SEASONAL-VARIATION OF BUTTERFAT PARAMETER S IN DIFFERENT MILK-COLLECTION AREAS

Throughout 1 year butter samples were collected from 4 West German col lection areas and the butter fat extracted from them. The seasonal tim e course of the iodine numbers, solid fat contents, penetrometer value s, oleic acid-, palmitic acid contents, C16/C18:1 ratios, slipping- an d melting points, refraction indices, C54-, C52-, C54/C52- and C40/C36 values derived from the triglyceride compositions was represented; fu rther, the mean, minimal and maximal values for the different feeding periods were indicated. All parameters mentioned are suited to be used for classifying butter fat hardness and are, hence, also an appropria te measure of the butter spreadability to be expected. Thus, the studi es give a survey of the current influences attributable to stock keepi ng and feeding on butter fat hardness. When comparing these results wi th the iodine numbers, C54- and C52-contents of further 1200 butter fa ts analysed during the past 1 0 years feeding conditions are prevailin g in the 4 underlying collection areas, which are likely to result in a still satisfactory spreadability of butter also in winter under opti mal cream ripening conditions. The studies using the example of 250 bu tter fats have also shown, that triglyceride analysis enables a rapid total characterization of butter fat which includes even important fat ty acids.