Whey Drying on Porous Carriers

ABSTRACT

Whey is an undurable product. treated very often as a waste which pollutes the natural environment. Whey which is a valuable source of protein, lactose, vitamins and mineral salts should be utilized completely. The present paper is a proposal of whey drying on porous carriers. It is proved experimentally that the proposed drying method guarantees good product quality.     

Simulation and Experimental Validation of the Denaturation of a Whey Protein-Based Coating During Convection and/or Infrared Drying on a Plastic Film and Influence on its Oxygen Barrier Properties

The in-process denaturation of native whey protein-based coatings, film temperature, residual humidity, and protein degree of denaturation was simulated with combined existing models. The simulation was validated experimentally through determining the degree of denaturation of the protein in the coating. Whey protein-based formulations were applied, and denaturation was induced via infrared heating during the drying process. The oxygen transmission rate was measured and correlated with the degree of denaturation. The observed influence of the denaturation degree allowed the identification of a critical denaturation degree improving oxygen barrier. The developed simulation appears as an efficient tool for optimizing the processing and properties of protein-based materials.     

Highfrequency Drying of Porous Material

ABSTRACT

Highfrequency drying of a porous ceramic has been studied experimentally. The influence of electrode voltage, electrode distance, electric conductivity of the moisture and geometry of the product on the drying rate was investigated. There exists an optimal conductivity for maximum power dissipation and the geometry of the product has a focusing effect on the electric field. A theoretical discussion concludes, that the eddy current free quasi-stationary field is the type of field commonly present in highfrequency drying. With this type of field and the fact, that the complex permittivity of the product changes during drying, the experimental observations can be understood. From theory and experiment, conclusions are drawn in respect to a typical drying curve at highfrequency drying.     

Highfrequency Drying of Porous Material

Highfrequency drying of a porous ceramic has been studied experimentally. The influence of electrode voltage, electrode distance, electric conductivity of the moisture and geometry of the product on the drying rate was investigated. There exists an optimal conductivity for maximum power dissipation and the geometry of the product has a focusing effect on the electric field. A theoretical discussion concludes, that the eddy current free quasi-stationary field is the type of field commonly present in highfrequency drying. With this type of field and the fact, that the complex permittivity of the product changes during drying, the experimental observations can be understood. From theory and experiment, conclusions are drawn in respect to a typical drying curve at highfrequency drying.     

Microwave Drying of Porous Materials

Abstract

Experimental results on microwave drying of the porous particles exposed to air stream at 40°C are presented. The temperature and moisture distribution inside a particle were measured for gypsum spheres of 9, 18, 28, and 38 mm. The mass reduction was monitored during the drying process. The rate of drying and changes in temperature and moisture profiles for different drying conditions were analyzed and compared with the ones for convective drying.     

Microwave Drying of Porous Materials

Experimental results on microwave drying of the porous particles exposed to air stream at 40°C are presented. The temperature and moisture distribution inside a particle were measured for gypsum spheres of 9, 18, 28, and 38 mm. The mass reduction was monitored during the drying process. The rate of drying and changes in temperature and moisture profiles for different drying conditions were analyzed and compared with the ones for convective drying.     

Separation of Whey Proteins using Cascaded Ultrafiltration

Whey protein isolate, containing α-Lactalbumin and β-Lactoglobulin, was separated by using a continuous three-stage ultrafiltration cascade system. Single-stage experiments were optimized to enable good and stable cascade operation. Three different cascade configurations, a non-constrained ideal system (Configuration A), and adapted version (Configuration B), and a countercurrent cascade (Configuration C) were experimentally tested and compared. The countercurrent cascade system showed the traditional trade-off between yield and purity. Both the adapted cascade system and the non-constrained ideal cascade gave better performance in terms of recovery and purity and show potential for application, albeit for different purposes.     

Comparison of the Efficiency of Five Different Drying Carriers on the Spray Drying of Persimmon Pulp Powders

The aim of this work was to compare the efficiency of different carrier agents (maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin) on the powder recovery and physicochemical properties of persimmon powders produced by spray drying. Moisture content, water activity, hygroscopicity, solubility index, total phenol retention, color parameters, particle size, morphology, crystalline state, and sorption isotherms of persimmon powders were determined. No powder was recovered when the persimmon pulp was spray dried alone. The amount of maltodextrin, gum arabic, starch sodium octenyl succinate, whey protein concentrate, and egg albumin needed to obtain a powder recovery of 70% was 45, 30, 30, 25, and 10%, respectively. The use of maltodextrin, gum arabic, and starch sodium octenyl succinate resulted in higher total polyphenol retention and better reconstitution properties, but the powders were paler than those with whey protein concentrate and egg albumin. All carriers could aid the formation of persimmon irregular spherical microcapsules. However, powders produced with maltodextrin and gum arabic had a smoother surface and a more spherical shape than powders produced with other carriers. In addition, powders produced with starch sodium octenyl succinate, whey protein concentrate, and egg albumin were more agglomerated and shriveled compared to those produced with maltodextrin and gum arabic. All experimental data of water adsorption were well fitted to the Guggenheim-Anderson-de Boer (GAB) model.     

