Food Chemistry 266 (2018) 545–550
Contents lists available at ScienceDirect
Food Chemistry journal homepage: www.elsevier.com/locate/foodchem
Influence of cyclodextrins on the gel properties of kappa-carrageenan Chao Yuan a b
a,b,⁎
b
a,b
, Luyuan Sang , Yanli Wang
, Bo Cui
a,b,⁎
T
State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China School of Food Science and Engineering, Qilu University of Technology, Shangdong Academy of Sciences, Jinan 250353, China
A R T I C LE I N FO
A B S T R A C T
Keywords: κ-Carrageenan Cyclodextrins Gelation Rheology Scanning electronic microscope Model
The influence of cyclodextrins (CDs) on the rheological and structural properties of κ-carrageenan (κ-CA) gel was investigated. Gelling temperature (Tg) of κ-CA was improved by CDs present in the system. Variation of the Herschel-Bulkley model parameters indicates that the addition of CDs increases plasticity of the κ-CA sol. Scanning electronic micrographs show that networks of κ-CA become flat and firm after CDs were added. κ-CA gel containing methyl-β-CD shows the most uniform and fine network structure. Moreover, a proposed model of CDs in κ-CA phase was provided. The influence of CDs on κ-CA gelation was mainly through (i) the exclusion of CDs from κ-CA in the sol state, (ii) the regular rearrangement of κ-CA random coils influenced by CDs in the sol state, (iii) the binding of CDs to the κ-CA surface by hydrogen bonds in the gel.
1. Introduction Carrageenan (CA) is the generic name for a family of high molecular weight viscosifying polysaccharides that are extracted from certain species of red seaweeds in the family Rhodophyceae formed by alternate units of D-galactose and 3,6-anhydro-galactose (3,6-AG) joined by α-1,3 and β-1,4-glycosidic linkage (Coviello, Matricardi, Marianecci, & Alhaique, 2007; Necas & Bartosikova, 2013; Zia et al., 2017). CA is a sulfated polygalactan containing 15–40% sulfate groups, which makes it an anionic polysaccharide (Zia et al., 2017). The three major forms of CA are κ-, λ- and ι-CA, only κ-CA and ι-CA possess gelling capability. CA is currently used primarily as a gelling, stabilizing and thickening agent in food industry, especially in milk products (McKim, 2014). They are also used in cosmetics, pharmaceutical and textile formulations, as well as in the printing industry (Prajapati, Maheriya, Jani, & Solanki, 2014). κ-CA is known to form a thermo-reversible gel as a function of temperature and gel inducing agents (cations such as K+ and Ca+). It has the same basic linear primary structure as other CAs. However, it contains one sulfate group per disaccharide unit at carbon 2 of the 1,3 linked galactose unit. By cooling or increasing cationic concentrations, the gelation of κ-CA solutions occurs as a result of coil-to-helix conformational transition and the ensuing aggregation between the ordered helices (Morris, Rees, & Robinson, 1980). This process has been generally reported as a “domain model” based on the presence of double helices in the cross-linking zones of the gel network. According to the “domain model”, gelation of κ-CA initiates when cooling the solution below a so called coil-helix transition temperature (Tch) that induces the formation of double helices. While κ-CA gel transforms ⁎
from double helices to random coils in solution heating above a so called helix-coil transition temperature (Thc). When cations are present, adjacent double helices aggregate to generate long-range cross-linking, which can lead to the formation of a gel (Campo, Kawano, Silva, & Carvalho, 2009). The charges exist on the CA helices with its negative sulfate groups oriented towards their external part generating the electrostatic repulsion between helices (Piculell, 2006; Takemasa & Nishinari, 2004). In contrast certain anions like iodide bind specifically to the CA helix resulting in an increase in the overall charge density along the helical chains and hence inhibiting helix aggregation. Hence, ions depend on a thermal reversible gel containing large amounts of water, with weak water holding properties and easy spontaneous fluid release (Ako, 2015). The phenomenon of water release from gels is called syneresis and is defined as the spontaneous contraction of a gel without application of external forces, resulting in the expulsion of liquid (Scherer, 1989). Shrinkage behaviour has attracted significant interest in the field of food and biomedical applications, including drug delivery systems (Zhang et al., 2018; Ako, 2015; Defreitas, Sebranek, Olson, & Carr, 1997; Thrimawithana, Young, Dunstan, & Alany, 2010). It often has adverse effects on food, manifesting as a degradation of sensory quality (Tao et al., 2018). In recent years, sugars have been exploited widely to enhance κ-CA gelation and gel stability (Lascombes et al., 2017; Loret, Ribelles, & Lundin, 2009; Stenner, Matubayasi, & Shimizu, 2016). It was reported that sugars bind directly to κ-CA, increasing the number of junction zones, with shorter average length. This is attributed to the stabilization of the κ-CA network by forming intermolecular, crosslinking hydrogen bonds between the OH-groups of the sugar and κ-CA
Corresponding authors at: School of Food Science and Engineering, Qilu University of Technology, Jinan 250353, China. E-mail addresses:
[email protected] (C. Yuan),
[email protected] (B. Cui).
