The Mathematical Model Of Interaction Among The Flora In Row Milk And The Detection Of Milk Quality

Milk is a kind of popular food with high nutritional value and this rich nutrient also provides a good condition for growth and reproduction of the microorganisms. Therefore, it is necessary to analyze the change of bacteria to ensure the quality of milk. This literature contraposes two questions of the interaction among bacteria in raw milk and milk quality detection, and the author establishes the mathematical model of these two problems through the analysis of mechanism and data. The main research work is divided into two parts:The first part is the changing regularity of bacteria, obtained through the ecological evolution process of natural fermentation and rancidity in milk. The factor that varying temperature affects on the growth of milk bacteria is mainly considered in this part. The author has got the functional relationship between the bacteria exchanges in milk and the variation of temperature parameter at various stages by the method of experimental analysis, so as to establish the mathematical model of the interaction among lactic acid bacteria, yeast and nutrients lactose in milk. The differential biological dynamics has been applied in analyzing the model qualitatively, so that we get the fact that lactic acid bacteria and yeat dependent on the changing trends of the temperature to reach a global stability at the non-negative equilibrium point. We also adopt the MATLAB software to numerical simulate the critical temperature that milk starts to deterioration by statistical analysis, to be a referential theory basis for controlling the temperature during raw milk storage.In the second section, on the basis of analysis the measurement methods in the number of bacteria, through different bacteria can be reflected by the different spectra, as well as analysis the principle of detection of bacterial microorganisms and bacterial in milk by near infrared spectroscopy, and considering the measuring time, effect of temperature on the bacteria, on the basis of near infrared spectroscopy detection proposed multi-wave length spectrum to detect the total number of bacteria in milk. Using of the relationship between milk bacterial content and the absorbance of monochromatic light of different wavelengths, to realize the measurements of bacteria in milk on the basis of multi-wave length spectral by multimode optical implementation. Use multiple regression analysis to build the mathematical model of the number of bacteria in milk by determination of a multi-wave length spectral data. Taking into account the important factor of temperature, revealed the relationship between the spectral data and the number of bacteria in milk. So that achieves the purpose of rapid detection.