BS EN 15948:2020 pdf free.Cereals – Determination of moisture and protein一Method using Near-Infrared Spectroscopy in whole kernels.
BS EN 15948 The method is based on Near Infrared (NIR) spectroscopy, an indirect, correlative technique to predict the concentration of various constituents in organic samples. Linear or nonlinear regression modelling is used to relate NIR spectra to moisture or protein concentrations determined by officially approved standard methods (e.g. Artificial Neural Network (ANN) regression, Partial Least Squares (PLS) regression).Since NIR analysis is an indirect, correlative technique, the results shall be validated against chemical analysis reference methods. It is important that the reference methods used are officially approved such as the methods described in the EN ISO standards [2], [3], [4] and [5]. The purpose of validation is to determine the standard error of prediction (SEP or SEP(C]) which expresses the accuracy of routine NIR results corrected for the mean difference (bias) between routine NIR and reference method.The standard error of prediction between chemical analysis methods and predictions shall be compared to calibration performances specifications and/or historical  erformances.Performance of the method shall be checked at least annually, against reference methods to secure the constant adequacy of the model with the requirements of this document (see 5.4.3). This performance test shall be made on samples selected from the pool of analysed samples. It could be necessary to resort to some sampling strategy to ensure a balanced sample distribution over the entire  calibration range and to ensure that samples with a commercially important range are covered. At least 20 samples are needed (to expect a normal distribution of variance).For instruments operated in a network and adjusted against a master instrument, it is sufficient to run the performance check of the method on the master instrument. The adjustment (Z.4) respecting the requirements of this clause may be used for the follow-up of the method performance with a least 20 samples according to EN ISO 12099. It is recommended to participate in an internationally accepted proficiency testing scheme (PTS] that includes NIRS predicted results and results generated by following the standards specified in Bibliography. That participation alone cannot be considered sufficient for the follow up of method performance given the reduced number of samples analysed per year. BS EN 15948 pdf download.