Properties and kinetics of the in vitro release of anthocyanin-rich microcapsules produced through spray and freeze-drying complex coacervated double emulsions.

This study aimed to prepare anthocyanin-rich microcapsules by spray and freeze-drying complex coacervated double emulsion using gelatin-acacia gum (GE-AG) and chitosan-carboxymethylcellulose (CS-CMC) and to investigate their properties and in vitro release kinetics. Microencapsulation efficiency (MEE) of the microcapsules varied from 84.9% to 94.7%. CS-CMS microcapsules showed significantly higher MEEs than those of GE-AG microcapsules. A significant higher MEE and lower moisture content and hygroscopicity was observed in spray-dried double emulsion (SDE) microcapsules. Freeze-dried double emulsion (FDE) microcapsules possessed higher total anthocyanin and total phenolic contents. The best fit for release kinetics was achieved using first-order and Higuchi models for SDE and FDE microcapsules, respectively. Diffusion-controlled release in the simulated gastric fluid was found for SDE microcapsules, while erosion-controlled release in simulated gastric and intestinal fluids predominated for FDE microcapsules. These findings suggest that the microcapsules can be applied for loading anthocyanins as a nutraceutical with controllable release requirement.

Influence of heat and moisture treatment on carotenoids, phenolic content, and antioxidant capacity of orange maize flour.

The aim of this work was to study the effect of heat and moisture treatment (HMT) on carotenoids, phenolic content and antioxidant capacity of ground, orange maize. Total carotenoid content (TCC) of untreated sample (53.39 mg/kg) was 2.2 times higher than measured in treated orange maize f (24.61 mg/kg). The rates of degradation with HMT were in the following order: ß-carotene > ß-cryptoxanthin > zeaxanthin > lutein. There was a significant interaction between longer heating time and higher moisture content on carotenoid degradation (p < .05). Total phenolic content (TPC) in raw sample (1664.74 mg/kg) was two-fold higher than in treated orange maize (827.89 mg/kg). Ferulic acid was the most abundant and stable phenolic acid in raw and treated orange maize. The antioxidant capacity of orange maize was higher in methanol than in butanol extracts. The highest correlation (0.924) was observed between TPC and ABTS+ scavenging capacity of methanol extracts.

A comparative study on chitosan/gelatin composite films with conjugated or incorporated gallic acid.

Gallic acid-grafted-chitosan (GA-g-CS) was synthesized in the presence of 1-ethyl-3-(3'-dimethylaminopropyl) carbodiimide and hydroxybenzotriazole under room temperature. To develop a kind of newly functional film, CS, gelatin, glycerol and Tween 20 were utilized to prepare CS-based composite films with incorporated GA (GA-CS) or conjugated GA (GA-g-CS), and the films were characterized in aspects of physical and functional properties, as well as microstructures. With the increasing of GA concentration, there was a reduction in transmittance, elongation at break and water vapor permeability (WVP) for GA-CS film. For GA-CS films, the higher tensile strength and lower WVP could be obtained when GA was evenly distributed across the films. Different from the GA-CS films, water solubility, swelling ratio, water vapor permeability and scavenging activities on 2,2-Diphenyl-1-picrylhydrazyl/2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) radicals were enhanced for GA-g-CS films, which could be ascribed to the rough surface morphology. The GA-g-CS films exhibited enhanced water vapor permeability when the substitution degree of GA increased. Also, the antimicrobial activities of GA-g-CS films were superior to those of GA-CS films. Our present work developed a way to prepare GA-g-CS films that owned many desirable properties and could be explored as promising biomaterials in food packaging.

LC-MS phenolic profiling combined with multivariate analysis as an approach for the characterization of extra virgin olive oils of four rare Tunisian cultivars during ripening.

In this work, the phenolic composition of four rare cultivars grown under the same agronomical and environmental conditions was studied. This is to test the effects of cultivars and ripening index essentially on phenolic composition in olive oils as well as tocopherols composition, organoleptic profiling and oxidative properties. Furthermore, some agronomical traits were determined in which a general increase in the size of the fruit and oil contents were recorded for all cultivars. The phenolic fractions were identified and quantified using liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MS/MS) in multiple reaction monitoring mode (MRM). A total of 13 phenolic compounds belonging to different chemical families were determined. Qualitative and quantitative differences in phenolic composition were observed among cultivars and also among sampling times. On the contrary to the agronomical traits, a general decrease (p<0.05) of total phenolic compounds was observed during maturation. Likewise, a decrease in tocopherols concentrations and oxidative properties was observed.

Development of bacterial cellulose based slow-release active films by incorporation of Scrophularia striata Boiss. extract.

Novel bacterial cellulose (BC) based monolayer and multilayer films, incorporating 5wt.% Scrophularia striata Boiss. extract (SE) were obtained. The effect of lamination and ß-cyclodextrin (ß-CD) inclusion complexation of SE on morphological, physical, antioxidant and release properties of films were investigated. FT-IR results reflected that some new interactions have occurred between BC and ß-CD. The XRD analyses showed a decrease in diffraction intensities of BC by addition of free SE. SEM results indicated that the intrinsic compactness of the BC film was preserved by addition of SE/ß-CD complex. Lamination and SE/ß-CD addition enhanced the mechanical properties. SE loaded films exhibited a good antioxidant activity. Release studies indicated that the release rate and diffusion coefficient (D) of SE in 95% ethanol simulant were significantly decreased by lamination and complexation of SE with ß-CD. Results suggest that SE loaded BC films may be used as controlled release antioxidant food active packaging.

Provitamin A potential of landrace orange maize variety (Zea mays L.) grown in different geographical locations of central Malawi.

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.

Effect of sugarcane molasses extract on the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in a model system.

Molasses, the main by-product of sugar production, is a well-known source of antioxidants. In this study, sugarcane molasses extract was investigated for its total phenolic content and in vitro antioxidant capacity. The experimental total phenolic content was 101.3 mg of gallic acid equivalent (GAE) in 1 g of extract, IC50 of Trolox and sugarcane molasses extract were 125.33 µg/ml and 126.0 µg/ml, respectively. A chemical model system showed that the sugarcane molasses extract effectively reduced the formation of phenylacetaldehyde and the aldol condensation product, meanwhile, the amount of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) also decreased. This could be due to the reaction between the phenolic compounds of sugarcane molasses extract and the carbonyl group of phenylacetaldehyde inhibiting the aldol condensation product formation, and this would suppress the formation of PhIP. A pathway that phenolic compounds inhibited the formation of PhIP is proposed. This pathway also suggested a mechanism for how the sugarcane affects the formation of PHIP.