Study of color kinetics of banana (Musa cavendish) under microwave drying by application of image analysis

Abstract

Microwave drying works on the volumetric heating concept promoted by electromagnetic radiation at 0.915 or 2.450 GHz. In this study, banana ( Musa Cavendish) was taken as the sample and treated under microwave drying. The effect of two process variables, namely slice thickness (2, 3.5, and 5 mm) and microwave power (180 W, 360 W, and 540 W), were studied on drying kinetics and color kinetics. It was observed that the inverse variation relationship exists between drying time and microwave power level while drying time and slice thickness exhibited a direct variation relationship. A Computer Vision System (CVS) was developed to measure the color values of banana in CIELab space using an algorithm written in MATLAB software. Once the color parameters were obtained, they were fitted in First and Zero-order kinetic models. Both models were found to describe the color values adequately. This study concludes that microwave drying is a promising dehydration technique for banana drying that reduces the significant time of drying. Application of CVS is an excellent approach to measure the surface color of banana.

Exergy and Energy Analyses of Microwave Dryer for Cantaloupe Slice and Prediction of Thermodynamic Parameters Using ANN and ANFIS Algorithms

“…In thicker samples, the water must travel a longer distance inside the product to reach the surface, i.e., it takes longer to remove moisture. Such an increment in drying time led to higher energy consumption [41]. Similar reports were also emphasized by researchers elsewhere [29,43,51] for drying kiwi, apple, and onion by microwave dryer, respectively.…”

“…This phenomenon accelerated the vapor motion, guiding the water toward the surface of the samples. For constant microwave power, a rise in the sample thickness will increase the path the moisture has to pass to reach the surface which will eventually enhance the drying time [41]. Other researchers also addressed the effect of the MW power and sample thickness on the drying time of the agricultural products, among which the works by Beigi and Torki [29] on onion slices, Çınkır and Süfer [42] on red meat radish, and Darvishi et al [43] on sweet potato can be mentioned.…”

“…The increase in the energy consumption by changing the power from 180 to 540 W was significant at all thicknesses (p < 0.05); the results indicated that a rise in the MW power and a decrement in the sample thicknesses can decrement the energy consumption. The reason could be the enhanced destruction of the product thickness and accelerated moisture release [39,41]. Moreover, with increasing MW output power, the thermal gradient inside the sample increased, followed by an increment in evaporation rate and a decrease in drying time.…”

Use of ultrasound pre‐treatment before microwave drying of kiwifruits – An optimization approach with response surface methodology

“…Thus, the moisture transfer from inside the sample to the surface and evaporation will be accelerated which results in a shorter drying time (Beigi & Torki, 2021). Similar results were reported by Nagvanshi et al, 2020 for banana and by Darvishi et al (2016) for kiwifruit. Based on Figure 1b, by increasing the microwave power and sonication time the drying time reduced as the mass transfer within the kiwi samples was accelerated.…”

Effect of Thermal and Non-Thermal Technologies on Kinetics and the Main Quality Parameters of Red Bell Pepper Dried with Convective and Microwave–Convective Methods

“…On the other hand, the use of microwave power increases the moisture-absorption capacity of the air, due to the increase in temperature difference between the air and the product, and causes the product to heat up faster and water to evaporate better. As a result, the drying time is reduced [ 19 , 20 ]. Furthermore, the use of higher power for the microwave reduced the drying time.…”