https://doi.org/10.1016/j.foodchem.2018.06.060 Received 21 February 2018; Received in revised form 20 May 2018; Accepted 12 June 2018 Available online 15 June 2018 0308-8146/ © 2018 Elsevier Ltd. All rights reserved.
Food Chemistry 266 (2018) 545–550
C. Yuan et al.
used in the test. Sample was laid on the bottom plate and heated up to 60 °C. After loading the sample, the surface was covered with a thin layer of silicone oil to avoid water evaporation. The angular frequency range was from 0.1 rad/s to 100 rad/s and the constant strain was 1%. All rheological measurements were performed in duplicate except the frequency sweeps were in triplicate for statistical analysis and the samples were randomized for the analysis.
(Nishinari & Watase, 1992; Oakenfull, 2000). Cyclodextrins (CDs) are a series of cyclic oligosaccharides, which consists of α-1,4-linked α-Dglucopyranose units with an internal hydrophobic cavity and a hydrophilic exterior. Practically relevant CDs comprise six, seven or eight glucose units and are denoted α-, β- and γ-CDs, respectively (Szente, Szemán, & Sohajda, 2016; Yuan, Liu, & Liu, 2015). The effect of CDs on the rheological properties and ageing of a complex hydrogel system (Carbopol 974 and Natrosol) has been reported before (Mourtas, Aggelopoulos, Klepetsanis, Tsakiroglou, & Antimisiaris, 2009). It was found that the elastic properties of the hydrogels were strengthened at the presence of 400 mg/ml CD and the gels were almost insensitive to ageing. In our previous research, positive influence on texture characteristics and freeze-thaw stability of κ-CA after CDs were added into the gel systems was observed in detail (Yuan, Du, Zhang, Jin, & Liu, 2016). The syneresis was significantly prevented by CDs existing in κCA gel networks. Recently rheology and microstructure studies of hydrocolloid composites has become an interesting point in gel food research (Lascombes et al., 2017; Liu et al., 2017; Qiu et al., 2015). Obviously, CDs also can impact the κ-CA structures and rheological characteristics by intermolecular interaction. However, to extent of our knowledge, there is no comprehensive study devoted to the influence of CDs on the rheological properties of κ-CA gel or other common polysaccharide gels. Thus, the aim of the present study was to focus on the rheological and structural aspects of κ-CA gel influenced by 3 native CDs and 2CD derivatives to draw a reasonable conclusion based on measurements of rheological properties, gel-melting temperatures and scanning electron microscope (SEM) observations.
2.4. Microstructure The microstructure analysis of the gels was carried out on a JEOL 6610 scanning electron microscope (Akishima, Japan) at an acceleration voltage of 3 kV. 1% (w/w) κ-CA aqueous solution containing 0.2% (w/w) KCl and 3% (w/w) CDs was generated to obtain gel samples for the SEM test according to the Section 2.2. The gel samples were initially cured for 6 h at 4 °C before the blocks were cut into uniform cubes (∼1 cm3) by a sharp scalpel. The cubes of gel were quickly frozen by liquid nitrogen to avoid water migration and then the frozen gel cubes were quickly cut into smaller pieces (about 0.4 cm3) before the sample softened. The samples were put into an ultra-cold storage freezer for 2 h and then transferred to a freeze dryer and dried. Obtained porous solid samples were sputter coated with gold and viewed under high-vacuum. 2.5. Statistical analysis The data obtained in the Herschel-Bulkley model fitting were expressed as means of triplicate determinations. Statistical significance was assessed by Duncan’s new multiple range test with the level of significance set at p ≤ 0.05 using SPSS Statistics Version 22.0 software for Windows.
