“…this research demonstrated how HMMS can be analyzed by 1H NMR, 13C NMR, and 31P NMR techniques, without the need for purification.”
The mixing of two components that have a tendency to separate can be enhanced by emulsifying agents; the emulsifying agents form a film around the dispersed globules and form an emulsion.
Within the food industry, functional emulsifiers (comprising a mixture of monoesters and diesters, including propylene glycol (1,2-propanediol) esters) are widely used to enhance the properties and appearance of final products.
For instance, in the production of ice cream, emulsifiers like this are added to inhibit the recrystallization of ice during freezing, which can also determine the consistency of the ice cream: either to create a foamy texture that can be extruded onto cones or to create a firm texture better suited to shape retention on scooping.
In a similar fashion, lipid emulsifiers can be added to bread dough and cake mixture to increase the final product volume and create consistency in structure for an overall improvement in quality.
The precise concentration and composition of the emulsifier mixture determine the success when it comes to achieving the desired effect. In turn, these components may be impacted by the conditions in which the emulsifier is used or how it is produced. Therefore, it is essential that an emulsifier can be accurately characterized.
In addition, the fatty acid composition of the lipid emulsifier needs to be known because of the nutritional labeling requirements for food products. A range of high-performance analytical techniques, such as high-performance liquid chromatography (HPLC), mass spectroscopy and nuclear magnetic resonance spectroscopy (NMR), can be used to characterize lipid mixtures.
However, as of yet, none of these techniques offer the perfect solution when it comes to analyzing complex lipid emulsifier mixtures. As a result, it is often necessary to use a combination of various methodologies, which can be a wasteful and time-consuming process.
The field has therefore continued to seek a reliable, fast methodology that can easily and fully analyze lipid emulsifiers. One technique that has been central to this search is NMR, as it is a particularly desirable technique, thanks to its minimal necessity of sample preparation and non-destructive analysis.
In the determination of fatty acid composition, NMR has already proved to be a highly effective methodology. Using an optimized 1H NMR methodology, the fatty acid contents of a range of oils, including sunflower, olive and linseed oils, have been determined in under one minute.
Currently, an NMR study has analyzed a complex lipid mixture created from soybean oil by enzymatic alcoholysis reactions. A high monoester mixture of soybean oil (HMMS) was produced by the enzymatic alcoholysis. A Bruker Avance III 500 spectrometer analyzed both the original soybean oil and the HMMS without any purification steps by 1H NMR, 13C NMR, and 31P NMR.
Each of the three named NMR techniques facilitated highly effective quantitative and qualitative analysis of the HMMS complex mixture of emulsifiers.
13C NMR offered a greater degree of spectral dispersion than 1H NMR and thus facilitated better characterization and quantification of mono- and diesters. 31P relative to 13C achieved greater sensitivity, allowing detection of partially esterified glycerols, tocopherol and free fatty acids.
It was shown that the fatty acids within the HMMS were more unsaturated than saturated. Within the HMMS, both polyunsaturated fatty acids as well as monounsaturated fatty acids were detected.
The authors’ overall conclusion was that 31P NMR spectroscopy offered the most useful and practical technique regarding the exact detection and quantification of complex lipid mixture components.
Vafaei N, et al. J Am Oil Chem Soc 2020;97:125–133.
About Bruker BioSpin - NMR, EPR and Imaging
Bruker BioSpin offers the world's most comprehensive range of NMR and EPR spectroscopy and preclinical research tools. Bruker BioSpin develops, manufactures and supplies technology to research establishments, commercial enterprises and multi-national corporations across countless industries and fields of expertise.
Sponsored Content Policy: News-Medical.net publishes articles and related content that may be derived from sources where we have existing commercial relationships, provided such content adds value to the core editorial ethos of News-Medical.Net which is to educate and inform site visitors interested in medical research, science, medical devices and treatments.