Real-time color change monitoring of apple slices using image processing during intermittent microwave convective drying

An intermittent microwave convective drying method combined with a real-time computer vision technique was employed to detect the effect of drying parameters on color properties of apple slices. The experiments were performed at air temperature of 40 to 80℃, air velocities of 1–2 m/s, microwave powers of 200–600 W, and pulse ratios (PRs) of 2–6. Drying rate and drying time varied from 0.014 to 0.000001 min−1 and 27 to 244 min, respectively. The normalized lightness values had ascending and descending parabolic trends with decrease in product moisture content. With descending dimensionless moisture content, redness, yellowness, color change, hue angle, and chroma were enlarged. The normalized redness values changed from −4 to 3. Models relating drying parameters with drying time, drying rate, and lightness were obtained and found to be significant (P < 0.01). Results indicated that microwave power and PRs had more influence on lightness and color change than other parameters.

[1]  P. Kumar,et al.  Continuous flow microwave-assisted processing and aseptic packaging of purple-fleshed sweetpotato purees. , 2008, Journal of food science.

[2]  G. Raghavan,et al.  Kinetics of astaxanthin degradation and color changes of dried shrimp during storage , 2008 .

[3]  Christine Connolly,et al.  Camera‐based colour inspection , 2000 .

[4]  S. Devahastin,et al.  Effects of process parameters on quality changes of shrimp during drying in a jet-spouted bed dryer. , 2007, Journal of food science.

[5]  N. Otsu.  A threshold selection method from gray level histograms , 1979 .

[6]  Sundaram Gunasekaran,et al.  Optimization of pulsed microwave heating , 2007 .

[7]  Rafael C. González,et al.  Local Determination of a Moving Contrast Edge , 1985, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[8]  Zhongli Pan,et al.  EFFECT OF DIPPING TREATMENTS ON COLOR STABILIZATION AND TEXTURE OF APPLE CUBES FOR INFRARED DRY-BLANCHING PROCESS , 2007 .

[9]  Soleiman Hosseinpour,et al.  Continuous real-time monitoring and neural network modeling of apple slices color changes during hot air drying , 2015 .

[10]  M. Omid,et al.  Optimization of intermittent microwave–convective drying using response surface methodology , 2015, Food science & nutrition.

[11]  Siaw Kiang Chou,et al.  A comparative study between intermittent microwave and infrared drying of bioproducts , 2005 .

[12]  Juming Tang,et al.  DIELECTRIC PROPERTIES OF DEHYDRATED APPLES AS AFFECTED BY MOISTURE AND TEMPERATURE , 2002 .

[13]  R. Vadivambal,et al.  Changes in quality of microwave-treated agricultural products—a review , 2007 .

[14]  Raquel Guiné,et al.  Effect of drying treatments on texture and color of vegetables (pumpkin and green pepper) , 2012 .

[15]  Muharrem Keskin,et al.  Intermittent Microwave-convective Air Drying of Oregano , 2009 .

[16]  Elibol Okan,et al.  Drying Properties and Quality Parameters of Dill Dried with Intermittent and Continuous Microwave-convective Air Treatments , 2010 .

[17]  Begoña de Ancos,et al.  Effects of microwave heating on pigment composition and colour of fruit purees , 1999 .

[18]  Soleiman Hosseinpour,et al.  Application of Image Processing to Analyze Shrinkage and Shape Changes of Shrimp Batch during Drying , 2011 .

[19]  C. Contreras,et al.  Influence of microwave application on convective drying: Effects on drying kinetics, and optical and mechanical properties of apple and strawberry , 2008 .

[20]  Mohammad-R. Akbarzadeh-T,et al.  Computer vision systems (CVS) for moisture content estimation in dehydrated shrimp , 2009 .

[21]  Luciano da Fontoura Costa,et al.  Shape Analysis and Classification: Theory and Practice , 2000 .

[22]  Lalit M. Bal,et al.  Kinetics of colour change of bamboo shoot slices during microwave drying , 2011 .

[23]  S. Devahastin,et al.  Application of wavelet transform coupled with artificial neural network for predicting physicochemical properties of osmotically dehydrated pumpkin , 2009 .

[24]  Seyed Mohammad Ali Razavi,et al.  Application of Image Analysis and Artificial Neural Network to Predict Mass Transfer Kinetics and Color Changes of Osmotically Dehydrated Kiwifruit , 2011 .

[25]  Alex Martynenko,et al.  Computer-Vision System for Control of Drying Processes , 2006 .

[26]  W. Mcminn,et al.  Physical and dielectric properties of pharmaceutical powders , 2003 .

[27]  Timothy A. G. Langrish,et al.  Assessment of colour development in dried bananas -measurements and implications for modelling , 2009 .

[28]  Adnan Midilli,et al.  Energy and exergy of potato drying process via cyclone type dryer , 2005 .

[29]  José Blasco,et al.  Machine Vision System for Automatic Quality Grading of Fruit , 2003 .

[30]  José Miguel Aguilera,et al.  An application of image analysis to dehydration of apple discs , 2005 .

[31]  Jun Wang,et al.  Microwave drying characteristics of potato and the effect of different microwave powers on the dried quality of potato , 2004 .

[32]  Soleiman Hosseinpour,et al.  Application of computer vision technique for on-line monitoring of shrimp color changes during drying , 2013 .

[33]  P. Forsline,et al.  Collection, Maintenance, Characterization, and Utilization of Wild Apples of Central Asia , 2010 .

[34]  Can Ertekin,et al.  Drying of eggplant and selection of a suitable thin layer drying model , 2004 .

[35]  G.S.V. Raghavan,et al.  Microwave Finish Drying of Osmotically Dehydrated Cranberries , 2003 .

[36]  Min Zhang,et al.  Effect of Microwave-Assisted Vacuum Frying on the Quality of Potato Chips , 2014 .

[37]  Zacharias B. Maroulis,et al.  The effect of the method of drying on the colour of dehydrated products , 2001 .

[38]  Ashutosh Kumar Singh,et al.  Drying kinetics and quality characteristics of beetroot slices under hot air followed by microwave finish drying , 2014 .

[39]  G. P. Sharma,et al.  Optimization of process parameters for microwave drying of garlic cloves , 2006 .

[40]  Saeid Minaei,et al.  Evaluation of energy consumption in different drying methods , 2011 .

[41]  B. Olmedilla,et al.  The potential for the improvement of carotenoid levels in foods and the likely systemic effects , 2000 .

[42]  Y. Soysal,et al.  Intermittent microwave-convective drying of red pepper: drying kinetics, physical (colour and texture) and sensory quality. , 2009 .

[43]  O. Esturk,et al.  Intermittent and Continuous Microwave-Convective Air-Drying Characteristics of Sage (Salvia officinalis) Leaves , 2012, Food and Bioprocess Technology.

[44]  R. Wrolstad,et al.  EFFECT OF MICROWAVE BLANCHING ON THE COLOR AND COMPOSITION OF STRAWBERRY CONCENTRATE , 1980 .

[45]  Petr Dejmek,et al.  Calibrated color measurements of agricultural foods using image analysis , 2006 .

[46]  P. Perré,et al.  The existence of a first drying stage for potato proved by two independent methods , 2007 .