• Food Engineering Progress
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• v.14 no.2
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• pp.135-145
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• 2010

In order to enhance overall quality of the Backsulki, a sweet potato flour (SPF) which is rich in sugar and dietary fiber was added into the rice flour at 0, 5, 15, and 25% (w/w, db) ratios. Quality changes of the products were evaluated by storing at 5, 15, and 25$^{\circ}C$ for 4 days. Water binding capacity, swelling power, and solubility of the products increased as the SPF increased. Hunter colorimetric a- and b-value increased while L value of the products decreased as the SPF increased. Retarded retrogradation of the flour mixtures containing the SPF was shown from the DSC thermogram as indicated by the decreased $\Delta$H values. Increases in $T_{i}$ and $T_{p}$ values in relation with the starch gelatinization were shown from the DSC thermogram with a temperature margin of 15-20$^{\circ}C$ as the SPF increased. Increases in softness along with decreases in springiness and chewiness of the products were shown as the SPF increased. It was not so much the storage temperature as the added SPF affected the final texture of the products. Retarded growth of the total microbes of the products was noted by the added SPF during storage at 25$^{\circ}C$ for 3 days. Regarding the above and additional sensory preference scores of the products, a 15%(w/w) level of the SPF was suggested as optimum for the best Backsulki with improved qualities.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.69-76
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• 2009

This study was conducted to determine the optimal cooking conditions for brown rice using an electric pressure rice cooker. The effects of steeping conditions and cooking pressure on the hydration, gelatinization, texture and palatable properties of cooked brown rice were evaluated. Based on water uptake and DSC data, the optimal steeping time and temperature for brown rice were determined to be 25 minutes and ${\sim}60^{\circ}C$, respectively. The cooking conditions for brown rice were then divided into the following 6 categories: steeping at $25^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (25P) or 1.9 (25HP), steeping at $57^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (57P) or 1.9 (57HP), steeping at $85^{\circ}C$ for 15 minutes and cooking at an atmospheric pressure of 1.7 (85P) or 1.9 (85HP). The susceptibility of cooked brown rice starch to degradation into maltose by ${\alpha}$-amylase, which is related to the degree of gelatinization and in vitro digestibility, were then determined. The amount of maltose produced by cooked brown rice samples was highest in the 57HP group, followed by the 57P and 85HP groups. Storing cooked brown rice at $73^{\circ}C$ for 24 hours resulted in significantly higher amounts of starch being degraded into maltose in the 57P, 57HP and 85HP groups than in the other groups. Textural analysis demonstrated that the 57P, 57HP and 85HP groups had significantly lower gumminess and chewiness values when compared to the other groups, and that 57HP received had the lowest hardness of all treatments. These results were confirmed by the results of the sensory evaluations. Furthermore, the 57P and 57HP groups were found to have a higher glossiness, stickiness aroma and taste score than the other groups. These findings were taken to indicate that steeping conditions and pressure exerted a positive synergistic effect on the cooking quality of brown rice. The texture analyzer also revealed that storing the cooked rice at $73^{\circ}C$ for 24 hours only led to significantly lower scores in gumminess, hardness and chewiness in the 57P and 57HP groups, which indicates that these groups underwent a lesser degree of retrogradation than other groups. Taken together, the results of the present study demonstrate that steeping brown rice at $57^{\circ}C$ for 25 minutes and a higher cooking pressure improved the palatability and in vitro digestibility of brown rice significantly.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.10
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• pp.1460-1468
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• 2011

This study investigated the quality changes and characteristics (0, 3, 6, 9%) of pound cake made with flour that included gamma irradiated (50 kGy) hot water extracts of Undaria pinnatifida sporophyll (WEUS). The pH of pound cakes decreased with increasing powder concentration, and gamma-irradiated pound cakes had lower pH than non-irradiated pound cakes at the same powder concentrations. The height, volume, specific loaf volume, and baking loss showed no significant differences between control and experimental groups. With increasing powder concentration, the L value of the crust and crumbs decreased, but the a value increased. The b value showed different tendencies between crust and crumb. The crust value was reduced with higher content of WEUS, but the crumb value increased. Gamma-irradiated pound cakes were also less hard than non-irradiated pound cakes. On the other hand, adhesiveness and springiness decreased with increasing powder concentration, but were not significantly different from the control. Also, gumminess and chewiness decreased but not significantly so. The hardness after several days of storage (5, 10, and 15 days) was higher than the control, and the springiness and cohesiveness were significantly reduced with increasing concentration compared to the control. The retrogradation increased in the control group, but it did not in the experimental groups. Results of radical scavenging activity using DPPH indicated that the gamma-irradiated group was higher than the non-irradiated group and it was also higher with higher concentrations of powder. In a sensory evaluation, when compared to the control, pound cake with 3% WEUS was superior in taste, flavor, and overall preference. Therefore, it was found that pound cake with 3% WEUS powder with gamma irradiation of 50 kGy added could improve the yield, taste, and antioxidant activity of pound cake.

