• Journal of Nutrition and Health
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• 제29권6호
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• pp.615-621
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• 1996

Experiments were carried out in humans to assess the relationship between viscosity and post-prandial glucose response of soluble fibers. Eight(3 male and 5 female) healthy individuals were tested for their glucose response after taking control meals or 3 test fiber meals of different viscosities. Meal viscosity of the test food was adjusted to be between 200 and 70, 000 cps. There was a significant increase in post-prandial glucose response(p=0.01) in control meals by solely increasing the volume of water. Fiber with the highest viscosity konjac mannan demonstrated the lowest relative glucose response(70.1$\pm$6.6), followed by medium viscosity xanthan (79.3$\pm$8.7)and low viscosity psyllium (86.3$\pm$10.5). The difference is significant at the level of p<0.05. However, no significant difference in relative glucose response of the same fiber was found when the 4 levels of water were added to make different meal viscosity of each fiber (p=0.476). This result suggested that hypoglycemic action of soluble dietary fibers is related to fiber viscosity rather than meal viscosity.

• 한국식생활문화학회지
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• 제24권2호
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• pp.206-211
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• 2009

The purpose of this study was to investigate the effect of shrimp flour on quality characteristics of dumpling shell. Dumpling shell samples were prepared with wheat flour along with the addition of different amount of shrimp flour, followed by functional measurements and sensory evaluations. According to amylograph data, the composite shrimp flour/wheat flour samples had increased gelatinization temperature with increasing shrimp flour content, while initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity were reduced. In terms of color values, L value decreased, but a and b values increased with increasing shrimp flour content. Furthermore, the addition of shrimp flour increased hardness and decreased chewiness in all samples. Overall, sensory evaluations proved that dumpling shell with 10% added shrimp flour was preferred over the other samples.

• 한국식품조리과학회지
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• 제24권1호
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• pp.23-30
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• 2008

Sulgidduk samples made with additions of 2, 4, 6, 8, and 10% Houttuynia cordata Thunb. powder, and a control were examined for quality characteristics such as moisture content, water activity, color, gelatinization properties, textural characteristics, and sensory qualities in order to determine the optimal ratio of Houttuynia cordata Thunb. powder in the formulation. The moisture contents among the samples ranged from 41.98% to 44.97%, and increased as the content of Houttuynia cordata Thunb. powder increased. The water activities of the samples were not significantly different. As the Houttuynia cordata Thunb. powder content increased, the redness and yellowness of the samples also increased, but lightness decreased. For the gelatinization properties, the additions of Houttuynia cordata Thunb. powder caused decreases in peak viscosity (P) and holding strength viscosity (H). Furthermore, final viscosity (F), setback, and time to peak viscosity decreased with increasing Houttuynia cordata Thunb. powder content; however, breakdown and temperature to peak viscosity were not significantly different among the samples. Hardness and gumminess decreased with increasing Houttuynia cordata Thunb. powder content, and adhesiveness, cohesiveness, chewiness, and resilience also tended to decrease; however, springiness was not significantly different among the samples. In the consumer acceptance test, as the content of Houttuynia cordata Thunb. powder increased, the scores of all evaluated characteristics decreased; while the characteristic intensity ratings showed the reverse effect, and the 2 and 4% Houttuynia cordata Thunb. powder samples obtained fairly good scores. In conclusion, the results indicate that adding $2{\sim}4%$ Houttuynia cordata Thunb. powder to Sulgidduk is optimal, providing good physiological properties and reasonably high overall consumer acceptability.

