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Cellulase can increase the soluble dietary fiber (SDF) content in Rosa roxburghii Tratt (RRT), but the effects on polyphenol content, bioactivity, and flavor are unknown. This study analyzed the changes in SDF content, total phenolic content, antioxidant activity and flavor before and after cellulase treatment. Cellulase treatment increased the SDF and total phenolic content of RRT by 13 % (P < 0.05) and 25.68 % (P < 0.05), respectively, and increased the antioxidant activity. HS-GC-IMS identified a total of 42 volatile compounds present, and ROAV analysis revealed that the characteristic aroma compounds of RRT were mainly aldehydes, alcohols, and ethers. The electronic nose and tongue results were consistent with the HS-GC-IMS analysis, indicating the positive effect of cellulase on the quality of RRT. Cellulase treatment significantly improved the oxidative activity and flavor performance of RRT. These results of RRT, providing practical guidance for improving the flavor and product quality.

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In this study, a synthesis process based on the microemulsion method (ME) was developed with the aim to produce controlled-size starch nanoparticles (SNPs). Several formulations were tested for the preparation of the W/O microemulsions varying the organic/aqueous phase ratios and co-stabilizers concentrations. SNPs were characterized in terms of size, morphology, monodispersity and crystallinity. Spherical shape particles with mean sizes 30-40 nm were prepared. The method was then used to simultaneously synthesize SNPs and iron oxide nanoparticles with superparamagnetic properties. Starch-based nanocomposites with superparamagnetic properties and controlled size were obtained. Therefore, the microemulsion method developed could be considered an innovative technology for the design and development of novel functional nanomaterials. The starch-based nanocomposites were evaluated in terms of morphology and magnetic properties, and they are being considered as promising sustainable nanomaterials for different biomedical applications.

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Crustacean byproducts are valuable sources of astaxanthin. In this study, an astaxanthin-rich lipid phase was extracted from shrimp waste and encapsulated in multilayer emulsions. Stabilized by electrostatic complexes of whey protein isolate (WPI) and Persian gum (PG), the multilayer emulsions were created by different WPI:PG mixing ratios (1:2-1:4). The resultant emulsions were then exposed to lyophilization. The encapsulation efficiency of astaxanthin in lyophilized powders was 42.9-49.8 (g astaxanthin/100 g astaxanthin). The moisture content and water activity of the powders decreased significantly (p < 0.05), but their solubility and hygroscopicity increased significantly (p < 0.05) in response to an increase in the PG content of the mixture (or by reducing the WPI:PG ratio). Morphological characterizations revealed the formation of smaller and more uniform microcapsules when higher amounts of PG were used. Water dispersibility was higher than 94 (g powder/100 g powder). The results of an accelerated stability test showed an improvement in astaxanthin chemical stability in the multilayer emulsions, particularly when the WPI:PG ratio was 1:4. A model beverage consisting of water (89 g/100 g), sugar (10 g/100 g) and citric acid (1 g/100 g) was prepared and the potential application of astaxanthin microcapsules as a natural colorant was studied and compared with a synthetic colorant (E110) under the effect of light/darkness, temperature (4 and 25 °C) and time (0-60 d). The encapsulated lipid extract imparted a highly stable color to the product which was comparable to the effect of the synthetic colorant. However, the astaxanthin concentration was highly affected by time and partially affected by light and temperature.

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Comprehensive 2D gas chromatography-time-of-flight mass spectrometry was combined with descriptive sensory analysis to elucidate the specificity of strong-aroma type Baijiu (Chinese liquor) from different regions, based on regionally distinct flavor characterized by chemical and sensory profiles. Numerous potential aroma compounds (262) were identified, among which 58 aroma compounds were significantly different between the samples from Sichuan and Jianghuai regions. Relationships between these potential aroma compounds and sensory attributes were investigated by partial least squares regression and network analysis. The compounds that dominantly contributed to the important sensory attributes were identified. The high pyrazines, furanoids, and carbonyls amounts contributed to the high intensities of the cellar, toasted, and grain aroma profiles of the Sichuan region samples, while the high ester and alcohol levels contributed to the fruity and floral aroma profiles of the Jianghuai region samples. This approach may have practical application in flavor characterization of other alcoholic beverages.

