Notes
Effect of Incorporated Surimi on the Wheat Dough Rheological Properties and Noodle Quality
2014 Volume 20 Issue 6 Pages 1191-1197
Details
2014 Volume 20 Issue 6 Pages 1191-1197
The aim of this study was to investigate the effect of surimi on the rheological properties of dough and the quality of noodles in terms of cooking quality, appearance, texture and sensory properties. The results showed that dough development time, stability time, elastic modulus (G′) and viscous modulus (G″) increased with increasing content of surimi in the range of 30 – 50%. Noodles with surimi exhibited lower cooking loss and water absorption. Textural analysis showed that cooked noodles with surimi displayed higher firmness, springiness and chewiness than noodles without surimi. The sensory value of noodles significantly increased when 30% and 40% surimi was added. Surimi could be used for making noodle to improve the overall quality of noodle when used in proportions between 30% and 40%.
Noodles have become popular food for many countries in Asia since ancient time. Nowadays, their world consumption has increased, due to the ease of transportation, handling, cooking and preparation (Li et al., 2012a). Traditional noodles were prepared mainly from two basic ingredients: wheat flour and water (Inglett et al., 2005). In recent years, people pay more attention to taste and nutrition of noodles. In order to meet the needs of consumers, noodles that added vegetables, fruits and proteins have been developed (Marcoa and Rosell, 2008; Škrbić et al., 2009). Such added ingredients can provide different flavors, colors, additional nutrients and health benefits (Li et al., 2012b).
Proteins from various sources have been applied in order to increase nutritional value of cereal products. With that purpose, pea, soybean and whey proteins have been used in the rice flour, resulting in nutritional benefits and improved rheological properties of the rice dough (Marcoa and Rosell, 2008). In addition, the incorporation of gluten-soy protein blends could increase the protein content of cookies from 6% to 17.5% and reduce total carbohydrates (Singh and Mohamed, 2007). It was found that amaranth grain protein could improve the wheat dough strength and stability (Sanz-Penella et al., 2013). Rice protein isolate could provide necessary network for processing of rice products and decrease the cooking loss and water turbidity of rice noodle (Kim et al., 2014). It was also reported that noodle with 50% egg protein exhibited lower cooking loss and firmer texture (Khouryieh et al., 2006).
Surimi is obtained by washing fish mince with water resulting in a product containing mainly myofibrillar proteins (Pietrowski et al., 2011). Surimi protein can be an excellent source for making noodles with high nutritional properties, well-balanced amino acid and acceptable flavor (Auh et al., 2003). Surimi protein is rich in lysine, which is usually deficient in cereal grains. The deficiency of lysine leads to the poor utilization of protein and thus results in protein malnutrition. Study has shown that fish protein was added to wheat bread previously can significantly increase the lysine content of the bread (Ahlborn et al., 2005; Henselman et al., 1974). In addition, surimi contains unsaturated fatty acids, such as linoleic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which reported to be able to reduce the risk of coronary heart disease, decrease triglyceride, blood pressure and improve endothelial function (Juturu et al., 2008). Calcium, zinc, phosphorus and other minerals were also found in surimi (Auh et al., 2003). Therefore, surimi is suitable enrichment material for noodle and other cereal products.
By adding surimi, the rheological properties of dough and quality of noodle will be changed. However, limited information is available for the influence of surimi addition on the noodle quality. Therefore, the objective of this study was to investigate the effect of surimi on the rheological properties of wheat dough and the quality of noodle in terms of cooking quality, appearance, texture and sensory properties, and to determine acceptable surimi addition levels for producing high quality noodles.
