BLUE CRAB STUDY 



Nanne 



Date 



Please evaluate each crab nneat sample for the quality factor listed below, using the appropriate scale. 



Appearance 



Texture 



Overall Taste 



Like extremely 

 Like very much 

 Like moderately 

 Like slightly 

 Neither like nor 



dislike 

 Dislike slightly 

 Dislike moderately 

 Dislike very much 

 Dislike extremely 



Figure 1-4. — Rating sheet for organoleptic evaluation of quality. 



The results of this analysis indicated that it 

 was not necessary to apply statistical correc- 

 tions to the overall taste data. Following this 

 analysis and visual examination of the taste- 

 panel data (Strasser, 1969), it was decided not 

 to apply statistical corrections to the appear- 

 ance, odor, and texture data as well. 



Several different chemical or physical meth- 

 ods have been used or proposed to determine 

 the quality of crab meat from various species. 

 They include determination of ammonia (Bur- 

 nett, 1965; Fernandez-Flores and Salwin, 

 1968) , trimethylamine nitrogen or volatile ba- 

 sic nitrogen (Spinelli, Eklund, and Miyauchi, 

 1964a; Tanikawa, 1959) , volatile reducing sub- 

 stances (Farber and Lerke, 1968), picric acid 

 turbidity (Kurtzman and Sn.vder, 1960), 2- 

 thiobarbituric acid (Anderson and Danielson, 

 1961) , hypoxanthine (Spinelli, Eklund, and Mi- 

 yauchi, 1964b) , physical measurement of shear 

 force (Dassow, McKee, and Nelson, 1962), or 

 drip (Barnett, Nelson, and Dassow, 1967; Col- 



lins and Brown. 1965; Miyauchi, 1963). They 

 were not used in this investigation owing to 

 incomplete information on their suitability for 

 assessing degrees of freshness of thawed blue 

 crab meat (in contrast to fresh meat) or their 

 correlation with sensory evaluation methodol- 

 ogy as recommended by Amerine, Pangborn, 

 and Roessler ( 1965) . A similar conclusion was 

 made by Early (1967). 



Comparison of Freezing Rates 



In order to compare freezing rates, pieces of 

 lump meat of about 5 mm diameter, 20 mm 

 in length and about 1 g in weight were exposed 

 to three different freezing conditions. These 

 conditions were freezing in still air at — 20° F, 

 freezing in circulated nitrogen gas which was 

 kept at — 150° F, and immersion freezing in 

 Freon 12 which had a temperature of — 28° F. 

 The temperature in the center of the piece of 

 crab meat, as measured by fine copper-con- 



