Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation: effects of freeze–thaw cycles
Nasser Abdullah Al-Habsi, Sara Al-Hadhrami, Habiba Al-Kasbi, Mohammad Shafiur Rahman
Food Science and Nutrition
In this study, the molecular mobility of fish flesh was measured by low field nuclear magnetic resonance (LF-NMR) relaxation. Sardine, tuna and mackerel were frozen at −40 °C and stored for 1 day (24 h); and then these samples were thawed at room temperature (20 °C). The relaxation of water protons in fish flesh was measured for fresh (i.e., before freezing) and multi-cycle freeze–thaw samples (i.e., up to 12 times). Three domains from different pools of protons (i.e., low-mobile, medium-mobile and high-mobile) were identified from the relaxation curve. The T2b (low-mobile), T21 (medium-mobile) and T22 (high-mobile) indicated the proton populations in the protein molecules, strongly bound water molecules, and weakly bound water molecules, respectively. In all cases, the relaxation time (T2b: sardine r = 0.736 and p < 0.01, tuna r = 0.857 and p < 0.001, mackerel r = 0.904 and p < 0.001; and T22: sardine r = 0.956 and p < 0.0001, tuna r = 0.927 and p < 0.0001, mackerel r = 0.890 and p < 0.0001) increased with the freeze–thaw cycles and it reached a nearly constant value after 6 freeze–thaw cycles. The increased relaxation time (i.e., higher mobility) up to 6 freeze–thaw cycles could be due to the increase in proton mobility. However, relaxation time (T21: sardine r = −0.510 and p > 0.05, tuna r = 0.162 and p > 0.5, mackerel r = 0.513 and p > 0.01) showed insignificant change with the increase of freeze–thaw cycles, which indicated minimal change in the medium-mobile protons. The results in this study revealed that the changes in proton mobility in the fish flesh during freeze–thaw cycles could be identified using T2b and T22 relaxation of LF-NMR.
protons
nuclear magnetic resonance spectroscopy
bound water
Fish quality
Freeze–thaw cycle
NMR relaxation
Al-Habsi, N. A., Al-Hadhrami, S., Al-Kasbi, H., & Rahman, M. S. (2017). Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation: effects of freeze–thaw cycles. Fisheries Science, 83(5), 845-851. https://doi.org/10.1007/s12562-017-1114-0
Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation : effects of freeze–thaw cycles. / Al-Habsi, Nasser Abdullah; Al-Hadhrami, Sara; Al-Kasbi, Habiba; Rahman, Mohammad Shafiur.
In: Fisheries Science, Vol. 83, No. 5, 01.09.2017, p. 845-851.
Al-Habsi, NA, Al-Hadhrami, S, Al-Kasbi, H & Rahman, MS 2017, 'Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation: effects of freeze–thaw cycles', Fisheries Science, vol. 83, no. 5, pp. 845-851. https://doi.org/10.1007/s12562-017-1114-0
Al-Habsi NA, Al-Hadhrami S, Al-Kasbi H, Rahman MS. Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation: effects of freeze–thaw cycles. Fisheries Science. 2017 Sep 1;83(5):845-851. https://doi.org/10.1007/s12562-017-1114-0
Al-Habsi, Nasser Abdullah ; Al-Hadhrami, Sara ; Al-Kasbi, Habiba ; Rahman, Mohammad Shafiur. / Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation : effects of freeze–thaw cycles. In: Fisheries Science. 2017 ; Vol. 83, No. 5. pp. 845-851.
