Drying Characteristics and Milling Quality Aspects of Paddy Dried With Gas‐fired Infrared

Abstract

Wet paddy was dried under different process conditions applying a laboratory gas‐fired infrared (GIR) dryer. Peak wavelength of infrared emitted and initial moisture content of paddy were varied to study the drying behavior. The available thin‐layer drying models were fitted to the drying data. Then, the modified Page model was chosen with higher coefficient of determination (R2 = 0.9985 − 0.9695) and best‐fitted over other models, based on comparing the values of root mean square deviation (RMSD), average percentage of error (%E) and chi‐square (χ2) between the observed and predicted moisture ratios. Qualities of GIR and temper‐dried wet paddy in terms of head rice yield and whiteness were evaluated. Response surface methodology found that an increase in GIR drying time could increase head rice yield. However, an increase in both GIR drying time and tempering time could decrease the whiteness. The contour overlay graph could then be used for determining the appropriate drying conditions, depending on the industrial or user requirement. PRACTICAL APPLICATIONS Infrared (IR) drying technology has appeared as one of the potential alternatives to the traditional heating methods for obtaining high‐quality dried agro‐products. For long‐grain paddy drying, there is at present a dearth of reports exploring IR drying kinetics, and even in such reports, milling quality was the focus of investigation with respect to appropriate drying process conditions. This study has presented the modeling determination and explanation on milling qualities of paddy dried with gas‐fired infrared dryer. The drying process has provided a guideline on basic information to build a commercial drying system. Finally, these results would have practical applications for maintaining or increasing the milling qualities of paddy in the existing industry.

Fundamentals of Infrared Heating and Its Application in Drying of Food Materials: A Review

“…), paddy (Das et al . ; Laohavanich and Wongpichet ), pomegranate arils (Alaei and Chayjan ), vegetables (Hebber et al . ), cabbage seeds (Zhu et al .…”

“…As a result, the combination of IR radiation and other dying methods can be found more efficient and useful to get improved results. Various researchers have carried out IR drying and combined IR-convective drying for food and agriculture products such as onion (Lewicki et al 1998;Wang 2002;Sharma et al 2005), potato Abe 1998, 1999;Tan et al 2001), pineapple (Tan et al 2001), carrot (Togrul 2006;Mihoubi et al 2009;Wu et al 2014;Doymaz 2015), banana (Nimmol et al 2007;Leonard et al 2008;Swasdisevi et al 2009), apple (Nowak and Lewicki 2005; Witrowa-Rajchert and Rzaca 2009), meat products (Sheridan and Shilton 1999), cashew (Hebber and Rastogi 2001), welsh onion (Mongpraneet et al 2002), industrial tomato products (Celma et al 2009a), seedless grapes (Celma et al 2009b), wet olive husk (Celma et al 2008), citrus press cake (Senevirathne et al 2010), barley Markowski et al 2007), parboiled rice (Bualuang et al 2013), paddy (Das et al 2009;Laohavanich and Wongpichet 2009), pomegranate arils (Alaei and Chayjan 2015), vegetables (Hebber et al 2004), cabbage seeds (Zhu et al 1999), potato chips (Supmoon and Noomhorm 2013) and Murta berries (Puente-Díaz et al 2013).…”

Infrared Radiation: Impact on Physicochemical and Functional Characteristics of Grain Starch

“…In the last decade, studies on IR radiation have proven to alleviate some of the disadvantages of grain processing and have been shown to increase the milling yield with improved functional properties. [5][6][7][8] Considering these advantages, IR mode of thermal processing might emerge as a potential grain processing technology. The IR thermal processing may reduce the obscurity of the grain processing by improving the mechanical, functional as well as nutritional properties.…”

Development of Infrared Radial Radiation Dryer for Paddy

“…For paddy drying by IR, Juckamas Laohvanich and Seree Wongpichet [7] were study behavior of paddy drying process by GAS-FIRED INFRARED (GIR). In the experiment, the tray was vibrated with frequency at 450 cycles/min and the amplitude of vibration was approximately 0.01 m in the vertical direction, conducted using 0.5 kg of wet paddy samples with three replications at four initial moisture contents (M 0 ) of 0.22, 0.27, 0.32 and 0.37 decimal (d.b.).…”