Gelling properties and lipid oxidation of kamaboko gels from grass carp (Ctenopharyngodon idellus) influenced by chitosan

Journal of Food Engineering 82 (2007) 128–134 www.elsevier.com/locate/jfoodeng

Gelling properties and lipid oxidation of kamaboko gels from grass carp (Ctenopharyngodon idellus) influenced by chitosan Linchun Mao *, Tao Wu Department of Food Science and Nutrition, College of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou 310029, China Received 6 December 2006; received in revised form 17 January 2007; accepted 21 January 2007 Available online 4 February 2007

Abstract Chitosan was applied to kamaboko gels made from grass carp (Ctenopharyngodon idellus), and the correlative influences on gelling quality and lipid oxidation were evaluated by color, texture, expressible water, TBA (2-thiobarbituric acid) and peroxide values. Whiteness, hardness, springiness, cohesiveness, chewiness, adhesiveness, TBA value increased, while expressible water and peroxide value decreased when 1% chitosan was added in gels. Addition with 1% chitosan was considered as a promising approach in the processing of grass carp gels to improve thermal gelling properties and delay lipid oxidation. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Chitosan; Grass carp; Kamaboko gel; Gelling property; Lipid oxidation

1. Introduction Grass carp (Ctenopharyngodon idellus) is one of the main freshwater fish species in China. The potential of this fish as a source of low fat, high protein food has not yet been fully utilized due to the limited processing, distribution sphere and storage period. Surimi is a high quality myofibrillar protein concentrate that obtained from fish muscle, with high commercial value and extensive application in seafood production. Therefore, surimi processing is the effective way to utilize those fish species with low commercial value. Functional properties such as color and texture are the major factors responsible for the final acceptance of surimi-based products by consumers. When high quality surimi is the predominant component of a surimi-based product, the resulting texture tends to be rubbery (Lee, Wu, & Okada, 1992). Another restriction of surimi products is the oxidation of lipid. Fish lipids are well known to have a high content of polyunsaturated fatty acids, such as eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) which have health promotion and cardiovascular *

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0260-8774/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.jfoodeng.2007.01.015

effects. But they are fairly susceptible to oxidation, leading to a number of complex chemical changes that eventually give rise to the development of off-flavors, as well as the generation of harmful oxidation products (Fritsche & Johnston, 1988; Hsieh & Kinsella, 1989; Shahidi, 1998). To better suit the textural and healthy preferences of consumers, natural ingredients is commonly added to surimi, to improve the functional properties and inhibit lipid oxidation of surimi products (Lee et al., 1992; Lee, Lee, Chung, & Lavery, 1992). Protein–carbohydrate interactions affects the functional properties in foods such as solubility, surface activity, conformational stability, gel forming ability, emulsifying and foaming properties, where proteins are the major ingredients, such as meat and fish processed products (Chin, Keeton, Longnecker, & Lamkey, 1998). Some biopolymers such as starch (Kim & Lee, 1987) and cellulose (Yoon & Lee, 1990) have been reported to contribute to surimi gel properties. Chitosan is a low-acetyl-substituted form of chitin, which has been reported to have a number of functional properties that make it technically and physiologically useful as a kind of dietary fibre (Shahidi, Arachchi, & Jeon, 1999; Jeon, Kamil, & Shahidi, 2002; Borderı´as, Sa´nchez-Alonso, & Pe´rez-Mateos, 2005). There have been

