• Journal of the East Asian Society of Dietary Life
• /
• v.5 no.3
• /
• pp.255-262
• /
• 1995

Studies were carried out to investigate physicochemical properties of taro during the pretreatment process of making Toranbyung. Seventeen kinds of amino acids were found in taro. Aspartic acid and glutamic acid were most plentiful among those amino acids. Essential amino acids were about 42.7% of the total amino acids. Sulfur containing amino acids, mehtionine and cystine were about 2.7% The amylograph indicated that the initial temperature triggering gelatinization of both rice flour mixed with taro and glutinous rice flour mixed with taro increased as the amount of taro increased. But the maximum viscosity of rice flour mixed with taro did not increase as the amount of taroincreased while the maximum viscosity of glutinous rice flour mixed with taro increased as the amount of taro increased. And the peak temperature of both rice flour mixed with taro and glutinous rice flour miced with taro increased as the amount of taro increased. The alkali degree of insoluble ash was higher than that of soluble ash. Glutinous rice dough had more total sugar than rice dough. Yellowness of rice dough was higher than that of glutinous rice dough.

• Korean journal of food and cookery science
• /
• v.22 no.5 s.95
• /
• pp.712-719
• /
• 2006

Sugar cookies using various levels of citron powder were prepared and the physicochemical and sensory characteristics were investigated in this study. The pH of the dough was relatively lower in the groups with increased citron powder. The yellowness of dough color was significantly increased from value of 23.47 to 36.99 as the substitution levels of citron powder content was increased (p<0.05). The degree of gelatinization of the dough measured using DSC was reduced with increasing delayed with the increased amount of the powder content. Cookies with powders content of 4-6 g showed significantly lower water contents than compared to those with 0-2 g(p<0.05). The spread factor tended to decrease as the substitution levels of the sample groups were increased. The results of sensory characteristics showed significantly higher bitterness and lower sweetness with the 6 g substituted sample group at (p<0.05). Desired citron cookie was prepared with the group of a substitution levels of 4 g citron powder from the confounded viewpoint of the physicochemical and sensory properties that were investigated.

• Korean journal of food and cookery science
• /
• v.8 no.3
• /
• pp.281-289
• /
• 1992

The physicochemical, rheological and sensory characteristics of Backsulgies added with dietary fibers-cellulose, pectin and wheat bran-were investigated. The maximum acceptable ratio of fibers was 10% for wheat bran or cellulose, 3% for pectin. As me results of physicochemical analysis, cellulose and pectin had larger water-binding capacity man wheat bran. Swelling power was increased with temperature increment. But the type of added dietary fiber did not make significant differences. The degree of gelatinization was measured by maltose content. The retrogradation of backsulgies was significantly delayed by the addition of dietary fibers. The retardation effect of dietary fibers for retrogradation of backsulgies was also proved by textural analysis and time constant determination of Avrami equation. Pectin had especially excellent delaying effect while me storage time extended. There were no significant differences in sensory characteristics between me backsulgi with no dietary fibers and backsulgies added with cellulose 3%, pectin 1% and wheat bran 3%. Therefore, we concluded mat cellulose 3%, pectin 1% and wheat bran 3% were me optimum addition ratios, which have the delaying effect of retrogradation, and which could be accepted as same as conventional backsulgies organoreptically.

• Korean journal of food and cookery science
• /
• v.17 no.5
• /
• pp.431-440
• /
• 2001

