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T he physical protection by microencapsulation is a new method to increase the survival of probiotic bacteria. The size of beads containing probiotics has signif-icant effect on organoleptic properties of foods. Reduction of the sphere size to less than 100 μm would be advantageous for texture considerations and allow direct addition of encapsulated probiotics to a large number of foods. In microencapsulation process, Tween 80 can be replaced by lecithin in order to prevent its detrimental effect on the viability of probiotic bacteria. Calcium alginate as an edible polymer was used for the microencapsulation of probiotic bacteria by emulsion technique. A modified microencapsulation method based on emulsion technique was investigated in this study to produce microcapsules with diameters below 100 μm. A completely random-ized design (CRD) experiment was applied in triplicates to evaluate the effect of sur-factant (0, 0.2, 0.4 and 1% lecithin with 0.2% Tween 80 as control) and calcium chlo-ride solution (100 and 200 mL) on the microencapsulation process yield of microen-capsulated Lactobacillus casei. Microsphere characterization was performed by scan-ning electron microscopy (SEM). The microencapsulation process yield increased with increasing the volume of calcium chloride solution and it decreased with increasing the amount of lecithin. The highest microencapsulation process yield was obtained when 0.2% Tween 80 was used as surfactant. The shape of beads was spherical and their mean diameter was 17.80±3.55 μm.
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... In the large scale application of intermediate product of alginate known as alginic acid has restricted stability due to unsatisfactory of mechanical strength. A stable watersoluble alginate product can be obtained by transforming alginic acid into a range of commercial alginate by incorporating with different salts [68]. Thereafter alginate could be able to stimulate biocompatible, renewable, biodegradable and hydrogel in the form of cation divalent [69]. ...
... Thereafter alginate could be able to stimulate biocompatible, renewable, biodegradable and hydrogel in the form of cation divalent [69]. such as Na-, K-, NH 4 -, Mg-, and Ca- [68] and therefore can be used as an adsorbent material. The chemical or physical modification of alginate to fabricate composite material significantly enhances the applicability of adsorption, mechanical strength and toughness as well as improvises the physical properties of alginate [70]. ...
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Thesis
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Chapter
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Food Emulsions: Principles, Practice, and Techniques, Second Edition introduces the fundamentals of emulsion science and demonstrates how this knowledge can be applied to better understand and control the appearance, stability, and texture of many common and important emulsion-based foods. Revised and expanded to reflect recent developments, this second edition provides the most comprehensive and contemporary discussion of the field of food emulsions currently available. It contains practical information about the formulation, preparation, and characterization of food emulsions, as well as the fundamental knowledge needed to control and improve food emulsion properties. New features include updates of all chapters, a critical assessment of the major functional ingredients used in food emulsions, and reviews of recent advances in characterizing emulsion properties.
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