commercial enzyme was ad- 

 ded. Soluble solids were obtained from cooked 

 fish in lower yields with low concentrations of 

 tryptophan and phenylalanine and in many cases 

 a complete absence of tyrosine. For this reason, 

 raw fish were chosen as the standard starting 

 material for enzymatic hydrolyses. 



Table 2. — Relative activities of enzymes for 24-hr hydrolysis of fish protein at near op- 

 timum pH and temperature. 



Manufacture specified Test 



Enzyme* optimum range conditions Relative activity 



pH Temp. pH Temp. 



°C ^C '^ 



Pronase 7-8 50 7.5 50 1,110 



Pepsin rCudahy, 1:10,000) . . 2 40-50 2.0 50 1,000 



Pepsin (NBC, 1:10,000) 2 40-50 2.0 50 770 



Papain (Miles) 6-8 60-70 7.0 65 370 



Panol (EDC) 5-7 50-70 6.0 65 294 



Papain (Wallerstein) 5-6 60-70 6.0 65 294 



Pepsin (Wilson, 1:3,000) ... 2 40-50 2.0 50 286 



Trypsin (Wilson, 1:80) 7-9 40 7.5 40 222 



Pancreatin 7-9 40 7.5 40 222 



Ficin (MUes) 5-8 30-50 6.0 40 200 



Ficin (EDC) 4-9 30-50 6.0 40 167 



Trypsin (NBC, 1:80) 7-9 40 7.5 40 145 



Rhozyme PF Cone. 



(Rohm and Hass, 58.92X) . 5-8.5 40-60 7.0 50 110 



Bromelin (NBC) 4-9 30-60 6.0 50 100 



Bacterial Protease Novo ... 7 .. 7.0 50 78 



HT proteolytic 6-9 50 7.5 50 32.3 



Rhozyme P-11 6-9 40-50 7.5 50 18.9 



Prolase (Wallerstein) 3-8 40 6.0 40 <10 



Bromelin (Miles, 1:10) 4-9 30-60 6.0 50 <10 



Fungal protease (Miles) 4-7.5 30-50 6.0 40 <10 



' Suppliers of enzymes are listed in the Appendix. 



' Relative activity is equivalent to the weight ratio (g substrate/g enzyme) at which 60% 

 of the substrate is solubilized in 24 hr. 



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