Effect of Hot Air Thin Layer Drying Temperature on Physicochemical and Textural Properties of Dried Horseradish

Abstract

The horseradish (Armoracia rusticana) is an important crop as ingredients for many commercial food products and medicinal uses. However, the horseradish is perishable and preservation of this crop for supplying year-round is necessary. Drying can be used to preserve the horseradish but establishing a suitable drying method and conditions are important for product quality of dried horseradish. The objective of this study was to investigate the effects of hot air-drying temperatures on the physicochemical and textural properties of dried horseradish samples to determine the appropriate hot air-drying conditions. The sliced horseradish samples were dried at 55, 65, 75, 85 and 95 ℃ using a conventional hot air drier. The physicochemical and textural properties of the dried horseradish samples were determined, and the results were compared for different drying temperatures. The ANOVA analysis indicated that the drying temperature affected the physicochemical and textural properties of dried horseradish samples significantly (p<0.05). The experimental results indicated that the moisture content (9.18-6.15%,wb), aw (0.06-0.03), porosity (31.47-12.13%) and rehydration ratio (82.74 -44.47%) decreased and piece density (0.63-0.84 g/mL), hardness (193.63 -298.31N), cohesiveness (1.04-1.32), gumminess (202.13-390.12) and chewiness (635.08-1223.55) of dried horseradish samples increased with the drying temperature. Power law model indicated that the porosity was linearly corelated to the rehydration ratio of dried horseradish samples. The overall results revealed that relatively lower (55-65 ℃) drying temperature range was suitable to keep the quality of the dried horseradish samples. The findings of this study are expected to be helpful for the commercial drying of horseradish samples using hot air-drying method.

Empirical Modeling of Hot Air-Drying Kinetics of Horseradish Dehydration

“…The higher drying temperature decreased the drying time of the samples to reach to an equilibrium moisture content. These results were in the agreement with other studies (Meda et al, 2016;Midilli & Kucuk, 2003;Mitra et al, 2019;Orsat et al, 2006). This study indicated that the constant drying rate periods were 150, 220 and 280 minutes and complete drying times were 300, 350 and 400 minutes (Figure 1) for horseradish samples dried at 85, 70 and 50℃, respectively.…”

“…vitamins, minerals and fibers etc.). Horseradish is a vital crop which is being used as food ingredients for many commercial food products such as sauces and condiments (Mitra, Alim, & Meda, 2019). So, the horseradish has been an important crop in parts of Europe and significant production also exists in the U.S and Canada.…”

“…About 3,500 to 4,000 acres are being cultivated annually in USA (Bratsch, 2009). The primary market for horseradish is for condiment makers (Bratsch, 2009;Mitra et al, 2019). The fruits and vegetables are classified as highly perishable commodities because of their high moisture content (Orsat, Changrue, & Raghavan, 2006).…”

“…A large cold storage area is needed to preserve perishable vegetables. The need of cold environment and large storage area are limiting factors for longer period of horseradish storage (Mitra et al, 2019). In order to overcome this problem and increased the shelf-life of horseradish the horseradish roots can be stored and preserved alternatively for a long time by dehydrating them to a low moisture content which is also desirable for production of many instant and convenient foods formulations.…”

“…have been developed over the years (Mitra et al, 2013;Orsat et al, 2006;Sagar & Suresh Kumar, 2010) and except the freeze-drying technique, applying heat during drying through conduction, convection and radiation are the basic techniques used to force the water to vaporize, while forced air is applied to remove the vapor from the surface of materials to be dried. Considering advantages and disadvantages of different drying methods, hot air dying method is one of the most feasible methods for drying of fruit and vegetables commercially because this method is cheaper compared to some other drying such as freeze drying and this method is efficient for dying of agricultural crops (Mitra et al, 2019). Although there are many researches on drying of different fruits and vegetables to study the feasibility and drying kinetics of dried crops, there was not much literature on dehydration of horseradish.…”