This study was carried out to investigate the effects of oligosaccharide addition on Jeung-Pyun fermentation. Fructooligosaccharide (FOS), isomaltooligosaccharide (IMOS), galactooligosaccharide (GOS) were used at the concentration of 15%, 25% or 35% of the rice in Jeung-Pyun ingredients. The physicochemical properties, sensory evaluation and instrumental characteristics were examined. The internal structure of Jeung-Pyun samples was observed by SEM. The pH of Jeung-Pyun batters was decreased as the fermentation progressed. Compared with the control using sucrose, the specific volume of Jeung-Pyun was higher in the 15% and 25% of oligosaccharide-added samples. The degree of gelatinization decreased more slowly than control as the storage time increased both at 20$\^{C}$ and 4$\^{C}$. In sensory evaluation, Jeung-Pyun with FOS and IMOS at the levels of 25∼35% and GOS at the levels of 25% showed the best scores. In instrumental characteristics, springiness, gumminess, hardness and cohesiveness were similar among all samples during storage at 20$\^{C}$ and 4$\^{C}$. In the internal structure of Jeung-Pyun observed by SEM, Jeung-Pyun substituted with oligosaccharide at the levels of 25% for sucrose showed large and regularly distributed air pores. In conclusion, the replacement of sucrose with oligosaccharide in Jeung-Pyun ingredients appeared acceptable in terms of fermentative aspects.

• Journal of the East Asian Society of Dietary Life
• /
• v.7 no.1
• /
• pp.47-55
• /
• 1997

This study aims to know what the physicochemical properties and physical properties of the Korean traditional rice cake injulmi made from persimmon powder and glutinous rice(powder), and to come up with a standard recipe of it with the premixed powder of persimmon and glutinous rice. Cooked rice powder with 9 different levels of persimmon in cooling dough(75, 100 and 150${\mu}{\textrm}{m}$ power with each 20, 40, and 60%) was tested for rheological parameters, the rate of swelling, degree of gelatinization, sensory evaluation, and the observation of cross section used to electronmicroscope. 1. sensory evaluation conducted by 20 university students as panelists showed that mixed glutinous rice powder and persimmon powder lost their regular forms. increase in persimmon powder content increased a thin layer of starch granule, presumably due to sugar and fiber in the mixed persimmon powder granule. 3. In cooking the rice cake with 20~60% of persimmon, it showed 6.3 to 5.5 pH. 4. Quantitative description analysis conducted by 20 university student s panelists showed that sample that sample C was preferred among 9 samples. From these results, it was concluded that glutinous rice cake cooked with 20% of persimmon powder was quiet acceptable. Optimum cooking condition for the glutinous rice with persimmon powder rice cake was 30min of cooking time and 25$0^{\circ}C$ of cooking temperature with gas oven.

• The Korean Journal of Food And Nutrition
• /
• v.6 no.3
• /
• pp.178-188
• /
• 1993

This research was attempted to investigate changes in physicochemical properties of rice extrudate with added ginger powder extruded by single screw extruder. Graphic three dimensional analysis on response surface regression was used to evaluate effects of extrusion variables on quality factors of the extrudate according to two independent variables, ginger consent 0∼12%, moisture content 14∼26%. The summarized results are as follows : 1) Regarding proximate composition of rice extrudate with added ginger powder, as ginger powder content of raw material Increased, crude tat, crude protein, crude ash and crude fiber increased, while soluble nitrogen free extract decreased. 2) Graphic three dimensional analysis on response surface regression was conducted for each dependent variable which revealed statistically significant relationship with independent variables, 0∼120A ginger and 14∼26% moisture content. Expansion ratio had a critical point as moisture content changed. As ginger and moisture content Increased, bulk density, break strength and water absorption Index Increased, while water solubility Index decreased. The predicted maximum degree of gelatinization in 6.15% ginger and 15.56% moisture content is 88.27%, and lightness decreased as ginger content Increased. According to the microstructure for the cross section of extrudate obsorbed with image analyzer, air cell number and perimeter revealed saddle point, meanwhile total area and fractarea of air cell had critical points as moisture content changed. In view of the results, quality of rice extrudate with added ginger powder was optimum when rice flour was fed to the extruder with 2∼7% singer powder and 15∼20% moisture content.