Materials Strong wheat flour was obtained from Auchan Supermarket (Wuxi, Jiangsu). The moisture, crude protein, lipid and ash content of the wheat flour were 13.81, 14.65, 0.36 and 0.63%, respectively. Moisture, protein, lipid and ash were determined by AACC approved method 44 − 19, 46-10, 30 − 10, 08 − 01 (AACC, 2000). Frozen silver carp surimi was obtained from Jing Li Aquatic Food Co., Ltd. (Honghu, Hubei). The moisture, protein, lipid and ash content of the surimi were found to be 78.66, 18.89, 1.04 and 0.91%, respectively. Frozen surimi also contained 4% sorbitol and 0.25% polyphosphate. The frozen surimi was thawed at 4°C for 12 h, weighed, added 2% salt (w/w, surimi basis), homogenized by a homogenizer (Jiu Yang, JYS-A900, China) for 1 min. Surimi was placed in a polyethylene bag for use.
Farinograph properties The dough's farinograph properties were investigated by a farinograph (Brabender, Farincgreph-E, Germany) according to the standard method 54 − 10 of AACC (2000). Wheat flour with different proportions of surimi of 0, 10, 20, 30, 40 and 50% (w/w, flour basis) was formulated before analyzing (Dough was hard to form when surimi content exceeds 50%). The water absorption (WA), dough development time (DDT), stability time (ST) and degree of softening (DS) were recorded manually.
Dough oscillatory measurements Surimi was added to the flour at the levels of 0, 10, 20, 30, 40 and 50% (w/w, flour basis). Farinograph dough kneading pot was used to mix flour and surimi until dough consistency is up to 500 FU. The dough was packaged using a fresh-keeping film and allowed to rest for 45 min. Dynamic rheological measurements of the dough were determined on the AR1000 rheometer (TA Instruments, New Castle, DE). The measuring system was consisted of parallel plate geometry (20 mm diameter, 2 mm gap). Measurements were performed at 25°C. Frequency sweep tests were performed from 0.1 to 10.0 Hz to determine the storage modulus (G′) and loss modulus (G″) as a function of frequency.
Preparation of noodles Noodles were prepared using the method previously described by Wang et al. (2012) with some modifications. Wheat flour and different proportions of surimi of 0, 10, 20, 30, 40 and 50% (w/w, flour basis) were mixed with 34% water (w/w, flour basis) to make dough. Dough was allowed to rest 45 min and shaped into a thin of 3 mm with a pressing machine (Shu Le, QM005, China). Dough was folded and sheeted three times. The dough sheet was put through the sheeting rolls three times. Noodles obtained from the cutting rolls of the noodle machine were dried at 40°C for 10 h. The characteristics of final dried noodles containing different proportions of surimi of 0, 10, 20, 30, 40 and 50% were (g/100 g): moisture 9.81, 9.85, 9.92, 9.79, 9.88 and 9.90; protein 13.84, 14.66, 16.05, 16.70, 18.05 and 19.21; lipid 0.38, 0.54, 0.71, 0.89, 0.98 and 1.12; and ash 0.47, 0.61, 0.70, 0.82, 0.88 and 0.93, respectively. The noodle samples were packed in plastic bags, stored at 25°C and rested for two weeks before analysis.
Pasting properties of noodles The pasting properties of noodle were investigated with a rapid visco-analyzer (RVA-RECHMASTER, Newport Scientific, Australia). The method was referred to the study of Ribotta (Ribotta and Rosell, 2010). A 12% noodle-water suspension (28 g total weight) was prepared and subjected to a heating-cooling cycle. Data gathering and analysis were performed using thermocline for Windows software, provided by the instrument manufacturer. Pasting temperature (PT), peak viscosity (PV), holding viscosity (HV), final viscosity (FV), breakdown (BD) and setback (SB) were obtained from the viscograms.
Cooking quality of noodles The noodle's optimum cooking time was determined as described by Wang et al. (2012) with a slight modification. Noodles (10 g) in 22 cm lengths were added to 500 mL of rapidly boiling distilled water in a beaker. Optimum cooking time corresponded to the disappearance of the opaque core of noodle when the noodle was squeezed between two glass plates. Cooking loss and water absorption of noodle were measured and calculated as described by Khouryieh et al. (2006).
