Evaluation of Organic Acids and Ultrasound as Pretreatment in Convective Drying Kinetics and Quality Parameters of Pumpkin.

There is a growing interest in the food industry in new drying technologies that reduce the time required for dehydration, combined with low energy consumption, low environmental impact, and maintenance of the overall quality of the product. This work investigated convective drying of pumpkin with and without ultrasound-organic (citric or acetic) acid pretreatment for different durations (10, 20, and 30 min). Drying was carried out at 60 °C, and the Wang and Singh model had the best fit for the experimental data.

Convective drying of mango enriched with phenolic compounds from grape residue flour under different impregnation methods.

This work evaluated the effect of convective drying of mango impregnated with grape residue flour polyphenols under different vacuum impregnation methods with or without performing osmotic treatment and ultrasound on the global quality of dried mango in relation to chemical, microbiological and sensory aspects. Higher retention of carotenoids, phenolic compounds, and ascorbic acid was obtained with shorter drying times and lower oxygen exposure. Impregnated dried samples submitted to ultrasound-assisted vacuum impregnation showed a higher drying rate, greater retention of carotenoids (6.

Effect of Ethanol and Ultrasound Pretreatments on Pineapple Convective Drying.

Research Background: Drying represents a viable unit operation for the preservation of food. Convective drying is the most used method for plant materials. However, it can result in negative changes in food nutrient composition, and other quality parameters, besides requiring high energy consumption.

Effect of ethanol pretreatment on melon convective drying.

The aim of this study was to evaluate the effectiveness of the use of ethanol, ultrasound and/or vacuum as a pretreatment to melon drying. Eight types of pretreatments were performed in which samples were immersed in ethanol solutions with different concentrations (50% and 100%) using four treatment conditions: immersion, immersion with ultrasound (US), with vacuum (VC) and with ultrasound and vacuum (USVC). Drying was performed at 60 °C and five different semi-theoretical drying mathematical models were examined to characterize the drying curves, and quality analyses were carried out.