• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.942-949
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• 2005

To improve the textural properties and stabilize the structure and gel matrix of non-waxy rice starch gels, non-waxy rice starch/gum mixture gels were prepared from various food gums, gum arabic, guar, algin, deacyl gellan, xanthan and gellan gums. The morphological and textural properties and freeze-thaw stability of their gels were compared. Rice starch/gum mixture gels with various gums formed a more homogeneous gel matrix with smaller particle size than rice starch gel without Em, but the trends differed depending on the gum types. The textural properties of rice starch/gum mixture gels were changed with the gum types. The shape of the rice starch/gum mixture gel matrix was desirable when mixed with gellan and algin. The textural properties of gels hardened in the rice starch/algin mixture gel and softened in the rice starch/algin mixture gel. The rice starch gels showed V-type crystallinity by x-ray diffractometer, but the peak at $2\theta$ = $20^{o}$ was decreased with increasing gum addition. The freeze-thaw stability increased with increasing gum addition. Gellan and algin were especially effective.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.939-946
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• 1997

Effects of moisture content on the gelatinization and recrystallization of non-waxy and waxy rice starch gels were investigated by differential scanning calorimetry (DSC). The recrystallization rates of the starch gels containing various moisture contents $(40{\sim}70%)$ were analyzed by Avrami equation. The waxy rice starch had higher gelatinization temperature and enthalpy than non-waxy one. The highest degrees of recrystallization in both rice starch gels stored at $4^{\circ}C$ were shown at 40%, and recrystallizations above 80% moisture content were not found. The degree of recrystallization of waxy one was higher than that of non-waxy one in the range of 40 to 60% moisture content. The Avrami exponents (n) of both rice starch gels were near to 1.0 and the time constant (1/k) was increased with increasing moisture content in the range of 40 to 70% moisture content. The recrystallization rate of waxy rice starch gel was slower than that of non-waxy one. The recrystallization of rice starch gels could be explained by the change of ice melting enthalpy during storage. The Wg's, represented the maximum practical amount of plasticizing water, were about 29.9% and 28.2% for non-waxy and waxy rice starch gels, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.358-364
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• 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 $60^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.196-204
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• 2011

Heat-moisture treatment (HMT) was applied to 4 samples of rice flours, Goami (GM), Taeguk (TG), Choochung (CC) and Koshihikari (KSHK), of which amylose contents were 31.5, 32.3, 24.3, and 23.3%, respectively. Wet-milled rice flours were dried, moisture content adjusted to 21, 24, 27 and 30%, respectively, and autoclaved at 100 and $105^{\circ}C$ for 30~90 min. The changes on swelling, solubility, RVA (rapid visco analyser) paste viscosities and gel strength were observed. In GM and TG, peak viscosity (PV) and breakdown (BD) decreased and no peak appeared as moisture and treatment time increased by HMT. In CC, FV increased notably with big increase of PV and setback (SB) by HMT compared to the other rice flours. BD in all the samples decreased as moisture, temperature, and time increased by HMT. RVA pasting properties of HMT GM and HMT TG were changed remarkably under conditions of moisture 21%, $100^{\circ}C$ and 30 min whereas for HMT CC and HMT KSHK, higher temperature or more time was required at the same mois ture levels. The swelling power, solubility and gel strength increased by HMT. Gel strength correlated positively with SB (r=0.78, p<0.01) and negatively with BD (r=-0.71, p<0.01) and PV (r=-0.36, p<0.05) resulting from strengthening the structure of starch granules in rice flours by HMT.