Xanthan gum inclusion optimizes the sol-gel and mechanical properties of agar/konjac glucomannan system for designing core-shell structural capsules. (January 2022)

• Record Type: Journal Article
• Authors: Tu, Wenyao; Shi, Wenjuan; Li, Hao; Wang, Yixin; Qiao, Dongling; Jiang, Fatang; Zhang, Binjia
• Is Part Of: Food hydrocolloids. Volume 122(2022)
• Publication Date: 2022-01
• Subjects: Konjac glucomannan -- Core-shell structural capsule -- Shell material -- Properties; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2021.107101
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: Core-shell structural capsules can encapsulate various food ingredients (e.g., nutrients), thus being highly potential for the design of many food products. This work reports how the gum (xanthan, locust bean or gellan) inclusion tailors the practical features of agar/konjac glucomannan (KGM) system for fabricating the core-shell structural capsules. The rheological and textural analyses revealed that xanthan gum inclusion could simultaneously increase the sol-gel transition point and gel strength (ca. 1.6 times higher) of agar/KGM system. The composite gels were dehydrated to generate shell materials. The materials including xanthan or locust bean gum showed stronger chain interactions than did that including gellan gum, accompanied by weakened crystalline features for the different shell materials. Again, compared to the agar/KGM counterpart, the shell materials including xanthan gum could display a similar tensile strength (close to 50 MPa) but an evidently increased elongation at break (ca. 2.5 times higher). Then, these agar/KGM based systems were used to prepare core-shell structural capsules. The capsules based on agar/KGM/xanthan gum materials exhibited the highest roundness and breaking stress. Regarding this, the increased sol-gel point reduced the time required for droplet hardening (to generate core-shell gel balls); such fact, together with the higher gel strength, weakened the deformation of gel balls and thus increased the roundness and breaking stress of capsules (resulting from drying of gel balls). Graphical abstract: Image 1 Highlights: Adding xanthan gum increased sol-gel point of agar/konjac glucomannan (KGM) system. Adding xanthan gum increased gel strength of agar/KGM based system. Adding xanthan gum increased elongation at break of agar/KGM based shell materials. Adding xanthan gum increased roundness of agar/KGM based core-shell capsules. Adding xanthan gum increased breaking stress of agar/KGM based core-shell capsules.