• Journal of the East Asian Society of Dietary Life
• /
• v.12 no.6
• /
• pp.574-579
• /
• 2002

The effect of Woomegi Dduct mixed with Tack-ioo and So-ju, and made of glutinous rice flour added with various proportions of nonwaxy rice and wheat flour, were studied by the textural and the sensory characteristics. Springiness, gumminess of Woomegi Dduck added with wheat flour tended to be higher than the one with nonwaxy rice flour and cohesiveness tended to increase as the addition amount of glutinous rice flour increased. The degree of gelatinization tended to decrease as the addition of nonwaxy rice flour and wheat flour contents increased from 10 to 50% Overall sensory score of the sample with 50% of wheat flour added to the glutinous rice flour and mixed with Tack-joo was the highest.

• Journal of Applied Biological Chemistry
• /
• v.50 no.4
• /
• pp.234-238
• /
• 2007

The effects of ultra-fine pulverization on the physicochemical properties of rice starch (RS) were investigated using a high impact planetary mill. After pulverization, RVA characteristics, peak viscosity, break down, and set back values of RS decreased from 274.75 to 9.42 RVU, 214.46 to 6.17 RVU, and 87.80 to 17.00 RVU, respectively. The pasting properties also changed significantly. X-Ray diffractogram revealed RS had four A-type peaks, which disappeared after pulverization. The peak temperature and gelatinization enthalpy of RS using differential scanning calorimetry (DSC) were 13.99 J/g at $75.14^{\circ}C$, whereas the pulverized RS (PRS) had two peaks, 0.13 J/g at $63.88^{\circ}C$ and 1.23 J/g at $101.24^{\circ}C$. DSC measurement showed the retrogradation degree of PRS was lower than that of RS after storage at 4 and $25^{\circ}C$. The enzymatic (${\alpha}$-amylase) digestibilities of RS and PRS were 72.7 and 77.3%, respectively.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.4
• /
• pp.304-311
• /
• 2019

Ohmic heating is a heating method based on the principle when an electrical current passes through food. Since this method is internal, electrical current damage occurred during heating treatment. The results of ohmic heated starch's external structure, X-ray diffraction, DSC analysis and RVA were differed from those of conventional heating at the same temperature. Several starches changed more rigid by structure re-aggregation. This change in starch was caused by change of physical, chemical, rheological property. The rheology of ohmic heated potato and corn starch of different heated methods were compared with chemically modified starch. After gelatinization, sample starch suspension (2%, 3%) measured flow curves by rheometer. Cross-linked chemically modified starch's shear stress was decreased with degree of substitution reversibly. Ohmic heated more dramatic, at $60^{\circ}C$. Potato starch's shear stress was less than commercial high cross-linked modified starch. Flow curves of potato starches measured at $4^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$. Showed that Ohmic heated potato starch's shear stress ranging between $4^{\circ}C$ and $20^{\circ}C$ was narrower than modified starch. According to this study, ohmic heated potato starch can be used by decreasing viscosity agent like cross-linked modified starch.

• Microbiology and Biotechnology Letters
• /
• v.22 no.3
• /
• pp.283-289
• /
• 1994

The production of maltose utilizing swollen extrusion starch seems to have many technical advantages, such as, high reaction rate and high yield, production of high purity concentrated maltose, and low energy consumption, over the conventional method utilizing liquefied starch. The characteristics of maltose formation in heterogeneous enzyme reaction system comtaining swollen extrusion starch was investigated using fungal $\alpha $-amylase. The influence of extrusion conditions on structure of extruded starch, such as, degree of gelatinization, water absorption index, and water solubility index was analyzed. The relationship between the structural features and maltose forming reaction was investigated, and the result was analyzed in terms of surface reaction of insoluble extruded swollen starch. The characteristics of maltose formation from swollen sxtrusion starch was compared using endo-type fungal $\alpha $-amylase and exo-type $\beta $anylase, and the structural trasformation of extruded starch was also observed to clarify the reaction mechanism.