• Food Science and Biotechnology
• /
• v.18 no.4
• /
• pp.900-903
• /
• 2009

An oat gum was extracted from whole seeds of a drought harvested oat (Avena sativa). Oat gum presented a ${\beta}-glucan$ content of 65%(w/w) and an intrinsic viscosity of 141 mL/g. Gelling capability of oat gum at different concentrations was investigated. Gel hardness increased from 0.08 to 0.25 N as the oat gum concentration changed from 5 to 10%(w/v). Whippability, foam stability, emulsion stability, and reduced viscosity of oat gum at different pH were also investigated. Oat gum whippability was maximum at pH 7 (146%), while the higher foam and emulsion stability values were found at pH 9 (88 and 96%, respectively). The gum reduced viscosity increased from 715 to 958 mL/g as the pH changed from 7 to 9. Oat gum shows great potential as a gel forming, thickening, and stabilizing agent.

• Food Science and Biotechnology
• /
• v.16 no.5
• /
• pp.832-835
• /
• 2007

Moisture content of normal, waxy, and high amylose com starches was adjusted to 10-35%, and irradiated in a microwave oven. The effect of microwave irradiation on the crystalline structure of starch was measured by using a differential scanning calorimetry (DSC), and X-ray diffractometry. Pasting viscosity profile was also determined by using a rapid viscoanalyzer (RVA). For all the 3 types of starches tested, the rate of temperature increase by the microwave irradiation was faster and more rapidly reached the maximum temperature of the pressure bomb ($120^{\circ}C$) when the moisture content was higher. X-ray diffraction and DSC data revealed that the microwave irradiated starch underwent partial disruption of crystalline structure. RVA studies showed that the irradiation caused significant reductions in maximal viscosity and breakdown, whereas pasting temperature was increased. Overall trends revealed that the microwave irradiation on the starch containing limited moisture content (less than 35%) provided the effects similar to the heat moisture treatment. These effects became more significant when the moisture content was higher. Compared to waxy com starch, normal, and high amylose com starches appeared to be more susceptible to the microwave irradiation.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.1
• /
• pp.122-127
• /
• 2010

This study involved the making of sugar snap cookies with the addition of carrot powder at two to twelve percent which furnishes modern people with much lacking and needed dietary fiber. The review of the physiochemical properties, rheology and sensory evaluation of such contents resulted in the following findings: The sedimentation value and Pelshenke value all decreased in weak flour with the addition of more carrot powder, in comparison with the control group. The water retention capacity (WRC) and alkaline water retention capacity (AWRC) all increased in weak flour with the addition of more carrot powder in comparison with the control group. As for the gelatinization properties of the test samples measured by rapid visco-analysis, the addition of more carrot powder resulted in the initial pasting temperatures increasing in the case of weak flour, yet showing no significant difference between the control group and the carrot-added groups, as well as the maximum viscosity, minimum viscosity and final viscosity all showed the tendency of decreasing. The addition of more carrot powder led to the peak times in the mixographs for weak flour all exhibiting the tendency of decreasing, which might be interpreted as gradually weaker physical properties of the dough as well as less stability in the shape of the dough in turn.

• Journal of the Korean Society of Food Culture
• /
• v.33 no.3
• /
• pp.268-275
• /
• 2018

This study examined the effects of Boehmerianivea powder on the functional and sensory characteristics of dumpling shell. Various dumpling shell samples were prepared with wheat flour containing different amounts of Boehmerianivea powder. The instrumental characteristics were examined and sensory evaluations were performed. According to the amylograph data, the composite Boehmerianivea powder-wheat flour samples had increased gelatinization temperatures with increasing Boehmerianivea powder content; whereas the initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and the maximum viscosity were reduced. The L, a and b Hunter's color values decreased with increasing Boehmerianivea powder content. In addition to the cooked weight, the cooked volume and turbidity of dumpling shell increased with increasing level of Boehmerianivea powder. In terms of the textural characteristics, the addition of Boehmerianivea powder increased the chewiness, smoothness and adhesiveness. The DPPH free radical scavenging activity increased significantly with increasing content of Boehmerianivea powder (p<0.05). Finally, the results of the sensory properties indicated that 5% Boehmerianivea powder had the highest scores. These results suggest that Boehmerianivea powder can be applied to dumpling shells to achieve high quality and functionality.

• Korean journal of food and cookery science
• /
• v.14 no.3
• /
• pp.213-218
• /
• 1998

The changes in gelatinization patterns of potato were investigated while steeping in water for 7 days at 30${\pm}$1$^{\circ}C$. The transmittance of 0.1% starch suspension was increased rapidly from 60$^{\circ}C$ in raw starch and the starch steeped for 2 days, and increased rapidly from 65$^{\circ}C$ in the starch steeped for 4 and 6 days. As the steeping period increased, the transmittance was decreased at above condition. The gelatinization temperature of the starch measured by differential scanning calorimetry was increased from 62.79$^{\circ}C$ to 63.72$^{\circ}C$ as the steeping period increased. The gelatinization enthalpy reached the maximum in the starch steeped for 4 days. By amylograph, the initial gelatinization temperature was increased from 66$^{\circ}C$ to 84$^{\circ}C$ as the steeping period increased. Peak viscosity was decreased during steeping and the starch steeped for 5 days had no peak viscosity. Peak height after cooling to 50$^{\circ}C$ was increased up to the 4th day and began to decrease. As the steeping period increased, there was much loss of birefringence at higher temperature. The crystallinity by X-ray diffraction disappeared from 65$^{\circ}C$.

