Application of Magnetic Resonance Imaging and Analysis Methods in Food Quality Inspection

Moisture and fat are key factors that influence food quality and flavour. Niumag NMR technology can be applied in food research, quality monitoring, and industrial quality control.

In R&D applications, relaxation signal inversion and fitting can be used to analyse water mobility, hydration characteristics, and water-holding capacity in food matrices—allowing researchers to assess texture and quality. Additionally, magnetic resonance imaging provides visual insights into moisture migration and fat distribution within food samples.

Applications in Food Research:

 

1. Studying Water Mobility: As a low molecular weight solvent, water increases free volume in food systems and enhances molecular motion, potentially reducing product stability. In NMR results, this is reflected by a longer relaxation time.

2. Analysing Water-Holding Capacity: During storage, changes in casein structure can improve water retention. Environmental shifts cause water to migrate from mobile to bound phases, binding tightly with proteins. This leads to reduced free water and altered structural stability. NMR data will show an increase in relaxation time.

3. Hydration Properties: Pectin, a heterogeneous polysaccharide, binds approximately 40% of water molecules within a system. This interaction lowers the T2 value, as bound water restricts macromolecular motion and facilitates proton exchange with surface molecules.

4. Qualitative and Quantitative Analysis: Proton NMR can be used to analyse the composition of lipids in dairy fat, delivering both qualitative and quantitative data.

5. Characterising Dairy Fats: NMR offers a fast evaluation of the physical properties of milk fat, revealing the relative proportions of solid and liquid lipid fractions.

6. Investigating Glass Transition Temperature (Tg): With a temperature-controlled NMR system, relaxation characteristics can be measured at various temperatures. Changes in relaxation times allow estimation of the sample’s glass transition temperature.

NMR Applications in Food Production for Quality Monitoring:

 

1. Determining fat content in products such as instant noodles, potato chips, and pet food.

2. Measuring fat content in biscuits and powdered milk.

3. Assessing fat content in chocolate products.

4. Evaluating fat levels in meat and processed meat products.

5. Measuring oil content in oilseed crops and pre-pressed cakes during oil mill procurement processes…