Effect of Different Cooking Methods on Proton Dynamics and Physicochemical Attributes in Spanish Mackerel Assessed by Low-Field NMR

Abstract

The states of protons within food items are highly related to their physical attributes. In this study, the effect of cooking methods including boiling, steaming, roasting and frying on proton dynamics, physicochemical parameters and microstructure of Spanish mackerel was assessed by low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) techniques. The treatment of cooking resulted in a significant reduction of proton mobility and declined freedom of protons. The state changes of protons can be monitored easily in an intuitive and non-destructive manner during various cooking process. The treatments of boiling, steaming, roasting and frying resulted in different cooking loss and similar water-holding capability. A significant increase of total carbonyl content and thiobarbituric acid reactive substances was found, while a decrease of the values for free thiols and surface hydrophobicity was observed. The analysis of circular dichroism spectroscopy and cryo-scanning electron microscopy showed significant structural change. The correlation coefficients of R cal 2 and R cv 2 from partial least squares (PLS) regression models were more than 0.980, suggesting good correlation between LF-NMR data and hardness, resilience, springiness, chewiness, gumminess, and adhesiveness. Good recoveries and a relatively small coefficient of variation (CV) were obtained from the PLS regression models, indicating good reliability and accuracy in predicting texture parameters for mackerel samples.Foods 2020, 9, 364 2 of 16 and texture characteristics. However, it is a challenge to characterize the water dynamics, protein denaturation and lipid oxidation during various thermal processes of Spanish mackerel. Therefore, it is vital to determine the effect of different cooking methods on protein and lipid state changes in Spanish mackerel. The states of protons from water, proteins, lipid and polysaccharide are highly related to fish muscle destruction and protein denaturation during thermal processes. Most of the protons coming from the water within the fish meat can be reflected through monitoring relaxation parameters by radio frequency with the low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) techniques [3]. The protons are chemically exchanged back and forth from water to macromolecules in fish meat, so that their transverse component of the magnetization vector can be measured by the spin-to-spin relaxation time (T 2 ). Different food samples have different relaxation time T 2 , and therefore the parameters of T 2 can reflect the change of physical attributes [4]. In addition, the MRI can provide visualized internal information of the food items during processing and storage [5]. At present, the non-destructive LF-NMR and MRI technology has exhibited prominent superiority in assessing food proton change during various food-processing methods, such as rehydration of sea cucumbers [6], drying of surf calm and chicken [7], cooking change of striped snakehead fish, and evalua...

The Hydration Characteristics, Structural Properties and Volatile Profile of Squid (Symplectoteuthis oualaniensis) Mantle Muscle: Impacts of Steaming, Boiling, and Sous Vide Cooking

“…SMM samples treated with BO exhibited more significant changes compared with those treated with another two types of food-processing method, with T 22 peak area (A 22 ) decreased from 4899.75 to 3697.65 ( Table 1 ), consistent with the findings by Sun et al [ 26 ], who also observed significant changes in the peak area (A 22 ) of Spanish mackerel samples during boiling, steaming, roasting, and frying processes. The T 22 water release caused by three cooking methods was in the following order: SV > ST > BO, and among the three types of food processing methods, BO led to a largest water loss.…”

“…A similar result was also reported by Xia et al [ 35 ], who also observed the proton changes using MRI with turbot flesh during boiling, stewing, and frying processes. Similar proton state changes were also observed by Sun et al [ 26 ] during steaming and boiling. The decreased intensity of squid muscle after steaming and boiling examined using MRI suggests that both of them are more drastic cooking methods than sous vide for changing the proton state.…”

“…Magnetic resonance imaging (MRI) analysis was performed as described by Sun et al [ 26 ] with minor modification; the MRI images of samples were acquired on a Niumag Benchtop Pulsed NMR Analyzer PQ001 too. T 1 weighted images was recorded using spin-echo imaging sequence with field of view (FOV) of 100 mm × 100 mm, slice gap (mm) was 1.0, slice width (mm) was 1.0, offset slice (mm) was 26.4, average was 2, phase size was 192, and read size was 256.…”

Effect of Active Coatings Containing Lippa citriodora Kunth. Essential Oil on Bacterial Diversity and Myofibrillar Proteins Degradation in Refrigerated Large Yellow Croaker

“…2, 4-dinitrophenyl hydrazine (DNPH) derivatization method was used to determine the free carbonyl compounds content with the method of Sun et al [35]. Ten millimeters of DNPH was mixed with 1 mL MP solution at 25 • C for 1 h. The mixture was precipitated with 1 mL 20 % trichloroacetic acid (TCA) solution and centrifuged at 2500× g for 15 min at 4 • C. The supernatant was discarded and the precipitate was mixed with 1 mL ethanol: ethyl acetate (1:1, v/v) containing 10 mM HCl.…”

Monitoring Thermal and Non-Thermal Treatments during Processing of Muscle Foods: A Comprehensive Review of Recent Technological Advances

“…PCA applied to the NMR data showed a clear discrimination between the samples according to their cooking method, while weighted images of the MRI scans provided visualizations of internal structural information. In a recent study, low-field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI) techniques were used to study the impact of four cooking methods, including boiling, steaming, roasting, and frying on proton dynamics, physicochemical parameters, and microstructure of Spanish mackerel [181]. T 1 weighted magnetic resonance images were recorded and a significant decrease of MRI intensity for mackerel samples after roasting and frying was observed, demonstrating that these cooking methods were more drastic in changing the proton states than boiling and steaming.…”