Texture of noodles Textural properties were measured using a TA-XT2 Texture Analyzer (SMS, London, UK). 20 g noodles were cooked in 500 mL of boiling distilled water for optimum cooking time, dried with filter paper. Samples were tested 10 min after cooking. Measurements were carried out at room temperature (25°C). Calibration settings used were the 5 kg load cell with a return trigger path at 15 mm. The measurement mode settings for compression (pre-test, test and post-test) were set to a speed of 2.0 mm/s, 1.0 mm/s and 1.0 mm/s; strain was at 70%; trigger type at auto-10 g and a 35 mm cylinder probe was used (Stable Micro Systems, 2000). Hardness, springiness and chewiness automatically calculated by the program.
Color measurement A Chroma meter (Minolta CR-100) equipped with D65 illuminant using the CIE 1976 L*, a* and b* color scale, was used to measure the color of noodles. L* measures brightness (0 – 100), a* represents the red-green coordinates (− is green with + indicating redness) while b* measures the blue-yellow coordinates (_ is blue with + indicating yellowness) of a product. A sample of noodle was ground using a mortar and pestle and packed into a small resealable plastic bag. This was then folded in half and the color of the sample was measured through the transparent bag.
Sensory evaluation Nine trained panelists including five female panels and four male panels from the Food Science Inst. at Jiang Nan Univ. participated in the sensory analysis. The average age of panelists was 24. The trained descriptive panel spent 4 h training to become familiar with the definitions and references. The panelists evaluated noodle color, roughness, stickiness, firmness, flavor and overall quality. Each attribute was evaluated on a 9-point scale as follows: color (1 = light, 9 = dark); roughness (1 = smooth, 9 = rough); stickiness (1 = not sticky, 9 = sticky); firmness (1 = soft, 9 = firm); flavor (1 = none, 9 = strong); overall quality (1 = lowest, 9 = highest).
Statistical analysis SPSS Statistics 17.0 was used for analysis. Measurements of the penetration test were analyzed by one-way analysis of variance at a significance level of 0.05. Differences in mean values were assessed with Duncan multiple comparison procedure.
Farinograph characteristics The effects of surimi with different concentrations on the farinograph properties of dough samples are presented in Table 1. The percent of water absorption (WA) significantly (p < 0.05) decreased with the addition of surimi increased from 10% to 50%. Surimi contained water, which could be used for dough development. Thus less water was needed for noodle formation. The dough development time (DDT) associated with dough elasticity. The stability time (ST) was an indication of the strength of dough. In this study, DDT and ST significantly (p < 0.05) increased as the addition of surimi increased from 30% to 50%. The higher DDT and ST values suggested stronger dough (Li et al., 2012b). The increase of DDT and ST indicated that surimi addition produced more stable dough. A similar trend was reported that amaranth proteins modified the stability-related mixing parameters (DDT and ST) of dough (Oszvald et al., 2009). Degree of softening (DS), also called mixing tolerance index, was applied to determine the amount that dough would soften over a period of mixing. Added surimi at 10% and 20% levels gave higher DS values compare with control sample. However, DS decreased significantly (p < 0.05) with increasing the surimi level from 30% to 50%. DS decrease showed dough ability to resist mixing enhanced. A network-like structure could be created with surimi protein and gluten, which could strengthen the dough structure during mixing. Oszvald et al., (2009) found that amaranth albumin proteins are capable of interacting with gluten proteins in wheat flour, improving dough strength and stability. Similar trend was also observed in the study of the blended wheat flour and soy flour (Singh and Mohamed, 2007).