• Journal of ILASS-Korea
• /
• v.10 no.4
• /
• pp.8-15
• /
• 2005

The use of clean gaseous fuels for the purpose of high efficiency and low emission in automotive engines has tendency to increase in order to meet the reinforcing emission regulations and to efficiently utilize limited natural resources. Automotive companies developed and commercialized a LPG liquid injection system, which is mounted on LPLi(Liquid Phase LPG Injection) engines and vehicles based on this research trend. This research examines the biggest problem in LPLi engine, that is, the leakage characteristics of low viscosity LPG fuel according to the injector design variables. This study is also aimed to improve the performance of fuel-leakage in LPLi engine through the addition of a lubrication improver in HFRR(High Frequency Reciprocating Rig) facility. The needle displacement and the spring displacement of an LPLi injector are found to be already optimized. The possibility of a maximum of 70% leakage reduction compared to a conventional case, is verified when 1000ppm of a lubrication improvement material is added and 40% increase of a injector spring constant (K) is applied.

• Korean Journal of Food Science and Technology
• /
• v.19 no.5
• /
• pp.409-413
• /
• 1987

Microcrystalline collagen was manufactured from raw pigskins and its functional properties were measured. It showed a thixotropic behavior. The maximum viscosity was obtained at pH 3.5 and the viscosity increased with the increase of concentration in a nonlinear manner. The increase in temperature decreadsed the viscosity while the effect of temperature was greater at pH below 4.5. Foaming capacity was similar to that of gelatin but superior to that of egg white at 1%. The foam stability was inferior to that of egg white. Emulsifying capacity was lower than that of pork. Values from physical and chemical analysis were somewhat different from those of medical-grade microcrystalline collagen made from bovine cerium collagen.

• Journal of the Korean Society of Food Culture
• /
• v.29 no.4
• /
• pp.348-354
• /
• 2014

The purpose of this study was to investigate the effects of Curcuma aromatica powder on the functional and sensory characteristics of Mandupi. Various Mandupi samples were prepared with wheat flour along with addition of various amounts of Curcuma aromatica powder, after which instrumental characteristics and sensory evaluations were investigated. According to the amylograph data, the composite Curcuma aromatica powder-wheat flour samples showed increased gelatinization temperatures with increasing Curcuma aromatica powder content, whereas initial viscosity at $95^{\circ}C$, viscosity at $95^{\circ}C$ after 15 minutes, and maximum viscosity were reduced. In terms of Hunter's color values, L value decreased while a and b values increased with increasing Curcuma aromatica powder content. Besides cooked weight, cooked volume and turbidity of Mandupi increased as the addition level of Curcuma aromatica powder increased. In terms of textural characteristics, addition of Curcuma aromatica powder increased springiness, chewiness, and brittleness, whereas springiness and adhesiveness decreased. Based on sensory evaluations, the overall preference of Mandupi with 3% added Curcuma aromatica powder was higher than that of control.

• Journal of Microbiology and Biotechnology
• /
• v.3 no.4
• /
• pp.292-297
• /
• 1993

Aspergillus niger No. PFST-38 was grown on complex media in 30L agitated fermentors at various aeration rates and stirrer speeds. We could correlate the mixing time as a function of the Reynolds number and the apparent viscosity, as follows. ${\theta}_M=2.95\;\NRe^{-0.52},\;{\theta}_M=1.88\;{\eta_a}^{0.57}$ Also, the effects of the apparent viscosity (${\theta}_a$), the impeller rotational speed (N), the air flow rate ($V_s$), and the mixing time (${\theta}_M$) on the oxygen transfer coefficient, $K_L a$ were determined experimentally, and equated as follows. $K_La=12.04N^{0.88}Vs^{0.71}{n_a}^{-0.83},\;K_La=30.2N^{0.88}Vs^{0.71}{\theta_M}^{-1.45}$ $K_La$ increased as the agitation speed and the air flow rate increased. The rate of $K_La$ increase was dependent more on the rotational speed of impeller than on the air flow rate. The glucoamylase production increased with the increase of the agitation speed upto at 500 rpm and increased with the increase of air flow rate upto at 1.0 vvm. The values calculated from the above equation confirmed that the experimental maximum production of glucoamylase was achieved when the $K_La$ and the apparent viscosity of the broth were $260\;hr^{-1}$ and 1800 cps, respectively.

• Journal of the Korean Society of Food Culture
• /
• v.25 no.2
• /
• pp.225-231
• /
• 2010

The principal objective of this study was to evaluate quality characteristics of dried noodles when different concentrations of lotus leaf powder (LLP) were added to the wheat flour, thereby determining which noodle recipe was preferred. The cooking quality, mechanical texture properties, and viscosity were measured, and then a sensory evaluation was conducted with the prepared noodles. The gelatinization points of the composite LLP-wheat flours were shown to have an increased, viscosity at $95^{\circ}C$ after 15 minutes. As measured via amylograph, the maximum viscosity values of those samples were decreased as the LLP content was increased. As well, when increased amounts of LLP were added, both the L and a values were reduced, whereas the b value was increased. The color values, weight and volume of the cooked noodle increased, as did the turbidity of the soup. With regard to the textural characteristics, the LLP additive increased hardness and cohesiveness, and reduced adhesiveness and springiness. Overall, according to the results of our sensory evaluation, the noodles prepared with 5% LLP were preferred over the other noodles.