L. Mao, T. Wu / Journal of Food Engineering 82 (2007) 128–134

a few studies describing addition of chitosan to tofu (Kim & Han, 2002), meat products (Jo, Lee, Lee, & Byun, 2001; Lin & Chao, 2001; Sagoo, Board, & Roller, 2002) and fish muscle (Kataoka, Ishizaki, & Tanaka, 1998; Benjakul et al., 2000; Benjakul, Visessanguan, Phatchrat, & Tanaka, 2003; Kamil, Jeon, & Shahidi, 2002). A number of studies (Kamil et al., 2002; Shahidi, Kamil, Jeon, & Kim, 2002; Go´mez-Guille´n, Montero, Solas, & Pe´rez-Mateos, 2005) report that chitosan inhibits lipid oxidation, and that this inhibition is dependent on concentration and type of chitosan (different viscosity or molecular weight). As a natural polysaccharide material with texturizing properties (Benjakul et al., 2003), antioxidant activity (Kamil et al., 2002; Lin & Chou, 2004; Kim & Thomas, 2007) and antibacterial properties (Chung, Wang, Chen, & Li, 2003), chitosan therefore appears to be a promising use in fish surimi products to improve gelling properties and prevent lipid oxidation. The objective of this study was to investigate the effects of chitosan with different molecular weights and concentrations on the gelling properties and inhibition of lipid oxidation of kamaboko gels prepared from grass carp. 2. Materials and methods 2.1. Surimi and chemicals Fresh grass carp (C. idellus) was obtained from a fish market in Hangzhou, China. Fifty fresh fishes (ca. 50 kg) were washed and kept in ice until processing. Surimi was obtained after fishes were headed, gutted, and washed in cold water (below 10 °C), removing skin and bones. After dewatering with cheesecloth as filtering material, surimi was mixed with 8% sucrose as cryoprotectant, then packed into polyethylene bags (2 kg each), frozen at 70 °C in a ultra freezer (Forma Scientific R404A, USA) for 5 h and stored at 20 °C until needed. Commercial chitosans (MW 300 kDa and MW 10 kDa, 95% deacetylation) were obtained from Dingguo Bio-Technology Company (Hangzhou, China). All other chemicals used were of analytical grade and supplied by Sigma Company (Sigma Co., USA).

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2.2. Preparation of kamaboko gels Formulations of kamaboko gels are shown in Table 1. The frozen surimi was partially thawed at room temperature for approximately 2 h before being cut into 4 cm cubes. Surimi cubes were chopped for several minutes. First, salt (2%) was added and the mixture was chopped for 1.5 min, and then ice water was added and the mixture was chopped for 1 min, forming a very viscous and tacky paste. Starch (4%) and dried egg white (1%) were added and the mixture was chopped for another 4 min, then different chitosans (MW 300 kDa, MW 10 kDa, 1:1 mixture of MW 300 kDa and MW 10 kDa chitosans) were dispersed with a little 1% acetic acid and added to the mixture. The final concentrations of chitosan were 0.5% and 1%, respectively. The MW 300 kDa chitosan was described as relative high molecular weight chitosan (HC), the MW 10 kDa chitosan was described as relative low molecular weight chitosan (LC), their 1:1 mixture was described as HC + LC. All formulations were standardized at 78% moisture, 22% solids and 2% NaCl (Park, 2000). Gels without chitosan were served as control. The chopping procedure was carried out in a cool room (4 °C) to keep the paste below 8 °C. The mixture was extruded into plastic tubes (25 mm diameter, 120 mm length) where both ends were plugged with rubber pistons. The interior wall of the tubes was coated with a film of vegetable oil to prevent gel adhesion. The gel was cooked in a water bath at 90 °C for 20 min after setting at 25 °C for 3 h. After heating, surimi mixture became stronger and non-transparent gel, called kamaboko gel (Benjakul et al., 2000), which were removed from the tubes and stored at 4 °C in polystyrene bags, prior to measurements. 2.3. Proximate analysis Moisture, ash, and crude protein (N  6.25) were assayed as described by AOAC (1995). Lipid content was determined as described by Folch, Lee, and Sloane-Stanley (1957). The proximate analysis was based on the muscle of fresh grass carp.

Table 1 Experimental formula (grams) of kamaboko gels from grass carp Ingredients

Control

0.5% HC

1% HC

0.5% LC

1% LC

0.5% HC + LC

1% HC + LC

Surimi Ice water NaCl Egg white Starch HC LC Total

675 255 20 10 40 0 0 1000

660 265 20 10 40 5 0 1000

635 285 20 10 40 10 0 1000

660 265 20 10 40 0 5 1000

635 285 20 10 40 0 10 1000

660 265 20 10 40 2.5 2.5 1000

635 285 20 10 40 5 5 1000

HC: 300 kDa chitosan (high molecular weight chitosan); LC: 10 kDa chitosan (low molecular weight chitosan); HC + LC: mixture of HC and LC (1:1, w/ w). All formulations were standardized at 78% water and 22% solids.

