• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.696-701
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• 2011

To evaluate the processing adaptability of taro flours, the physicochemical properties of taro flour with different drying, roasting and steaming conditions were investigated. The moisture content and total dietary fiber were decreased as temperature increased with hot-air drying. Freeze-dried taro flours showed the highest vitamin C contents. Taro flours made by freeze-drying and hot-air drying showed significantly higher total dietary fiber content than those with roasting and steaming process. Steamed taro flours had the highest water absorption index, while hot-air dried and freeze dried taro flours had the highest water solubility index. No differences were displayed in the differential scanning calorimetry (DSC) thermal characteristics among hot-air dried and freeze dried taro flours. Roasted taro displayed decreased onset temperature and peak temperature as roasting temperature increased. Using a rapid visco-analyzer, the peak viscosity, through viscosity, and final viscosity of dried and steamed taro flours were higher than roasted taro flours, whereas the set back value, which is a prediction of retrogradation, decreased with steaming processing. From those results, it could be concluded that hotair dried taro flours, which have high gelatinization viscosity, are beneficial in imparting viscosity to dough products and hot-air drying after steaming taro flours, which retard retrogradation, is good for porridge and flake base products.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.401-406
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• 2011

This study was conducted to investigate the pasting and sensory properties of different commercial rice cultivars. All samples had adequate moisture content, and Gyeonggi Kosihikari had the lowest protein content (6.75%). Apparent quality of head rice ranged from 85.63 to 98.70% and amylose content was 21.51-26.54%. In a rapid visco analyzer examination, pasting temperature of Gyeonggi Kosihikari was the lowest (84.87). Breakdown of Gangwon Oade (43.64 RVU) was lower that of others, indicating the highest pasting stability. The setback of Jeonam Hitomebore was the lowest (81.56 RVU), suggesting slow deterioration. A texture analysis test showed that Gyeonggi Koshihikari had the lowest hardness and Chungnam Samgwang had the highest adhesiveness. Gyeonggi Koshihikari had the highest sensory scores for appearance, flavor, taste, texture and overall acceptability. These results indicate that Gyeonggi Koshihikari is the most adequate rice product among cultivars.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.391-398
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• 2001

This study was carried out to investigate the effects of storage temperature(5$\^{C}$ and 25$\^{C}$) and time(1, 24, 48 and 72hours) on the retrogradation characteristics of mungbean starch gels by using differential scanning calorimeter, rapid visco-analyzer, $\beta$-amylase method, X-ray diffractometer and scanning electron microscope. Endothermic peaks of gels stored at 5$\^{C}$ were shifted to the lower temperature than those stored at 25$\^{C}$ and endothermic enthalpy of gels stored at 5$\^{C}$ was greater than that stored at 25$\^{C}$. DSC thermograms showed that the retrogradation rate of gels stored at 5$\^{C}$ was higher than that shored at 25$\^{C}$. The pasting properties of the gels such as peak viscosity and final viscosity increased with increasing storage time except the gels stored at 25$\^{C}$ for 72 hours and this trend was more apparent at the storage temperature of 5$\^{C}$. The digestibility measured by $\beta$-amylase method decreased with increasing storage time and this trend was more apparent at the storage temperature of 5$\^{C}$. X-ray diffraction patterns of the gels stored at 5$\^{C}$ showed more distinct peak than those stored at 25$\^{C}$, but no difference was detected by the storage time. The microstucture of all the gels showed a well developed three dimensional network The network structure of the gels stored at 25$\^{C}$ formed a thick matrix after 72 hours and those stored at 5$\^{C}$ from the early stage of storage.

• Korean journal of food and cookery science
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• v.30 no.3
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• pp.271-277
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• 2014

The purpose of this study was to investigate Tteokbokki tteok that has properties of five different rice cultivars (Haiami, Samkwang, Goami, Saegyejinmi and, Seolgaeng). The moisture and crude protein contents of rice were 14.13-17.78% and 4.43-7.68%, respectively. The crude lipid and crude ash of rice were 0.45-1.84% and 0.37-0.85%, respectively. The water binding capacity of Goami cultivar was higher than that of other rice flours. Asa the soaking time increased, water absorption was the highest in the Goami cultivar (45.30%). Using a rapid visco analyzer (RVA), the initial pasting temperature of Goami cultivar was the highest; further, the peak viscosities of Samkwang cultivar and Saegyejinmi cultivar were higher than of those of other rice flours. The hardness of the Tteokbokki tteok was the highest the in the Goami cultivar (7,293.08 g); conversely, the Saegyejinmi cultivar had the lowest value (2,502.08 g). In the sensory evaluation of Tteokbokki tteok, the color, texture, and overall acceptability were the highest in the Saegyejinmi cultivar, the appearance was highest in the Samkwang cultivar, and the flavor was the highest in the Seolgaeng cultivar. Lastly, the Goami cultivar yielded the lowest values in the sensory evaluation, except for appearance and color.

