Bruker BioSpin NMR Food Screening for Quality Assurance (QA), Quality Control (QC) and R&D

Bruker provides analytical solutions for food testing and quality management. The company’s range of solutions allows farmers, food companies and authorities to deliver fast and reliable quality testing of food or animal feed, in order to help the food processing industry provide better nutrition and health worldwide.

We use our analytical knowledge to maintain quality and safety in all processes, including product development, production, quality control and inspections. Bruker develops and implements a series of analytical systems in food testing that use high field nuclear magnetic resonance (NMR) systems and time-domain TD-NMR benchtop systems.

Time-domain (TD) NMR benchtop systems

Time-domain NMR, also known as pulsed NMR, is a well-known variant of NMR referred to as TD-NMR. Applications for TD-NMR span all kinds of industries, from food, such as solid fat content (SFC) and oil seed analysis, to chemicals and polymers, and finally to the medical and pharmaceutical industry, such as obesity research and magnetic resonance imaging (MRI) contrast agents.

In terms of measurement time and accuracy, the NMR method offers great advantages over classical analytical techniques based on wet chemistry, dilatometry, calorimetry or other spectroscopic techniques. The TD-NMR technique employed by Bruker’s minispec system is the perfect tool for the quantification of one, two or more components in a sample. It discriminates between oil and moisture with very high accuracy. The physical properties of a sample correlate to reference data, whilst the relaxation times characterize the main components of a sample mixture. In addition, sample studies at different temperatures offer further information about characteristic sample features (e.g. SFC determination).

Analysis of fat and water in food by time-domain NMR

TD-NMR is ideal for routine QA/QC and R&D applications as it can be used for:

• Solid fat content (SFC) analysis of fat compositions (ISO, AOCS, IUPAC international standard methods) for the determination of fat melting profiles
• Crystallization behavior studies of fats in foodstuffs such as margarine, halvarines, chocolate, etc.
• Simultaneous determination of oil and moisture in seeds, press cakes and nuts (in accordance with international standard methods: ISO, AOCS, USDA, GIPSA Approval)
• Total fat and moisture content measurement in many different types of food and feed
• Total fat content analysis in chocolate, and chocolate related products
• Simultaneous analysis of total fat content and moisture in chips, milk powder
• Simultaneous determination of fat, water and protein in meat and sausages
• Analysis of droplet size distributions in water-in-oil emulsion, e.g. margarine, halvarine, and in oil-in-water emulsion, e.g. dressing, mayonnaise

Solid fat content (SFC) analysis in fat compositions

Raw materials like fat compositions or blends need to be characterized and controlled according to their melting profiles. SFC determination by TD-NMR analysis is the internationally recognized standard method. It provides a quick, non-destructive and solvent-free measurement. Bruker offers a fully automated solution including tempering procedures, NMR measurement, and determination of the SFC value plus presentation of the melting curve.

minispec sample automation system with 10mm sample tubes

Bruker’s new easy-to-use, cost-effective sample automation system brings automation to routine minispec applications, including complex SFC analysis. Now, thanks to quick sample exchange times that maximize throughput and increase reliability in minispec measurements, productivity is significantly boosted. The minispec sample automation system is available as a standalone accessory to existing minispec systems from the mq and mq-one series, or as a complete new packaged system, enabling all users to benefit from a single supplier solution.

Key advantages include:

• Single supplier solution: minispec and sample automation system both provided by Bruker BioSpin
• Industry renowned service and support by Bruker BioSpin or local representative
• Automatic and accurate control of tempering times, delivering results in strict accordance with SFC international standard methods
• Automation for all other major TD-NMR minispec applications (for 10mm sample tubes) including preparation: sample pre-tempering (heating), barcode reader option

Determination of total fat content in chocolate

This standard method from Bruker can be used to measure total fat content in chocolate and chocolate related products, such as cocoa powder, chocolate liquor and cocoa beans.

• Simple calibration, based on only 3-5 samples
• Calibration based on different amounts of pure cocoa butter, or alternatively on chocolate samples with known fat contents (known via other method, e.g. extraction)
• Reliable and precise

Measurement of oil and moisture content in snack foods

TD-NMR’s reliable and precise method is also ideal for determining oil and moisture content in products such as chips, crisps, nuts, milk powder, dried sausages, dried marzipan and candies – using simple calibration methods based on just 3-5 samples.

Benefits of using NMR for determination of fat and oil content in foodstuffs:

• Fast analysis – measurement within seconds
• Non-destructive method
• The whole sample is measured
• Sample is measured as-is, minimum sample preparation is required
• Measurement is two to three times more reproducible than other techniques
• Measurement is independent of color and surface

Droplet size distribution in food emulsion

Droplet size distribution in food emulsion gives important information about the flavor, spread behavior, stability and shelf life of these products. The minispec provides a non-destructive, user-friendly and cost-effective means of assessing droplet size distribution in water-in-oil emulsions (e.g. margarine, spreads …) and oil-in-water emulsions (e.g. mayonnaise, dressings…).