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2.4. Color measurement Color measurements of gels were performed in a color meter (SPSIC WSC-S, China) at ambient temperature. The equipment was standardized with a standard-white reflection plate. The most important color parameter in surimi gels is whiteness, which was calculated using the formula: W = L – 3b, where L is the lightness from black to white, b is the scale from yellow to blue (Park, 1994). 2.5. Texture profile analysis Texture profile analysis (TPA) of gels was performed at ambient temperature with a TA-XT2i Texture Analyser (SMS, UK) and a 25 kg load cell. The Texture Expert Exceed version 1.22 computer program by Stable Micro System was used for data collection and calculation. Gels were cut in cylinders of 25 mm diameter  25 mm length. Each cylinder was compressed axially in two consecutive cycles of 25% compression, 5 s apart, with a flat plunger 50 mm in diameter (SMS-P/50). The cross-head moved at a constant speed of 1 mm/s. From the TPA curves, the following texture parameters were obtained: hardness at 25% of deformation, springiness, cohesiveness, adhesiveness, and chewiness (Pons, 1996).

5 ml of the distillate plus 0.6 ml of BHT (1 g/l) were added to 5 ml of 0.021 M TBA solution into a screw-cap test tube and heated in a water bath (90 °C) for 40 min for pink color development. The test tube was then cooled and the optical density was determined at 532 nm on a spectrophotometer (Spectrum-cn 722E, China) using control solution containing 5 ml distilled water, 5 ml TBA solution and 0.6 ml BHT. TBA values were expressed as mg of malondialdehyde (MDA) per kg of sample. The concentration of MDA was calculated from a standard curve using 1,1,3,3-tetraethoxy-propane (TEP) as the standard compound. 2.8. Peroxide value Gel samples (0.5 g) were mixed with 25 ml of a solution of glacial acetic acid and chloroform (3:2 v/v) in a conical flask, and then 1 ml of saturated potassium iodide was added. The mixture was kept in the dark for about 10 min, and then 30 ml of distilled water and 1 ml of freshly prepared 1% starch were added. After shaking, the samples were titrated with 0.01 M sodium thiosulfate. The peroxide values were expressed in units of meq/kg of sample (Egan, Kirk, & Sawyer, 1981). 2.9. Statistical analysis

2.6. Expressible water The amount of expressible water (EW) for each treatment was measured. Samples of 3 g (±0.2 g) of fish gels were weighed and put between two layers of filter paper. Samples were placed at the bottom of 50 ml centrifuge tubes and centrifuged at 1000g for 15 min at 15 °C (Uresti, Ramı´rez, Lo´pez-Arias, & Va´zquez, 2003). Immediately after centrifugation, the fish gel samples were weighed and the EW was calculated as: expressible water (%) = (Wi Wf)/Wi  100, where Wi is the initial weight of gel, Wf is the final weight of gel.

All analyses were run in triplicate for each replicate (n = 2  3). Results are reported as mean values of six determinations ± standard deviation (SD). Analysis of variance was performed by ANOVA procedures (SPSS 12.0 for Windows). Differences among the mean values of the various treatments and storage periods were determined by the least significant difference (LSD) test, and the significance was defined at P < 0.05. 3. Results and discussion 3.1. Proximate composition of grass carp muscle

2.7. TBA test Method was based on Gomes, Silva, Nascimento, and Fukuma (2003). The TBA (2-thiobarbituric acid) solution was prepared by weighing 0.3 g of TBA and transferring in a 100 ml beaker with 90 ml distilled water. The beaker was placed in a water bath (80 °C) until complete dissolution. The solution was then quantitatively transferred to a 100 ml volumetric flask and the volume completed with distilled water so as to achieve a 0.021 M TBA solution. Minced sample (50 g) was blended after the addition of 6 ml of ethanolic solution of butylated hydroxytoluene (BHT, 1 g/l) to prevent autoxidation. Aliquots of homogenized sample (10 g) were transferred to a flat-bottomed flask and one drop of silicone anti-foaming agent added plus 2.5 ml of 4 N HCl and 97.5 ml of distilled water. This sample was then distilled and the first 50 ml of distillate collected. Distillation was carried out in triplicate. Then

Proximate analysis showed that grass carp muscle contains 18.95 ± 0.53% total protein, 77.57 ± 0.37% moisture, 1.83 ± 0.12% total lipid, and 1.19 ± 0.09% ash. Grass carp muscle has a low lipid, intermediate protein, and high moisture content, similar to previous reports (Bakir, Melton, & Wilson, 1993). 3.2. Gel color Color measurements of grass carp gels were shown in Table 2. Gels with chitosan exhibited higher L (80.08– 83.68) than that of control (78.33) (P < 0.05). Significant differences of L values between gels containing high molecular weight chitosan (HC) or low molecular weight chitosan (LC) were not observed. However, L value increased significantly in gels when the mixture of high molecular weight chitosan and low molecular weight chitosan

