• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.2
• /
• pp.311-314
• /
• 2003

As a research on the practical approaches of gamma irradiation for the reduction of egg allergy, cakes including gamma-irradiated egg white were manufactured, and rheological characteristics and sensory qualities of the cakes were evaluated. Egg white was separated from whole egg and then gamma-irradiated with the absorbed dose of 10 or 20 kGy White layer cake, pound cake and sponge cake were made with irradiated egg white and used to the subsequent experiments. Firmness of all samples containing irradiated egg white was higher than that of control. Retrogradation of pound and sponge cakes containing irradiated egg white was delayed, and the result showed that the usage of irradiated egg white was better at the point of rheological storage ability. Effects of irradiated egg white on the sensory quality were different depending onto the properties of each product. Radiation off-odor was observed in the a11 samples containing irradiated egg white. To maintain the sensory Qualify, adequate methods such as masking effects should be developed during manufacture.

• Korean Journal of Food Science and Technology
• /
• v.23 no.3
• /
• pp.317-324
• /
• 1991

Gelatinization behaviours and gel properties of hydroxypropylated corn starches (HPCS) were investigated with differential scanning calorimeter, amylograph and rheometer. Gelatinization temperature of HPCS decreased as degree of substitution increased. The retrogradation of corn starch was greatly reduced by hydroxypropylation, indicating that the association of starch molecules was sterically hindered by hydroxypropyl groups. In HPCS, gel was formed slowly and gel strength decreased resulting in soft and sticky texture. Texture profiles of HPCS gels were similar to those of tapioca and waxy corn starch. HPCS has shown a remarkable increase of paste transparency compared to native corn starch.

• Korean journal of food and cookery science
• /
• v.12 no.2
• /
• pp.200-206
• /
• 1996

This study was carried out in order to investigate the effect of additives on Jeungpyun (fermented and steamed rice cake) Preparation. Soy bean flour, whole milk Powder, skim milk Powder, egg yolk, egg white, and mugwort were added in the Preparation of Jeungpyun. There were not significantly difference in loaf volume between control and experimental groups addfd egg yolk, egg white and mugwort. In sensory evaluation, the hardness of Jeungpyun containing of soy bean flour, milk Powder, and egg were lower than control The Jeungpyun containing mugwort was more bitter and harder than the control. The rheological properties measured by texturometer were significantly different among the Jeungpyun added with different kinds of additives. The hardness was significantly lower in Jeungpyun containing whole milk Powder and soy bean flour and springiness was higher in mugwort Jeungpyun compared with the control. In 4$^{\circ}C$ storage, retrogradation of Jeungpyun assessed from hardness measured by texturometer was delayed by addition of soy bean flour and whole milk powder.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.3
• /
• pp.395-402
• /
• 2005

White layer cakes with 10-50% content of domestic millet and waxy millet were carried out to determine how the content of millet and waxy millet affected Quality and properties of a product. The 10% content of waxy millet resulted in the greatest volume, which decreased with the increase in the content of millet and waxy millet; up to 40% content of millet and waxy millet made no significant difference in weight from the control one. The specific loaf volume decreased with the increase in the content of millet and waxy millet. In terms of crum color, as the content of millet and waxy millet increased, the value of L tended to decrease, making it darker, and there was a significant increase in the value of a and b. As for crust color, the value of L, a, and b tended to increase with the increase in the content of millet and waxy millet, making it darker, but with no significant difference from the control one. In terms of texture, 10% content of millet and 10-20% content of waxy millet made no significant difference in hardness from the control one; as for retrogradation, waxy millet tended to make greater increase in hardness than millet. 5℃ storage resulted more rapidly in retrogradation than 25℃. The sensory evaluation showed that with the increase in the content, waxy millet, millet, and the control in order served to make it darker and harder in terms of external properties, with small pores, uneven texture, and reduced flavor in terms of internal properties. There was no significant difference between the cake with 10-20% content of millet and waxy millet and the control one in making a white layer cake by adding millet and waxy millet.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.3
• /
• pp.474-483
• /
• 2015

The textural properties of breads containing midified starches such as pregelatinized waxy corn starch, acetylated potato starch and hydroxypropylated tapioca starch, were investigated to determine the optimum addition level of modified starches. Effects of modified starches on dough properties were investigated through a farinogram and amylogram based on the different additional levels of modified starches (3%, 6%, 9%, 12% and 15% of flour content). Moisture contents and firmness values were measured to investigate the degree of retrogradation at 0 h, 36 h and 72 h after production. The levels of moisture contents were highest upon addition of pregelatinized waxy corn starch followed by acetylated potato starch and lowest upon addition of hydroxypropylated tapioca starch. Overall, higher moisture contents resulted in lower firmness levels. The preference scores by type of modified starch were highest upon addition of 9% hydroxypropylated tapioca starch, 3% pregelatinized waxy corn starch, and 6% acetylated potato starch, respectively. Preference scores were significantly correlated with textural properties such as volume, absorption, stability and weakness (p<0.01).

