The mayonnaise was gently mixed prior to sampling. Thirty
gram portions of mayonnaise were poured into 50 ml polypropylene
centrifuge tubes. According to the procedure of Lagunes-
Galvez, Cuvelier, Ordonnaud, and Berset (2002), the samples were
frozen at 20 C for 24 h and thawed for 2 h at 4 C to break the
emulsion. Two milliliters of water were added and the mixtures
were centrifuged at 4000 rpm for 20 min. The lipid phase
separated from the emulsion residue was stored in closed glass
flasks at 80 C until analysed.