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A metabolomics strategy was developed to differentiate strong aroma-type baijiu (SAB) (distilled liquor) from the Sichuan basin (SCB) and Yangtze-Huaihe River Basin (YHRB) through liquid-liquid extraction coupled with GC×GC-TOFMS. PCA effectively separated the samples from these two regions. The PLS-DA training model was excellent, with explained variation and predictive capability values of 0.988 and 0.982, respectively. As a result, the model demonstrated its ability to perfectly differentiate all the unknown SAB samples. Twenty-nine potential markers were located by variable importance in projection values, and twenty-four of them were identified and quantitated. Discrimination ability is closely correlated to the characteristic flavor compounds, such as acid, esters, furans, alcohols, sulfides and pyrazine. Most of the marker compounds were less abundant in the SCB samples than in the YHRB samples. The quantitated markers were further processed using hierarchical cluster analysis for targeted analysis, indicating that the markers had great discrimination power to differentiate the SAB samples.

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Lipid sources as alternatives to fish oil could alter the nutritional value and flavor quality of crab meat affecting consumer preferences. Herein, an 8-week nutritional trial was designed to investigate the effects of dietary lipid sources including fish oil (FO), krill oil (KO), palm oil, rapeseed oil, soybean oil and linseed oil on profiles of amino acids, fatty acids and volatiles in muscle of swimming crab (Portunus trituberculatus). Volatiles of crab muscle were characterized by headspace solid-phase microextraction and gas chromatography-tandem mass spectrometry. Results revealed that crabs fed FO and KO had significantly higher levels of protein, indispensable amino acids, eicosapentaenoic acid and docosahexaenoic acid in muscle. Principal component analysis and hierarchical cluster analysis demonstrated that muscle volatiles of crabs fed different dietary oils exhibited significant variations. Dietary FO and KO significantly increased the relative levels of 3-methylbutanal, heptanal, benzaldehyde and nonanal in muscle, which may produce more pleasant flavors.

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The purpose of the present study was to determine the solubility of raloxifene hydrochloride (RHCl) in ten solvents: water, ethanol, isopropyl alcohol (IPA), ethylene glycol (EG), propylene glycol (PG), polyethylene glycol-400 (PEG-400), Transcutol, 1-butanol, dimethyl sulfoxide (DMSO), and ethyl acetate (EA) at temperatures of 298.2-323.2 K and a pressure of 0.1 MPa. The solubility data obtained was fitted upon "Apelblat and Van't Hoff" equations. The maximum mole fraction solubility of RHCl was obtained in DMSO (5.02 × 10-2 at 323.2 K), followed by PEG-400 (5.92 × 10-3 at 323.2 K), EA (3.11 × 10-3 at 323.2 K), Transcutol (1.22 × 10-3 at 323.2 K), PG (2.19 × 10-4 at 323.2 K), 1-butanol (1.96 × 10-4 at 323.2 K), IPA (1.47 × 10-4 at 323.2 K), ethanol (7.90 × 10-5 at 323.2 K), EG (6.65 × 10-5 at 323.2 K), and water (3.60 × 10-5 at 323.2 K). Similar fashions were noticed at each studied temperature. The higher solubility of RHCl in DMSO, PEG-400, EA, and Transcutol was possibly referable to their lower polarity in comparison with water. The molecular interactions between the solute and solvent molecules were estimated by calculating parameters like activity coefficients, and more prominent solute-solvent molecular interactions were noted for RHCl-DMSO, RHCl-EA, and RHCl-PEG-400 in comparison with the other solute-solvent combinations. The outcomes of the "apparent thermodynamic analysis" showed that the dissolution of RHCl was "endothermic, spontaneous and entropy-driven" in all investigated solvents. The obtained solubility data of RHCl in commonly used solvents could be useful in the purification, recrystallization, and dosage form design of the drug.

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The relative contributions of cotyledons and seed coats towards hardening of common beans (Phaseolus vulgaris) were investigated and the rate-limiting process which controls bean softening during cooking was determined. Fresh or aged whole beans and cotyledons were soaked and cooked in demineralised water or 0.1 M NaHCO3 solution, and texture evolution, microstructure changes and thermal properties were studied. Fresh and aged whole beans cooked in demineralised water had significantly different softening rate constants and so did fresh and aged cotyledons. The comparable softening rate constants of aged whole beans and cotyledons indicated an insignificant role of the seed coat in hardening during storage. All samples cooked faster in 0.1 M NaHCO3 solution. Disintegration of cooked tissues followed by microscopic examination revealed a transition from cell breakage through a phase of cell breakage and separation to complete cell separation with increased cooking time wherefore texture decayed. Therefore, progressive solubilization of pectin in the middle lamella greatly promoted texture decay. While residual birefringence even after substantial cooking time suggested some molecular order of the starch, calorimetric analyses revealed complete starch gelatinisation before complete cell separation occurred. This implies an insignificant role of starch in texture decay during cooking but its hindered uncoiling into a viscous gel after gelatinisation due to the restricting cell wall could promote its retrogradation. Therefore, we suggest that the rate-determining process in bean softening relates to cell wall/middle lamella changes influencing pectin solubilization.