L. Mao, T. Wu / Journal of Food Engineering 82 (2007) 128–134

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Table 2 Color parameters of grass carp gels with or without chitosan Chitosan

Chitosan levels (%)

Lightness (L)

Yellowness (b)

Whiteness (W)

Control

0

78.33 ± 0.52c

4.84 ± 0.11a

63.81 ± 0.69d

HC

0.5 1

80.19 ± 0.71b 80.08 ± 0.69b

4.56 ± 0.09b 4.51 ± 0.11b

66.51 ± 0.72c 66.54 ± 0.87c

LC

0.5 1

80.35 ± 0.54b 80.11 ± 0.34b

4.18 ± 0.10c 4.17 ± 0.13c

67.81 ± 0.78b 67.60 ± 0.63b

HC + LC

0.5 1

83.29 ± 0.81a 83.68 ± 0.65a

3.83 ± 0.13d 3.81 ± 0.10d

71.79 ± 0.90a 72.26 ± 0.75a

HC: 300 kDa chitosan (high molecular weight chitosan); LC: 10 kDa chitosan (low molecular weight chitosan); HC + LC: mixture of HC and LC (1:1, w/ w). Means in columns followed by different letters are statistically different using LSD (a = 0.05).

(HC + LC) was added (P < 0.05). The concentration of chitosan had no obvious effect on the lightness of gels. Yellowness (b) of gels decreased by the addition of chitosan, especially HC + LC (P < 0.05). The concentration of chitosan had no significant influence on yellowness of gels. The whiteness of grass carp gels varied from 63.81 to 72.26, and was improved by adding chitosan (P < 0.05). Difference in whiteness was also found within different molecular weights chitosan (P < 0.05). Gels containing HC + LC exhibited the highest whiteness. Generally, gels with high lightness, low yellowness and high whiteness are highly demanded by consumers (Hsu & Chiang, 2002). This study confirmed that addition of chitosan improved the gel color. Rearrangement and interaction of water, protein and polysaccharide molecules caused by the addition of chitosan could be the responsible for this improvement. The chitosan–chitosan interaction and protein–chitosan covalent crosslinking seems to modify the gel network, exhibiting a more lustrous and transparent appearance, and thus modifying the lightness of fish gels. 3.3. Textural properties Texture parameters including hardness, chewiness, springiness, cohesiveness, and adhesiveness were shown in Table 3. Addition of chitosan improved hardness and chewiness, with higher hardness and chewiness of HC or

HC + LC than LC (P < 0.05). Concentration of chitosan had a significant effect on the hardness of gels in all treatments (P < 0.05), when concentration increased from 0.5% to 1%. Grass carp gels had high springiness values. After the first compression, they almost recovered their original height, a typical characteristic of viscoelastic materials. At the concentration of 0.5%, chitosan showed no significant effect on the springiness value of fish gels when compared with that of control except HC. When the concentration of chitosan increased to 1%, springiness increased significantly (P < 0.05). Exhibition of cohesiveness was very close to that of springiness, only when the concentration of chitosan at 1%, cohesiveness of gels with chitosan was higher than that of gels without chitosan (P < 0.05), regardless of different type of chitosan. Adhesiveness values were significantly higher in gels containing LC or HC + LC than gels without chitosan (P < 0.05). There is no significant difference between the adhesiveness values of gels with different concentrations of chitosan. Influences of chitosan on texture of fish gels observed in this study were similar as previous reports in walleye pollock (Kataoka et al., 1998) and barred garfish (Benjakul et al., 2000; Benjakul et al., 2003). In the presence of chitosan, protein–polysaccharide conjugates would be formed between the reactive amino group of glucosamine and the glutaminyl residue of myofibrillar proteins. Bonds between chitosan and myofibrillar proteins could be associated with improving of texture properties in gels with the final structure

Table 3 Texture parameters of grass carp gels with or without chitosan Chitosan

Chitosan levels (%)

