Evaluation of Some Binders and Fat Substitutes in Low-fat Frankfurters

The presence of suppressed and retarded vitrinite reflectance (VR) data introduces a number of difficulties with the prediction of hydrocarbon generation in sedimentary basins. Although the effects of suppression can be removed from measured VR values manually, a kinetic model for suppressed vitrinite maturation would enable both suppressed and unsuppressed VR values to be predicted using thermal histories derived from basin modelling. The evaluation of hydrocarbon generation from suppressed and unsuppressed vitrinite shows that both have similar reaction kinetics. While hydrocarbon generation involves the rupture of the bonds holding volatiles into the vitrinite structure, increases in VR are mainly produced by aromatisation and condensation reactions which take place after volatiles have been expelled. The reactions involved in hydrocarbon generation are different from those responsible for increases in VR, and it is not therefore appropriate to derive kinetic models of vitrinite maturation from laboratory hydrocarbon generation experiments. During the maturation of normal (unsuppressed) vitrinite, the volatiles generated are expelled via the microporous network, and the expulsion efficiency is not limited by the capacity of the microporous network. In hydrogen-rich (suppressed) vitrinites, excess volatiles saturate the microporous network, restricting the further aromatisation and condensation processes within the vitrinite, which results in suppression of VR. Kinetically, this has been modelled by using a variable pre-exponential or " A" value. Two versions of a kinetic model of vitrinite maturation (SMod-1 and SMod-2) have been prepared, based on the amount of suppression predicted by HI-VR calibration models published by Lo (1993) and Samuelsson and Middleton (1998).