Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince.
Instrumental measurement of redness loss (decrease in a* value) was evaluated as a tool to follow hemoglobin (Hb)-mediated lipid oxidation in fish muscle. Two washed cod mince model systems were used (prepared at pH 6.5 and 5.5), both fortified with 15 micromol/kg of trout Hb and adjusted to pH 6.5...
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ftucl:oai:eprints.ucl.ac.uk.OAI2:1386821 2023-05-15T16:19:23+02:00 Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. Wetterskog, D Undeland, I 2004-12-01 http://discovery.ucl.ac.uk/1386821/ unknown J Agric Food Chem , 52 (24) pp. 7214-7221. (2004) Animals Color Fish Products Gadus morhua Hemoglobins Hydrogen-Ion Concentration Lipid Peroxidation Muscles Odors Thiobarbituric Acid Reactive Substances Article 2004 ftucl 2016-01-21T23:26:42Z Instrumental measurement of redness loss (decrease in a* value) was evaluated as a tool to follow hemoglobin (Hb)-mediated lipid oxidation in fish muscle. Two washed cod mince model systems were used (prepared at pH 6.5 and 5.5), both fortified with 15 micromol/kg of trout Hb and adjusted to pH 6.5 and 81% moisture. The rate of oxidation was varied through pH alterations (pH 6.1 and 6.9) and addition of an antioxidative cod muscle press juice. During ice storage, TBARS, painty odor, and a* values were followed. In all "oxidizing" samples, a* values correlated well with TBARS and painty odor development; r = -0.95 and -0.77, respectively. In press juice containing samples, the correlation was lower (0.55 for a vs TBARS) because there was a slight a* value decrease even in the absence of measurable lipid oxidation. a* values distinguished between "oxidizing" and stable samples within 1 day, before any lipid oxidation products could be chemically detected. It was confirmed in an aqueous phosphate buffer model system that the redness loss corresponded to a buildup of brownish met-Hb at the expense of oxy- and deoxy-Hb. The a* value data were best used as a lipid oxidation index by calculating the rate of decrease (k value) in the "initial phase" of the redness loss (before accumulation of lipid oxidation products) or in the "differentiation phase" (during the exponential raise in TBARS/painty odor). Calibration to lipid oxidation products must, however, be made for each specific sample type. Washing method, pH, Hb-type, etc., all affected both k values and absolute a* readings. Small yellowness (b*) increases also occurred along with a value losses, possibly the result of polymerized Schiff bases. Article in Journal/Newspaper Gadus morhua University College London: UCL Discovery |
institution |
Open Polar |
collection |
University College London: UCL Discovery |
op_collection_id |
ftucl |
language |
unknown |
topic |
Animals Color Fish Products Gadus morhua Hemoglobins Hydrogen-Ion Concentration Lipid Peroxidation Muscles Odors Thiobarbituric Acid Reactive Substances |
spellingShingle |
Animals Color Fish Products Gadus morhua Hemoglobins Hydrogen-Ion Concentration Lipid Peroxidation Muscles Odors Thiobarbituric Acid Reactive Substances Wetterskog, D Undeland, I Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
topic_facet |
Animals Color Fish Products Gadus morhua Hemoglobins Hydrogen-Ion Concentration Lipid Peroxidation Muscles Odors Thiobarbituric Acid Reactive Substances |
description |
Instrumental measurement of redness loss (decrease in a* value) was evaluated as a tool to follow hemoglobin (Hb)-mediated lipid oxidation in fish muscle. Two washed cod mince model systems were used (prepared at pH 6.5 and 5.5), both fortified with 15 micromol/kg of trout Hb and adjusted to pH 6.5 and 81% moisture. The rate of oxidation was varied through pH alterations (pH 6.1 and 6.9) and addition of an antioxidative cod muscle press juice. During ice storage, TBARS, painty odor, and a* values were followed. In all "oxidizing" samples, a* values correlated well with TBARS and painty odor development; r = -0.95 and -0.77, respectively. In press juice containing samples, the correlation was lower (0.55 for a vs TBARS) because there was a slight a* value decrease even in the absence of measurable lipid oxidation. a* values distinguished between "oxidizing" and stable samples within 1 day, before any lipid oxidation products could be chemically detected. It was confirmed in an aqueous phosphate buffer model system that the redness loss corresponded to a buildup of brownish met-Hb at the expense of oxy- and deoxy-Hb. The a* value data were best used as a lipid oxidation index by calculating the rate of decrease (k value) in the "initial phase" of the redness loss (before accumulation of lipid oxidation products) or in the "differentiation phase" (during the exponential raise in TBARS/painty odor). Calibration to lipid oxidation products must, however, be made for each specific sample type. Washing method, pH, Hb-type, etc., all affected both k values and absolute a* readings. Small yellowness (b*) increases also occurred along with a value losses, possibly the result of polymerized Schiff bases. |
format |
Article in Journal/Newspaper |
author |
Wetterskog, D Undeland, I |
author_facet |
Wetterskog, D Undeland, I |
author_sort |
Wetterskog, D |
title |
Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
title_short |
Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
title_full |
Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
title_fullStr |
Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
title_full_unstemmed |
Loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
title_sort |
loss of redness (a*) as a tool to follow hemoglobin-mediated lipid oxidation in washed cod mince. |
publishDate |
2004 |
url |
http://discovery.ucl.ac.uk/1386821/ |
genre |
Gadus morhua |
genre_facet |
Gadus morhua |
op_source |
J Agric Food Chem , 52 (24) pp. 7214-7221. (2004) |
_version_ |
1766005769729212416 |