• Korean journal of food and cookery science
• /
• v.22 no.2 s.92
• /
• pp.147-157
• /
• 2006

To improve the properties of non-waxy rice flours for baking, soaked-wet milled rice flour (SWRF) was adjusted moisture content (MC) to 30 and 50 % and heated at 50 and $70^{\circ}C$ in a shaking water bath for 6 and 18 hrs, respectively. Moisture-heat treated rice flours were investigated with regard to particle size distribution, and morphological, physicochemical and pasting properties for comparing dry and wet milled flours. The particle size of rice flour treated with 30% MC was distributed between $4-20{\mu}m\;and\;100-200{\mu}m$, like SWRF. The particles above $200{\mu}m$ in the flour were produced at higher heating temperature. By SEM, starch granules were found in the rice flours treated with 30% MC, who whereas aggregated starch granules were shown in the flours treated with 50% MC. Moisture-heat treatment using higher MC and heating temperature decreased the lightness and increased the yellowness of non-waxy rice flours. Water binding capacity of 30% moisture treated rice flour was similar to that of SWRF. In the same moisture treated rice flour, swelling power was higher, but solubility was lower at $50^{\circ}C$ than at $70^{\circ}C$. The initial pasting temperature by RVA increased after moisture-heat treatment. The peak viscosity of moisture-heat treated rice flour was higher for 30% moisture than that of the others. The rice flour treated with 30% MC and heated at $50^{\circ}C$ showed low setback and increased stability for retrogradation.

• Korean Journal of Food Science and Technology
• /
• v.45 no.5
• /
• pp.613-618
• /
• 2013

The quality characteristics of brown rice polished with grains of four rice varieties (Hwaseonchal, Baegjinju, Ilpum and Goami) were examined. For the physical properties of native and fried brown rice starches, the gelatinization temperatures and enthalpies (determined with differential scanning calorimetry) of brown rice starches decreased with increasing amylose content. The pasting viscosities of native brown rice starches in distilled water were higher than those in $HgCl_2$ solution (as an ${\alpha}$-amylase inhibitor). The highest viscosity of gelatinized starch was observed for the starch of Ilpum rice variety relative to other varieties. Cystal packing arrangement of brown rice starches subjected to deep-fat frying converted A-type (typically observed for cereal starches) into V-type (formed by retrogradation and recrystllization of amylose molecules).

• Journal of the Korean earth science society
• /
• v.24 no.1
• /
• pp.46-60
• /
• 2003

In Namyang Bay of western Korea, macrotidal-flat deposits are divisible into three late Quaternary units: Unit M1 of upper marine mud, Unit T1 of middle siderite-bearing terrestrial clay, and Unit M2 of lower marine mud. Unit M1 represents typical Holocene intertidal mudflat deposits, showing a coarsening-upward textural trend. It probably resulted from the continual retrogradation of tidal flat during the mid-to-late Holocene sea-level rise. Reddish brown-color Unit T1 consists of homogeneous clay with abundant freshwater siderite grains and plant remains. Unit T1 is clearly separated from the overlying Unit M1 by a sharp lithologic boundary. Radiocarbon age, siderite grains and lithologic features indicate that Unit T1 is originated from freshwater bog or swamp deposition infilling the localized topographic lows during the early Holocene age. Overlain unconformably by early Holocene swamp clay, Unit M2 is orange to yellow in color and mottled, suggesting significant degree of weathering during the sea-level lowstand. Such subaerial oxidation is confirmed in the vertical profiles of geotechnical properties, clay mineral assemblages and magnetic susceptibility. Unit M2 appears to be correlated with the upper part of the late Pleistocene tidal deposits developed along the western Korean coast. The sedimentary succession of the Namyang-Bay tidal-flat deposit provides stratigraphic information for the Holocene-late Pleistocene unconformity and also permits an assessment of the preservation potential of the late Pleistocene marginal marine deposit along the western coast of Korea.

• Journal of the East Asian Society of Dietary Life
• /
• v.23 no.5
• /
• pp.546-560
• /
• 2013

In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.

• Korean journal of food and cookery science
• /
• v.23 no.6
• /
• pp.961-967
• /
• 2007

The aim of this present study was to evaluate the effects of gamma-irradiation on the microbial and physicochemical characteristics of the rice flour porridge. The viscosity of the gamma-irradiated rice flour porridge was decreased as compared to that of the control. The soluble solid and reducing sugar content of the rice flour porridge was increased according to the gamma irradiation dose, while the blue value was decreased. From the results of a DSC curve, it was suggested that gamma irradiation delayed the retrogradation of the cooked rice flour porridge. The sensory score for overall acceptance and the chewing times for swallowing of the porridge, decreased with gamma irradiation doses above 3 kGy. Based on these results gamma irradiation may significantly enhance the swallowability of rice porridge, especially for elderly or infant subjects who have decreased mastication. However, more research is needed to improve the sensory qualities for the industrial application.