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The aim of this study was to evaluate the effects of alcohol-acid degradation on the structural and physicochemical characteristics of guar gum. Guar gum (50wt.%) was treated with methanol, ethanol, 2-propanol, or 1-butanol containing 1 or 2mL 36% hydrochloric acid at 75°C for 30-240min. The linear relationship between 1/Mw and time suggested that alcohol-acid degradation followed first-order kinetics with rate constants varying directly with the number of alcohol carbon atoms and acid concentration. Alcohol-acid treatment exerted no effect on the chemical and crystal structure of guar but significantly decreased shear viscosity, slightly increased solubility, mildly reduced thermostability, and dramatically darkened colour. This study extended the knowledge of the effect of alcohol on the acid hydrolysis of guar and will contribute to the development of a large-scale procedure for guar gum degradation.

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Two field experiments were conducted over three growing seasons (2006-07, 2008-09 and 2009-10) to evaluate Se-enriched pasta through foliar fertilization at various rates and timing of application on 4 durum wheat varieties. Our findings confirm the effectiveness of foliar Se fertilization to increase Se concentrations in durum wheat grain, even at high Se rates (120gSeha(-1)). Se fortification was significant across different genotypes, with greater Se accumulation in landraces ('Timilia') and obsolete varieties ('Cappelli'), with respect to modern varieties. The Se content in the grain was increased by up to 35-fold that of the untreated control. The Se concentration decreased during milling (11%), while processing and cooking of pasta did not show significant decreases. This biofortification stategy had no effects on grain quality parameters, except for reduced gluten index in the high-gluten variety PR22D89, as well as for the sensorial properties of the spaghetti.

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In this study, the effects of different milling procedures (roller-milling vs. stone-milling) and pasta processing (fresh vs. dried spaghetti), and cooking on the antioxidant components and sensory properties of purple durum wheat were investigated. Milling and pasta processing were performed using one purple and one conventional non-pigmented durum wheat genotypes, and the end-products were compared with commercial pasta. The results show that the stone milling process preserved more compounds with high health value (total fibre and carotenoids, and in the purple genotype, also anthocyanins) compared to roller-milling. The drying process significantly (p<0.05) reduced the content of anthocyanins (21.42 µg/g vs. 46.32 µg/g) and carotenoids (3.77 µg/g vs. 4.04 µg/g) with respect to the pasteurisation process involved in fresh pasta production. The sensory properties of pasta from the purple genotype did not significantly differ from commercial wholemeal pasta, and its in vitro glycemic index was even lower. Thus, it is possible to consider this genetic material as a good ingredient for the production of functional foods from cereals naturally rich in bioactive compounds.

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The provitamin A potential of landrace orange maize from different locations (A, B, C and D) of central Malawi has been evaluated. Physicochemical compositions, color, total carotenoid content (TCC), carotenoid profiles, and oxygen radical absorbance capacity (ORAC) and 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity as antioxidant capacities of maize were determined. Color values of orange maize had correlations with ß-cryptoxanthin (r>0.36). TCC of white and orange maize averaged 2.12 and 59.5 mg/kg, respectively. Lutein was the most abundant carotenoid (47.8%) in orange maize, followed by zeaxanthin (24.2%), ß-carotene (16.4%) and ß-cryptoxanthin (11.6%). Location D showed the highest levels of lutein, zeaxanthin and antioxidant capacity. Provitamin A content of orange maize met the target level (15 µg/g) of biofortification. Retinol activity equivalent (RAE) from ß-cryptoxanthin and ß-carotene in orange maize averaged 81.73 µg/100g. In conclusion, orange maize has the potential to be a natural source of provitamin A.

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A new biomembrane-mimetic liquid chromatographic method using a C8 stationary phase and phosphatidylcholine-modified (PC-modified) microemulsion mobile phase was used to estimate unionized and ionized drugs lipophilicity expressed as an n-octanol/water partition coefficient (logP and logD). The introduction of PC into sodium dodecyl sulfate (SDS) microemulsion yielded a good correlation between logk and logD (R(2)=0.8). The optimal composition of the PC-modified microemulsion liquid chromatography (PC-modified MELC) mobile phase was 0.2% PC-3.0% SDS-6.0% n-butanol-0.8% ethyl acetate-90.0% water (pH 7.0) for neutral and ionized molecules. The interactions between the analytes and system described by this chromatographic method is more similar to biological membrane than the n-octanol/water partition system. The result in this paper suggests that PC-modified MELC can serve as a possible alternative to the shake-flask method for high-throughput unionized and ionized drugs lipophilicity determination and simulation of biological processes.

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