• Korean journal of food and cookery science
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• v.32 no.3
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• pp.253-260
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• 2016

Purpose: To develop fat-free dressing containing a resistant starch (RS) as a dietary fiber, the viscosity and stability of various type RSes prepared from wheat, maize, potato, rice, waxy rice, and amaranth starches were investigated by using Brookfield viscometer. The shape of RS granule in the dressing during storage was also observed. Methods: The viscosity of fat free dressing with different retrograded RS3 (RS3V) prepared from waxy rice starch with 0.1% lemon vinegar and ascorbate mixed solution had higher RS3 that was maintained constant during storage. Annealing and heating prior to cross-linking, and heating after cross-linking increased RS level of RS4 type starches. Results: The viscosities and stabilities of dressings with RS were different depending on starch sources and RS preparation conditions. The heated RS4 (HRS4) increased in viscosity and stability with RS4 addition. Especially the fat-free dressings with HRS4 prepared from rice and waxy rice starches maintained stability regardless of separation after one month storage with only 7% separation after 6 month storages. The shape of RS4 granule in acidic medium of dressing did not change until 6 months. Conclusion: In this study, RS4 made by the rice and waxy rice starches showed high viscosity and maintained stability of the fat-free dressings during storage.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.366-371
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• 2011

Viscosity is critically important for bulgogi sauce. However, exposure to irradiation may decrease the rheological properties of bulgogi sauce. This study was conducted to compare the effects of gamma irradiation (0-9 kGy) on viscosity, molecular weight, pH, reducing end level, and water solubility of xanthan gum, guar gum, and locust bean gum as thickening agents/stabilizers in bulgogi sauce. The physicochemical properties of all samples changed (p<0.05) from 3965 to 0 cP (viscosity), from 6048 to 28 kDa (molecular weight), from 5.79 to 4.62 (pH), from 0.13 mg/mL to 1.72 mg/mL (reducing end level), and from 6% to 87% (water solubility) following gamma irradiation. Viscosity after irradiation was most stable (p<0.05) in xanthan gum (from 1249 to 92 cP) compared with guar gum (from 3965 to 0 cP) and locust bean gum (from 1631 to 0 cP). The sensory properties (texture and taste) of bulgogi sauce prepared with xanthan gum (1%, w/w) were highly maintained (about 7.0-5.0) after high-dose irradiation of up to 40 kGy. These results indicate that xanthan gum can be effectively used as a thickening agent/stabilizer in bulgogi sauce, which had low viscosity after irradiation.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.855-860
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• 2009

Physicochemical properties of starches isolated from 3 new potato cultivars developed by Potato Valley Ltd. were investigated and compared to those of starch isolated from 'Superior' being distributed prominently in Korea. Significant differences were observed in physicochemical properties such as granule size, amylose content, phosphorus content, water binding capacity, swelling power, solubility, and in vitro digestibility of starches from different potato cultivars. Thermal properties were evaluated using differential scanning calorimetry (DSC), and onset gelatinization temperatire ($T_o$), peak temperature ($T_p$), and enthalpies of gelatinization (${\triangle}H$) of different potato cultivars ranged as $58.0{\pm}0.3-61.7{\pm}0.4^{\circ}C,\;63.7{\pm}0.2-$ $66.5{\pm}0.0^{\circ}C$, and $15.6{\pm}0.5-17.0{\pm}0.3$ J/g, respectively. Pasting properties were evaluated using a rapid visco analyzer (RVA), and pasting temperature, peak viscosity, and final viscosity of different potato cultivars ranged as $65.0{\pm}0.1-68.9{\pm}0.1^{\circ}C$, $8,163.7{\pm}196.3-9,035.7{\pm}6.4$ cp, and $4,397.7{\pm}166.7-7,025.0{\pm}271.3$ cp, respectively. Especially, 'Gogu valley' starch showed the highest values in the amylose and phosphorus content among tested potato cultivars and higher water binding capacity, swelling power, and solubility than those of other tested starches. And it also showed high pasting temperature, peak viscosity, trough viscosity, and final viscosity as compared to other tested starches.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.593-600
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• 2008

The principal objective of this study was to evaluate the quality characteristics of dried noodles when different concentrations of Lotus root powder were added to the wheat flour. The cooking quality, mechanical textural properties, and viscosity were measured, and a sensory evaluation was conducted with the prepared noodles. The gelatinization points of the composite Lotus root powder-wheat flours were shown to have increased and the viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity values of those samples were reduced, as the Lotus root powder content was increased as measured via amylography. As increasing amounts of Lotus root powder were added, the L and b values were reduced, and the color values, weight, and volume of the cooked noodles increased, as did the turbidity of the soup. With regard to the textural characteristics, the Lotus root powder additive increased hardness and reduced adhesiveness, cohesiveness, and springiness. Overall, the noodles prepared with 15% Lotus root powder were preferred more than the other noodles, according to the results of our sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.932-938
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• 1997

Changes in viscosity and dynamic theological properties of Job's-tears were measured by Bohlin dynamic tester as a function of moisture, and measurement was performed within a linear viscoelastic range. The result of the shear stress vs shear rate of Job's-tears at different moisture contents $(50{\sim}75%)$ was applied to mathematical models and Herschel-Bulkley model showed the highest correlation coefficient. Lower moisture content (55%) produced higher yield stress and consistency index, but lower flow behavior index, whereas higher moisture content showed reverse effects. Job's-tears with $50{\sim}70%$ moisture contents showed a higher storage modulus (G') than loss modulus (G') at all frequencies, showing a higher concentrated polymer characteristics. However, higher moisture content (>75%) showed crossover point between G' and G', and frequency dependency. As the moisture content was increased, the amount of viscoelastic properties such as G', G', complex viscosity decreased during heating, and initial temperature and miximum value of viscoelastic properties shifted to higher temperatures, representing the moisture-dependence of Job's-tears upon theological properties.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.378-384
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• 2006

