This study on Aloe vera gel was conducted to investigate the optimum condition for vacuum concentration in relation to its physicochemical properties and optimum foaming condition of the concentrated products which was used as raw material of foam mat drying. Twenty experiments were conducted for vacuum concentration at different temperature and time combinations. Solutions of numerical optimisation were obtained by using Design-Expert program 7.0 of stat-Ease software for the optimum concentration condition covering the criteria as temperature 55⁰C and time 60 min for concentration are- ascorbic acid 4.095%, total soluble solids 3.6 ºBx, total solids 3.7% , acidity 0.0698 % (as malic acid) and pH 4.97, while the experimental values at temperature 55⁰C... |