By: Harsha Pore *
Consumers nowadays are more inclined towards high-quality processed foods because they find these foods more convenient, less prone to spoilage, more portable, nutritionally efficient, and more consistent in quality levels than fresh foods. These demands have forced the food producers to develop and reformulate new and standard types of foods such as: reduced-calorie foods; or all-natural food products. Also, the rapid awareness about food authenticity and food quality around the world is contributing majorly in creating safe food for consumers. Safety, nutrition, and sensory attributes are important for both fresh and processed food products. In recent years, consumers have been placing more emphasis on wellness as well as on food safety. They are interested in authentic foods and beverages that deliver healthy nutrients and bioactive compounds. To develop high-quality safe foods and designing nutrition-based approaches that promote human health, the food scientists and nutritionists need robust and non-destructive analytical methods that can effectively analyse the composition and measure the physicochemical properties of food matrices. The mechanical or chemical methods which were used traditionally for assessment procedures are destructive and time-consuming. These methods nowadays are not able to respond to the contemporary food industry demands. Over the last few decades, new technologies like image-processing techniques have emerged for food quality evaluations such as: optical imaging; ultrasound; computed tomography (CT); nuclear magnetic resonance (NMR) imaging; and thermal imaging. The NMR or magnetic resonance imaging (MRI) was first discovered in the 1950s and it has been developed as a major analytical methodology since then. This article will give an introduction about Nuclear Magnetic Resonance technology and how successful this technology is in making its place in the food industry.
Nuclear Magnetic Resonance (NMR)
Nuclear magnetic resonance (NMR) is one of the most powerful analytical tools to identify organic and bio-organic substances and to elucidate their chemical structures. This is a robust technology which is used to rapidly analyse mixtures at the molecular level without requiring any separation and/or purification steps.
Applications in the Food Industry
NMR technology is one of the most versatile analytical techniques. This has long been recognised as a useful technology for food scientists. The application of nuclear magnetic resonance technology for the analysis and quality control of foods has shown a great development over the last few years. This can be applied to any type of material whether it is liquid and/or solid. It is used for the analysis of several foods such as: beverages; oils and lipids; vegetables; meat; and dairy products.
This technique is also used for examining the textures of foods without using any marker compounds or physical incursion. The data obtained from NMR can also be utilised for various applications such as: to understand the mechanism of processes (chemical or enzymatic reactions involved during the production); and to supplement quality and process controls during the production process.
NMR is Still an Underutilised Technology
Despite the tremendous advantages of NMR technology, it is still an underutilised technology in the area. This has various limitations such as: high cost; lower sensitivity compared to other techniques; and the lack of NMR knowledge among food scientists.
The NMR applications in food processing are not very popular at the industrial/farm levels mainly due to the higher cost and the technical limitations of super conducted magnets.
The development of portable permanent magnets, operating in Larmor frequencies higher than 100 MHz, may lead to increased applications in this area. However, recent advances in NMR instrumentation combined with more user-friendly software for data acquisition and processing, have facilitated the popularity of NMR among food scientists and significantly increased its contributions in the field. The advances in spectral databases for food components will be an important next step for future food applications involving NMR analysis. This requires close collaboration between NMR scientists, academicians, and the food industry.
The principles and applications presented in this article strongly emphasise the goals, scope, and capabilities of NMR in the food industry. Because NMR can provide information about the composition and structure of several classes of foods in a rapid and non-invasive way, it can be an invaluable tool for quality control, authentication, and food safety purposes. Similarly, NMR could be a very powerful tool for understanding the food is metabolism and assessing the impact of various foods and nutrients on human health.
* Food Technologist, FMCG, Fingerlix, Mumbai, Maharashtra, India