Effects of gellan gum and inulin on mixed‐gel properties and molecular structure of gelatin

Abstract

Gellan gum (GG) is often added to gelatin (GL) to improve the gel property. GG‐based or inulin (IL)‐based hydrogels were developed. Rigid and brittle gels or smooth and delicate gels were prepared with GG and IL, respectively. This study aimed to explore the properties and interaction mechanisms of the mixed‐gel system containing GL, GG, and IL, in which different ratios of GG‐IL (0.4%) (10:0, 8:2, 6:4, 5:5, 4:6, 2:8, and 0:10) were added to GL (6%). Texture profiles, rheological properties, water mobility, intermolecular forces, circular dichroism (CD) spectra, and microstructures were analyzed. The results showed that addition of GG‐IL could improve the hardness, chewiness, and cohesiveness of mixed‐gel, besides maintaining appropriate springiness. Water mobility of the mixed‐gel decreased while viscoelasticity increased upon the addition GG. At GG:IL = 2:8, the melting temperature of mixed‐gel was far higher than that of GL gel itself. The GL‐GG‐IL gel showed decrease in nonspecific bonding and increase in hydrogen bonding compared with the GL gel. CD spectra indicated the promotion of GL unfolding by GG, hence suggesting the binding of GG to GL; binding ability was better at GG:IL >5:5. Cryo‐SEM provided evidence for the formation of cross‐linked network within GL‐GG‐IL. Overall, we concluded that addition of GG‐IL to GL system would be most suitable for improving the properties of mixed‐gel. This finding may be potentially applicable in the further development of gel food products, such as meat jellies and gummy jellies.

Progress in the Preparation and Application of Inulin-Based Hydrogels

“…These mechanisms protect the drug from degradation in the upper gastrointestinal tract and ensure controlled release at the targeted site, such as the colon. The release mechanism of the drug can be affected by various factors, including the composition of the hydrogel, the molecular weight of the drug, the degree of crosslinking, and the environmental conditions [ 27 , 89 , 93 ]. Norsyazwani Solehah Norudin et al also investigated the mechanism of the controlled pH-sensitive release of inulin-based hydrogels.…”

Preparation of Novel Flaxseed Oil/Beeswax Oleogel Systems and Its Application in the Improvement of Sodium Alginate Films

“…Glycerol, as a plasticizer, can break the original structure of polysaccharide polymer and form new hydrogen bonds, thus enhancing plasticity. According to Wang, Wang, Wang, and Wang [17], different plasticizers had different effects on the properties of different substrates, and the appropriate addition of glycerol can improve the mechanical and barrier properties of the film. This phenomenon may be due to the relatively small molecular weight of glycerol, which contains more hydroxyl groups so that it has a good hydrophilicity.…”

Influence of Different pH Values on Gels Produced from Tea Polyphenols and Low Acyl Gellan Gum

“…As shown in Figure 4, the systems exhibited high viscosity at low shear rates, followed by a linear decrease in viscosity with the increasing shear rate, exhibiting a typical shear thinning behavior and indicating that the TP-LGG compound gel solutions were non-Newtonian fluids. The shear thinning behavior between TPs and LGG was mainly attributed to the destruction of intramolecular or intermolecular interactions [25,26] which caused a decrease in intermolecular electrostatic repulsion and an increase in mutual aggregation. At the same shear rate, the viscosity decreased as the pH increased from 3 to 9, and the viscosity of the compound gel solution was the highest at pH 3.…”

“…The parameters of the tests were set as follows: measure type, TPA; probe type, P/50; compression strain, 50%; pretest speed, 5.0 mm/s; test speed, 1.0 mm/s; and post-test speed, 5.0 mm/s. Based on the characteristics of the samples, data on hardness (g) and springiness (g) were recorded and used as the analysis index [25]. The steady rheology was tested as previously described [35,36], with some modifications.…”