CHANGES IN TRIACYLGLYCEROLS DURING THE RIPENING OF IDIAZABAL CHEESE

The changes in triglyceride (TG) composition taking place in Idiazabal cheese over a ripening period of 360 days were studied using HPLC. Th e partition numbers (PNs) of TGs ranged between 22 and 53, the groupin gs of TG peaks with PN values of 34, 36, and 38 being the main contrib utors. Polynomial and nonlinear regression analyses were used to fit t he experimental data over the ripening period. Cheese TGs change with ripening time as a function of the chain length and degree of unsatura tion of the constituent fatty acids. The unsaturated TGs increased sli ghtly during the first 3 months of ripening, whereas the saturated TGs decreased slowly during that same period. The short-chain TGs exhibit ed considerable decreases during the first 2 months of ripening, where as the long-chain TGs increased during that time, reaching a maximum a round that same date. The medium-chain TGs increased rapidly during th e first 60 days of ripening and followed a slightly rising trend at th e end of the ripening.