Hardness

Springiness

Cohesivene

Chewiness

Adhesiveness

Control

0

601 ± 19f

0.94 ± 0.02c

0.86 ± 0.01b

483 ± 20e

25.3 ± 5.2c

HC

0.5 1

857 ± 22b 898 ± 26a

0.96 ± 0.01b 0.99 ± 0.01a

0.86 ± 0.01b 0.91 ± 0.01a

700 ± 23b 804 ± 32a

33.3 ± 6.7d 34.7 ± 7.2d

LC

0.5 1

681 ± 23e 811 ± 21c

0.95 ± 0.01bc 0.98 ± 0.01a

0.86 ± 0.02b 0.92 ± 0.01a

559 ± 37d 725 ± 23b

17.4 ± 4.2b 18.1 ± 4.6b

HC + LC

0.5 1

761 ± 24d 887 ± 27a

0.95 ± 0.01bc 0.99 ± 0.01a

0.87 ± 0.02b 0.92 ± 0.01a

633 ± 29c 808 ± 32a

6.1 ± 1.3a 5.5 ± 1.1a

HC: 300 kDa chitosan (high molecular weight chitosan); LC: 10 kDa chitosan (low molecular weight chitosan); HC + LC: mixture of HC and LC (1:1, w/ w). Values in the same column followed by a different letter are significantly different (P < 0.05).

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formed by both covalent and non-covalent interactions. The effect would be also reportedly due to modification of the activity of the endogenous transglutaminase partly (Kataoka et al., 1998; Benjakul et al., 2000). 3.4. Expressible water Content of extracted water is inversely associated with the water holding capacity. Control product showed 13.56% expressible water (Table 4). Adding 0.5% chitosan did not decrease the amount of expressible water in gels. When 1% chitosan was added, a significantly decrease on the amount of expressible water was observed (P < 0.05), indicating that 1% chitosan improves the water holding capacity of restructured products. However, there were no differences between HC, LC and HC + LC. These results suggest that during the gelling of fish surimi containing chitosan, an increase of chitosan–water interactions might be induced. 3.5. TBA and peroxide values Lipid oxidation, corresponding to the oxidative deterioration of polyunsaturated fatty acids in fish muscle, leads to the production of off-flavors and off-odors, thereby shortening the shelf-life of food (Ramanathan & Das, 1992). The TBA value and peroxide value are both wellestablished methods for determining oxidation products (Kulas & Ackman, 2001). There were significant differences (P < 0.05) in the TBA values between the control and samples added with 1% chitosan, with contents of 0.184, 0.135, 0.095 and 0.114 mg MDA/kg in the control, 1%HC gels, 1%LC gels and 1%HC + LC gels, respectively (Fig. 1). After 15 days of storage, TBA values in the control, HC gels, LC gels and HC + LC gels increased to 1.181, 0.609, 0.352 and 0.424 mg MDA/kg, respectively (Fig. 1). TBA values of samples without chitosan were significantly higher than those with chitosan (P < 0.05). Peroxide values of samples with chitosan were significantly lower than that of control (P < 0.05). Changes of

1.4

TBA (mg MDA/kg)

132

Expressible water (%)

Control

0

13.56 ± 0.83b

HC

0.5 1

13.76 ± 0.73ab 6.58 ± 0.68c

LC

0.5 1

14.63 ± 0.88a 7.27 ± 0.92c

HC + LC

0.5 1

13.49 ± 0.81b 6.44 ± 0.90c

HC: 300 kDa chitosan (high molecular weight chitosan); LC: 10 kDa chitosan (low molecular weight chitosan); HC + LC: mixture of HC and LC (1:1, w/w). Means in columns followed by different letters are statistically different using LSD (a = 0.05).

15 days

0.2 0.0

Control

HC

LC

HC+LC

peroxide values were similar to TBA values, with contents of 1.01, 0.79, 0.61 and 0.65 meq/kg in the control, 1%HC, 1%LC and 1%HC + LC gels, respectively (Fig. 2). After 15 days of storage, TBA values in the control, HC gels, LC gels and HC + LC gels increased to 13.56, 8.98, 5.23 and 7.62 meq/kg, respectively (Fig. 2). As compared with the different molecular weight chitosans, inhibitory effect on lipid oxidation was as follows: 10 kDa chitosan > 300 kDa + 10 kDa chitosan > 300 kDa chitosan. This observation is indicative of the inhibitory effect on lipid oxidation in grass carp gels by chitosan, and this effect seems to have relations with its molecular weight. The results of our study are in agreement with those of Kamil et al. (2002) who found that among the different molecular weight chitosans, chitosan of lower molecular weight was more effective than the higher molecular weight chitosans in preventing lipid oxidation. Antioxidant activities of different molecular weights of chitosan in grass carp gels may be attributed to their metal-binding capacities. Several sources of protein-bound iron exist in fish tissues, the iron bound to these proteins may be released during gel formation and storage, thus activating oxygen and initiating lipid oxidation (St. Angelo, 1996). Chitosan may retard lipid oxidation by chelating ferrous ions present in the system, thus eliminating their peroxidant activity or their conversion to ferric ion.