Physicochemical Properties of Phytopharmaceutical Preparations as Affected by Drying Methods and Carriers

This article reports a study of the effects of the drying methods and drying carriers on system performance and physicochemical properties of spray- and spouted bed–dried phytopharmaceutical preparations from Bidens pilosa L. Colloidal silicon dioxide, β-cyclodextrin, maltodextrin dextrose equivalent (DE) 10, and microcrystalline cellulose were used as drying carriers. The dried product was characterized by the particle size and morphology, total flavonoid content, solubility, flowability, and water activity. High-performance liquid chromatography (HPLC) was used to detect four marker compounds previously reported for this plant. Spray and spouted bed drying systems were compared through energetic efficiency, product recovery, elutriation, and product accumulation. The crystalline state of the powders was assessed by X-ray diffraction. Results showed high degradation rates for total flavonoid content and marker compounds during spouted bed drying. Depending on the drying carrier added to extractive solutions, different degrees of protection from degradation were conferred, and the physical characteristics of the product were changed accordingly. The lowest flavonoid degradation (8.6%) and the higher concentration of marker compounds were obtained using β-cyclodextrin as the drying carrier. Particle size was higher when a blend of Aerosil (Evonik Degussa, Hanau, Germany) and cellulose was employed as the drying carrier. A maximum product recovery of 86.9% was achieved by spray drying and 72.9% by spouted bed drying with the Aerosil : cellulose composition.     

Research on the Degradation Kinetics Model in the Drying Process of Chinese Herb

Curative compositions such as catolpol in Rehmannia Glutinosa, flavone in Ophiopogon Japonicus and ginsenoside Re in Panax Ginseng in Chinese herbs were measured as the experimental indices by the method of high performance liquid chromatography under different drying conditions. The reaction order and parameters of the degradation kinetics model were determined and the model was verified by experiments. It was indicated that by comparing with the thin drying method, the prospective model could predict the degradation of curative compositions with drying time, temperature and moisture content of herbal materials with enough precision and could be used to simulate the degradation in the drying process of Chinese herb.     

中草药干燥过程中质量退化动力学模型的研究

Curative compositions such as catolpol in Rehmannia Glutinosa, flavone in Ophiopogon Japonicus and ginsenoside Re in Panax Ginseng in Chinese herbs were measured as the experimental indices by the method of high performance liquid chromatography under different drying conditions. The reaction order and parameters of the degradation kinetics model were determined and the model was verified by experiments. It was indicated that by comparing with the thin drying method, the prospective model could predict the degradation of curative compositions with drying time, temperature and moisture content of herbal materials with enough precision and could be used to simulate the degradation in the drying process of Chinese herb.     

Drying of Porous Materials in the Presence of Solar Radiation

ABSTRACT

We present a combined heat and moisture transfer model for predicting the drying characteristics of porous building materials exposed to solar radiation. The model has been validated for convective drying using published data and for radiative drying using results of an experimental study carried out using a solar lamp to simulate solar radiation conditions. Actual and predicted moisture content profiles and the drying rates when compared give favourable results.     

Whey protein aggregates-alginate composite gel for astaxanthin-chia oil encapsulation

Chia oil (rich in omega-3 fatty acids) and astaxanthin are associated with various benefits for human health. However, their low solubility and poor stability reduce their direct use as bioactive compounds. Its encapsulation within the appropriate material can be a solution in this case. This work evaluated the effect of whey protein aggregates (WPA) on the storage stability of chia oil-astaxanthin blends encapsulated in alginate gel beads. Bead characteristics and the stability of encapsulated bioactive compounds stored at 25°C for 30 days were evaluated. High values of encapsulation efficiency (>85%) were observed in the cases studied. The addition of WPA affected some characteristics of the beads and improved the stability of the bioactive compounds compared to pure alginate beads. After 30 days of storage, higher preservation of astaxanthin and lower content of lipid oxidation products were observed in beads with WPA compared to alginate beads.     

