Analysis of calibration results for casein determination via indirect method of infrared spectroscopy

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis

Radoslava Jedelská¹  Kristýna Hanušová¹  Václava Genčurová¹  Tao Yong²  Josef Kučera³  Tomáš Kopec³  Oto Hanuš⁴  Jaroslav Kopecký⁴ 

[1] Agriresearch Rapotín, Výzkumníků 267, 788 13 Vikýřovice, Czech Republic;Anhui Agricultural University, Department of Animal Sciences, College of Animal Science and Technology, Changjiang West Rd. 130, 230036 Hefei, P. R. China;Czech Fleckvieh Breeders Association, Horní 28, 591 01 Žďár nad Sázavou, Czech Republic;Research Institute for Cattle Breeding Rapotín, Výzkumníků 267, 788 13 Vikýřovice, Czech Republic;

关键词: cow;    raw milk;    sample;    reference method;    infrared spectroscopy;    nitrogen;   

DOI  :  10.11118/actaun201058050123

来源: DOAJ

【 摘 要 】

Casein measurement is important for cheesemaking and control of dairy cow nutrition. Reference Kjeldahl method is not suitable for routine purposes. Infra-red spectroscopy MIR and MIR-FT use can be a solutin. However, their casein specifity is relatively limited. Aim of the work was to assess the quality of performed calibrations for validation of calibration parameters. A retrospective analysis of MIR and MIR-FT calibrations was performed for estimation of limits their suitable parameters. Mean casein values of reference sample sets varied from 2.49 to 2.7% (2.61 ± 0.155). Mean variation range was 0.561 ± 0.164%. The mean correlation coefficient of calibration (KKK) was 0.974 ± 0.018 (P < 0.001). The mean standard deviation of mean for individual differences (SDID) was 0.03 ± 0.011% (from 0.01 to 0.08). MIR-FT results were slightly better both for calibration and for proficiency testing. The high and low KKKs were higher in the case of accepted calibration as in proficiency testing for MIR-FT and MIR (0.986 > 0.964 and 0.970 > 0.948; 0.982 > 0.947 and 0.947 > 0.911; P < 0.001). The casein number varied from 79.4 to 80.56% in bulk milk samples in three years, its variability was low from 1.4 to 1.5% relatively, which shows on relatively reliable casein analyses by methods MIR and MIR-FT. It does not need to agree fuly for individual milk samples. It is linked more to MIR than MIR-FT. Limits for acceptable calibration parameters were derived: > 0.945 for KKK; 0.048 for SDID and 0.029% for mean difference as maximum.

【 授权许可】

Unknown