• Korean Journal of Food Science and Technology
• /
• v.23 no.1
• /
• pp.116-121
• /
• 1991

The effects of water contents and surfactants, sodium stearoyl-lactylate, sucrose ester and distilled monoglyceride(Dimodan) on wheat starch gelatinization and retrogradation were studied by differential scanning calorimetry. The endothermic peak patterns of starch varied with water content of starch. When water content was less than 30%, gelatinization did not occur. The onset temperature of gelatinization peak of native starch was $59{\sim}60^{\circ}C$ and that of endothermal peak of retrograded starch was $50{\sim}55^{\circ}C$. The enthalpy value of retrograded starch were greatest in the $40{\sim}50%$ water content. In the presence of surfactants, gelatinization temperatures shifted slightly to higher temperatures. DSC endothermal enthalpies of the amylose-lipid complex increased. The degree of retrogradation in starch was lower with surfactant than without surfactant, but enthalpy of amylose-lipid complex did not change during storage.

• Applied Biological Chemistry
• /
• v.34 no.2
• /
• pp.187-189
• /
• 1991

Gelatinization temperatures of upland and lowland waxy brown rice starches annealed at $25^{\circ}C$ and $60^{\circ}C$ for 24hr were investigated with differential scanning calorimetry No annealing effect was observed at low temperature. The upland rice starch showed narrower range of gelatinization temperature upon annealing treatment at $60\circ}C$ compared with the lowland rice starch. The enthalpy of gelatinization was not changed in case of the upland rice starch but was increased in case of the lowland one upon annealing.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.1
• /
• pp.40-47
• /
• 1993

Gelatinization properties of the air-dried sediment of cowpea were investigated. The water-binding capacity of cowpea flour was drastically increased over the temperature range of 52~55$^{\circ}C$. The percent transmittance of flour suspension was linearly increased at temperature between $65^{\circ}C$ to 75$^{\circ}C$. The gelatinization temperature determined by differential scanning calorimetry was 63.4~76.$0^{\circ}C$. Cowpea flour showed a single-stage of swelling and a low solubility pattern. The minimum moisture content required for the gelatinization was 37.0% . The amylograph peak viscosity was greatly influenced by concentration of the flour, but was not affected by heating temperatures (85~94$^{\circ}C$) at a given concentration. The 20 min height and cold viscosity at 3$0^{\circ}C$ at a fixed concentration was negatively correlated (p<0.05) with heating temperatures.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.39 no.4
• /
• pp.14-20
• /
• 2007

The effects of blending starches with different gelatinization temperatures on the development of ply-bond strength were systematically investigated using a three component mixture design technique. Oxidized corn starches with different gelatinization temperatures were blended with natural corn starch and sprayed for plybonding. Optimum blend ratio for maximizing plybond strength improvement for the starch blends was 40% of natural starch, 27% of oxidized starch with low gelatinization temperature and 33% of oxidized starch with high gelatinization temperature. Starch granules with the lowest gelatinization temperature gelatinizes at the lowest temperature, while the natural corn starch gelatinizes at later stage of drying. The improvement of plybond strength with starch blends were verified on machine trial as well. Plybond strength improvement obtained from the machine trial was lower than that achievable with handsheets, which was attributed to the lower internal bond strength of the linerboards made from recycled fibers.

• Korean Journal of Food Science and Technology
• /
• v.34 no.2
• /
• pp.343-345
• /
• 2002

The study was investigated hot-water soluble on waxy black and waxy rice flours according to gelatinization temperatures and heating time. The hot-water soluble contents of both samples were increased during heating time at $90^{\circ}C$. The waxy black and waxy rice flours solutions according to gelatinization temperatures ($80^{\circ}C,\;90^{\circ}C,\;95^{\circ}C\;and\;98^{\circ}C$) were heated for 10, 20 and 30 min. Determination of elution patterns of rice flours was used by Sepharose CL-2B column. As a result, the elution patterns were eluted the most in void volume ($V_0$) and the elution patterns of the hot-water solubles were increased according to heating time and gelatinization temperatures.

• Korean journal of food and cookery science
• /
• v.16 no.5
• /
• pp.431-436
• /
• 2000

Gelatinization properties of potato starches which were prepared by steeping at 10 ${\pm}$ 1$^{\circ}C$ or 25 ${\pm}$ 1$^{\circ}C$ for 11 days were investigated. The pasting and initial gelatinization temperatures measured by rapid visco-analyzer (RVA) were increased, but the peak and trough viscosities of potato starch were decreased by steeping. The onset temperature, peak temperature, conclusion temperature, and enthalpy of gelatinization were increased by steeping as measured by DSC. The contents of hot-water-soluble carbohydrate and amylose in potato starch were decreased by steeping.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.37 no.1
• /
• pp.28-36
• /
• 1992

