How does near-infrared spectroscopy work?
Scientific methodology in agriculture allows food producers and manufacturers to make smarter, more informed choices. Testing crops on a scientific level needs a fast, repeatable, and non-invasive method that can test multiple crops for disease and damage.
Near-infrared spectroscopy (NIR) is a method of electromagnetic analysis that has seen use in medicine, industry, and more recently, agriculture. What is this method of measuring crops and how does it work?
What is near-infrared spectroscopy?
NIR uses a specific region of the electromagnetic spectrum—the near-infrared region—directed towards an object. By measuring the light that penetrates or scatters off the object, certain qualities can be ascertained without doing anything to damage or change the sample.
Near-infrared radiation is non-visible light, falling just outside of the visible range of around 400nm to 700nm. It requires spectroscopy equipment to read and analyse the light being reflected, as there’s no way for the naked human eye to detect it otherwise.
Though the term ‘radiation’ is applied to NIR light, it doesn’t harm or irradiate the object it’s directed towards. It’s a perfectly safe and non-invasive way to analyse crops, acting as a kind of x-ray that translates the data it yields rather than producing an image.
NIR spectroscopy holds much promise for crop analysis and health tracking, now and in the future.
How does near-infrared spectroscopy work?
NIR spectroscopy is complex and relies on the power of the equipment used in its measurement. To begin the measurement, near-infrared light is shone onto the object in varying wavelengths and frequencies.
Wavelength and frequency are inversely proportional; a longer wavelength means a lower frequency, and vice versa.
The intensity of the light is measured both before/during transmission and after it has landed on the sample and either been absorbed or scattered. This difference is calculated and applied to the bonds between molecules present in the sample.
Different bonds absorb the energy at different wavelengths and frequencies, which is why the spectrometer transmits the light in a range of these differing wavelengths and frequencies. The degrees of absorption and reflectance form the basis of the results that can be used to determine chemical composition and concentration.
Of course, most people can’t be expected to calculate such complex scientific technicalities. For this reason, NIR spectrometers like the kind used on-site or in the lab for agriculture are programmed to do most of the work themselves with the exception of some calibration often necessary.
Many spectrometers now feature graphical interfaces and simplified operation, aided by automation to make them as fast and easy to use as possible.
How is near-infrared spectroscopy used in the food industry?
NIR is used in the food industry to measure a wide range of properties without ever damaging a single grain. NIR can be used to determine food content such as protein, carbohydrates, and fat. It can also measure moisture content and determine the presence of certain diseases.
NIR is useful for grain analysis, providing a quick and easy way to measure bulk. This can determine grain quality and profitability in as little as two minutes at a time.
It can also be used to test for biological contaminants such as mycotoxins, which can cause far-reaching damage along the food chain if left undetected.
Combined with other testing methods, NIR spectroscopy helps to form a tight web of quality control and assurance.
Besides testing for health hazards, it can be used to help grade food and sort according to markers of high quality, aiding profitability and allowing the testing of different food growth methods.
What are the benefits of near-infrared spectroscopy?
Near-infrared spectroscopy is a ‘dry’ method of analysis, needing none of the reagents necessary in ‘wet’ testing. This makes it quick and non-technical for the end user, and eliminates the chance of extra contamination occurring as a result of using extra chemicals.
It also means that no samples need to be destroyed in the testing process, so representative samples can be returned to the bulk if proven clean and safe.
NIR spectroscopy yields objective results based on the properties of the sample’s chemical makeup, making it free from human error and wholly reliable. Combined with the speed of a test (between 10 seconds and two minutes) it becomes a highly repeatable method of analysis.
Advancements in technology have also allowed spectrometers to shrink in size without sacrificing power and capability. This means that NIR spectroscopy can be done with modest, tabletop spectrometers that fit in even crowded lab environments.
The benefits of near-infrared spectroscopy lend themselves to agriculture to create safer, healthier, food sources for consumers, and more profitable practices to growers and producers. The barriers to entry are as low as purchasing and maintaining a modern spectrometer.
How can I use near-infrared spectroscopy?
To gain a firm, easy-to-understand introduction to using NIR spectroscopy for your crops, contact Calibre Control. We can familiarise you with the basics of an NIR analyser and give you all the helpful guidance and support necessary to get the most out of it.
Unlock near-infrared spectroscopy by contacting Calibre Control today.