• 한국식품조리과학회지
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• 제30권5호
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• pp.526-530
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• 2014

본 연구에서는 선식 제조 중 원료의 로스팅 공정이 관능적으로 최종 제품의 분산성을 낮추고 점성을 증가시킨 원인을 기계적 물성 측정을 통해 규명하고자 하였다. 현미를 로스팅하여 첨가한 선식들은 대조군에 비해 입자크기가 증가하였으며, 이러한 변화는 주로 직경 $1{\mu}m$ 이상의 영역에서 관찰되었다. 로스팅이 선식 분말의 분산성 자체를 감소시키기 보다는 침강속도를 증가시킴으로써, 분산 상태를 유지하는 시간을 단축시킨 것으로 생각된다. 현미를 증자 건조하는 동안 전분 입자의 붕괴와 수분 증발로 다공성 구조가 형성되므로, 선식을 물과 혼합하면 물이 빠른 속도로 흡수된 것으로 사료된다. 특히, 로스팅한 선식들은 대조군보다 물 결합력이 더 높아, 흐름을 유발하는 데 소요되는 힘 또한 증가되어, 대조군에 비해 점도가 높아진 것으로 해석되었다.

• Applied Biological Chemistry
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• 제39권3호
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• pp.165-171
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• 1996

볏짚으로부터 분리한 Bacillus sp. K-1과 그 변이주 KM-21과 KM-83이 생산하는 biopolymer들의 물성학적 성질을 비교 조사하였다. 은도에 따른 biopolymer의 겉보기 점도는 온도가 높아짐에 따라 감소하였으며, $20^{\circ}C$일 때에 비해 $80^{\circ}C$일 때 KM-21 균주가 생산하는 biopolymer는 1.7배, K-1균주의 biopolymer는 2.7배, KM-83 균주의 biopolymer는 1.9배 정도로 낮은 점성을 보였다. Biopolymer 용액의 점성은 농도가 증가함에 따라 크게 증가하여 6%의 농도에서 가장 높게 나타났으며, 2%, 4%, 6% 모두 pseudoplastic특성을 나타내어 농도에 대한 의존성이 매우 높았다. 6%의 농도일 때 2%의 농도와 비교해서 전단 속도가 $93\;sec^{-1}$ 일 때 KM-21은 26배, K-1은 56배, KM-83은 28배로 모균주의 biopolymer인 K-1이 가장 높은 점성을 보었다. pH에 따른 점도 변화는 pH7.0에서 최고를 보였으며, 알칼리성 조건일 때에 비해 산성조건에서 상대적으로 낮은 값의 점성을 보였다.

• 한국축산식품학회지
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• 제18권3호
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• pp.209-215
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• 1998

Effects of protein concentration, ionic strength, pH, and temperature range on the heat-induced denaturation of salt soluble protein extracted from spent layer meat were investigated. Viscosity of salt soluble protein heated at 65$^{\circ}C$ for 30 min began to increase sharply above 7 mg/ml of breast protein concentration, and above 21 mg/ml of leg protein concentration, respectively. Both turbidity and viscosity showed the highest value in cooked protein solution with pH 6.0 and 1% NaCl. The turbidity of salt soluble protein started to increase continuously from 40$^{\circ}C$ to 80$^{\circ}C$. The viscosity increased rapidly from 45$^{\circ}C$ to 60$^{\circ}C$ in breast protein, and increased from 50$^{\circ}C$ to 55$^{\circ}C$ in leg protein, respectively, and then kept relatively constant. Breast protein had higher viscosity than leg protein during heat-induced gelation. Therefore, salt soluble protein from spent layer meat was associated with denatured protein (turbidity change) prior to gelation (viscosity change) during heating. Breast protein showed lower thermal transition temperature, and better gel formation than leg protein during heating.

• 한국식품과학회지
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• 제29권6호
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• pp.1151-1157
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• 1997