2. Materials and methods 2.1. Materials
3. Results and discussion
κ-CA was purchased from Tokyo Chemical Industry (Tokyo, Japan), α-, β-, and γ-CD, hyrdoxypropyl-β-cyclodextrin (HP-β-CD, MW: ∼1460) and methyl-β-cyclodextrin (M-β-CD, MW: ∼1310) used in this study were purchased from Sigma-Aldrich (Shanghai, China). KCl was purchased from Sinopharm (Beijing, China).
3.1. Rheological properties of κ-CA gels Fig. 1. shows rheological results of temperature sweep for 1% κ-CA with 0.4 g/l β-CD added through the cooling stages. Initial G′ is lower than G″, then from about 40 °C, both G′ and G″ increase rapidly and then G′ surpasses G″ which indicates that the system gelled. Initially, random and disorderly strings predominate in κ-CA sol, along with temperature reduction, single helices form and gather into double helices, then the double helices aggregate to higher ordered assemblies assisted with cations to create a three-dimensional gel network (Tari, Kara, & Pekcan, 2009). The temperature at the intersection point of G′ and G″ is regarded as the gelling temperature (Tg). This point indicates the gel begins to form when the temperature of the sol drops continuously. Tg results of κ-CA (1%) in which 0.1 to 0.6 g/l of different CDs were added are shown in Fig. 2. The Tg of single κ-CA (control) is
2.2. Sample preparation κ-CA (1%, w/w) was added to 0.2% (w/w) KCl aqueous solution, stirring for 20 min at 40 °C to let the polysaccharide swell, then CD was added in proportions and the mixture was heated up to 90 °C, and kept stirring for 30 min to form a homogeneous sol. The obtained solution was stood for 5 min to let the bubbles vent. The gel sample was formed by pouring the hot sol into a 50 ml beaker and cooled in 20 °C water. Before tests, the samples were stood for 6 h. 2.3. Rheological measurement The rheological property measurements were performed on an MCR102 rheometer (Anton Paar, Austria). For temperature sweeps of dynamic rheology measurement, a CC24 concentric cylinder measuring system was selected. The equilibrated sample was transferred directly into the test cell using a spoon, then the sample was heated up to 80 °C. After the gel transformed to liquid, the sample was covered by a low viscosity silicone oil to prevent solvent evaporation. The solution was kept at 80 °C for 5 min to destroy all possible helical structures. Measurement was performed at a strain of 0.5% and a frequency of 1 Hz within the linear viscoelastic region with the temperature reduction from 80 °C to 25 °C at a constant rate of 2 °C/min. The elastic/storage modulus (G′) and viscous/loss modulus (G″) were recorded for all samples and the gelling temperature (Tg) was obtained by the point of intersection of G′ and G″ (i.e. tan δ = G″/G′ = 1). For frequency sweeps, a parallel plate geometry (diameter 50 mm, gap 1 mm) was
Fig. 1. Temperature sweep of the κ-CA/β-CD gel system. 546
Food Chemistry 266 (2018) 545–550
C. Yuan et al.
Fig. 2. The effect of cyclodextrins on the gel temperature of κ-CA. Fig. 3. Apparent viscosity – shear rate plot for κ-CA gels containing CDs.
