Fatty acids like a markers of processed cheese changes during storage.

článek v časopise - ostatní, Jost

angličtina

The changes of fatty acids inclued in sterilized processed cheeses during storage were observed. Cheeses were stored at different conditions for 24 months. The purpose of this work was to study the impact of sterilization heating and storage conditions, such as temperature and time, on the change of fatty acids in sterilized proccesed cheese. Cheeses were stored during four months. Pasteurized processed cheeses were used for comparison. Fatty acids were analysed by gas chromatography after turning into appropriate methylesters.The method using the mixture of solvents was chosen for fat extraction because it gave satisfactory weight yields of fat and good reproducibility. A method using methanolic solution of potassium hydroxide was chosen for a preparation of fatty acids methylesters. This method is simple, fast and the results are comparable with the standardized method using toxic boron trifluoride. All methods gave good linearity, limits of detection and reproducibility, consequently it is suitable for identification and determination of fatty acids. Altogether 25 of fatty acids were identified in samples of pasteurized and sterilized processed cheeses. Myristic, palmitic, stearic and oleic acids represented the most from the quantitative point of view. We can conclude that both the sterilization heating and the storage conditions significantly influence the content of individual fatty acids in cheeses. The contents of fatty acids in cheeses decreased as the consequence of longer time and higher temperature of storage, as well as impact of sterilization heating. This fact can be probably caused by oxidation reactions of cheese fat.

processed cheese, FA, GC

VÍTOVÁ, E.; LOUPANCOVÁ, B.; ŠTOUDKOVÁ, H.; BUŇKA, F.

2008

11. 9. 2008

Chemické listy

Brno

1213-7103

Chemické listy

102

15

Česká republika

714

717

2