• Korean journal of food and cookery science
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• v.26 no.2
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• pp.198-205
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• 2010

In this study, the effect of added cashew nuts on the quality characteristics of pound cake were investigated. The weight and volume of the cake increased with the addition of cashew nuts concentration, whereas the dough yield and baking loss decreased. Furthermore, the hardness, penetration and, degree of retrogradation significantly decreased during storage with the addition of cashew nuts. As the cashew concentration was increased, the lightness and redness values of the crumb decreased and the yellowness values increased. In terms of sensory evaluation, when compared to the control group, the cashew nuts pound cake was superior in taste, flavor, chewiness and overall acceptability.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.461-468
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• 2007

The quality characteristics of bread made from domestic Korean wheat flour that contained different amounts of cactus Chounnyuncho (Opuntia humifusa) powder were investigated. The water absorption and peak time, as determined by a farinograph, increased with increasing amounts of cactus powder, while stability, elasticity, and weakness decreased (p<0.05). RVA(Rapid Visco Analyzer) analysis showed that wheat flour retrogradation was retarded by increasing cactus powder content (p<0.05). The fermentation time of the bread increased with increasing cactus powder content, while the fermented volume and baking loss decreased (p<0.05). According to the sensory test, the most preferred bread contained 3% cactus powder (p0.05).

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.387-395
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• 2009

This study was conducted to investigate the effects of starch concentrations and heating conditions on the gel characteristics of arrowroot starch. Arrowroot starch gels with various pHs, and starch concentrations, were prepared using different temperatures and heating times, and then stored for 24 hrs at $4^{\circ}C$. The hardness of sample gels made at pH 2.0 and 4.0 increased as the starch concentration increased from 7% to 10%, with the maximum value of 94 N being obtained when the gel was prepared at pH 4.0 with a starch concentration of 10%. The maximum hardness of samples prepared with concentrations of starch ranging from 7~9% appeared at $80^{\circ}C$, regardless of the heating temperature and time. Furthermore, the hardness of samples prepared at greater than $100^{\circ}C$ was relatively lower than that of samples prepared at other temperatures. When a starch concentration of 8% was used, the degree of gelatinization(DR) increased as the heating temperature increased, with the maximum value of DR being about 76% at $120^{\circ}C$, regardless of heating time. After storage for 24 hrs, the hardness of samples prepared at $70^{\circ}C$, $80^{\circ}C$ and $90^{\circ}C$ appeared to decrease, while that of samples prepared at $100^{\circ}C$, $110^{\circ}C$ and $120^{\circ}C$ increased. The correlation between hardness and the degree of gelatinization or retrogradation was very high when samples were prepared at $80^{\circ}C$ with a starch concentration of 9%, as indicated by a correlation coefficient of greater than 0.95. Overall, the microstructures of freeze-dried arrowroot starch gel were composed of a continuous network of amylose and amylopectin with fragmented ghost structures in an excluded phase, but these ghost structures were more evident after storage and with increased heating temperature.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1022-1031
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• 2008

Pound cakes were prepared with Citrus mandarin powder(CMP) cultivated in JeJu Island, Korea. The impact of CMP amount level, which was incorporated into wheat flour by the ration of 0, 5, 10, 15, and 20% based on a flour weight, on the rheology and sensory profile of the pound cakes was measured. Moisture content of 13.70%, crude protein 5.12%, crude lipid 1.30%, crud ash 1.92%, respectively. Also evaluation was performed on the changes in physicochemical properties of the pound cakes during storage at 4 and $30^{\circ}C$. According to the amylogram, gelatinization temperature of the control dough was $63.35^{\circ}C$ and those of the dough with CMP were $63.85{\sim}66.55^{\circ}C$. Maximum viscosity of the dough was 686 B.U in the control, those were 575 B.U, 553 B.U, 504 B.U and 401 B.U in the dough with 5, 10, 15, and 20% CMP, respectively. The retrogradation degree(setback value) of CMP dough was $31{\sim}57%$ lower than that of the control dough under the same conditions. Water holding capacity of pound cake was increased gradually in proportion to the amount of CMP. The CMP addition decreased the brightuess(L) of pound cakes but increased redness(a) and yellowness(b). Hardness of pound cakes was significantly increased by CMP addition, while springiness, adhesiveness and cohesiveness were decreased. Based on sensory evaluation, pound cakes added with CMP were not significantly different in color and texture, while that of 10% CMP was significantly high in taste, flavor, and overall preferences, compared to the control. pH of pound cake with CMP was decreased during storage, showing that pH of CMP samples was lower than the control. Titrated acidity of pound cake with CMP was increased rapidly from storage for 10 days, which the changes in degree was fast in accordance with CMP amount. The Hunter's color value of pound cake with CMP was decreased, as the storage time proceeded. In the samples prepared with CMP, the firmness, adhesiveness, gumminess and chewiness was increased as the storage time proceeded, while springiness and cohesiveness was decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.613-621
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• 2006