| Surimi (%) | Farinographic characteristics1 | |||
|---|---|---|---|---|
| WA (%) | DDT (min) | ST (min) | DS (FU) | |
| 0 | 63.8f±0.8 | 2.8c±0.0 | 4.7c±0.1 | 61.3d±0.6 |
| 10 | 55.6e±0.5 | 2.1a±0.1 | 3.0a±0.1 | 77.3f±0.6 |
| 20 | 51.0d±0.2 | 2.3b±0.1 | 3.7b±0.0 | 67.0e±1.0 |
| 30 | 48.4c±0.5 | 3.1d±0.0 | 6.1d±0.1 | 51.5c±1.2 |
| 40 | 43.7b±0.3 | 3.8e±0.1 | 7.3e±0.0 | 45.3b±1.5 |
| 50 | 39.5a±0.3 | 4.4f±0.0 | 7.8f±0.2 | 42.6a±1.1 |
a–f Means different letters within the same column differed significantly (p < 0.05) (n = 3).
Dough oscillatory measurements The viscoelastic properties of dough containing different levels of surimi were studied by dynamic oscillatory measurements. Results are shown in Fig. 1. The mechanical spectra of all the samples showed elastic modulus (G′) values higher than viscous modulus (G″) at all the frequency range tested, which suggest a viscoelastic solid behavior of the dough (Kim et al., 2014).
Elastic (G′) and viscous (G″) moduli with the frequency for dough with different proportions of surimi.
G′: ○ - 0%, ▽ - 10%, ▷ - 20%, ◇ - 30%, △ - 40%, □ - 50%; G″: ● - 0%, ▼ - 10%, ▶ - 20%, ◆ - 30%, ▲ - 40%, ■ - 50%.
The presence of surimi significantly (p < 0.05) changed the viscoelastic properties of dough. Compared with the control group, G′ decreased as the addition of surimi increased from 10% to 20% but increased as the addition of surimi increased from 30% to 50%. A similar trend was observed on the G″. Different proportions of surimi had different effects on the viscous and elastic properties of dough. A probable explanation for the difference could be that with mixing a network is formed between wheat protein and surimi protein. This might increase the G′ and G″ as a result of bringing starch granules into the protein network and restriction of water movement within the network. The increase in the protein concentration allowed the construction of a stronger network and limited water migration to the protein at the expense of the starch (Kim et al al., 2014). Surimi in the proportions from 10% to 20% weakened the binding structure of dough and decreased the G′ and G″, but more surimi can form elastical gel network structure, which was strong enough to counteract the weakening effect of dough structure. Marcoa and Rosell (2008) also reported that pea and soybean proteins could significantly (p < 0.05) increased G′ and G″ of dough.
Pasting properties of noodles Noodles' pasting parameters are shown in Table 2. The results indicated that PT increased with the surimi proportions increased from 10% to 50%. A similar result was reported by Goel et al. (1999), who studied the effect of casein on corn starch gelatinization. Mixtures of corn starch and casein showed an increase of PT relative to corn starch. Another previous study reported the similar viscosity pattern when added soy protein isolate into wheat flour (Ziegler and Foegeding, 1990). PV was considered to be an indicator of water-binding capacity and significantly (p < 0.05) decreased with the addition of surimi (10 50%). A decrease in the viscosity was also observed when prolamin proteins were added to rice flour (Baxter et al., 2004). The reduction was likely due to the dilution effect on the starch concentration (Li et al., 2012a; Tan and Corke, 2002). Surimi also promoted a significant (p < 0.05) decrease of the FV by 30% when compared to the value of control group. This is in agreement with the study of Marcoa and Rosell (2008), who reported that the FV decreased with pea, soybean and whey proteins addition. The BD, related to the ability of starches to withstand heating at high temperature and shear stress, showed a significant (p < 0.05) decrease with the increase of surimi from 10% to 50%. Marcoa and Rosell (2008) also observed the presence of the egg albumen and whey protein isolates significantly (p < 0.05) decreased the BD value. Setback was related to the retrogradation of the amylose chains and reduced when surimi was added. Overall, a decrease in the viscosity profile was likely due to the dilution of starch component by protein substitution (Kim et al., 2014).
