Monitoring goat milk quality during pasteurisation and ohmic treatment using UV...

• Author(s): Martins, Rui C. ; Borges, Sónia C. ; Lopes, Vítor V. ; Pereira, Ricardo ; Vicente, A. A.
• Date: 2007
• Persistent ID: http://hdl.handle.net/1822/7483
• Origin: RepositóriUM - Universidade do Minho
• Subject(s): Goat Milk; UV-VIS-SWNIR; Pasteurisation; Ohmic heating
• Document Type: Conference Object
• Language: English

Description

This study evaluates the effectiveness of UV-VIS-SWNIR spectroscopy of goat milk quality degradation during pasteurisation and ohmic heating, being performed on: i) raw goat milk; ii) non-processed milk but passing though pumps, pasteurizer and ohmic heater; and iii) processed milk by pasteurisation and ohmic heating. Spectra were collected by a transmittance probe for UV-VIS and UV-NIR wavelengths. The samples temperature was recorded (18.0 ± 2.0oC) and the probe was always checked for bubble formation or fat residues on lens/mirror system. The integration time was set to 25s and 4s for the collection of UV-VIS and VIS-NIR spectra respectively. Data analysis was performed on each product and for each spectral range independently. The spectra were normalized by its maximum intensity and the corrected for using a robust multiplicative scatter correction algorithm. A principal component analysis was performed to the pre-processed spectra. Results show that UV-VIS-SWNIR reflectance spectroscopy provides a quick and fast assessment of goat milk characteristics and thus it can be used as an indication of the overall product variability, allowing to develop monitoring and control models for both pasteurisation and ohmic heating of goat milk.