Peroxide value (meq/kg)

Chitosan levels (%)

0 day

1.0 0.8 0.6 0.4

Fig. 1. Thiobarbituric acid (TBA) values of grass carp gels stored at 4 °C for 0 and 15 days. Gels added with 1% 300 kDa chitosan (HC), 1% 10 kDa chitosan (LC), 1% mixture of HC and LC chitosans (HC + LC) or without chitosan (control).

Table 4 Expressible water of grass carp gels with or without chitosan Chitosan

1.2

16 14 12 10 8 6 4 2 0

0 day

Control

HC

LC

15 days

HC+LC

Fig. 2. Peroxide values of grass carp gels stored at 4 °C for 0 and 15 days. Gels added with 1% 300 kDa chitosan (HC), 1% 10 kDa chitosan (LC), 1% mixture of HC and LC chitosans (HC + LC) or without chitosan (control).

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Furthermore, amino groups in chitosan may participate in the chelation of metal ions (Peng, Wang, & Tang, 1998; Xue, Yu, Hirat, Terao, & Lin, 1998). The varying antioxidant effect of chitosan may be attributed to the difference of molecular weight which determine the chelation of metal ions. In their charged state, the cationic amino groups of chitosan impart intramolecular electric repulsive forces, which increase the hydrodynamic volume by extended chain conformation (Anthonsen, Varum, & Smidsrod, 1993). Perhaps this phenomenon may be responsible for lesser chelation by high molecular weight chitosan. Furda (1990) has reported that the degree of polymerization of the glucosamine unit is a major factor determining the viscosity of chitosan. Thus the degree of deacetylation is another factor that may be involved in chelaton ability of chitosan. 4. Conclusions Chitosan could improve thermal gelling properties and prevent lipid oxidation of kamaboko gels from grass carp. Addition of chitosan improves gel color and texture with high whiteness and lightness, low yellowness, and high hardness and chewiness. When 1% chitosan is added, expressible water was significantly reduced. Chitosan of low molecular weight is more effective in preventing lipid oxidation than that of high molecular weight. Addition of 300 kDa chitosan or 10 kDa chitosan, at a level of 0.5–1%, would be considered as a promising approach in the preparation of grass carp gels for improving texture and stabilizing color and lipid to prolong shelf life. The present study should provide a possible application of chitosan as a food additive to surimi food systems. References Anthonsen, M. W., Varum, K. M., & Smidsrod, O. (1993). Solution properties of chitosans: conformation and chain stiffness of chitosans with different degrees of N-acetylation. Carbohydrate Research, 22, 193–201. AOAC (1995). Offcial methods of analysis of the association of the offcial analysis chemists (16th ed.). Arlington: Association of Offcial Analytical Chemists. Bakir, H. M., Melton, S. L., & Wilson, J. L. (1993). Fatty acid composition, lipids and sensory characteristics of white amur (Ctnepharyngodon idella) fed different diets. Journal of Food Science, 58(1), 90–95. Benjakul, S., Visessanguan, W., Phatchrat, S., & Tanaka, M. (2003). Chitosan affects transglutaminase-induced surimi gelation. Journal of Food Biochemistry, 27(1), 53–66. Benjakul, S., Visessanguan, W., Tanaka, M., Ishizaki, S., Suthidham, R., & Sungpech, O. (2000). Effect of chitin and chitosan on gelling properties of surimi from barred garfish (Hemiramphus far). Journal of the Science of Food and Agriculture, 81(1), 102–108. Borderı´as, A. J., Sa´nchez-Alonso, I., & Pe´rez-Mateos, M. (2005). New applications of fibres in foods: addition to fishery products. Trends in Food Science & Technology, 16, 458–465. Chin, K. B., Keeton, J. T., Longnecker, M. T., & Lamkey, J. W. (1998). Functional, textural and microstructural properties of low-fat bologna (model system) with a konjac blend. Journal of Food Science, 63(5), 801–807.

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