• Title/Summary/Keyword: gelatinization

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Effects of Rice Bran Dietary Fiber Extract on Gelatinization and Retrogradation of Wheat Flour (미강 식이섬유 추출물이 밀가루의 호화 및 노화에 미치는 영향)

  • Kim, Young-Soo;Ha, Tae-Youl;Lee, Sang-Hyo;Lee, Hyun-Yu
    • Korean Journal of Food Science and Technology
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    • v.29 no.3
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    • pp.464-469
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    • 1997
  • Rapid visco-analyzer (RVA) and differential scanning calorimetry (DSC) were used to study the effect of rice bran dietary fiber extract on gelatinization and retrogradation of wheat flour. The addition of rice bran dietary fiber extracts from various heat treated bran into wheat flour caused to increase the pasting temperature, peak viscosity and final viscosity of RVA measurements. For gelatinization measured with DSC, mixtures of wheat flour and rice bran dietary fiber extract had slightly higher To (onset temperature) and Tp (peak temperature) values than those of control (wheat flour), and wheat flour/defatted rice bran dietary fiber extract mixture had the lowest enthalpy value. In comparison with gelatinization, the retrogradation endotherm of mixtures stored at $4^{\circ}C$ up to 4 weeks occurred at about $20^{\circ}C$ lower temperatures than gelatinization endotherm with broader shape and well-defined thermograms with storage time. The retrogradation of wheat flour was retarded greatly by addition of rice bran dietary fiber extract, and there was no big difference between 5% and 10% additions.

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Comparison of Differential Scanning Calorimetry with Enzymatic Method for the Determination of Gelatinization Degree of Corn Starch (DSC에 의한 전분의 Endothermic peak와 효소분석법에 의한 호화도 비교)

  • Lee, Boo-Yong;Mok, Chul-Kyoon;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.25 no.4
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    • pp.400-403
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    • 1993
  • Gelatinization degrees of torn and waxy corn starches in the low-moisture environment were determined by DSC thermogram and enzymatic analysis, the results were compared each other As the moisture content increased from 20% to 70%, the enthalpy of endothermic peak of starch increased linearly in DSC thermograms. When the moisture content exceeded above 70%, the DSC enthalpy of starch remained constant in DSC thermogram. The enthalpies for gelatinization of corn and waxy corn starches were 3.23 cal/g and 4.2 cal/g, respectively. When gelatinization degrees of starches were measured by enzymatic analysis, the gelatinization degree increased linearly as the moisture content increased from 20% to 80%. A linear correlation between DSC and enzymatic analysis was obtained only when the moisture content was under 70%.

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Effect of ${\beta}-Glucan$ on Gelatinization of Barley Starch (${\beta}-Glucan$이 보리 전분의 호화에 미치는 영향)

  • Choi, Hee-Don;Seog, Ho-Moon;Kim, Sung-Ran;Park, Yong-Kon;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.35 no.4
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    • pp.545-550
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    • 2003
  • The effect of ${\beta}-glucan$ on gelatinization of barley starch was studied. By the rapid visco-analyzer measurement, gelatinization of starch became rapid and viscosity increased largely on the RVA pattern by addition of ${\beta}-glucan$ to starch. The results of differential scanning calorimeter showed that molecular structure of starch was getting stabilized through shifting up of gelatinization temperature and increase in enthalpy by addition of ${\beta}$-glucan. X-ray diffraction pattern also showed the same results as differential scanning calorimeter. But it was revealed that addition of ${\beta}$-glucan to starch didn't affect characteristics such as microscopic observation, solubility, swelling power, and iodine binding properties during gelatinization of starch.

Effects of Various Salts on the Reheating Behavior of Retrograded Rice Starch and Cooked Rice

  • Han, Sung-Hee;Kim, Bo-Reum;Lee, Seog-Won;Rhee, Chul
    • Preventive Nutrition and Food Science
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    • v.16 no.2
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    • pp.157-164
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    • 2011
  • The influence of sodium salts and chlorides at various concentrations (0.05, 0.10, 0.50, and 1.00%) on the reheating behavior of retrograded rice starch and cooked rice was investigated. The degree of gelatinization of the all retrograded rice starch gels and the cooked rice containing sodium salts and chlorides increased after reheating compared to the starches without salt. Gelatinization also showed an increasing trend as the concentration of sodium salts and chlorides increased. The increase of gelatinization after reheating the samples containing sodium salts and chlorides was greater than 38.0%. The reheated retrograded rice starch and cooked rice containing $Na_3PO_4$ showed the lowest set back value and retrogradation rate constant. Among all the samples, the cooked sample containing $Na_3PO_4$ showed the highest increment of gelatinization after reheating. Also, this same sample showed the lowest retrogradation degree.

Effects of Particle Size and Gelatinization of Job's Tears Powder on the Instant Properties

  • Han, Sung-Hee;Park, Soo-Jea;Lee, Seog-Won;Rhee, Chul
    • Preventive Nutrition and Food Science
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    • v.15 no.1
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    • pp.67-73
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    • 2010
  • The effects of particle sizes (small, medium and large sizes) and gelatinization treatment on the changes of the instant properties of Job's tears powder were investigated. The degree of gelatinization on the different particle size samples of Job's tears powder was the highest in the small particle size, and it also showed an increasing trend regardless of pregelatinizing whether it is or not as the particle size decreased from large particle size to small particle size. The water solubility index of the pregelatinized samples was high compared to that of ungelatinized samples regardless of particle size and temperatures. The water absorption and swelling power increased as particle size and temperature were increased. The dispersibility and sinkability of ungelatinized sample was increased as particle size and temperature were increased and it also showed lower value regardless of particle size and temperature. However, the dispersibility and sinkability of pregelatinized samples were shown to have the opposite result, such that the smallest particle size of pregelatinized sample had the lowest sinkability (11.3%). The turbidity of the pregelatinized small particle size was the highest by a factor of 1.08.

