Modelling oil absorption during post-frying cooling: I: model development and II: solution of the mathematical model, model testing and simulations.

摘要

The quantity of oil absorbed during deep-fat frying contributes to the quality and nutritional value of fried products. Most mathematical models that describe oil uptake in fried product consider the deep frying process in isolation from the post-frying cooling stage. It is claimed that the greatest proportion of oil is absorbed into the crust formed on the product during the cooling stage. The first of two related papers describes the development of a predictive mathematical model to understand the principles behind post-frying cooling oil absorption kinetics and to identify compositional and process factors that influence oil uptake. The model is divided into two sub-models, the first describes the immersion frying period (transient moving front model) and the second describes the post-frying cooling period (pressure driven flow mediated by capillary forces). This mechanistic model is based on measurable physical and thermal properties and process parameters. In the second paper, the mathematical models that describe oil uptake during frying and cooling were solved and tested. The effects of frying conditions on crust thickness and structure and oil uptake during cooling in fried potato chips could be predicted precisely. This model should contribute knowledge of the factors that influence oil absorption in fried products and might help process engineering strategies for the production of healthier fried products.