Some physical properties and adsorption isotherms of vacuum-dried honey powder with different carrier materials

Structural and Release Properties of Combined Curcumin Controlled-Release Tablets Formulated with Chitosan/Sodium Alginate/HPMC

Controlled-release tablets offer several benefits, such as controlled release, odor masking, ease of use, stability, extended shelf life, and reduced production costs. This study developed combined curcumin controlled-release tablets (CCCTs) to increase the bioavailability of curcumin with hydroxypropyl methylcellulose (HPMC), chitosan, and sodium alginate. The hardness of the CCCTs was 5.63-1.98 kgf, friability was 0.00-1.22%, and disintegration time was 0.00-401.25 min. Differential scanning calorimetry and Fourier-transform infrared spectroscopy indicated a high compatibility between the excipients and curcumin. CCCTs with chitosan formed a gel structure, impeded disintegration, and reduced the release rate to 72.5% in simulated gastric fluid. In simulated intestinal fluid, CCCT with the HPMC-sodium alginate group formed a polyelectrolyte membrane hydrogel to prolong release from 6 to 12 h. This study developed various CCCT formulations that can be delivered through the gastric or intestinal tracts, using chitosan and HPMC-sodium alginate as excipients, respectively. CCCT can be used as a reference strategy for controlled-release curcumin delivery in the functional and healthcare supplement development.

Ultrasound assisted extraction of red cabbage and encapsulation by freeze-drying: moisture sorption isotherms and thermodynamic characteristics of encapsulate

In the present study encapsulation of ultrasound assisted red cabbage extract was carried out using four different carrier agents such as maltodextrin, gum arbic, xanthan gum, and gellan gum. Among the four hydrocolloids investigated, maltodextrin was found to have the least destructive effect on anthocyanin content (14.87 mg C3G/g dw), TPC (54.51 ± 0.09 mg GAE/g dw), TFC (19.82 Mg RE/g dw) and antioxidant activity (74.15%) upon freeze-drying. Subsequently a storage study was conducted using maltodextrin as carrier agent at 25-50 °C. The Clausius-Clapeyron equation was used to evaluate the net isosteric heat (qst) of water adsorption. The differential entropy (ΔS) and qst decreased from 82.298 to 38.628 J/mol, and 27.518 kJ/mol to 12.505 kJ/mol, respectively as the moisture content increased from 2 to 14%. The value of isokinetic energy and Gibb's free energy were found to be 364.88 and - 1.596 kJ/mol for freeze dried red cabbage.

Graphical abstract

Impact of the Drying Procedure and Botanical Origin on the Physico-Chemical and Potentially Bioactive Properties of Honey Powders

This study was aimed at researching the impact of the drying procedure (using the most appropriate honey-maltodextrin concentration for each drying technique) and botanical origin of honey on the physicochemical and potentially bioactive properties of honey powders that were made using maltodextrin as a carrier. The research was carried out with thyme, lavender, vetch and multifloral honey dehydrated using vacuum drying and freeze drying. The analysed parameters were moisture, water activity, colour, glass transition temperature, powder recovery, hygroscopic index and rate, tapped density, solubility, and phenolics as well as antiradical (ABTS•+, ROO•, •OH and O2•-), anti-inflammatory and antimicrobial (against Staphylococcus aureus, Escherichia coli and Listeria monocytogenes) activities. Freeze drying provided the highest recoveries. Powders obtained using freeze drying showed higher moisture and solubility as well as lower glass transition temperature, density and hygroscopicity than those obtained using vacuum drying. Hygroscopicity, glass transition temperature and antimicrobial activity against St. aureus depended on the drying procedure-honey concentration. Colour, anti-O2•- activity and antimicrobial activity against L. monocytogenes depended on the botanical origin of the raw honey. Moisture, solubility, density, total phenolic content, anti-ABTS•+ and anti-ROO• activities as well as anti-inflammatory activity and antimicrobial activity against E. coli depended on the drying procedure-honey concentration and botanical origin.

Microstructured lipid microparticles containing anthocyanins: Production, characterization, storage, and resistance to the gastrointestinal tract

