Intelligent modeling and detailed analysis of drying, hydration, thermal, and spectral characteristics for convective drying of chicken breast slices

Chicken breast slices were convectively dried at three different temperatures (60, 70, and 80 degrees C). Drying characteristics were analyzed and the predictive capabilities of artificial neural network (ANN) and semiempirical models were exploited. Low complexity ANN model with 10 hidden layer neurons was developed which provided improved results over eight tested semiempirical models. Influence of drying temperature on water activity, rehydration, shrinkage, color, thermal, and spectroscopic properties of the dried product was investigated. Samples dried at 70 degrees C displayed lower moisture content (7.13% w.b.), water activity (a(w) = 0.45) and color change; while, exhibiting better rehydration potential. Effect of pH on hydration showed that alkaline pH (12.0) facilitated the hydration rate in the samples. Shrinkage in dried samples varied within 20-40% and increased with increase in drying temperature. Thermograms of the dried samples revealed a shift in glass transition temperature from 93 degrees to 140 degrees with an increase in drying temperature, indicating a change in protein structure, which was later confirmed by Fourier transform infrared spectroscopy. Practical Application Data on drying, thermal, and hydration characteristics for chicken slices generated in this study could aid the meat industry in developing faster and more convenient processes. Moreover, the low complexity model engineered in this study will facilitate the development of robust control systems for industrial applications. Salient findings of the study such as: (a) optimum time and temperature combination (i.e., 70 degrees C/5 hr) for drying of chicken breast slices; (b) increased rehydration rate with increase in pH from 3.0 to 12.0; and (c) thermal and spectral characteristics have been reported for dried chicken slices which provides vital information on drying process for improvement in the end product obtained.