• Preventive Nutrition and Food Science
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• v.5 no.1
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• pp.20-24
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• 2000

A study was carried out to establish the detection method of irradiated corn, potato, and sweet potato starches. The samples were packed in polyethylene bags and irradiated with 1, 3, 5, 7, 10, and 15 kGy using a Co-60 irradiator. The maximum viscosity of irradiated and unirradiated corn, potato, and sweet potato starches reduced by increase of irradiation dose levels and showed significant differences which clearly showed the effect of irradia-tion dose levels (p<0.05). Regression expressions and coefficients (p<0.000) or corn, potato, and sweet potato starches were y=-38.538x+718.23(r2=0.9761), y=669.97e-0.1372x (r2=0.9820) and y=-42.544x+730.26(r2=0.9939), respectively. Nor-malized parameter A,B and C values showed a dose dependent relationship and were a better parameter for detecting the irradiated starches than that of the maximum viscosity itself.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.753-757
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• 1993

Pasting properties of the two commercial products of air-dried sediment of acorn were studied with viscoamylograph. The concentrations used were 7.0~9.5% and heating temperatures were 86.5$^{\circ}C$, 89.5$^{\circ}C$ and 92.5$^{\circ}C$. The viscosity increased as the heating temperature increased at a fixed concentration, but sample A at 8.5% concentration and sample B at 9.5% concentration maintained the constant peak viscosity regardless the heating temperatures. Samples heated to 92.5$^{\circ}C$ showed breakdown at all concentrations. The 15-min height and cold viscosity were negatively correlated with the heating temperature at a constant concentration. There was a 1% difference in concentration to give the same indices of amylogram between two samples.

• Journal of the Korean Society of Food Culture
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• v.24 no.4
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• pp.419-425
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• 2009

This study examined the effects of added amounts of shrimp powder on the physical and sensory properties of Jook for elderly foodservice operation. According to the amylograph data, the composite shrimp flour-wheat flour samples increased the gelatinization temperature, with increasing shrimp-flour content; moreover, initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity were reduced. As the level of shrimp powder in samples increased, L-values decreased, and a-values and b-values increased. In addition, the Jook had higher viscosity and lower spreadability values as the amount of shrimp powder increased. Sensory characteristics, such as nutty taste, color, viscosity, and overall preference increased significantly with the addition of shrimp powder. In conclusion, to enhance the quality of Jook, a 3% addition of shrimp powder would be the most beneficial.

• Korean Journal of Human Ecology
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• v.1 no.1
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• pp.79-83
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• 1992

Cowpea starch which is the main ingredient of Mook(Korean starch gel) was isolated from cowpea and characterized by physico-chemical methods. Gelatinization properties were investigated by using Brabender amylograph. Starch granules were oval-shape and their size range was $5\;-\;25{\mu}m$. Crystalline type observed by X-ray deffraction was C-type. Apparent amylose content was 20.7%, Amylose and amylopectin fractionated from cowpea starch appeared to have vlue value of 0.55 and 0.089, and ${\beta}-amylolysis$ limit of 79.1 and 71.9%, respectively. Brabender amylograph data showed that initial gelatinization temperature of cowpea starch was $75^{\circ}C$. Also, hot and cooled paste viscosity of 8% starch paste were higher than that of 6% paste by more than twice, breakcown value of two different concentration were almost same. However, in the gelation stage, consistancy and setback of 8% starch paste appeared more than 5 times of those of 6% paste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.817-823
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• 1996

The rheological prouerties of dough were evaluated the dough added whole wheat flour during breadmaking. From the farinogram, water absorption of the dough was decreased as the amount of coarse whole wheat flour was increased. While water absorption of the dough was increased as the amount of fine whole wheat flour was increased. Arrival time and development time of the dough with coarse whole wheat flour were longer than those of fine whole wheat flour. As the amount of whole wheat flour was increased, the weakness was increased. Weakness of coarse whole wheat flour was higher than that of fine whole wheat flour. From the extensograph, extension and resistance to extension were decreased with increasing the amount of whole wheat flour. Resistance to extension of coarse whole wheat flour was higher than that of fine whole wheat flour. From the amylograph, as the amount of whole wheat flour increased, maximum viscosity was decreased gradually. Though the amount of coarse whole wheat flour and fine whole wheat flour was increased up to 30% and 50%, respectively, external characteristics of bread was remained in normal. As the amount of whole wheat flour was increased, the value of whiteness was decreased.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1421-1426
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• 1999