Simulation of Convective Drying of Wet Porous Materials

Abstract

A simulation model for convective drying of wet porous materials was developed. For the simulation, we measured the moisture diffusivities within them and applied a modified Dubinin-Astakhov equation to the moisture sorption data for a membrane filter. The simulation results not accounting for internal mass transfer resistance were quite different from the experimental ones. The drying characteristics calculated by a shrinking core model with effective moisture diffusivity represented a much lower drying rate and much higher temperatures, respectively, than the experimental ones. This meant that we must consider the plural moisture transport mechanisms within the samples. Therefore, we calculated the drying rate and temperatures with an apparent overall mass transfer coefficient damping with a decrease in the moisture content. The results accounting for the hygroscopic effects broadly agreed with the experimental ones by the evaluation.     

Simulation of Convective Drying of Wet Porous Materials

A simulation model for convective drying of wet porous materials was developed. For the simulation, we measured the moisture diffusivities within them and applied a modified Dubinin-Astakhov equation to the moisture sorption data for a membrane filter. The simulation results not accounting for internal mass transfer resistance were quite different from the experimental ones. The drying characteristics calculated by a shrinking core model with effective moisture diffusivity represented a much lower drying rate and much higher temperatures, respectively, than the experimental ones. This meant that we must consider the plural moisture transport mechanisms within the samples. Therefore, we calculated the drying rate and temperatures with an apparent overall mass transfer coefficient damping with a decrease in the moisture content. The results accounting for the hygroscopic effects broadly agreed with the experimental ones by the evaluation.     

基于薄层干燥模型的褐煤干燥动力学研究

在不同颗粒直径和不同的干燥介质温度下,对褐煤进行干燥动力学实验研究。得到了褐煤的干燥曲线和干燥速率曲线,采用薄层干燥模型对实验数据进行模拟,得到了褐煤的干燥方程和干燥速率方程。提出了褐煤干燥速率常数的经验公式k=A exp[（-E_v（1+C_dlnd））/（RT）],其中指前因子A=5.819min^-1,界面蒸发活化能E_v=21347.5KJ/mol,经验常数C_d=0.0409m^-1,干燥时间指数n=1.516。     

冷冻干燥法制备层状多孔羟基磷灰石支架过程中的溶剂升华行为

采用水基羟基磷灰石(hydroxyapatite,HA)浆料,经冷冻干燥和烧结工艺(1 250℃烧结3 h)制备了层状多孔HA支架.研究了冷冻温度、干燥压力和干燥温度对水基HA浆料中溶剂升华行为的影响.结果表明:随着冷冻温度的降低,多孔HA支架的层间距逐渐减小,支架的升华时间增加;由于样品的干燥过程同时受到传热和传质的...     

Whey Protein Isolate Coated Liposomes as Novel Carrier Systems for Astaxanthin

In this work, whey protein isolate (WPI)‐coated astaxanthin‐loaded liposomes are prepared by combining the fabrication of liposomes with the layer self‐assembly deposition technique. The physical properties of such composite carriers are evaluated by zeta potential, particle size, distribution, encapsulation efficiency, and morphology. WPI‐ coated astaxanthin‐loaded liposomes display homodisperse distribution and high encapsulation efficiency with a WPI coating layer surrounding the surface of conventional liposomes by the electrostatic interaction. Fourier transform infrared spectroscopy and X‐ray diffraction analysis reveal that WPI interacts with the lipid bilayer via hydrophobic forces and hydrogen bonding, which result in the successful coating. Based on experimental results of differential scanning calorimetry and thermogravimetric analysis, it is demonstrated that thermal stability of astaxanthin‐loaded liposomes benefits from the formation of surface modification of the WPI‐layer. In addition, the physical stability of WPI‐coated astaxanthin‐loaded liposomes under heating and light is significantly improved as compared with uncoated liposomes. This research might provide scientific guidance for the development of WPI‐coated liposomes as efficient carrier systems for bioactive substances in food and pharmaceutical industry. Practical Applications: To improve lipid membrane stability and to prevent the leakage of encapsulated astaxanthin, a novel carrier system based on WPI coated on the surface of liposomes is prepared through the layer self‐assembly deposition technique. This research suggests that WPI‐coated liposomes represent an effective and stable delivery system for astaxanthin. WPI‐coated liposomes could be developed as efficient carrier systems for bioactive compounds in the food and pharmaceutical industries.     

Drying of Agricultural Grains in a Multiple Porous Draft Tube Spouted Bed

A multiple porous draft tube spouted bed (MPDTSB) was used to carry out drying of Ragi (Eleusine coracana), Barley, and Wheat grains. Batch experiments were conducted under varied conditions of initial moisture contents of grains, air inlet temperatures, and airflow rates. The draft tube parameters and fluid inlet sizes were also varied in the study. The results indicated that MPDTSB has the potential to be used for scale up to large-scale solids drying. In addition, two single porous draft tube spouted beds (SPDTSBs) were used for comparison with MPDTSB; the batch drying times in the MPDTSB were found to be lower when compared to those in SPDTSB under identical operating conditions.