38.66 °C. Most of the samples in which CDs were added have a higher Tg than the control sample. CDs adjusted the gel formation and made it easier to form gel at a higher gelling temperature. In the κ-CA sol, random coils more easily rearrange in the presence of CDs. As regards concentration, the Tg of κ-CA first rises and then drops as an increasing amount of CD is added. The optimal addition amount for β-CD, HP-βCD and M-β-CD is 0.3 g/l, while α- and γ-CD is 0.5 g/l. Concerning the variety of CDs, the influence of β-CD is the most significant at low concentrations (≤0.3 g/l) among the 3 native CDs, and α-CD is the highest at high concentrations (> 0.3 g/l). β-CD easily forms intramolecular hydrogen bonds (Szejtli, 2013) and this causes its solubility to be lower in water than α- and γ-CDs. However, during the temperature dropping process the β-CD separated out and aggregated, this may have higher influence on the phase transformation of κ-CA and lead the gel formation at higher temperature. On the other hand, the aggregation of β-CD increases heterogeneity of the system and resulted in influence reduction at high concentrations, while the more highly soluble α- and γ-CD serve this purpose. In addition, derivatives have greater influence on Tg than native β-CD, especially M-β-CD. The outstretched substituent groups of M-β-CD improve the ability to smooth κCA random coils. It was recently reported that the Tg of a κ-CA sample (1.5%, w/w) prepared by an ion exchange method in K+ solution was 31 °C, and the gel system containing K+ ions together with Mg2+ or Ca2+ ions showed lower Tg (Robal et al., 2017). In the food industry, the gelling temperature has significant meaning for food process and storage, high Tg helps save energy consumption and improve the storage stability. The addition of CDs improved the Tg hinting that CDs influenced the gelling process of κ-CA. The influence is likely to occur in κ-CA sol phase. To demonstrate the influence, κ-CA/CDs mixture gels (1% κ-CA and 3% CDs, w/w) were heated up to 60 °C letting the gel thaw and their steady rheological characteristics were investigated. The flow curves of the κ-CA/CDs gels at 60 °C are shown in Fig. 3. The apparent viscosity – shear rate curves clearly reveal that the apparent viscosity values of all samples decrease with the increase of shear rate indicating that these mixed solutions are shear thinning in nature. The viscosities form an inflection point at around 10 s−1 below which the viscosities drop sharply along with the increase of shear rate, above which they remain constant and low. However, the presence of CDs in the sol significantly changed the apparent viscosity of κ-CA, and the viscosity of mixture sols are higher than single κ-CA. The influences of three native CDs are lesser than that of HP-β-CD and M-β-CD. The substituent groups open the intramolecular hydrogen bond of β-CD that improves the water solubility of β-CD dramatically (Szente & Szejtli, 1999). Moreover, the outstretched substituent groups increased their
interaction force toward κ-CA random coils, leading to a more regular rearrangement of κ-CA in the shear direction that reduced the apparent viscosity of the systems. As evident from Fig. 3, the flow type of κ-CA/CDs sols is nonNewtonian and pseudo plastic. The experimental data points were fitted to the Herschel-Bulkley model (Eq. (1)).
μa = τ0·γ −1 + k·γ n − 1
(1)
where μa is the apparent viscosity (Pa·s), τ0 is the yield shear stress (Pa), k is the consistency coefficient (Pa·sn), γ is the shear rate (s−1) and n is the flow behavior index (dimensionless) (Chen, Huang, Wang, Li, & Adhikari, 2016). The experimental apparent viscosity versus shear rate data were fitted well with Eq. (1) with the coefficient of determination values R2 > 0.999. The values of τ0, k and n obtained through the Herschel-Bulkley model are provided in Table 1. The tabulated data show that the yield stress (τ0) decreases when CD exists in the κ-CA sol, and the change is significant (p < 0.05). It indicates that CDs let the κ-CA more easily begin to flow plastically. The consistency coefficient k, which is related to the apparent viscosity of the materials in the entire shear rate range, is significantly (p < 0.05) decreased by the addition of CDs. The magnitude of n is < 1 in all samples, confirming that the κ-CA/CDs mixture sols are shear thinning in nature. The lower n values indicate stronger dependence of apparent viscosity on shear rate. The n value of κ-CA/M-β-CD sol is the highest among the tested samples (Table 1). This suggests that the addition of M-β-CD increases the shear sensitivity of κ-CA sol. The variation of Hershel-Bulkey model parameters suggests that the addition of CDs increases the plasticity of the κ-CA sol. κ-CA is a macromolecule with an average relative molecular mass well above 100 kDa, while CDs are a series of cyclic small molecules with truncated cone shapes, and relative molecular masses from 973 to about 1500. The CDs distribute among the linear κ-CA solution, during stir, they cause the rearrangement of κ-CA random coils, leading to a more even distribution of κ-CA molecules in water. The molecules can easily form double helices and aggregate when the system temperature drops to gelling temperature and changes the gel properties of κ-CA. 3.2. Microstructure analysis Further information about the microstructure of the gels was obtained from scanning electron microscopy (SEM). Rapid freezing with liquid nitrogen employed in SEM reduces the water migration and ice crystal formation and preserves the spatial structure of these highly aqueous systems for further investigation (Thrimawithana et al., 2010). 547
