Kinetics of drying of basil leaves (Ocimum basilicum L.) in the infrared

Abstract

The objective of this paper was to model the drying curves of the leaves of basil (Ocimum basilicum L.) in the infrared at temperatures of 50, 60, 70 and 80 ºC and to evaluate the influence of drying temperature on the color of dried leaves. Drying was conducted in infrared dryer with temperature and greenhouse air circulation. Experimental data were fitted to eight mathematical models. The magnitude of the coefficient of determination (R²), the mean relative error (P), the estimated mean error (SE) and chisquare test (χ2) were used to verify the degree of fitness of the models. From the study it was concluded that: a) the behavior of the drying curves of basil leaves was similar to most agricultural products, the drying times in the infrared were less than the drying times in an oven with air circulation, b) the mathematical drying model proposed by Midilli et al. (2002) was the one which best adjusted to the experimental data, c) the diffusion coefficient ranged from 9.10 x 10-12 to 2.92 x 10-11 m² s-1 and d) the color of the samples was highly influenced by drying, becoming darker due to loss of chlorophyll with increasing temperature.

Effect of Dehydration Methods on Okra Chemical and Physical Composition

“…Consequently, chlorophyll degradation occurs and this process varies also according to pH and variations of temperature, light and oxygen in the sample (Bohn & Walczyk, 2004). Similar behavior was reported by Reis et al (2012) in the convective drying of basil (Ocimum basilicum L.) leaves, which caused degradation of chlorophylls with the increase in drying temperature.…”

Pequi pulp (Caryocar brasiliense Cambess): Drying kinetics and thermodynamic properties

“…Figure 1 shows that constant k of the model of Midilli increases in absolute values with increasing temperature, since higher temperatures lead to higher drying rates; however, the other coefficients of the model of Midilli (a, n and b) did not show a clear trend as a function of drying temperatures. Reis et al (2012) also reported increased k constant with increasing temperature when drying basil leaves.…”

Drying Kinetics of Niger Seeds

“…Such models include the Midilli, Page, Thompson, Verma, Henderson and Pabis, logarithmic, two-term, two-term exponential, Newton, Wang and Singh, diffusion approximation, and Valcam models (Mohapatra & Rao, 2005;Kashaninejad et al, 2007;Goneli et al, 2009;Corrêa et al, 2010;Resende et al, 2011;Prates et al, 2012;Reis et al, 2012;Siqueira et al, 2012a;Siqueira et al, 2012b;Isquierdo et al, 2013;Santos et al, 2013). Fernanda P. da Silva, Valdiney C. Siqueira, Guilherme A. Quinzani, et al Eng.…”