| Surimi (%) | Parameters of pasting behaviors1 | |||||
|---|---|---|---|---|---|---|
| PT (°C) | PV (cP) | HV (cP) | FV (cP) | BD (cP) | SB (cP) | |
| 0 | 74.9a±0.0 | 2294f±16 | 1526f±9 | 2601f±9 | 781e±3 | 1076f±8 |
| 10 | 75.7b±0.0 | 2170e±18 | 1416e±8 | 2434e±7 | 767d±3 | 1039e±7 |
| 20 | 76.6c±0.1 | 2118d±4 | 1365d±7 | 2338d±19 | 755d±2 | 995d±6 |
| 30 | 77.5d±0.1 | 1960c±11 | 1290c±7 | 2207c±6 | 674c±5 | 914c±15 |
| 40 | 78.3e±0.1 | 1903b±8 | 1274b±5 | 2115b±10 | 634b±6 | 849b±19 |
| 50 | 78.3e±0.1 | 1827a±17 | 1165a±11 | 1998a±11 | 611a±15 | 767a±18 |
a–f Means with different letters within the same column differed significantly (p < 0.05) (n = 3).
Texture of noodles The texture profiles of noodles were affected by the composition of surimi as shown in Fig. 2. Texture of cooked noodle is considered as the most critical characteristic in evaluating the quality of noodles and determining consumer acceptance of the product (Bhattacharya et al., 1999; Dexter et al., 1985). Hardness significantly (p < 0.05) increased as the proportions of surimi increased from 10% to 50% (Fig. 2A). During cooking process, surimi was heated and formed gel network structure, gave the noodle solid like texture and increased the hardness of noodle. The result was agree with the findings of Dalbon et al. (1996), who reported that egg proteins could form protein network through intermolecular forces and increased the hardness of cooked noodles. Hardness of noodle also related to protein levels. Malcolmson et al. (1993) reported that the hardness of spaghetti increased with increasing semolina protein level. Springiness (Fig. 2B) and chewiness (Fig. 2C) of noodle showed a significant (p < 0.05) increase with the surimi increased from 10% to 50%. Baik reported that starch characteristics and protein content were highly correlated with noodle textural properties. Stronger protein network generally related to higher hardness and springiness of noodle (Baik et al., 1993). With the addition of surimi, starch adhered to the protein network. Flexible gel structure was formed between starch and protein during heating process, which improve noodle springiness and chewiness.
Hardness (A), Springiness (B) and Chewiness (C) of noodles with different proportions of surimi.
Cooking quality of noodles There was a slight variation in the optimum cooking time among the noodle samples, as shown by the values of 4.2 – 6.5 min with the proportions of surimi increased from 0% to 50% (Table is not shown). Fig. 3 showed the cooking loss and water absorption of noodles. The results indicated that the cooking loss decreased from 13.14% to 12.06% as the surimi proportion increased from 10% to 50% (Fig. 3A). The cooking loss is commonly used as an indicator of cooked spaghetti quality. Low amounts of cooking loss indicate high pasta cooking quality (Del Nobile et al., 2005). Cooking loss of pasta is attributed to the interactions of protein and starch in the presence of water (Güler et al., 2002). The decrease of cooking loss with the addition of surimi may be due to the formation of gel network structure between starch and protein during heating process, which prevents leaching of starch. Water absorption of noodle declined from 199% to 155% with the addition of surimi increased from 0% to 50% (Fig. 3B). It was reported that the cooking quality of noodle is influenced primarily by the properties of the protein and starch (Wood et al., 2001). Starch granules were surrounded by surimi protein and water absorption capacity of starch decreased with the addition of surimi. Low water absorption related with low stickiness, good surface conditions and good quality of noodle (Abecassis et al., 1989; Khouryieh et al., 2006). Therefore, increasing the amounts of surimi improve the noodle cooking quality.
Cooking loss (A) and water absorption (B) of noodles with different proportions of surimi.
