Control of powdery contents and mass rates of the extract in the dry substance of barley malt by photoluminescent method

Summary In order to adapt the photoluminescent method for controlling the quality indicators of barley malt, experimental studies were carried out on its grains. The spectral characteristics of excitation and luminescence of products of various powdery contents and the mass rate of the extract in dry substance (extractivity) of the malt are qualitatively similar, though with an increase in submitted parameters, the curves shift upward. The dependences of powdery contents and extractivity on photoluminescence fluxes can be statistically reliably approximated by linear regression models. The developed technologies for photoluminescence control include sample preparation, excitation of luminescence at a wavelength of 424 nm, its registration in the range of 450–600 nm and amplification of the obtained electrical signal. Further, on the basis of previously established dependencies, powdery contents and extractivity of the malt are determined, after which a decision is made concerning further actions towards the products. The photoluminescent properties of malt depend on its powdery contents and extractivity. The spectral method with the excitation of luminescence at a wavelength of 424 nm makes it possible to determine the powdery contents and mass fraction of the extract in the dry substance.