Shrimp waste samples were extracted with a variety of
organic solvents. Each fraction was measured for
antioxidant activity by determining the rate of oxidation of
β-carotene-linoleic acid in an emulsion system. An ethanol
extract exhibited the highest antioxidant activity.
Purification of the most active fraction was accomplished by
thin layer chromatography (TLC) and high performance liquid
chromatography (HPLC). Antioxidant activity was not
significantly effected by heating at 100°C for 4 hr or 30
days storage at 4°C.
Purified antioxidant samples were further analyzed by
several spectroscopy methods such as Fourier transformed-infrared
spectroscopy (FT-IR), mass spectrometry and nuclear
magnetic resonance (NMR). The antioxidant was characterized
as an ortho-disubstituted benzene. The content of
antioxidant in shrimp waste was estimated to be 1.80 ppm.
Antioxidant from shrimp waste was extracted and
partially purified by silica gel glass column
chromatography. Two species of rockfish (Sebastolobus
alascanus, Sebastes ruberriumus) were treated with crude
antioxidant solution respectively, while rockfish fillets
(Sebastes alutus) were treated with different concentrations
of antioxidant solutions from the column chromatography.
Higher a* values were found in rockfish samples treated with
antioxidants compared to the control without antioxidant
during iced storage. Furthermore, rockfish fillets treated
with 0.20%, and 0.50% (w/v) antioxidant had lower
2-thiobarbituric acid (TBA) values compared to the control
group of rockfish fillets (Sebastes alutus).
Crude extract (0.50% w/w), and purified antioxidant
(0.10%, 0.20%, and 0.50% w/w) from shrimp waste were applied
to sablefish mince and evaluated for their effectiveness to
inhibit oxidative and hydrolytic rancidity of mince samples.
Treatments with crude extract (0.5%), partially purified
antioxidant (0.2%, 0.5%) had a significantly lower TBA, and
peroxide value (PV) compared to the control group during
refrigerated (4°C) and frozen storage (-20°C). The results
from free fatty acid values suggested that antioxidant from
shrimp waste had no effect on hydrolytic rancidity in
sablefish mince. / Graduation date: 1995
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/27234 |
| Date | 02 August 1994 |
| Creators | Li, Shiao Jing |
| Contributors | Morrissey, Michael T. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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