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Two probiotic strains were co-encapsulated in water in oil emulsion by two methods: (1) coaxial wet electrospraying and (2) freeze-drying methods. Optimization of the wet electrospray technique for maximum yield, minimum sphericity factor, and size resulted in an alginate concentration of 2.99% w/v, flow rates ratio of alginate to the emulsion of 4.81, and applied voltage of 10 kV. The cell viability of Lactobacillus plantarum PTCC 1896 was the same after both encapsulation techniques, while the freeze-drying method was more impressive (97.25%) than the coaxial electrospraying (86.46%) in maintaining the viability of Bifidobacterium animalis subsp. Lactis. Exposing electrospray-encapsulated probiotics to simulated gastrointestinal conditions for 4 h resulted in only a one logarithmic cycle decrease in the viability of both bacteria. The number of live cells remained at more than 108 CFU g−1. In contrast, the viability of freeze-dried probiotics was reduced to about 107 CFU g−1. The freeze-dried B. lactis was the most sensitive probiotic to simulated gastric conditions. Monitoring the viability of bacteria during storage at −18 °C for both wet electrospraying and freeze-drying methods showed that the number of living microorganisms was more than 6 Log CFU g−1 after 5 and 4 months, respectively. • Bifidobacterium lactis and Lactobacillus plantarum were double protected. • Wet electrospraying and freeze-drying assisted the w/o emulsion for encapsulation. • Wet coaxial-electrospraying was fully optimized for encapsulation of probiotics. • The viability at −18 °C for both methods was acceptable after 4 months. • Electrospray was more effective at protecting probiotics in the simulated GI tract. [ABSTRACT FROM AUTHOR]

Lactobacillus plantarum and Bifidobacterium lactis were co-encapsulated separately with either inulin or resistant starch in Ca-alginate/chitosan microcapsules by electro-hydrodynamic atomization (EHDA). Encapsulation yield of core materials and their release profile were studied. Protective role of polysaccharide matrix on bacteria under gastrointestinal (GI) conditions and storage at 25, 4 or −18 °C were investigated. Encapsulation yield was calculated to be 98, 79 and 99 percent for bacteria, inulin and resistant starch, respectively. Ten percent of inulin was expelled from the Ca-alginate network into water after 24 h; however, no resistant starch was released. Chitosan coating reduced the release of inulin by up to 5 percent. Survival studies showed 5.90 ± 0.3 log CFU/g of Lb. plantarum and 7.19 ± 0.15 log CFU/g of B. lactis survived GI conditions in starch-containing microcapsules. Viability loss of Lb. plantarum was successfully restricted during storage at room temperature by encapsulation in Inulin-containing microcapsules as 6.33 ± 0.21 log CFU/g survived after 90 days storage. The findings revealed EHDA can be employed for co-encapsulation of probiotics and high molecular weight prebiotics in micron-sized capsules which could open up a new perspective for targeted delivery of live cells to the colon through foods. • Probiotic survival under acidic condition was enhanced by encapsulation in a polysaccharide matrix. • Co-encapsulation of B. lactis and starch granules improved bacterial survival during storage. • High encapsulation efficiency of probiotics-prebiotics was achieved by electro-hydrodynamic atomization. • Release of inulin from Ca-alginate network was retarded by chitosan coating. [ABSTRACT FROM AUTHOR]

Abstract In this study, we aimed to evaluate the possibility of obtaining natural high-resistant protein capsules from aqueous solution of whey protein containing transglutaminase (TG) enzyme through electrohydrodynamic atomization (EHDA) as an appropriate system, and freeze-drying (FD) technique as the control method for encapsulation of Lactobacillus casei. A stable cone jet was achieved in a certain electrical conductivity, surface tension, and viscosity values equal to 1681 ± 8.49 μS, 48.97 ± 0.02 mN/m, and 51.96 ± 0.78 cP, respectively. Spherical water-resistant capsules with an average diameter of 3.09 ± 1.04 μm were obtained through the EHDA process. A comparison between the EHDA and FD revealed higher encapsulation efficiency of the electrospraying technique as well as greater viability of L. casei under the simulated gastrointestinal (GI) tract. DSC results showed that the enthalpy of cross-linked samples was decreased by incorporating TG enzyme. In contrast to freeze-dried structures, electrosprayed capsules revealed better protection during the storage, especially in the second and third months. Highlights • Encapsulation of L. casei in high-resistant capsules by electrospraying process. • Characterization of whey protein solutions with/without transglutaminase enzyme. • Characterization of the electrosprayed and freeze dried structures. • The survival rate of L. casei was reached up to 99.4% in high-resistant capsules. • Effect of gastrointestinal tract and storage time on the viability of L. casei. [ABSTRACT FROM AUTHOR]