This study was performed to evaluate the storage quality of milk bread added with $\beta$-glucan (10 20 and 30%), which is a functional food material produced from Agrobacterium spp. R259 KCTC 10197BP. During storage ($20^{\circ}C$, 40% relative humidity) the pH of all breads gradually increased, although there were no significant differences in pH of the $\beta$-glucan added milk bread from those of the control. During storage, the moisture content of all groups decreased, however, moisture contents in the $\beta$-glucan added breads were higher than that in the control. Hunter color values ($L^*,\;a^*\;and\;b^*\;value$) of the milk bread added upto 20% $\beta$-glucan were not significantly different, but the lightness increased during storage. Rapid increase of hardness in the milk bread during storage was observed in control, while the hardness of $\beta$-glucan added bread increased slowly. Also, the degree of retrogradation of bread decreased as $\beta$-glucan addition amount increased. Sensory evaluation showed that the score of over-all acceptability of the bread added with 20% $\beta$-glucan was the highest among treated groups until four days of storage. This study confirmed that the addition of $\beta$-glucan to milk bread maintained the moisture content and delayed hardness during storage.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.144-152
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• 1977

The physiochemical properties of eight different cultivars or newly bred lines of glutionous rice were investigated and obtained following results; (1) The gelatinizing temperature, blue value and alkali number of starch separated from the sample cultivars or lines were similar to those of starch from conventional cultivar Olchal. The expansive power of three newly bred lines were somewhat weaker than that of starch from conventional cultivar, but the expansive power of other four lines were similar to that of conventional cultivar. (2) pH of cooked rice of the ten sample cultivars or breeding lines showed no discernible differences rangeing from 6.54 to 6.60. (3) The degree of gelatinization of cooked rice of newly bred lines were rather lower than that of conventional ones, but the degree of their retrogradation were somewhat higher than that of conventional cultivars. (4) In order to improve the palatability of cooked rice of Tongil (common rice), glutinous rice were mixed in different rate. The results showed that a mix ratio of six per cent glutinous rice was most favourable. The acceptability of common Tongil rice was improved when it was cooked with four to six per cent of glutinous rice mixed, and it showed no significant difference from that of Akibare alone cooked rice. Also no difference was noticed among newly bred glutinous lines in the acceptability when they cooked with common Tongil rice mixed. (5) Injolmi, Yaksik, Misitgaru, Twipap and Yugwa were prepared from glutinous rice of sample cultivars and or breeding lines to study their characteristics in processing and their acceptability. The results indicated that the acceptability score of newly bred lines were lower than that of conventional cultivar in cases of Twipap and Yugwa, but in cases of Injolmi, Yaksik and Misitgaru, identical score was obtained from both of newly bred lines and conventional cultivars.

• Food Engineering Progress
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• v.15 no.1
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• pp.56-63
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• 2011

Durum wheat semolina was added into wet-milled rice flour in order to improve chewy texture, firm bite ("al dente"), and resistance to overcooking of the ordinary rice noodles. Wet noodles were prepared by mixing 0 (control), 5, 10, 15, and 20% (w/w) of semolina per semolina and rice flour mixtures. Vital gluten (4%, w/w) and salt (2%, w/w) were added to form the pliable strands of wet noodles and final moisture contents of the raw mixtures were equalized at 45%. Pasting properties of the suspended flour mixtures as measured by the Rapid Visco Analyser (RVA) showed slight increases (up to $1.2^{\circ}C)$ in pasting temperatures along with the considerable decreases in peak viscosities as semolina increased at over 15%. Reduced shear thinning and retrogradation of the starch solution that leads to hardening of the cooked noodles were indicated by lowered breakdown viscosities and gaps between finaland setback viscosities from the RVA viscogram as semolina increased at over 10%. Reduced water uptake and turbidity increases of the cooking water as caused by the soluble starches from the noodle were also noted as the content of semolina increased. More or less significant (p<0.05) decreases in colorimetric L (lightness) value of the raw- and cooked noodles were observed as semolina increased while a- (redness) and b (yellowness) values were rather increased at the same moment. Textural properties of the cooked noodles such as hardness, springiness, cohesiveness, gumminess, and chewiness from TPA tests were significantly (p<0.05) influenced by added semolina, even at 5%-levels or more. It can be concluded that addition of semolina into rice flour could provide easy handling of the wet noodles without distortion during transportation, integrity and firm bite of the cooked noodles, and less loss of starch to the cooking water in comparison with the ordinary rice noodle. It was finally suggested that optimum level of the semolina in the product was approximately 10% for the quality wet rice noodle products.