Gelatinization Properties of Heat-Moisture Treated Potato and Sweetpotato Starches (수분 열처리한 감자 및 고구마전분의 호화 특성)

  • Kim, Sung-Kon;Lee, Shin-Young;Park, Yong-Kon
    • Korean Journal of Food Science and Technology
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    • v.19 no.5
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    • pp.435-440
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    • 1987
  • Gelatinization properties of heat-mositure treated potato and sweet potato starches were investigated. Water-binding capacity of starch was increased by heat-mositure treatment, which was more pronounced in sweet potato starch. Blue value was not affected by the treatment. Amylograph viscosities were decreased by heat-mositure treatment, which was more pronounced in potato starch. Critical concentration of NaOH for gelatinization of starch increased as moisture level increased. Gel volume of starch upon KSCN gelatinization was higher in potato starch. Gelatinized starches showed Binghamapseudoplastic behavior. Consistency index and yield stress were drastically decreased upon heat-moisture treatment.

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Rheological Properties of Gelatinization of Rice Starch (쌀 전분 호화중의 리올로지 특성)

  • Lee, Shin-Young;Cho, Hyung-Yong;Kim, Sung-Kon;Lee, Sang-Kyu;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.16 no.3
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    • pp.273-278
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    • 1984
  • Changes in rheological properties of rice starch-water systems during the gelatinization were evaluated with the tube viscometer at temperatures between 50 and $85^{\circ}C$ and for the concentrations ranging from 3-5% rice starch. The flow consistency index increased exponentially with time at a particular temperature while being linearly dependent upon the concentration. The gelatinization rate measured by rheological method followed Arrhenius type equation. The value of activation energy of gelatinization for 5% rice starch was about 25 kcal/g mol.

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Characteristics of Dry and Moist Type Sweet Potato Starches (분질 및 점질 고구마 전분의 특성)

  • Shin, Mal-Shick;Ahn, Seung-Yo
    • Korean Journal of Food Science and Technology
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    • v.20 no.3
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    • pp.412-418
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    • 1988
  • Granular shapes and sizes, physicochemical priperties and gelatinization patterns of sweet potato starches from Wonki(the dry type) and Chunmi(the moist type) were investigated. Starch granules of sweet potatoes were round. Granule sizes of Wonki starch were mainly $11{\mu}m$ and those of Chunmi starch were $12{\mu}m\;and\;17{\mu}m$. Wonki starch had lower water binding capacity and swelling power than Chunmi starch. But Wonki starch had higher amylose content, gelatinization temperature, miture content for gelatinization and temperature for gelatinization than Chunmi starch.

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Physicochemical Characteristics of Starches in Rice Cultivars of Diverse Amylose Contents

  • Yoon, Mi-Ra;Chun, A-Reum;Oh, Sea-Kwan;Hong, Ha-Cheol;Choi, Im-Soo;Lee, Jeong-Heui;Cho, Young-Chan;Kim, Yeon-Gyu
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.3
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    • pp.226-232
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    • 2012
  • Through the sampling four rice cultivars with differing amylose contents, the relationship between the structural and gelatinization properties of endosperm starches was analyzed. These rice varieties exhibited different chain length distribution ratio within the amylopectin cluster as well as varing amylose levels. The proportion of amylopectin short chains of in Goami cutlivars was higher than the other varieties, whereas the Goami 2 which shows amylose extender mutant properties in the endosperm showed the highest proportion of long chains. In X-ray diffraction analysis of rice starches, the Goami 2 variety displayed a B-type pattern whereas the other varieties were all A-type. Among the cultivars with high and normal rice starch levels, those with the higher amylose contents showed distinctly lower swelling. Goami 2 rice was found to have the highest onset and peak gelatinization temperature from the differential scanning calorimetry results. The four rice cultivars under analysis also showed different rates of hydrolysis by amyloglucosidase. These findings suggest that the composition and chemical structure of the starch content is a major determinant of both the gelatinization and functional properties of rice.

Physicochemical Properties of Japonica Non-Waxy and Waxy Rice during Kernel Development

  • Kim, Sung-Kon;Jung, Sun-Ok
    • Food Science and Biotechnology
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    • v.15 no.2
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    • pp.289-297
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    • 2006
  • In this study we examined the changes in weight and dimension, protein and amylose contents, and pasting properties of brown rice flour, as well as the gelatinization properties of starch, from two non-waxy japonica cultivars and one waxy japonica cultivar planted in an experimental field in 2002 under the same fertilizer conditions. The weight of both rough and brown rice increased consistently up to 42 days after flowering (DAF) for the non-waxy rice and to 35 DAF for the waxy rice. The changes in dimension of the brown rice kernel indicated that the length was maximized first, followed by breadth and then thickness. The protein content of the non-waxy rice remained fairly constant, but that of the waxy rice decreased by about 1% after 14 DAF. The amylose content of the non-waxy brown rice flour increased, but that of the waxy brown rice flour decreased during kernel development. As the kernel developed, the peak viscosity of the non-waxy rice flour increased up to 35 DAF, after which it decreased, whereas that of the waxy brown rice flour increased consistently. The gelatinization temperature of starch also increased in the waxy rice during kernel development up to 21 DAF. The gelatinization enthalpy of starch, however, increased in all rice cultivars throughout the kernel development.