Intrinsic viscosity of starch irradiated with Co-60 (0.25-9.1 kGy) significantly decreased, and swelling power and solubility measured at $80^{\circ}C$ linearly increased with increasing irradiated dose. Radiation treatment up to 1 kGy increased amylose content of starch. Water-binding capacity increased rapidly up to 3 kGy. Peak viscosity of irradiated starches by Rapid visco Analyser and Visco/amylo/Graph indicated that the decrease in peak viscosity was dose-dependent. Gamma irradiation showed no effect on endothermic temperatures of irradiated starches, but decreased endothermic enthalpy with increasing dose level. Viscosity of starch autoclaved at $120^{\circ}C$ and air-dried significantly decreased with increasing irradiation dose. Resistant starch content slightly decreased upon irradiation.

• The Korean Journal of Food And Nutrition
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• v.7 no.4
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• pp.353-360
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• 1994

Effect of pH, calcium, sucrose, heating and mixing ratio of soy and cow milk was studied on the viscosity and the sensory characteristics of cow-soy milk. The viscosity of soymilk was significantly affected by pH with showing maximum at 6.0 and the pH effect was decreased as the ratio of cow talk increased. A addition of sucrose or calcium affected little on the viscosity and a negative linear relationship was found be tween viscosity and an increase in cow milk ratio. Sensory characteristics of grassy and beany odor and taste of soymilk were rapidly decreased and nutty flavor and total acceptability were increased during initial 30 min of boiling. A further increase in boiling affected little on tastes and odors of soymilk. The beany odor and taste linearly decreased and milk flavor Increased as the ratio of cow milk increased. The total acceptability of 50 : 50 was found to be maximum for cow and soy mixed milks.

• Journal of the Korean Society of Food Culture
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• v.19 no.6
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• pp.667-677
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• 2004

This study was conducted to examine contents of mineral, viscosity in the Demi-glace with added quantity of Omija extracts. Firstly, The level of mineral content in order was K, Na, P, Ca, Mg, Fe, Zn, Mn, B. The more Omija extracts, Ca, Mg, Fe, Zn, Mn, B was increased, but K, Na, P was decreased. Secondly, Viscosity of control was 538.13cP at rpm 100, and the sauce added with Omija extracts was $464.80{\sim}578.00cP$. Regardless of Omija quantity there was Psedoplastic characteristic which showed apparent viscosity was decreased even though shear rate was increased. Thirdly, Sensory characteristics of Demi-glace sauces based on preference of 5 tastes, It was founded that 2% added Omija was the best, and 1%, 0%, 3%, 5% added Omija was next in order. Finally, Sensory intensities of Demi-glace sauces based on gender and occupation of the 5 tastes : As the sourness, bitterness, hotness, salines taste of all over was Omija added quantity was many more, appeared strong intensity, it was sensory intensities of 5% Omija added sauce was the highest. But sensory intensities of sweetness, Male showed 2% Omija added sauce, Female student and cook showed control was the highest.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1082-1086
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• 1999

Dried vegetables, white ginseng and spices, which were exposed to gamma and electron beam irradiation, were used in a detection study by measuring their starch content and viscosity change. The samples tested showed different levels of starch content(15.64~60.86%), which was not directly proportional to the viscosity of the samples. The correlation coefficients between irradiation dose and viscosity change were lower in the samples, such as cabbage, carrot, clean vegetable(chunggyungchae), garlic, mushroom, green onion, and red pepper, while some higher coefficients were found in ginger(R2=0.9271), white ginseng (R2=0.6223) and onion (R2=0.7909). Thus, dried ginger and white ginseng were selected to be used for a detection of irradiated samples using specific parameters(threshold values). Specific parameter for the nonirradiated ginger and ginseng were 13.31 and 13.93, respectively. On the other hand, gamma and electron beam irradiated samples at 2.5 kGy, the lowest dose for a commercial purpose, showed decreased values, 11.92 and 11.15 in ginger, and moreover 4.40 and 5.10 in ginseng. It is expected that a proportional decrease in a specific parameter with the absorbed doses will be a potentially useful index for detecting whether starchy foods have been irradiated or not.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.427-432
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• 2007

The texture and descriptive sensory characteristics of a Korean rice cake(Karedduk) with added emulsifier were investigated after 2 and 24 hrs of storage at $5^{\circ}C$. The emulsifier, SP, was added at 0, 0.1, 0.5 and 1% levels to the dry rice flour. In the amylogram, the peak viscosity(P), hot paste viscosity(H) and cold paste viscosity(C) of the rice flour with added emulsifier were higher than those of the control. The texture property analysis by a Texture Analyzer revealed that the springiness, cohesiveness and adhesiveness of the Korean rice cake(Karedduk) with added emulsifier were similar to those of the control, while chewiness, gumminess and hardness were lower compared to the control. Also, the hardness by sensory characteristics was significantly different as compared to the control. Lastly, adding emulsifier to the Korean rice cake(Karedduk) was effective at retarding retrogradation.