Color measurements Color is one of the most important esthetic features in the quality of noodles. The color values of noodle are shown in Table 3. By increasing the surimi level from 0% to 50%, the color measurement of L* values increased. The a* values decreased and the sample appeared to have a fairly uniform tinge of green color. The b* values of noodles increased and turned to a yellow color. The total color difference (ΔE) increased with the increase of the surimi addition in the noodle. The result showed that the addition of surimi have a positive effect on noodle colors.
| Surimi (%) | Color parameters | |||
|---|---|---|---|---|
| L* | a* | b* | ΔE | |
| 0 | 89.60a±0.01 | 0.75c±0.03 | 8.19a±0.16 | 89.97a±0.02 |
| 10 | 89.75b±0.18 | 0.72c±0.03 | 9.20b±0.07 | 90.22b±0.18 |
| 20 | 90.17c±0.02 | 0.67b±0.04 | 10.08c±0.06 | 90.74c±0.02 |
| 30 | 90.14c±0.07 | 0.68b±0.01 | 10.42d±0.15 | 90.75c±0.06 |
| 40 | 90.37d±0.06 | 0.53a±0.01 | 10.57e±0.02 | 90.99d±0.05 |
| 50 | 90.60e±0.01 | 0.53a±0.01 | 10.76f±0.02 | 91.24e±0.01 |
a–f Means different letters within the same column differed significantly (p < 0.05) (n = 6).
Sensory evaluation The sensory evaluation was the nearest to a consumer's estimation and still remained the most reliable test because it allowed the overall characteristics of cooked noodles to be evaluated. The sensory scores of noodles are shown in Table 4.
| Surimi (%) | Sensory attribute1 | |||||
|---|---|---|---|---|---|---|
| Color | Roughness | Stickiness | Firmness | Flavor | Overall quality | |
| 0 | 3.7f | 2.2a | 5.3e | 4.5a | 5.4a | 6.6a |
| 10 | 3.2e | 2.8b | 4.4d | 5.3b | 6.6b | 7.1b |
| 20 | 3.0de | 3.1bc | 4.0c | 5.9bc | 7.2c | 7.3c |
| 30 | 2.4c | 3.3cd | 3.5b | 6.2c | 8.1d | 8.0d |
| 40 | 2.1b | 3.2bcd | 3.2a | 6.9d | 8.5de | 8.5e |
| 50 | 2.0ab | 4.6e | 3.4a | 7.8e | 8.8f | 7.0b |
a–f Means different letters within the same column differed significantly (p < 0.05) (n = 9).
Noodles with surimi exhibited better color values than control sample, which in accordance with instrumental color analysis of cooked noodles. Stickiness was affected by the amount of unabsorbed water associated with drained cooked pasta and was related to the amount of amylase leached from the gelatinized starch granules (Del Nobile et al., 2005). Noodles containing more surimi had significantly (p < 0.05) lower stickiness scores. Surimi addition caused slight increases in chewing properties of noodle. The roughness and flavor of cooked noodles were significantly (p < 0.05) affected by the addition amount of surimi. The flavor scores and roughness scores tended to be marginally higher for noodles containing surimi. Overall quality scores of noodle increased when surimi addition amount increased from 10% to 40%. Noodle was too hard to eat and sensory score decreased when surimi proportion more than 40%. The noodle sample with a surimi level of 40% gave the best sensory properties among the noodle samples produced in the present study.
Surimi could be used as raw materials for making noodles, increasing the product's nutritional value and providing an increase in protein levels. The combination of surimi with the wheat flour creates dough with a higher strength and elastic texture, allowing noodles to obtain a stronger structure. An improvement in appearance and cooking quality of noodle were also observed by adding surimi. Therefore, it is possible to utilize surimi in noodle production to improve its overall quality. In order to maintain both the nutritional benefit of surimi and noodle quality, the proportions of surimi should be limited in the range of 30% – 40%.
Acknowledgements This research was financially supported by the earmarked fund for China Agriculture Research System (CARS-46).