@article{d432d08a939442f6ab937253259c6dee,
title = "Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation: effects of freeze–thaw cycles",
abstract = "In this study, the molecular mobility of fish flesh was measured by low field nuclear magnetic resonance (LF-NMR) relaxation. Sardine, tuna and mackerel were frozen at −40 °C and stored for 1 day (24 h); and then these samples were thawed at room temperature (20 °C). The relaxation of water protons in fish flesh was measured for fresh (i.e., before freezing) and multi-cycle freeze–thaw samples (i.e., up to 12 times). Three domains from different pools of protons (i.e., low-mobile, medium-mobile and high-mobile) were identified from the relaxation curve. The T2b (low-mobile), T21 (medium-mobile) and T22 (high-mobile) indicated the proton populations in the protein molecules, strongly bound water molecules, and weakly bound water molecules, respectively. In all cases, the relaxation time (T2b: sardine r = 0.736 and p < 0.01, tuna r = 0.857 and p < 0.001, mackerel r = 0.904 and p < 0.001; and T22: sardine r = 0.956 and p < 0.0001, tuna r = 0.927 and p < 0.0001, mackerel r = 0.890 and p < 0.0001) increased with the freeze–thaw cycles and it reached a nearly constant value after 6 freeze–thaw cycles. The increased relaxation time (i.e., higher mobility) up to 6 freeze–thaw cycles could be due to the increase in proton mobility. However, relaxation time (T21: sardine r = −0.510 and p > 0.05, tuna r = 0.162 and p > 0.5, mackerel r = 0.513 and p > 0.01) showed insignificant change with the increase of freeze–thaw cycles, which indicated minimal change in the medium-mobile protons. The results in this study revealed that the changes in proton mobility in the fish flesh during freeze–thaw cycles could be identified using T2b and T22 relaxation of LF-NMR.",
keywords = "Fish quality, Freeze–thaw cycle, Freezing, Mackerel, NMR relaxation",
author = "Al-Habsi, {Nasser Abdullah} and Sara Al-Hadhrami and Habiba Al-Kasbi and Rahman, {Mohammad Shafiur}",
journal = "Fisheries Science",
publisher = "Springer Japan",
T1 - Molecular mobility of fish flesh measured by low-field nuclear magnetic resonance (LF-NMR) relaxation
T2 - effects of freeze–thaw cycles
AU - Al-Habsi, Nasser Abdullah
AU - Al-Hadhrami, Sara
AU - Al-Kasbi, Habiba
AU - Rahman, Mohammad Shafiur
N2 - In this study, the molecular mobility of fish flesh was measured by low field nuclear magnetic resonance (LF-NMR) relaxation. Sardine, tuna and mackerel were frozen at −40 °C and stored for 1 day (24 h); and then these samples were thawed at room temperature (20 °C). The relaxation of water protons in fish flesh was measured for fresh (i.e., before freezing) and multi-cycle freeze–thaw samples (i.e., up to 12 times). Three domains from different pools of protons (i.e., low-mobile, medium-mobile and high-mobile) were identified from the relaxation curve. The T2b (low-mobile), T21 (medium-mobile) and T22 (high-mobile) indicated the proton populations in the protein molecules, strongly bound water molecules, and weakly bound water molecules, respectively. In all cases, the relaxation time (T2b: sardine r = 0.736 and p < 0.01, tuna r = 0.857 and p < 0.001, mackerel r = 0.904 and p < 0.001; and T22: sardine r = 0.956 and p < 0.0001, tuna r = 0.927 and p < 0.0001, mackerel r = 0.890 and p < 0.0001) increased with the freeze–thaw cycles and it reached a nearly constant value after 6 freeze–thaw cycles. The increased relaxation time (i.e., higher mobility) up to 6 freeze–thaw cycles could be due to the increase in proton mobility. However, relaxation time (T21: sardine r = −0.510 and p > 0.05, tuna r = 0.162 and p > 0.5, mackerel r = 0.513 and p > 0.01) showed insignificant change with the increase of freeze–thaw cycles, which indicated minimal change in the medium-mobile protons. The results in this study revealed that the changes in proton mobility in the fish flesh during freeze–thaw cycles could be identified using T2b and T22 relaxation of LF-NMR.
AB - In this study, the molecular mobility of fish flesh was measured by low field nuclear magnetic resonance (LF-NMR) relaxation. Sardine, tuna and mackerel were frozen at −40 °C and stored for 1 day (24 h); and then these samples were thawed at room temperature (20 °C). The relaxation of water protons in fish flesh was measured for fresh (i.e., before freezing) and multi-cycle freeze–thaw samples (i.e., up to 12 times). Three domains from different pools of protons (i.e., low-mobile, medium-mobile and high-mobile) were identified from the relaxation curve. The T2b (low-mobile), T21 (medium-mobile) and T22 (high-mobile) indicated the proton populations in the protein molecules, strongly bound water molecules, and weakly bound water molecules, respectively. In all cases, the relaxation time (T2b: sardine r = 0.736 and p < 0.01, tuna r = 0.857 and p < 0.001, mackerel r = 0.904 and p < 0.001; and T22: sardine r = 0.956 and p < 0.0001, tuna r = 0.927 and p < 0.0001, mackerel r = 0.890 and p < 0.0001) increased with the freeze–thaw cycles and it reached a nearly constant value after 6 freeze–thaw cycles. The increased relaxation time (i.e., higher mobility) up to 6 freeze–thaw cycles could be due to the increase in proton mobility. However, relaxation time (T21: sardine r = −0.510 and p > 0.05, tuna r = 0.162 and p > 0.5, mackerel r = 0.513 and p > 0.01) showed insignificant change with the increase of freeze–thaw cycles, which indicated minimal change in the medium-mobile protons. The results in this study revealed that the changes in proton mobility in the fish flesh during freeze–thaw cycles could be identified using T2b and T22 relaxation of LF-NMR.
KW - Fish quality
KW - Freeze–thaw cycle
KW - Freezing
KW - Mackerel
KW - NMR relaxation
JO - Fisheries Science
JF - Fisheries Science