Food Chemistry 266 (2018) 545–550
C. Yuan et al.
Table 1 Hershel-Bulkey model parameters of κ-CA/CDs gel mixtures. Samples
τ0 (Pa)
κ-CA κ-CA/α-CD κ-CA/β-CD κ-CA/γ-CD κ-CA/HP-β-CD κ-CA/M-β-CD
0.3585 0.2408 0.2009 0.1974 0.2155 0.2175
K (Pa·s) ± ± ± ± ± ±
0.0064d 0.0022c 0.0033a 0.0010a 0.0017b 0.0018b
0.1653 0.1203 0.1228 0.0705 0.0118 0.0567
R2
n ± ± ± ± ± ±
0.0019f 0.0018d 0.0017e 0.0005c 0.0004a 0.0006b
0.9294 0.9242 0.9597 0.9637 0.9124 0.8118
± ± ± ± ± ±
0.0006d 0.0002c 0.0008e 0.0003f 0.0013b 0.0010a
0.9995 0.9999 0.9999 0.9999 0.9997 0.9992
Mean ± SD values in each column with a different superscript letter are significantly different (p ≤ 0.05).
Fig. 4. Scanning electronic micrographs of freeze-dried κ-CA and κ-CA/CDs mixture gels: κ-CA gel (a); κ-CA/α-CD gel (b); κ-CA/β-CD gel (c); κ-CA/γ-CD gel (d); κCA/HP-β-CD gel (e); κ-CA/M-β-CD gel (f). Graphs with ' are profile of corresponding samples. Magnification of the images are all 200×.
and there are a large amount of β-CD crystals on the gel wall. The results support the point that the κ-CA/β-CD mixture sol has a higher apparent viscosity than other κ-CA/CD mixtures. κ-CA gels containing HP-β-CD and M-β-CD show a fine network with uniform pores (Fig. 4e and f), in addition, κ-CA fragments distribute in the pores (Fig. 4e' and f'). The special structures explain the higher gelling temperatures and lower apparent viscosities and make contributions to the stability of the gel systems by water holding and structure support. By contrast, the κCA/M-β-CD gel mixture shows more uniform and fine network structure. A number of hypotheses have been proposed regarding how cosolvents (sugars and polyols) affect the gelation of κ-CA: (i) the
Considerable differences in SEM images of the κ-CA/CDs systems were observed (Fig. 4). The concentration of the κ-CA is 1% (w/w) in all the samples and the concentration of CDs is 3% (w/w). κ-CA gel displays the appearance of a cross-linked network structure with wrinkles (Fig. 4a and a' for profile). Obviously, it is a relatively low strength and flexible structure. A similar κ-CA structure had been observed by (Farahnaky, Azizi, Majzoobi, Mesbahi, & Maftoonazad, 2013). The wall of the networks became flat and firm after the CDs were added. Furthermore, there are many strands or fragments linked among the walls. For the 3 native CDs, γ-CD helps κ-CA to form the narrowest meshed network (Fig. 4d), while κ-CA/α-CD forms the network with the largest mesh (Fig. 4b). The gel network of κ-CA/β-CD is non-uniform (Fig. 4c) 548
Food Chemistry 266 (2018) 545–550
C. Yuan et al.
Fig. 5. Schematic representation of the domain model of gelling process of κ-CA gel presenting (upper) or absenting (lower) CDs (κ-CA network, line; CD, polygon; potassium ion, dot).