정제된 다당류 메틸란을 여러 가지 화학 방법에 의해서 분석한 결과 79%의 당이 존재하였고 6%의 단백질과 16%의 유기산이 존재하였다. 배양시간이 증가함 따라 pyruvic acid와 uronic acid 같은 산의 함량이 34시간의 10%에서 72시간에서는 17%까지 증가하였고 이에 따라 점도도 증가하였다 메틸란 내의 산의 함량이 점도에 중요한 인자로 생각되어 주요 유기산인 uronic acid와 pyruvic acid의 함량과 점도와의 관계를 살펴보았다. 생물학적 및 과학적 변형을 통하여 pyruvic acid의 함량이 변화된 메틸란을 이용하여 pyruvic acid의 함량과 점도와 관계를 조사하였다. Pyruvic acid함량이 증가할수록 겉보기 점도와 고유 점도가 증가하였고 pyruvic acid의 함량이 1% 증가할 경우 약 290 cp의 겉보기 점도와 약 6 dL/g의 고유 점도가 증가하였다. 생물학적 및 화학적 변형을 통하여 uronic acid의 함량이 변화된 다당류에서 uronic acid 함량과 점도와 관세를 살펴보았다. 메틸란 내의 uronic acid의 함량이 증가할수록 점도가 증가하여 uronic acid의 함량이 1% 증가할 경우 약 85 cp의 겉보기 점도와 약 1.5 dL/g의 고유 점도가 증가하였다. 이러한 결과로부터 메틸란의 점도 증가는 다당류 내의 유기산의 함량이 증가할수록 증가되고 메밀란의 점도 증가는 uronic acid보다 pyruvic acid에 더 기인함을 알 수 있었다.

• Food Science and Biotechnology
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• 제15권1호
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• pp.77-81
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• 2006

The dextransucrase activity of microorganisms which were identified as contributing to the fermentation of jeungpyeon made with yeast was measured. The dextran generated during fermentation was quantified and the viscosity changes were measured. The mechanism of network structure formation was clarified by observing the inside of the network structure over the fermentation periods ranging from 1 to 7 hr using scanning electron microscopy (SEM). The pH of jeungpyeon batter decreased significantly as the fermentation proceeded, whereas the viscosity increased. The identified lactic acid bacteria (LAB) were Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus pentosaceus, Tetragenococcus halophilus, and Leuconostoc mesenteroides subsp. dextranicum. The yeast was identified as Saccharomyces cerevisiae A/Tor. Pretorien. The dextransucrase extracted from those microorganisms showed high activity. On the other hand, the amount of dextran generated from the batter increased significantly beyond 2 hr of fermentation, and the viscosity increment showed a similar trend. The SEM photos showed that the most homogeneous fine network structure was observed in the batter fermented for 2 hr. Therefore, we assumed that the dextran that was generated by microorganisms during fermentation interacted with the components of the batter to increase the stability of the network structure.

• Preventive Nutrition and Food Science
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• 제4권3호
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• pp.175-179
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• 1999

To develop a production method for modified starches with less pollution, pH adjustment and gamma irradiation were applied to commerical corn starch. Blue values were significantly decreased , while alkali number, optical transmittance and solubility markedly increased when gamma irradiation was applied to pH 2 adjusted corn starch. Water binding capacity and swelling power at pH 5 were the highest among the samples. Gelatinization viscosity was considerably affected by gamma irradiation and pH of the starch. Gamma irradiation of pH 2 adjusted starch showed the lowest peak viscosity and the best cooling stability among the tested samples . Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability seems feasible by controlling the pH of the starch and gamma irrdiation.

• Korea-Australia Rheology Journal
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• 제12권3_4호
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• pp.175-179
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• 2000

Rheological properties of chitosan solutions were investigated as a function of polymer concentration. The viscosity curves for chitosan solutions consisted of two distinct viscosity regions, the Newtonian zero-shear viscosity (η$_{0}$) region and the shear rate dependent apparent viscosity (η$_{app}$) region. The shear rate dependence of viscosity was more clearly observed at higher chitosan concentrations. The critical coil overlap parameter (C＊〔η〕) was determined to be approximately 3.2 from a plot of zero-shear specific viscosity η$_{sp,0}$ vs coil overlap parameter (C〔η〕), which was lower than C〔η〕4.0 reported for other random coil polysaccharides. It was also found that the slope of η$_{sp,0}$ vs C〔η〕 was 3.9 at concentrated C〔η〕>C＊〔η〕domain, while 1.2 at dilute C〔η〕$_{0}$ ${\gamma}$/${\gamma}$$_{0.8}$ relation.ion.n.n.