Drying Characteristics of Pomegranate Arils Under Near Infrared-Vacuum Conditions

Abstract

Modeling of pomegranate arils drying was carried out under thin layer near‐infrared (NIR)‐vacuum conditions. Drying of the samples was implemented at the absolute pressures of 2, 20, 40 and 60 kPa and drying temperatures of 60, 70, 80 and 90C. Drying behavior of pomegranate arils as well as the effect of drying conditions on moisture loss, effective diffusion, activation energy, shrinkage, color and energy consumption, dried in NIR‐vacuum dryer are discussed in this study. Results showed that the Aghbashlo model had supremacy in prediction of pomegranate arils drying behavior. Effective moisture diffusivity of the samples was estimated in the ranges of 3.07 × 10−10 to 1.14 × 10−9 m2/s. Activation energy were computed between 30.80 and 37.48 kJ/mol. Minimum shrinkage (71.46%) and color difference (16.7%) were achieved at temperature of 60C and absolute pressure of 2 kPa. Energy consumption was estimated in the ranges of 0.206 to 2.072 kWh. Practical Applications Combining NIR with vacuum condition can be a novel method in drying of pomegranate arils. Advantages of this method are high mass transfer coefficients and high quality. NIR radiation energy is absorbed by the surface grain molecules and directly penetrates under the surface into the product. This phenomenon led to the rapid heating of water inside the material. Also, vacuum drying is a potentially useful technique to improve quality as well as nutritional value. Combination NIR with vacuum creates fast and quality method for thin‐layer drying. Monitoring of pomegranate arils can be easily controlled and the aril characteristics can be measured easily. Pomegranate is known as a medicinal plant. Pomegranate arils are used in medicine to cure heart and vascular disease, preventing cancers and blood purification. The dried arils using NIR‐vacuum were preserved for relatively long time and save minerals and vitamins.

A three‐stage microwave‐vacuum, pulsed‐vacuum, and vacuum drying method for lotus seeds

“…It was found that most of the fruit and vegetables experience a relatively limited shrinkage when they were subjected to drying at temperatures from 50 to 70°C. Such as Wang and Brennan (1995) found that drying at 70°C resulted in less shrinkage of potato than drying at 40°C, Alaei and Chayjan (2015) observed that by increasing drying temperature from 70 to 90°C, the shrinkage of pomegranate arils aggravated. This is may be due to the case‐hardening effect that controls the transport of moisture, which ultimately controls material shrinkage.…”

A Comparative Study Between Labeling and Reality: The Case of Phytochemical Composition of Commercial Pomegranate‐Based Products

“…Manufacturers are deeply involved in the development of new Pom‐based products (PomP), because their benefits should led to improved human health (Alaei and Amiri Chayjan ). This is the reason that explains the expanded promotion of Pom products and the increment of the sales from $84500 in 2001 up to $66 million in 2005 in United States (Vázquez‐Araújo and others ).…”

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).…”