Water Dynamics in Composite Aqueous Suspensions of Cellulose Nanocrystals and a Clay Mineral Studied through Magnetic Resonance Relaxometry

AbstractTurbot is a valuable commercial species due to its high nutrient content. Moisture is an important indicator of meat spoilage. This study elucidated distinctive water dynamics in turbot flesh in the freezing–thawing process by nondestructive low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) techniques.T2relaxation spectra were utilized to describe the mobility and content of different types of water. Principal component analysis (PCA) revealed a clear discrimination of various freezing–thawing cycles.T1- andT2-weighted MRI provided further visualization of internal information for turbot flesh. Microscopic examination clearly identified protein denaturation and structural shrinkage. Furthermore, NMR parameters and conventional physicochemical parameters of color, shear force and thiobarbituric acid-reactive substances showed good correlations. To sum up, the study revealed that LF-NMR and MRI are promising techniques to portray the relationship between the water dynamics and changes of turbot quality properties during the freezing–thawing process.

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Surface Nuclear Magnetic Resonance Monitoring Reveals Karst Unsaturated Zone Recharge Dynamics during a Rain Event

Water ◽

10.3390/w12113183 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3183

Author(s):

Naomi Mazzilli ◽

Konstantinos Chalikakis ◽

Simon D. Carrière ◽

Anatoly Legchenko

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Unsaturated Zone ◽

Low Noise ◽

Water Dynamics ◽

Rain Event ◽

Experimental Site ◽

Initial State ◽

Before And After ◽

Nuclear Magnetic

Understanding karst unsaturated zone (UZ) recharge dynamics is crucial for achieving sustainable management of karst hydrosystems. In this paper, we provide the first report of the application of surface nuclear magnetic resonance (SNMR) monitoring of a karst UZ during a typical Mediterranean rain event. This 79 days’ SNMR monitoring is a part of a more than 2 years of SNMR monitoring at the Low Noise Underground Laboratory (LSBB) experimental site located within the Fontaine de Vaucluse karst hydrosystem (southeastern France). We present eight SNMR soundings conducted before and after the rain event that accumulated 168 mm in 5 days. The obtained results demonstrate the applicability and the efficiency of SNMR for investigating infiltration dynamics in karst UZs at the time scale of a few days. We present the SNMR amplitudes that highlight strong signal variations related to water dynamics in the karst UZ. Infiltrated water cause increased SNMR signal during 5 days after the rain event. A significant draining process of the medium starts 15 days after the main event. Finally, after 42 days, the SNMR signal returns close to the initial state.

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Water Dynamics in Turbot (Scophthalmus maximus) Flesh during Baking and Microwave Heating: Nuclear Magnetic Resonance and Magnetic Resonance Imaging Studies

International Journal of Food Engineering ◽

10.1515/ijfe-2017-0028 ◽

2017 ◽

Vol 13 (7) ◽

Cited By ~ 1

Author(s):

Kexin Xia ◽

Haitao Wang ◽

Linlin Huang ◽

Wei Xu ◽

Xiu Zang ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Nuclear Magnetic Resonance ◽

Weight Loss ◽

Magnetic Resonance ◽

Microwave Heating ◽

Shear Force ◽

Protein Denaturation ◽

Water Dynamics ◽

Resonance Imaging ◽

Loss Color

AbstractTurbot is a valuable commercial species because of its high nutrition content. Water redistribution during heating was attributed to temperature-induced protein denaturation and structural shrinkage. Therefore, knowledge about water dynamics provides valuable information related to flesh physical properties (weight loss, color and shear force). Herein, water dynamics in turbot during baking and microwave heating were elucidated by using low field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI). Four distinct water populations with relaxation times of 0.20–0.60 ms, 2.00–6.00 ms, 30.00–60.00 ms, and 250.00–560.00 ms were identified. The dramatic variation of water populations during baking and microwave heating indicated protein denaturation and structural shrinkage, which was further verified by MRI and microscopic examination. Furthermore, good linear correlations were observed between NMR parameters and weight loss, color and shear force. The results revealed that the water mobility and distribution in turbot provided valuable information for quality analysis during baking and microwave heating.

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