Ultrasonic pretreatment of carrot slices: Effects of sonication source on drying kinetics and product quality

Abstract

In this study effects of ultrasonic pretreatment with different sonication sources on drying behavior of carrot slices were evaluated. Fresh carrot slices were pretreated with ultrasonic probe at 65, 75 and 85 W or ultrasonic bath at 10, 20 and 30°C for 3, 5 and 10 min before air drying. Water gain % and solid loss % of pretreated samples were calculated and color values, β-carotene content and rehydration ratios of dried samples were determined. Drying behavior of the pretreated samples was evaluated and the drying data were fitted to thin layer drying models. Constant drying rate period was not observed for the carrot slices; however two definite falling-rate periods having different slopes were obtained. Drying time was significantly reduced (up to 20%) depending on the type of pretreatment. The redness value, total color difference and Chroma values of pretreated and control samples were in the same group (p>0.05). β-carotene content of ultrasonic bath pretreated samples were significantly higher than the samples pretreated with ultrasonic probe and the sample dried without any pretreatment as well (p<0.05). Also rehydration ratios of control samples were found lower than the ultrasound pretreated samples.

Effects of pretreatment and drying methods on the quality and stability of dried sweet potato slices during storage

“…The samples were then removed, drained, lightly blotted with absorbent paper to remove surface water, and then weighed. The rehydration rate (RR) of the sample was calculated using equation (Yilmaz et al, 2019):…”

Drying of Carrot Strips in Indirect Solar Dehydrator with Photovoltaic Cell and Thermal Energy Storage

“…The Midilli-Kucuk model presented the best fit in investigations of thin-layer drying of carrot slices using the infrared dryer [56], by electric resistance convective dryer [17] and with ultrasound pretreatment [57]. On the other hand, for drying carrots in cubes and/or slices [6,42] or carrot pomace [28] employing a convective dryer, the best fit model corresponded to Page's model.…”

Foam stability of cloudy carrot juice: effects of protein sources and foaming conditions

“…The moisture content of carrot or carrot juice is given between 88.9-90.0%, whereas soluble solid content is found between 4.65-12.0 °Bx. Besides the titratable acidity of carrot changes between 0.2-3.0% citric acid or malic acid equivalent, while the pH varies between 4.6-6.2 in the literature (Demir et al, 2007;Liao et al, 2007;Sharma et al, 2009;Schultz et al, 2014;Cozma et al, 2015;Silva et al, 2016;Yilmaz et al, 2019). The total carotenoid content of heat treated carrot juice was found to be 82.35±0.42 μg/g, its antioxidant activity was 62.84±2.82%, and the total phenolic content was 46.36±0.21 mg/g.…”