Sixteen domestic barley varieties and subsequently produced malts were evaluated for quality characteristics. Diastatic power(DP), complementary actions of amylases in malt, had a wide $variation(139{\sim}220^{\circ}L)$ among the barley varieties. Some 6-row barley varieties demonstrated significantly high DP values. ${\beta}-\;and\;{\alpha}-amylase$ activities in malts were also significantly influenced by barley varieties. Diastatic power was highly correlated with ${\beta}-amylase$ activity, indicating that the ${\beta}-amylase$ activity was a predominant factor determining saccharifying action in malt. Amylograph was used to indirectly estimate starch-degrading enzymatic activity, and the reduction in amylograph viscosity was associated with ${\alpha}-amylase$ activity. Barley quality factors in relation to enzymatic activity of malt were analyzed, and the barley variety with lower kernel weight and less plumper kernels tended to produce higher starch-degrading enzyme activity. Potential diastatic power, an estimate of bound ${\beta}-amylase$ in raw barley, was associated with diastatic power in the final malt. Potential diastatic power turned out to be an important factor for predicting good malting barley.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1819-1825
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• 2015

This study was carried out to investigate the effect of hydrocolloids [hydroxypropylmethyl cellulose (HPMC), xanthan gum (XG), guar gum (GG), and glucomannan (GM)] on the physicochemical properties of bread flour dough containing rice flour. In amylograph analysis, the significantly lowest gelatinization temperature was obtained in dough with XG (P<0.05). XG revealed the highest maximum viscosity while GM revealed the lowest. In viscograph test, the lowest gelatinization temperature and maximum viscosity showed the same result as in the amylograph. Breakdown value was also highest in dough containing XG, but lowest in the control and dough containing HPMC. Setback value was highest in dough containing HPMC, but lowest in dough containing XG. In farinograph analysis, consistency was greatest in dough with HPMC and XG. Hydrocolloids affected water absorption, which was highest in dough containing GM. Development times of dough containing HPMC and XG were low. Stability was lowest in dough with XG. Degree of softening was reduced in dough containing HPMC and GG compared to the control but increased in dough containing XG and GM. Dough containing HPMC and GG showed the largest volume at 3 h of fermentation. Dough with HPMC showed the lowest pH value. Hydrocolloids in this study affected physicochemical properties of dough.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.749-753
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• 2002

The effects of green tea powder (GTP) on the rheological properties of dough and gelatinization characteristics were evaluated by farinograph, extensograph, amylograph and DSC. The flours used were high strength flour (HF: 12.5% protein) and blend of 50% high strength flour and 50% low strength flour (HLF: 10.5% protein). As the amount of GTP increased, water absorption, development time and weakness of the dough decreased for both flours, but dough stability increased only for HLF; the extension of the dough decreased but the resistance to extension increased. The pasting temperature increased and maximum viscosity decreased. On the other hand, with the addition of green tea extract to the wheat starch, transition onset temperature, transition peak temper-ature and enthalpy decreased, demonstrating that catechins in green tea facilitate the starch crystal melting.

• The Korean Journal of Food And Nutrition
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• v.16 no.2
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• pp.105-110
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• 2003

The effect of varietal differences of rice starches by amylose content and gel consistency on the retrogradation behavior was studied. The gel consistency test, which is designed to detect differences in the texture of cooked rice of varieties that have a similar amylose content, had been turned out to be useful in this study. Both Suwon 232 and San Li Cun had higher amylose content, but were greatly different in gel consistency values. The results showed that setback viscosity of rice flour measured in a Brabender amylograph was significantly affected by amylose content as well as gel consistency. Increase in the rigidity modulus (E) of rice starch gels during storage determined by using Texture analyzer indicated that amylose content was an important factor in terms of hardness development The study of Avrami kinetics of retrogradation showed that time constant of rice starch gels was influenced by amylose content, but not by gel consistency.

• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.523-528
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• 1999

The influence of ginseng on the paste or gelatinization properties by amylograph and mixing properties by farinograph of wheat flour and on quality properties color cooking quality textural and sensory properties and reducing microbial population of LL(Long Life) noodles was studied. The contents of ginseng used were from 5% to 10% based on flour weight. The viscosity property of wheat flour with ginseng was increased the initial pasting temperature but the amylograph peak viscosity were decreased in vice versa. The farinograph absorption stability and breakdown were increased by ginseng. The whiteness of Ll nodles manufactured with ginseng was lower than that of control The shear extrusion force and hardness of LL noodles manufactured with ginseng were shown much higher value than those of control. At cooking quality examination of LL noodles manufactured with ginseng weight of cooked LL noodles was decreased but volum was appeared in ice versa,. Extraction amounts of LL noodles manufactured with ginseng during cooking were much smaller than those of control Total count of microorganism of Ll noodles manufactured with ginseng were decreased during storage at 3$0^{\circ}C$ Sensory properties of cooked LL noodles which was manufactured with ginseng showed quite acceptable. Based on the cooking and sensory evaluation test addition of 7.0% ginseng to wheat flour may be suitable for processing LL noodles.