4. Conclusion
enhancement of the water structure around polysaccharides, and the concurrent change in polysaccharide hydration, induced by the cosolvent (Nishinari & Watase, 1992; Oakenfull, 2010); (ii) exclusion of cosolvents from polysaccharide surfaces (Shimizu & Matubayasi, 2014); (iii) binding between sugars/polyols and polysaccharides in the gel phase (Loret et al., 2009). The above hypotheses have been investigated by the statistical thermodynamic theory of gelation, derived from the rigorous Kirkwoode – Buff theory (Stenner et al., 2016). The results suggested that (i) the exclusion of sugars and polyols from κ-CA surfaces in the sol state and (ii) the binding of sugars and polyols to κ-CA in the gel are the two main driving forces in κ-CA sol – gel transformation. However, CDs are cyclic oligosaccharides, their structures and molecular weights are different from sugars and polyols, and the size of CDs is also larger than sugars. According to the above observations, and the rheology and SEM results in this study, a proposed model of CDs in the κ-CA phase and the gelling processes are depicted in Fig. 5. The drawing is based on the former reports about the structure and model of the κ-CA gel (Shimizu & Matubayasi, 2014; Stenner et al., 2016; Weiner, 2014). As shown in Fig. 5, the presence of CDs in the κ-CA sol system contributes to the regular arrangement of κ-CA random coils, under stirring, to form more double helices and finally forming a fine network (Fig. 4b–f). On the other hand, the κ-CA sol is still a little disordered after stirring, in the absence of CDs, and produces fewer double helices, finally forming a wrinkled network (Fig. 5). The influence of CDs on the formation of a κ-CA gel mainly occurs in the sol state. After the gel has formed, CDs bind to the surface of the κ-CA double helices, improving the gel strength and stability and reducing the syneresis. These results have been reported in our former study about the influence of CDs on the texture and freeze-thaw stability of κCA (Yuan et al., 2016). To summarize, considering the structure different with sugars, the influence of CDs on the gelation of κ-CA is mainly through (i) the exclusion of CDs from κ-CA surfaces in the sol state, (ii) the regular rearrangement of κ-CA random coils under stirring in the presence of CDs in the sol state, (iii) the binding of CDs to the κ-CA surface by hydrogen bonds in the gel. For the special structure of CDs, their influence on gel properties and stability of κ-CA is greater than sugars. In addition, some designed functionality may be realized if CDs encapsulate bioactive compounds or nutriments, and are included in the κ-CA gel system.
CDs are a series of cyclic oligosaccharides owning special size, structure and properties. This work investigated the influence of CDs on the rheological and structural aspects of κ-CA gels. CDs adjusted the gel formation and made it easier to form at a higher Tg. Tg attains the highest values with β-CD, HP-β-CD and M-β-CD at 0.3 g/l, α- and γ-CD at 0.5 g/l. CD derivatives have greater influence on Tg than native β-CD, especially M-β-CD. The flow curves indicate that κ-CA/CD mixture sols are on a non-Newtonian and pseudo plastic fluid. The apparent viscosites of mixture sols are higher than single κ-CA. The influences of three native CDs are lesser than that of HP-β-CD and M-β-CD. The experimental data points were fitted to the Herschel-Bulkley model. Yield stress (τ0) and consistency coefficient (k) decrease when CD exists in the κ-CA sol, the magnitude of n is < 1 in all samples. The change of Hershell-Bulkey model parameters shows that the addition of CDs increases the plasticity of the κ-CA sol. It causes the rearrangement of κCA random coils and changes the gel properties of κ-CA. Moreover, considerable differences in SEM images of the κ-CA/CDs systems were observed. κ-CA gel displays the appearance of a cross-linked network structure with wrinkles. The wall of the networks became flat and firm after the CDs were added, furthermore, there are many strands or fragments linked among the walls. By contrast, κ-CA gels containing Mβ-CD showed the most uniform and fine network structure. Based on the rheology and SEM results, a proposed model of CDs in the κ-CA phase and the gelling processes was provided. The influence of CDs on the κ-CA gelation is suggested mainly through (i) the exclusion of CDs from κ-CA surfaces in the sol state, (ii) the regular rearrangement of κ-CA random coils under stirring in the presence of CDs in the sol state, (iii) the binding of CDs to the κ-CA surface by hydrogen bonds in the gel. For the special structure of CDs, their influence on gel properties and stability of κ-CA is interesting. Furthermore, some designed functionality will be realized if CDs encapsulate bioactive compounds or nutriments and are included in the κ-CA gel system.
