Efficient Production of Dried Whole Peanut Fruits Based on Infrared Assisted Spouted Bed Drying

Abstract

The present study is designed to evaluate the effect of infrared assisted spouted bed drying (IR-SBD) on the product quality and energy consumption of whole peanut fruits (including peanut kernels and shells). The dehydration of whole peanuts by means of hot-air drying (HD) and infrared drying (ID) were used as the control groups, and the drying characteristics, energy consumption, microstructure, porosity, hardness and fatty acid content were compared. The results showed that, compared to HD and ID, IR-SBD could reduce the drying time by 40% and 33%, respectively, and reduced energy consumption by 66% and 32%, respectively. During the drying process, the structures of both the peanut shells and peanut kernels underwent significant deformation; specifically, the porosity gradually increased gradually. The maximum porosity value was obtained by the samples dried by means of IR-SBD. Under the three drying conditions, the hardness of the peanut shells first decreased and then increased, while the hardness of the peanut kernels showed a trend of first increasing, then decreasing and finally increasing. Compared to the fresh whole peanuts, the IR-SBD dried samples exhibited a 4.07% decrease in fatty acid. This study shows that IR-SBD is a suitable application for the dehydration process of whole peanuts for the purposes of achieving high-efficiency and -quality production in the industrial sector.

Infrared‐assisted spouted bed drying of Chinese yam cubes: effect of constant and variable temperature drying processes on drying behavior, uniformity, and quality attributes

“…Furthermore, the high moisture content in the center of the sample and the low moisture content on the surface produce a moisture concentration gradient that results in a low internal resistance to moisture diffusion. Similar drying behaviors for many agricultural products have also been reported in the literature 12,25 . The highest drying rate was obtained when drying at 70 °C.…”

“…A lab‐scale infrared‐assisted spouted bed dryer developed by our research teams, described by Zhu et al 12 . was employed to perform the drying.…”

“…A lab-scale infrared-assisted spouted bed dryer developed by our research teams, described by Zhu et al 12 was employed to perform the drying. Based on the preliminary experiments, four temperature levels of 40, 50, 60, and 70 °C were selected for constant temperature drying (CTD) of IRSBD.…”

“…The heat loss from IR heating is very low as the IR energy can be radiated directly onto the surface or even inside of the material without the need for a heat transfer medium 9 . Many studies have shown that IRD offers outstanding advantages in terms of energy savings, short drying times, high efficiency and good‐quality products 10‐12 …”

“…9 Many studies have shown that IRD offers outstanding advantages in terms of energy savings, short drying times, high efficiency and good-quality products. [10][11][12] Infrared-assisted spouted bed drying (IRSBD) is a hybrid drying technique that realizes the complementary advantages of SBD and IRD. Uniform drying is provided by the thorough mixing of the materials produced by the jet fluidization while the energy consumption is reduced by the efficient heating assisted with IR.…”