Anthocyanins from grape peel extract have several biological properties and can act as a natural colorant and antioxidant agent. However, these compounds are susceptible to degradation by light, oxygen, temperature, and the gastrointestinal tract. Thus, this study produced microstructured lipid microparticles (MLMs) containing anthocyanins by the spray chilling technique and evaluated the particle stability. trans-free fully hydrogenated palm oil (FHPO) and palm oil (PO) were used as encapsulating materials in the ratios 90:10, 80:20, 70:30, 60:40, and 50:50, respectively. The concentration of grape peel extract was 40 % (w/w) in relation to the encapsulating materials. The microparticles were evaluated for thermal behavior by DSC, polymorphism, FTIR, size distribution and particle diameter, bulk density, tapped density, flow properties, morphology, phenolic compounds content, antioxidant capacity, and retention of anthocyanins. Furthermore, the storage stability of the microparticles was investigated at different temperatures (-18, 4, and 25 °C), and the anthocyanins retention capacity, kinetic parameters (half-life time and degradation constant rate), total color difference, and visual aspects were evaluated during 90 days of storage. The resistance of MLMs to the gastrointestinal tract was also evaluated. In general, higher FHPO concentrations increased the thermal resistance of the MLMs and both showed defined peaks of β' and β forms. The FTIR analysis showed that the MLMs preserved the original forms of their constituent materials even after atomization, with interactions between them. The increase in the PO concentration directly affected the increased mean particle diameter, agglomeration, and cohesiveness, as well as lower bulk density, tapped density, and flowability. The retention of anthocyanins in MLMs ranged from 81.5 to 61.3 % and was influenced by the particle size, with a better result observed for the treatment MLM_90:10. The same behavior was observed for the phenolic compounds content (1443.1-1247.2 mg GAE/100 g) and antioxidant capacity (1739.8-1660.6 mg TEAC/100 g). During the storage, MLMs made with FHPO to PO ratios of 80:20, 70:30, and 60:40 showed the highest stability for anthocyanin retention and color changes at the three temperatures (- 18 °C, 4 °C, and 25 °C). The gastrointestinal simulation in vitro revealed that all treatments were resistant to gastric phase and maintained a maximum and controlled release in the intestinal phase, demonstrating that FHPO together with PO are effective to protect anthocyanins during gastric digestion, and can improve the bioavailability of this compound in the human organism. Thus, the spray chilling technique may be a promising alternative for the production of anthocyanins-loaded microstructured lipid microparticles with functional properties for various technological applications.

Sorption Isotherms, Glass Transition and Bioactive Compounds of Ingredients Enriched with Soluble Fibre from Orange Pomace

Citrus fruits are one of the main crops worldwide. Its industrialization, primarily juice production, produces large amounts of byproducts, composed of seeds and peels, that can be used to obtain new ingredients. In this study, sorption behaviour, glass transition, mechanical properties, colour and bioactives of four different soluble fibre-enriched powders obtained from orange pomace using green technologies were studied. Powders were equilibrated at water activities between 0.113 and 0.680 for fifteen weeks at 20 °C, and studies were performed to indicate the best storing conditions to ensure the glassy state of the amorphous matrix and higher bioactive stability. By combining the Gordon and Taylor model with the Henderson isotherm, the critical water activity and content for storage in a glassy state were determined. The ingredient obtained after extrusion + hot water is the most stable, which is also the one with the highest dietary fibre content. Powder obtained by jet cooking is the least stable, as it is not in a glassy state at any water activity at room temperature. To increase storage stability, these should be stored at refrigeration temperatures.

Investigation of sorption isotherms of wheat germ for its effect on lipid oxidation

This research aimed to investigate the oxidation and sorption isotherm properties of wheat germ and to determine monolayer moisture content (m₀ ) in particular, because it has a limiting effect on lipid oxidation. This research comprised two stages. The first stage was the determination of sorption properties and m₀ at three temperatures (15, 25, and 35°C). The second stage of the research was to investigate lipid oxidation properties of stored wheat germ at two different temperatures (4 and 25°C) and m₀ for 28 days. As a result, it was determined that wheat germ has a Type II sorption isotherm, Halsey is the best fitting sorption equation, and the average m₀ is 4.25 g moisture per 100 g dry matter. Furthermore, the free fatty acid and peroxide value of wheat germ oil increased with increasing storage moisture content and temperature, determined as 12.63% and 5.01 mEqO₂ /kg on average, respectively. In conclusion, storage of impermeably packaged wheat germ at low temperature and m₀ content is an applicable method for decreasing rancidity and prolonging shelf-life.

Experimental and Modeling Investigations on the Water Sorption Behaviors of Autoclaved Aerated Concrete

The thermal and moisture properties of building envelope materials determine their performance over many years of use. Moisture has a particularly negative impact, impairing all the technical parameters and adversely affecting the microclimatic conditions inside the building. This article presents research and analysis on the moisture behavior of partitions made of autoclaved aerated concrete. Autoclaved aerated concrete is a very popular material for building external walls because of its relatively good thermal insulation and sufficient strength, if it is not subjected to increased moisture. This study investigated how the moisture content of this material changes with the change in relative air humidity. The four most popular density classes were studied. The sorption isotherms were determined by the static gravimetric method throughout the whole hygroscopic range. Moreover, the applicability of various models to describe sorption isotherms of this material group has been extensively evaluated. The tested models (Peleg, Redlich, Chen, Oswin, Henderson, Lewicki, Caurie, and GAB) all provided a very good fit with the experimental results for the tested material group (R² ranged from 0.9599 to 0.9978). This paper indicates that the use of two additional approximation parameters (SSE and RMSE) allows a more precise assessment of the quality of individual models.