• Journal of the Korean Society of Food Culture
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• v.28 no.6
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• pp.664-673
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• 2013

This study was conducted to investigate the physicochemical properties of mung bean starch and the quality characteristics of mung bean starch gels supplemented with gelatin and isolated soy protein (0, 2, 5%) during storage at $5^{\circ}C$ for 0, 24, 48, and 72 hours. The swelling power of mung bean starch supplemented with gelatin did not significantly change, whereas those supplemented with isolated soy protein (ISP) significantly increased. The solubility of mung bean starch supplemented with gelatin and ISP, however, significantly increased with increasing concentration. In addition, the soluble amylose and soluble carbohydrate of mung bean starch supplemented with gelatin and ISP significantly decreased with increasing concentration. In terms of pasting properties measured by the Rapid Visco Analyzer (RVA), the pasting temperature of mung bean starch supplemented with gelatin and ISP was not significantly different, whereas peak viscosity, minimum viscosity, final viscosity, breakdown, and consistency decreased. DSC thermograms showed that the onset temperature of mung bean starch supplemented with gelatin and ISP did not significantly change, whereas the enthalpy increased with the addition of 5% ISP. The lightness (L) and redness (a) of mung bean starch gels supplemented with gelatin, ISP, and without additives increased during cold storage, whereas the yellowness (b) decreased. The addition of gelatin and ISP suppressed changes in L, a and b of mung bean starch gel during cold storage. Synereses of mung bean starch gel supplemented with gelatin and ISP was lower than that without additives, with the addition of gelatin suppressing synereses more than ISP. The addition of gelatin and ISP also suppressed increases in hardness, chewiness, and gumminess of mung bean starch gels during cold storage. In the sensory evaluation, the addition of gelatin and ISP suppressed increases in hardness and brittleness of mung bean starch gels during cold storage. The addition of 2%, 5% gelatin and 2% ISP also suppressed a decrease in the overall acceptability of mung bean starch gels during 24-48 hr cold storage. Thus, the addition of 2-5% gelatin and 2% ISP to mung bean starch is appropriate for suppressing the quality deterioration of 24-48 hr cold-stored mung bean starch gels.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.495-500
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• 2006

The physicochemical properties of brown rice flours produced under different drying and milling conditions were investigated. Moisture contents of hot-air dried, microwave dried and zet-milled brown rice flours (BrWZH) were 10.7%,13.7% and 8.0%-8.6%, respectively. Water absorption indices (WAI) and water soluble indices (WSI) of roll-milled brown rice flours (BrWRH) were lower (0.40-0.59 g/g; 0.7-3.0%) than those of zet-milled brown rice flours (0.58-0.79 g/g; 4.0-7.3%). Zet-milled brown rice flours had higher Hunter L values and more damaged starch (94.1-96.8; 28.2%) compared to roll-milled brown rice flours (91.3-91.9: 15.5%). The percentage of damaged starch and L values of brown rice flours increased as particle size of brown rice flours decreased. Roll-milled polished rice flour (Control) had the highest L value and lowest amount of damaged starch (97.1; 8.2%). Control, BrWRH, BrWZH, and ultrafine brown rice flour (HBrZMU) had peak viscosity values of 321, 255, 221, and 162 RVU, respectively and trough viscosity values of 217, 185, 175, and 113 RVU, respectively. Peak and trough viscosity (Rapid Visco Analyzer; RVA) properties of rice floors decreased as the particle size of rice flours decreased. HBrZMU demonstrated a higher onset temperature $(61.1^{\circ}C)$ compared to control $(54.8^{\circ}C)$ by differential scanning calorimetric (DSC). Crystal melting enthalpy $({\Delta}H)$ of control and brown rice flours were 10.4 J/g and 6.1-8.7 J/g, respectively. Results of this study suggested that physicochemical properties of brown rice flours were closely related to their particle size.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.304-310
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• 2017

The aim of this study was to compare the physicochemical properties of domestic and imported commercial plain wheat flour and dough. Four types of domestic wheat flour (DW; DW1-4) were compared to four types of imported wheat flour (IW; IW1-4). DWs exhibited lower moisture content, lightness (L), and whiteness, and higher protein content, redness (a), and yellowness (b), than those exhibited by IWs. Solvent retention capacity of DWs and IWs was similar; however, DWs showed higher gluten performance index. Pasting properties, analyzed by rapid visco analyzer (RVA), were similar for DW1, DW2, and IWs; however, DW3 and DW4 showed different RVA patterns. Considering that DW3 and DW4 were organic wheat flour, possible incorporation of damaged kernel might increase amylase activities resulting in decreased peak viscosity. Dough resistance (108.4-159.9 g) and extensibility (11.8-16.7 mm) of IWs were higher than those of DWs (78.0-118.7 g, 8.7-12.5 mm, respectively).

