Xiaobing Xiong

Bio: Xiaobing Xiong is an academic researcher from Purdue University. The author has contributed to research in topics: Low-density polyethylene & Ultimate tensile strength. The author has an hindex of 1, co-authored 1 publications receiving 94 citations.

Moisture Diffusivity Data Compilation in Foodstuffs

Abstract: A review of the recently reported moisture diffusivity experimental data in food materials is presented in this work Values are classified and analysed statistically to reveal the influences of temperature and moisture content Empirical models relating moisture diffusivity with the above variables, along with relevant graphs for various materials, are included Other factors affecting moisture diffusivity prediction are also discussed

Sorption isotherms, GAB parameters and isosteric heat of sorption

Abstract: The diffusion-sorption drying model has been developed as a physics-based way to model the decreasing drying rate at low moisture contents. This new model is founded on the existence of different classes of water: free and bound water. The transition between these classes and the corresponding thermodynamics form distinct components of the drying model. This paper shows that the characteristics of the different classes of water and of the transition between them can be deduced from the GAB sorption isotherm. The parameters in the GAB sorption isotherm support the theory of localised sorption, establishing the existence of different classes of water. Moreover, the sorption mechanism retrieved from the GAB parameters is in accordance with the sorption mechanism, which is obtained from the moisture dependence of the net isosteric heat of sorption. This holds for experimental sorption data of corn and starch as well as for literature data on five vegetables and four fortified cassava products. An extremum in the net isosteric heat of sorption coincides with the transition between bound and free water, and the partition moisture content corresponds with the monolayer value derived from the GAB equation. This confirms that the GAB monolayer value can be chosen as model boundary between bound and free water. Moreover, it reveals that this method can be developed into a technique to estimate the bound water content in foods.

Hot air and sun drying of grape leather

Abstract: Abstract Pestil, a well known fruit leather in Turkey, was prepared from boiled grape juice and starch mixture by using traditional technique. Drying of pestil was carried out by hot air drying and sun drying. The factors investigated in hot air drying were air temperature (55, 65 and 75 °C), sample thickness (S1=0.71, S2=1.53, S3=2.20 and S 4 =2.86 mm ) and air velocity (V1=0.86, V2=1.27 and V 3 =1.82 m / s ). The effects of drying time, temperature and slab thickness on moisture content of pestil during drying were significant (P 0.05). Depending on sample thickness and air temperature, the drying time ranged between 50–140 min to achieve the commercial moisture content of pestil ( 0.12 kg H 2 O / kg DS ) in air drying. Whereas, sun drying took 180–1500 min. Almost all samples dried in the falling rate period, except S2, S3, S4 of sun drying and S4 at 55 °C. The latter had a short (negligible) constant rate period. Effective moisture diffusivity values were estimated from Fick's diffusion model. These values were between 3.00–37.6×10 −11 m 2 / s for hot air drying and 1.93–9.16×10 −11 m 2 / s for sun drying. Activation energy value of water diffusion was calculated using an Arrhenius-type equation. The estimated values were 21.7, 16.5, 12.0 and 10.3 kJ/mol for S1, S2, S3 and S4, respectively.