Fabrication and characterization of an active biodegradable edible packaging film based on sesame seed gum (Sesamum indicum L.)

Effect of different modified potato starch on starch-based films containing ZIF-67@thymol

Zeolite imidazolate framework-67 (ZIF-67) was used to encapsulate thymol (THY) to improve the properties of potato starch films. The effect of different modified potato starches (acetate starch (AS), hydroxypropyl di-starch phosphate (HDSP), oxidized hydroxypropyl starch (OHS), and acetylated di-starch phosphate (ADSP)) on the film properties was investigated. The results showed that the modified potato starch film had better water resistance, mechanical property, and water vapor barrier than the natural potato starch film. Scanning electron microscopy observations showed that the smoothness of the modified film was advanced. Notably, the OHS film had the best oxidation resistance activity of 76.93 % compared to the other four films. Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were significantly inhibited in all potato starch films enhanced with ZIF-67@THY. Therefore, starch-based films incorporating ZIF-67@THY have a broad application prospect in food packaging.

Effects of Concentration and Heating/Cooling Rate on Rheological Behavior of Sesamum indicum Seed Hydrocolloid

Hydrocolloids are known as natural hydrophilic biopolymers that can contribute viscosity and gelation in solution, as well as nutritional benefits, thus, they are widely used in the food industry. In our work, hydrocolloid was isolated by aqueous extraction of Sesamum indicum seed at 80 °C and pH 8.0. The chemical composition and functional properties of Sesamum indicum seed hydrocolloid (SISH) were characterized, and the effects of concentration including 1%, 2%, and 3% as well as heating/cooling rate (1, 5, and 10 °C/min) on the rheological behavior of SISH dispersions in aqueous solution were investigated. The viscoelastic properties of SISH dispersions were characterized by small-amplitude oscillatory shear measurement. The resultant SISH consisted of 60.95% carbohydrate and 23.32% protein, and was thus endowed with a relatively high water-holding capacity, solubility, appropriate emulsifying and foaming properties. Rheological results revealed that the aqueous dispersion of SISH exhibited a non-Newtonian shear-thinning flow behavior. The viscoelastic moduli changes were found to be dependent on SISH concentration, temperature, and heating/cooling rate. Increasing SISH concentrations from 1% to 3% promoted the development of stronger cross-link network. The mechanical spectra derived from strain and frequency sweep measurements showed that the storage moduli were always higher than the loss moduli, and the loss tangent was calculated to be above 0.1 and below 1.0. Furthermore, both moduli had slight frequency dependency, and the complex viscosity exhibited an almost linear reduction with the increase of frequency. Therefore, SISH dispersion behaved as a weak gel-like system. The hysteresis of viscoelastic moduli during heating and cooling reduced with decreasing the heating-cooling rates from 10 to 1 °C/min, suggesting that SISH molecules had enough time to develop a stable and thermally irreversible network. Overall, SISH can be regarded as an acceptable hydrocolloid for generating natural food components with intriguing functional and rheological qualities in the formulation of microstructured goods.

Engineering properties of Cassia tora L. seeds and meal as a function of moisture content

Engineering properties are of great importance for Cassia tora L. seeds in aspects of harvesting, handling mechanical design and product processing. The effect of moisture content (7, 10, 13, 16 and 19%) (wet basis) on the properties: physical (length, width, bulk and true density, porosity, thousand seeds mass, coefficient of static friction and angle of repose), mechanical (hardness, fragmentation energy and failure deformations), and thermal (specific heat, thermal conductivity and thermal diffusivity), were systematically studied. As the moisture contents increase from 7 to 19%, the length (L) increased from 4.52 to 5.87 mm, the thickness (T) from 2.51 to 3.21 mm and the width (W) from 2.36 to 3.02 mm, respectively. The bulk and true density of Cassia tora L. seeds decreased from 775.83 to 654.17 kg/m³ and from 1295.21 to 1154.72 kg/m³, respectively, with the moisture content raised from 7 to 19%. The thermal conductivity of Cassia tora L. seeds meal was found to be 0.068–0.098 W m⁻¹ K⁻¹, 0.078–0.112 W m⁻¹ K⁻¹, 0.089–0.125 W m⁻¹ K⁻¹, 0.098–0.136 W m⁻¹ K⁻¹, 0.108–0.148 W m⁻¹ K⁻¹, 0.119–0.159 W m⁻¹ K⁻¹, respectively, at 25 °C, 45 °C, 65 °C, 85 °C, 105 °C and 125 °C in moisture ranges of 7–19%. The thermal diffusivity was found to decrease from 5.21 × 10^–8 to 4.53 × 10^–8 m²/s, from 5.75 × 10^–8 to 4.91 × 10^–8 m²/s, from 6.11 × 10^–8 to 5.17 × 10^–8 m²/s, from 6.52 × 10^–8 to 5.36 × 10^–8 m²/s, from 7.17 × 10^–8 to 5.77 × 10^–8 m²/s, from 7.36 × 10^–8 to 5.84 × 10^–8 m²/s, respectively, at 25 °C, 45 °C, 65 °C, 85 °C, 105 °C and 125 °C in moisture ranges of 7–19%. The results suggested that physical properties exhibited linear relationships with moisture content using the regression model, while mechanical properties showed a second-order polynomial relationship with moisture content. Furthermore, significant variation existed in thermal properties because of differentiate moisture content and temperature. These data and rules are also useful for high efficiency machines design and mechanisms development.

Characterization of functional sweetened condensed milk formulated with flavoring and sugar substitute

In the present study, the effect of sugar replacement and enrichment with cinnamon extract (CE) on the physicochemical, functional, and organoleptic properties of sweetened condensed milk (SCM) and the production of flavored functional dairy dessert was investigated. The results demonstrated that by adding CE (0.5 and 1%) and fructose sugar (50 and 100% replacement) in the formulation containing maltodextrin, the physicochemical, functional, and organoleptic properties of SCM samples were improved. However, adding fructose and CE at the maximum concentration increased the acidity, particle size, redness (a), yellowness (b) and decreased the lightness (L), viscosity, and sensory scores of the SCM samples (p < .05). Scanning electron microscopy images demonstrated that as the fructose level increased, the number of cavities increased, while the size of the cavities decreased (p < .05). Microstructure analysis also showed that the application of CE increased the density of the structure in the SCM samples. However, the SCM samples formulated with maltodextrin, 0.5% CE, and 50% fructose substitution were identified as optimal samples. Evaluation of the functional properties of SCM formulated with 0.5% CE revealed that the total phenolic content (TPC) and DPPH radical scavenging activity were in the range of 139.21-143.24 mg GAE / g and 50.12%-52.01%, respectively.