In this work, tri-layered nanofibers including zein (30% w/v) in top/bottom layers and the optimal volume ratio of polyvinyl alcohol (PVA, 10% w/v)/basil seed gum (BSG, 1% w/v) with lycopene in the middle layer was used to enhance the bioaccessibility of lycopene. Viscosity, electrical conductivity, and surface tension of BSG/PVA solutions in different volume ratios were measured. According to SEM images, it was found that the solution with BSG to PVA ratio of 70:30 ratio was the best nanofiber for trapping lycopene. The encapsulation efficiency of lycopene in tri-layered nanofibers was in the range of 81.7–92.26%. According to the DSC diagram, lycopene was successfully encapsulated in tri-layered nanofibers. DSC diagrams confirmed the improvement of lycopene thermal resistance in tri-layered nanofibers. The FTIR analysis showed no chemical interaction between the tri-layered nanofiber components. The bioaccessibility of lycopene in the small intestine using tri-layered nanofiber was 16.18%. The release behavior of lycopene was studied by Kopcha, Higuchi, Korsmeyer-Peppas, and Peppas-Sahlin models, which showed that the diffusion and erosion mechanisms were involved in the release of lycopene from tri-layered nanofibers in simulated gastrointestinal media. [Display omitted] • Lycopene bioaccessibility was increased by using tri-layered nanofibers. • The bioaccessibility of lycopene using tri-layered nanofiber was 16.18%. • Diffusion and erosion mechanisms were involved in the release of lycopene. • The Korsmeyer-Peppas model had the best description for lycopene release. [ABSTRACT FROM AUTHOR]

In this work, electrospinning and electrospraying techniques were used to encapsulate the sensitive bioactive compounds of a saffron extract (i.e. picrocrocin, safranal, and crocin) using zein as protective matrix. Initially, a dried saffron extract (DSE) was obtained and characterized and was subsequently incorporated within zein solutions prepared at two concentrations (10% w/v for capsules and 20% for fiber development). The greatest encapsulation efficiency was observed for the fiber samples, with retention values for picrocrocin, safranal, and crocin of up to 97, 88, and 97%, respectively. The stability of the free and encapsulated extract when exposed to UV light, different pH (2, 7.4) and temperatures (25, 75 °C) was also studied. The photostability of crocin and safranal was significantly (p < 0.05) increased upon encapsulation. Similarly, while about 98% of the non-encapsulated crocin degraded after 15 h of exposure to acetic acid at 75 °C, only 67.23% of the encapsulated compound was lost under the same conditions. The release profiles of crocin, safranal and picrocrocin from the encapsulation structures were fitted using the Peppas-Sahlin model (R 2 = 0.98), showing that the dominant release mechanism was diffusion. Finally, the encapsulation structures retained their integrity upon contact with water, highlighting their potential use as food packaging coatings. • A saffron extract was produced and encapsulated by electrohydrodynamic processing. • High encapsulation efficiencies (74–97%) were achieved. • Stability of crocin upon UV exposure was significantly increased (p < 0.05). • The release of bioactive components in a food simulant was modeled. • The encapsulation structures kept their integrity upon water contact. [ABSTRACT FROM AUTHOR]

The objective of this work was to investigate whether the use of unpurified agar-based fractions extracted from the seaweed Gelidium as microencapsulation matrices has an impact on probiotic protection during storage. Therefore, unpurified and pure agar and agarose-based microcapsules were produced through emulsification/internal gelation for the protection of Bifidobacterium pseudocatenulatum CECT 7765. Initially, agarose-based formulations with other biopolymers were evaluated, given the excellent oxygen barrier properties of this polysaccharide. The optimal combination in terms of probiotic protection was selected for further experiments and this agarose-based formulation was compared with microcapsules produced using both pure and unpurified agar-based fractions. The presence of other compounds (mainly proteins and polyphenols) in the unpurified agar fractions significantly improved the viability of these sensitive probiotic bacteria both at ambient and refrigerated storage conditions. Furthermore, the presence of impurities allowed the increase of solids content in the formulation giving raise to stronger gel particles, which could contribute to limited oxygen diffusion, thus, partly explaining the improved protection. Therefore, this work demonstrates the potential of more cost-effective less purified carbohydrate-based fractions for probiotic protection. [ABSTRACT FROM AUTHOR]