February 15-18, 2009 Washington State Convention Center Seattle ...

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EFFECTS OF POST-PROCESSING STORAGE TIME AND TEMPERATURE ON FISHMEAL
PRODUCED FROM PINK SALMON Oncorhynchus gorbusch BYPRODUCTS
Ted H. Wu* and Peter J. Bechtel
United States Department of Agriculture/Agricultural Research Service,
PO Box 757200
Fairbanks, AK 99775 USA
ted.wu@ars.usda.gov
Alaska’s wild commercial Pacific salmon harvest is over 400,000 metric tons annually. The processing of this catch resulted in
over 110,000 metric tons of byproducts available for production into fish meals and oils. When the initial raw material is not
directly processed the quality of the fish meal is affected. The objective of this study was to examine fish meal produced from
aging raw pink salmon byproducts stored at two temperatures.
Raw pink salmon byproducts were stored at 6 °C from 0-10 days and 15 °C from 0-4 days. Each day a portion of the raw
byproduct was processed into fish meal. Nutritional and chemical analyses were performed on the raw byproducts and
processed meals. The initial starting raw byproducts had values of total volatile base nitrogen (TVB-N) at 36 mg N/ 100g,
histamine at 4.2 mg/kg and thiobarbituric acid reactive substances (TBARS) at 1.9 mg malonaldehyde (MDA)/kg, respectively.
TVB-N values indicated substantial spoilage by day 2 at 15 °C and day 6 at 6 °C
(Fig 1.). Most biogenic amine concentrations of raw byproduct stored at 15 °C increased at day 1 and by day 2 were many
significant differences. There was little temperature dependence for lipid oxidation associated with the respective temperatures.
No great differences in fish meals processed from byproducts were noted in the amino acid profile with storage time or
temperature changes. Biogenic amines in fish meals suggested some changes occurring between day 0 and storage day 3 at
15 °C and storage day 6 at 6 °C. TBARS values in the fish meal at day 2 for both 15 °C and 6 °C showed significant changed
from the starting material.
While chemical indications suggested spoilage of the byproducts with increased storage and temperatures, a lower quality
meal with elevated biogenic amine values and TBARS can still be produced that has a good amino acid profile and essential
minerals.