A study of temperature and sample dimension in the drying of potatoes

It is common knowledge that sample size and drying temperature are two of t he most important factors affecting the drying rate and quality of food. Ho wever, what is less commonly known are how these two factors interact relat ive to each other and their effects on the drying behaviour of potato. Thes e effects were evaluated under controlled drying conditions using a thermog ravimetric analyser. The least-squares method was used to fit a model to th e experimental data and the response variables (slope of the first drying s tage, transition moisture content and slope of the second drying stage) wer e determined systematically. Central composite design was applied for respo nse surface modelling of the factors and regression methodology was used to analyse the results. The results showed that both temperature and sample d imension have significant (P=0.01) effect on drying behaviour of potato. Sa mple dimension significantly affected the transition moisture content, whil st both temperature and sample dimension significantly affected the slopes of the first and second stage of drying.