Fifty rice varieties were tested for alkali digestibility of milled rice grain at four different KOH levels, and twenty-four varieties selected were tested again for alkali digestibility at different degrading times and KOH levels. Gelatinization rate at several heating times and heating temperatures, and water absorption rate at 21$^{\circ}C$ and 77$^{\circ}C$ water temperatures were observed using rice samples of twenty-four varieties to clarify the relationship between alkali digestibility response, gelatinization rate and water absorption rate. Varietal difference of ADV in Japonica and Tongil tye rices was biggest at KOH 1.2%, but it was better to test at KOH 1.2% and 1.4% levels to know the exact alkali digestibility response of rice varieties. Rice varieties tested could be classified into three groups, low, intermediate and high, based on their alkali digestibility response at four KOH levels, and most of Korean cultivated rice varieties were belonged to intermediate or high ADV group. Varietal variation was also found in alkali degrading response at different soaking times in alkali solution. Low ADV varietal group showed higher gelatinization temperature and needed longer heating time for complete gelatinization compared with intermediate or high ADV group. Same trends was found between intermediate and high ADV groups, but varietal variation in the same ADV group was also found in gelatinization temperature and heating time needed for complete gelatinization of rice grain. Water absorption rate of low ADV group was lower than intermediate or high ADV group both at 21$^{\circ}C$ and 77$^{\circ}C$ water temperatures, and intermediate ADV group showed lower absorption rate than high ADV group only in initial water absorption stage at 21$^{\circ}C$.

• Journal of Applied Biological Chemistry
• /
• v.66
• /
• pp.90-97
• /
• 2023

The effect of citric acid on rice starch gelatinization and low-temperature (4 ℃) storage was studied in order to produce rice cake with a lower retrogradation rate. A citric acid solution in the ratio of 0, 0.5, 1.0, and 1.5% (w/w) of the water used during production was utilized. The gelatinization properties, gel strength, thermal properties, and texture analysis were evaluated to determine the retrogradation rate. The result showed that acid hydrolysis occurred in samples treated with citric acid. Thus, increasing citric acid decreased gelatinization temperature (58.63±1.98 to 45.84±1.24 ℃). The moduli of elasticity increased with increasing citric acid concentration, indicating an increased gel strength. Thermal analysis of starch showed that the onset, peak, and conclusion temperatures of retrogradation were increased significantly with the storage period and decreased with citric acid concentration. After 72 h of low-temperature storage (4 ℃), the retrogradation rate was lowest in the rice cake with 1.5% citric acid solution, with an increased ratio of 12.01 to 13.60% compared to the control sample, with a ratio of 12.99 to 43.54%. This shows a high retrogradation rate in the control sample. Additionally, sensory properties and retrogradation ratio suggest that the addition of 1.0% citric acid solution during rice cake production is efficient in retarding the retrogradation without an adverse effect on the rice cake modeling and acceptance.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.42 no.3
• /
• pp.344-351
• /
• 1997

The experiment was conducted to examine the varietal variation in gelatinization of rice flour and adaptability to rice bread processing, and the interrelation among the relevant properties. IR 44 showed the lowest temperature of gelatinization onset(T$_{o}$ ) and the highest gelatinization enthalphy(ㅿH) measured by differential scanning calorimetry (DSC). The following lower T$_{o}$ was found with the order of Suweon 230＜Pusa-33-30＜T(N) 1, Daeribbyeo 1 and the next higher ㅿ.H was followed by the order of Pusa-33-30＞Suweon 230. IRAT 177 revealed the highest temperature of gelatinization onset and conclusion(T$_{c}$) and the following higher T$_{c}$ was found with the order of Pusa-33-30＞AC 27＞Nonganbyeo. The varietal range of T$_{o}$ and T$_{c}$ was 50.0~72.5$^{\circ}C$ and 70.2~87.4$^{\circ}C$, respectively. The rice materials tested can be classified by scatter diagram on the plane of upper two principal components contracted from DSC thermogram and various characteristics relevant to processing and sensory preference of rice bread by principal component analysis. AC27, Suweonjo and IR 44 among high-amylose rices showed better suitability to rice bread processing. The temperatures of gelatinization peak and conclusion of rice flour checked by DSC were significantly negatively associated with springiness of rice bread. The most properties relevant to processing and sensory preference of rice bread such as hardness, moistness, springiness, cohesiveness, specific loaf volume and distribution or size of air cell revealed the close correlation between each other.other.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.3
• /
• pp.358-364
• /
• 2001

The physiochemical properties and interactions between porcine blood and waxy rice were determined. Addition of calcium chloride (0.15%) improved acceptability of blood cake and increased the gelatinization degree of waxy rice. The water-holding capacity of porcine blood gel (blood/water=60/40, v/v), extent of absorption and gelatinization of waxy rice, and scanning electron microscopy showed that blood protein matrix and waxy rice are competitors for holding water in the cooking procedure. Non-haem iron content increased linearly (R=0.95) when heating temperature rose. The presence of blood proteins caused increasing of peak temperature (Tp) of gelatinization in differential scanning calorimetric thermal gram, The microstnlcture of plasma proteins and haemoglobin appeared continuous changes, and interacted with surface of waxy rice flour in terms of network and mosaic form, respectively. The electrophoretic patterns revealed an interaction between plasma proteins and waxy rice glutelin and haemoglobin when heated could be found at temperatures above $60^{\circ}C$.