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.618-627
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• 2016

This study evaluated the hydration, gelatinization, and saccharification properties of rice processing for beverage development. The properties of rice were studied on 10 rice cultivars (Samkwang, Ilpum, Seolgaeng, Anda, Dasan-1, Goami-4, Danmi, American rice, Chinese rice, and Thai rice) and employing four kinds of pre-treatment methods (dry grain, wet grain, dry flour, and wet flour). The results showed that moisture content of rice was between 11.88~15.26%. Increase in soaking time along with highest water absorption was noted in American rice cultivar (46.81%). The water binding capacity of Thai rice was higher when compared to that of other rice flours. In addition, solubility and swelling power of rice were 4.52~26.65% and 0.19~2.05%, respectively. The amylose content of Goami-4 was higher in rice processing. Using a rapid visco analyzer (RVA), the initial pasting temperature of Danmi cultivar was found to be the highest; the peak viscosities of Anda cultivar and Dasan-1 cultivar, and Chinese rice were higher than of those of other rice flours. After saccharification, the pH, soluble solids content, and reducing sugar content of rice processed through different pre-treatment methods were in the range of 6.22~7.08, $4.67{\sim}16.07^{\circ}Brix$, and 0.35~11.67% (w/w), respectively. In terms of color values, the L-value of dry grain, a-value of wet (grain, flour), and b-value of dry sample (grain, flour) were found to be the highest. Assessment of various factors and cultivars characteristics of the raw grains are of importance in the development of rice beverage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.172-183
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• 2017

Germinated brown rice (GBR) has received considerable attention over the last decade as a means of enhancing the nutritional value and health-promoting functions of rice. The effect of germination on the physicochemical and textural properties of brown rice (BR) was investigated in different rice varieties (Samkwang, Misomi, Chindeul, and Hyeonpum). Cooking properties, such as water absorption, expanded volume, and soluble solids were significantly increased by germination in all rice varieties. Textural properties (hardness, toughness, adhesiveness, and stickiness) of cooked samples were determined using a texture analyzer. Hardness and toughness were decreased by germination, whereas stickiness and adhesiveness increased significantly. These results revealed that germination leads to improvements in the cooking and eating properties of BR. In Rapid Visco Analyzer (RVA), significant reductions were observed for peak viscosity, break down, set back, and final viscosity after germination. Although the amylose content of Misomi was slightly decreased by germination, that of other varieties increased significantly. Germination induced no noticeable change in the average chain length of amylopectin in Misomi, Chindeul and Hyeonpum, but led to a significant increase in Samkwang.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.613-619
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• 2010

Three varieties of taro flours (Altoran, Josaengjong, and Jaeraejong) were analyzed to evaluate their nutrient composition and physicochemical properties. Moisture contents of the three taro cultivars varied from 5.74-10.30%. Among the three cultivars, Altoran flour had higher protein and fat contents than other cultivars. There were 17 kinds of amino acids in the three taro flours. The major fatty acids in the three taro flours were linoleic acid (46.5-51.4%), palmitic acid (21.7-25.8%), and oleic acid (12.3-18.7%), and two thirds of the total fatty acids were unsaturated fatty acids. Potassium, phosphorus, magnesium, and calcium were the most plentiful minerals in the three taro flours, and the free sugars were glucose, fructose, and sucrose. The total dietary fiber contents of the three taro flours ranged from 12.97 to 17.60%. From these results, Altoran contained a high level of dietary fiber, minerals, essential amino acids, and free sugars. Jaeraejong showed the highest water absorption index. The water soluble index of Altoran was higher than that of the other cultivars. From the differential scanning calorimeter results, the gelatinization temperatures of the three taro flours were $84.98-89.91^{\circ}C$. The pasting temperature of the three taro flours was from 46.77 to $49.30^{\circ}C$ by rapid visco-analyzer. Among these varieties, Josaengjong had the highest peak viscosity and final viscosity, whereas Altoran had the lowest. These taro cultivars are expected to be potential material for application in taro processed foods, due to their gelatination and pasting properties.