Acknowledgement This work was supported by the National Natural Science Foundation of China, China (Grant no. 31571881) and Taishan Scholars Program of Shandong Province, China.
549
Food Chemistry 266 (2018) 545–550
C. Yuan et al.
Conflict of interest statement
Oakenfull, D. (2010). Solvent structure and gelation of polysaccharides in concentrated solutions of simple sugars. In P. A. Williams, & G. O. Phillips (Vol. Eds.), Special publication-royal society of chemistry: 251, (pp. 277–284). Cambridge: The Royal Society of Chemistry. Piculell, L. (2006). Gelling carrageenans. In A. M. Stephen (Ed.). Food polysaccharides and their applications (pp. 205–243). New York: Marcel Dekker. Prajapati, V. D., Maheriya, P. M., Jani, G. K., & Solanki, H. K. (2014). Carrageenan: A natural seaweed polysaccharide and its applications. Carbohydrate Polymers, 105, 97–112. Qiu, S., Yadav, M. P., Chen, H., Liu, Y., Tatsumi, E., & Yin, L. (2015). Effects of corn fiber gum (CFG) on the pasting and thermal behaviors of maize starch. Carbohydrate Polymers, 115, 246–252. Robal, M., Brenner, T., Matsukawa, S., Ogawa, H., Truus, K., Rudolph, B., & Tuvikene, R. (2017). Monocationic salts of carrageenans: Preparation and physico-chemical properties. Food Hydrocolloids, 63, 656–667. Scherer, G. W. (1989). Mechanics of syneresis I. Theory. Journal of Non-crystalline Solids, 108(1), 18–27. Shimizu, S., & Matubayasi, N. (2014). Gelation: The role of sugars and polyols on gelatin and agarose. Journal of Physical Chemistry B, 118(46), 13210–13216. Stenner, R., Matubayasi, N., & Shimizu, S. (2016). Gelation of carrageenan: Effects of sugars and polyols. Food Hydrocolloids, 54, 284–292. Szejtli, J. (2013). Cyclodextrin Technology. Berlin: Springer Science & Business Media. Szente, L., & Szejtli, J. Z. (1999). Highly soluble cyclodextrin derivatives: Chemistry, properties, and trends in development. Advanced Drug Delivery Reviews, 36(1), 17–28. Szente, L., Szemán, J., & Sohajda, T. (2016). Analytical characterization of cyclodextrins: History, official methods and recommended new techniques. Journal of Pharmaceutical and Biomedical Analysis, 130, 347–365. Takemasa, M., & Nishinari, K. (2004). The effect of the linear charge density of carrageenan on the ion binding investigated by differential scanning calorimetry, dc conductivity, and kHz dielectric relaxation. Colloids and Surfaces B: Biointerfaces, 38(3–4), 231–240. Tao, H., Huang, J., Xie, Q., Zou, Y., Wang, H., Wu, X., & Xu, X. (2018). Effect of multiple freezing-thawing cycles on structural and functional properties of starch granules isolated from soft and hard wheat. Food Chemistry, 265, 18–22. Tari, Ö., Kara, S., & Pekcan, Ö. (2009). Critical exponents of kappa carrageenan in the coil-helix and helix-coil hysteresis loops. Journal of Macromolecular Science, 48, 812–822. Thrimawithana, T. R., Young, S., Dunstan, D. E., & Alany, R. G. (2010). Texture and rheological characterization of kappa and iota carrageenan in the presence of counter ions. Carbohydrate Polymers, 82(1), 69–77. Weiner, M. L. (2014). Food additive carrageenan: Part II: A critical review of carrageenanin vivo safety studies. Critical Reviews in Toxicology, 44(3), 244–269. Yuan, C., Du, L., Zhang, G., Jin, Z., & Liu, H. (2016). Influence of cyclodextrins on texture behavior and freeze-thaw stability of kappa-carrageenan gel. Food Chemistry, 210, 600–605. Yuan, C., Liu, B., & Liu, H. (2015). Characterization of hydroxypropyl-β-cyclodextrins with different substitution patterns via FTIR, GC–MS, and TG–DTA. Carbohydrate Polymers, 118, 36–40. Zhang, B., Bai, B., Pan, Y., Li, X., Cheng, J., & Chen, H. (2018). Effects of pectin with different molecular weight on gelatinization behavior, textural properties, retrogradation and in vitro digestibility of corn starch. Food Chemistry, 264, 58–63. Zia, K. M., Tabasum, S., Nasif, M., Sultan, N., Aslam, N., Noreen, A., & Zuber, M. (2017). A review on synthesis, properties and applications of natural polymer based carrageenan blends and composites. International Journal of Biological Macromolecules, 96, 282–301.
