Date of Award
Doctor of Philosophy (PhD)
Keith R. Cadwallader
Blue crab (Callinectes sapidus) meat and its processing by-product (CPB) were characterized by instrumental, olfactometric, and sensory techniques to determine the usefulness of CPB as a feed stock for flavor recovery. Instrumental analysis with gas chromatography/mass spectrometry (GC/MS) and gas chromatography/Fourier transformed infrared spectroscopy (GC/FTIR) allowed for the identification of 77 and 80 compounds in claw meat and CPB, respectively. Fifty-five compounds were found common to both samples, suggesting that CPB could be a good source for flavor recovery. Quantitatively, trimethylamine (TMA), alkanes (C15-C17, C19), and indole were high ($>$50ng/g) in claw meat while TMA, carbon disulfide, dimethyltrisulfide, alkanes (C15 and C17), geranylacetone, and 1-dodecanol, among other detected compounds, were high in CPB. A subsequent experiment to define claw meat aroma was carried out by analyzing extracts prepared by atmospheric (A-SDE) and vacuum simultaneous steam distillation-solvent extraction (V-SDE) using gas chromatography/olfactometry (GC/O). After data reduction process, the randomly occurring odorants among the replicated samples were eliminated. Claw meat aroma was defined by seven common odorants, of which five were identified as: 2,3-butanedione, pyrrolidine, (Z)-4-heptenal, 2-acetyl-1-pyrroline, and 3-(methylthio)-propanal. A later experiment involving sensory evaluation confirmed that the aroma of claw meat differed from that of lump meat. The results were in agreement with GC/O findings. Overall results indicated that three odorants were indispensable in crabmeat aroma and could serve as markers for evaluating CPB flavor quality. These markers included pyrrolidine, 2-acetyl-1-pyrrolidine, and 3-(methylthio)-propanal, By monitoring the occurrence and the amount of these markers, it was confirmed that CPB was a good source of flavor recovery. Optimal recovery of these markers could be achieved by heating. Distillation was found to be superior to reflux in recovering the markers.
Chung, Hau Yin, "Instrumental and Sensory Characterization of the Flavor of Blue Crab (Callinectes Sapidus) Meat and Processing By-Product." (1994). LSU Historical Dissertations and Theses. 5719.