This method describes how the protein content in malting barley is determined. Protein plays an essential role in the production of beer. Barley with a high protein content is more difficult to malt and leads to greater malting losses. Barley with a low amount of protein is preferable, especially for beers light in color. As the protein content of barley increases, its extract content decreases.
The nitrogen/raw protein content of barley intended for the production of brewing malt must be determined in advance.
In contrast to the NIR method, the more recently developed NIT method measures the light passing through the samples. This technique requires no pretreatment of the samples, thus eliminating a major source of error. The large sample size, approx. 500 g, makes highly precise measurements possible. Measurements are usually made in the wavelength range of 570−1100 nm.
Calibration and the calculations for determining the amounts of the various constituents are both performed in the same way as in the NIR method. Special software for personal computers can be employed to create the calibration data, which uses the data structure generated and stored in the NIT device as a basis for the calculations. The advantages offered by this method are the rapidity of the analysis (approx. 45 s per sample) and the absence of chemicals.