We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled. References Ako, K. (2015). Influence of elasticity on the syneresis properties of κ-carrageenan gels. Carbohydrate Polymers, 115, 408–414. Campo, V. L., Kawano, D. F., Silva, D. B. D., Jr., & Carvalho, I. (2009). Carrageenans: Biological properties, chemical modifications and structural analysis – A review. Carbohydrate Polymers, 77(2), 167–180. Chen, C., Huang, X., Wang, L., Li, D., & Adhikari, B. (2016). Effect of flaxseed gum on the rheological properties of peanut protein isolate dispersions and gels. LWT – Food Science and Technology, 74(Supplement C), 528–533. Coviello, T., Matricardi, P., Marianecci, C., & Alhaique, F. (2007). Polysaccharide hydrogels for modified release formulations. Journal of Controlled Release, 119(1), 5–24. Defreitas, Z., Sebranek, J. G., Olson, D. G., & Carr, J. M. (1997). Freeze/thaw stability of cooked pork sausages as affected by salt, phosphate, pH, and carrageenan. Journal of Food Science, 62(3), 551–554. Farahnaky, A., Azizi, R., Majzoobi, M., Mesbahi, G., & Maftoonazad, N. (2013). Using power ultrasound for cold gelation of kappa-carrageenan in presence of sodium ions. Innovative Food Science & Emerging Technologies, 20(4), 173–181. Lascombes, C., Agoda-Tandjawa, G., Boulenguer, P., Le Garnec, C., Gilles, M., Mauduit, S., ... Langendorff, V. (2017). Starch-carrageenan interactions in aqueous media: Role of each polysaccharide chemical and macromolecular characteristics. Food Hydrocolloids, 66, 176–189. Liu, Y., Yadav, M. P., Chau, H. K., Qiu, S., Zhang, H., & Yin, L. (2017). Peroxidasemediated formation of corn fiber gum-bovine serum albumin conjugates: Molecular and structural characterization. Carbohydrate Polymers, 166, 114–122. Loret, C., Ribelles, P., & Lundin, L. (2009). Mechanical properties of κ-carrageenan in high concentration of sugar solutions. Food Hydrocolloids, 23(3), 823–832. McKim, J. M. (2014). Food additive carrageenan: Part I: A critical review of carrageenanin vitro studies, potential pitfalls, and implications for human health and safety. Critical Reviews in Toxicology, 44(3), 211–243. Morris, E. R., Rees, D. A., & Robinson, G. (1980). Cation-specific aggregation of carrageenan helices: Domain model of polymer gel structure. Journal of Molecular Biology, 138(2), 349–362. Mourtas, S., Aggelopoulos, C. A., Klepetsanis, P., Tsakiroglou, C. D., & Antimisiaris, S. G. (2009). Complex hydrogel systems composed of polymers, liposomes, and cyclodextrins: Implications of composition on rheological properties and aging. Langmuir, 25(15), 8480–8488. Necas, J., & Bartosikova, L. (2013). Carrageenan: A review. Veterinarni Medicina, 58(4), 187–205. Nishinari, K., & Watase, M. (1992). Effects of sugars and polyols on the gel-sol transition of kappa-carrageenan gels. Thermochimica Acta, 206(Supplement C), 149–162. Oakenfull, D. (2000). Solvent structure and gelation of polysaccharides in concentrated solutions of simple sugars. In G. O. Phillips (Ed.). Gums and Stabilisers for the Food Industry (pp. 277–284). Woodhead Publishing A2 – Williams, Peter A.
550
