. Despite the high level of CML in the R2 samples, the concentrationof CML drastically decreased below the limit of detection when GP was added. The estimation of the antioxidant activity of plant phytochemicals added to food cannot be based only on the activities of a particular compound; on account ofinteractions, accompanying compounds should also be taken into account. For example, additive effects were observed in mixtures containing catechin and ascorbic acid or a-tocopherol, whereas in the presence of sulphur dioxide, a synergistic effect was seen (Saucier & Waterhouse, 1999). In this way might arise the strong inhibitory effect of GP added to the oil-formulated muffins, rich in tocopherols. Clearly, the particular ingredients, as well as PCs from GP, play important roles in the reduction of CML levels; however, the influence of all the ingredients on the viscoelastic properties of the product should also be taken into account. Modifying the pore structure in the crumb by adding ingredients might potentially contribute to variations in CML content, through changes in the migration of water and temperature.