Evaluation of freshwater mussels (Megalonaias gigantea) as a new protein source

Author

Alan Reed Post

Date of Award

12-1982

Degree Type

Dissertation

Degree Name

Doctor of Philosophy

Major

Food Science and Technology

Major Professor

H. O. Jaynes

Committee Members

J. L. Collins, S. L. Melton, C. C. Melton, J. L. Wilson

Abstract

This study was undertaken to evaluate the potential of a commer-cially important species of freshwater mussel (FWM), Megalonaias gigantea, as a high protein food source, and to assess levels of potentially hazardous contaminants in these FWM collected at four sites in the Tennessee and Cumberland rivers. The microbiological examination of FWM showed a total aerobic plate count and total coliform count of 10⁶ cells/g and 10³ cells/g, respectively. Surface river water (SRW) samples showed total aerobic plate counts and total coliform counts of 10³ cells/ml and 10 cells/ml, respectively. Fecal streptococci were absent or present at very low levels in both the FWM and SRW samples. The biological oxygen demand in the SRW indicated significant differ-ences (0.01 level) among locations and ranged from 1.30 to 8.20 mg/1. The chemical oxygen demand indicated significant differences (0.05 level) among locations and ranged from 1.09 to 18.19 mg/1. The proximate composition of freeze-dried flour made from FWM showed 4.09% moisture, 40.71% protein, 3.70% ether extract, 14.77% ash, and 36.74% nitrogen free extract. Seven short chain volatile fatty acids (VFA) identified in FWM flour, ranged from C2 through C7. Acetic and propionic acids predominated amounting to 47.29 and 40.30 mg/100 g of flour, respec-tively. A variety of long chain fatty acids were found in the extracted FWM flour lipids. The two dominant fatty acids were C16:0 and CIS:1, which accounted for 32% of the total fatty acids present. Eight pesticide residues were detected in composite flour locations. These were benzene hexachloride (BHC), heptachlor, heptachlor epoxide, aldrin, dieldrin, pp'DDE, endosulfan-1 and methyl parathion. Only BHC and methyl parathion exceeded federal standards. The FWM had a relatively high content of calcium, manganese and iron. SRW samples showed low concentrations of elements tested. The heavy elements, lead, cadmium and mercury, were found in low concentra-tions in the FWM and SRW samples. Ami-no acid analysis showed that FWM contained at least 17 ami-no acids including the essential amino acids. Glutamic acid, aspartic acid, arginine, lysine, leucine, glycine, valine and alanine were the major acids present. A sensory panel was asked to evaluate a soup made with FWM and record overall acceptability. The product was scored moderately accep-table. From all indications, FWM have the potential of being a new protein source.

Recommended Citation

Post, Alan Reed, "Evaluation of freshwater mussels (Megalonaias gigantea) as a new protein source. " PhD diss., University of Tennessee, 1982.
https://trace.tennessee.edu/utk_graddiss/7835