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Near Infrared Spectroscopy has been used for decades in many industries to provide rapid and precise constituent analysis. Near Infrared Reflectance (NIR) and Near Infrared Transmittance (NIT) are used by analytical OEM’s like Dickey-John and Bruins Instruments to offer a range of analysers to the grain handling, milling, feeds, processing and diary industries. Each instrument within this range has a unique spectral range and sample presentation device for its special application. Different products require diverse sampling and presentation techniques to either increase accuracy and stability of calibrations or the ease of use. This technology offers fast and accurate constituent analysis and lays the foundation for trade and value determination. Near infrared spectroscopy is based on the absorption of infrared radiation by constituents such as protein, oil, starch, carbohydrates and moisture. This absorption is measurable and occurs because such constituents individually resonate at specific frequencies within the infrared spectrum. This resonance will cause interference and thus absorption of that particular spectrum of infrared light. This occurrence is recorded and translated by spectrophotometers. Two of these methods of Near Infrared spectroscopy, NIR and NIT, is used my Dickey-john and Bruins Instruments. The absorbance frequency normally indicates the technology to use but in Ronin GMS’s case NIT is used for whole grains and NIR for powders, pastes and milled products such as flour. With NIT infrared light is transmitted through the whole grain sample and then measured. With NIR the infrared light is reflected from the surface of the sample. The greatest strength of the NIT method is that it is quick, accurate, without intricate sample preparation and therefore limits operator input on the final result. These analysers are ideal for use in the intake offices of silos or production plants that have to obtain numerous sample results within a short period of time. NIR analysers are more suited to millers, processors and quality control laboratories. Sample preparation and presentation are factors that might influence NIR results. Sample preparation has to be methodical in order to ensure that results are accurate and repeatable. Sample grinding or milling has a big impact on the results obtained, therefore the NIR instruments are calibrated with the associated mill or grinder. The main reason for this is that the ground sample particle size distribution can vary between mills produced by a single manufacturer. To obtain good, repeatable results from a NIR instrument, it is necessary to maintain the same particle size distribution every time. Constituents like moisture and oil can also be affected by the heat generated during the milling/grinding process. Thorough training and sample preparation methodologies however promises success and makes NIR the most cost effective analysis solution. Bruins Instruments is the first spectrophotometer manufacturer to offer both NIT and NIR technology in one instrument. This enables the user to explore different technologies for whole grain , pastes, liquids and powders. This technology has been around since the late 1960’s but has been refined over the years. Ronin GMS represents both Dickey-John and Bruins in South Africa and has a team of factory trained technicians to service and maintain these instruments.
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