| Abstract: | Milk fat from 440 butter samples obtained from more than 20 Northern German milk collection areas was extracted and the solid fat content (SFC) determined at 7 temperatures between 0 and 30°C using nuclear magnetic resonance spectrometry. Further, all milk fats were analyzed gas chromatographically for their triglyceride composition. Using a multiple regression analysis triglyceride formulae have been computed which enable the SFC-values to be theoretically calculated at all 7 measuring temperatures. The standard deviations between experimental and theoretical SFC-values at temperatures between 0, 5…, 30°C ranged between 0.88 and 0.38% (r = 0.99990 and 0.99682). Also between the fatty acids C18:1 (oleic acid with isomers), C16 (palmitic acid) resp. C16/C18:1 and the SFC-values measured at 0°C relationships have been established (r = -0.95, 0.93 and 0.93, respectively). Since the expenditure in time necessary for gas chromatographic triglyceride analysis by using simultaneously 2 columns can be reduced to 4 - 5 min and, in addition, extrelut columns allow a very fast isolation of fat from milk for gas chromatographic analyses, rapid characterization of milk fat regarding solid fat contents or also milk fat hardness is feasible by means of triglyceride analysis. Besides the SFC-values a number of other milk fat parameters, such as iodine number, melting point, refraction index etc. can be determined using the same triglyceride analysis. |
