• Applied Biological Chemistry
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• v.26 no.4
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• pp.211-216
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• 1983

The physicochemical properties of starches isolated from three kinds of waxy ricer were investigated. The average diammeter of Orchal starch granule was 3.6u, and those of Hangang and Baegoon starch granules were 4.8u and 5.6u, respectively. X-ray diffraction patterns of all samples were A types. Optical transmittance of starch suspensions was increased rapidly $60{\sim}62^{\circ}C$, $50{\sim}55^{\circ}C$ and $50{\sim}60^{\circ}C$ in Olchal, Hangang and Baegoon, respectively, and all of them exhibited maximum transmittance $75{\sim}80^{\circ}C$ in range. Initial gelationization temperature by means of amylogram pattern was $60{\sim}61^{\circ}C$, then, Olchal starch had a little higher temperature than others. Raising power of them was $260\sim220$, and then, Olchal starch has a little higher raising power. But, water binding capacity of Baegoon and Hangang were somewhat higher than that of Olchal. Blue values of Olchal and Hangang were similar with 0.13, and that of Baegoon was 0. 14. Alkari numbers of Olchal, Hangang and Baegoon were 4.2, 4.9 and 5.1. The degree of retrogradation of Hangang and Baegoon starch gels were somewhat higher than that of Olchal starch gel.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.235-240
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• 1991

Starch phosphates were prepared from the corn starch mixed with 2% sodium tripolyphosphate by twin-screw extruder with a feed rate of 20 kg/hr and an extrusion temperature of $130^{\circ}C$, and the effects of extrusion variables on the physicochemical properties (target parameters) of starch phosphates were investigated. Interrelations of system parameters (specific mechanical energy and extrudate moisture) and rheological properities of starch was analyzed by using the response surface analysis. Degree of substitution (DS) was increased with increasing the feed moisture, and showed the maximum value at the screw of near 250 rpm, Degree of gelatinization was proportionally increased with increasing the screw speed and decreasing the feed moisture. Apparent viscosity of the paste was increased with increasing the feed moisture, but it was not significantly affected by the screw speed. It was found by scanning electron microscopy that the starch microgranules were much more degradaded, and as consequent result, the intrinsic viscosity was decreased, whereas, water solubility index was increased. The rate of retrogradation of the gels was retarded with increasing DS and decreasing viscosity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.125-132
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• 1983

Dielectric properties of sardine-starch paste with moisture content of 4 to $13\%$ were investigated as functions of moisture and frequency. And the effects of the levels of fat and starch of the mixtures upon dielectric permittivity, critical moisture, were also mentioned. In addition, a theoretical prediction of frequency dependence of dielectric constant which was computed by the lumped circuit of two layer condenser model was evaluated. For the preparation of sardine-starch paste, comminuted sardine meat was washed thoroughly several times in chilled water by soaking and decanting, and finally centrifuged. This procedure was extended longer to provide a low fat sample. The centrifuged meat was mixed with adequate amounts of starch and salt, and ground for 25 minutes in a stone mortar, moulded in the form of disk with 7cm diameter and 1.2cm thickness and then freeze dried. Dried meat disks were cut off for the size of 5.5cm diameter and 1.0cm thickness and their moisture contents were controlled in humidified desiccators with saturated solutions. Dielectric constants of sardine-starch paste tended to decrease frequency was increased showing a critical charge at the moisture called critical moisture content. In case of the sample with $20\%$ starch and $2\%$ salt an average complex permittivity($\epsilon^{\ast}$) at 7 to $8\%$ morsture as the critical moisture content was presented; $\epsilon^{\ast}$=3.37+j 0.39 at 0.1 MHz, $\epsilon^{\ast}$=2.54+j 0.19 at 15 MHz, and $\epsilon^{\ast}$=2.15+j 0.08 at 1.8 GHz, respectively. The theoretically obtained complex permittivity values from the two layer condoner model were in close agreement with these actual measurements under the same conditions, that appeared as $\epsilon^{\ast}$=2.53+i 0.09 at 0.1 MHz and $\epsilon^{\ast}$=2.28+j 0.06 at 15 MHz, respectively. The fast level of the mixture also revealed an influence on dielectric property that defatted neat with $1.0\%$ fat showed a higher hc and $\epsilon^{\ast}$ value than the meat with $4.8\%$ fat. Complex permittivity being related to the moisture level remained nearly unchanged or slightly changed at the moisture range of 4 to $8\%$ but was dispersed widely at higher moisture contents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1467-1474
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• 2006

Fish-frames, which are left after obtaining fillets or muscle during fish processing, consists of useful food components, such as muscle, collagen, calcium, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study was carried out to prepare snack using conger eel frame (SF) for human consumption and also to elucidate food component characterization of the snack. The results of volatile basic nitrogen suggested that conger eel frame was a suitable material for preparing snack. Based on the results of sensory evaluation and costs, starch syrup was an optimal sweetener for preparing snack using conger eel frame. The starch syrup-treated SF appeared safe because the moisture content and peroxide value were below the safety limits described in the guideline of Korea Food and Drug Administration (KFDA). Starch syrup-treated SF was similar in the pattern of fatty acid composition to soybean oil, whereas EPA and DHA were detected in SF. The total content of amino acid in starch syrup-treated SF was 23.9% based on 100 g of raw material. The maj or amino acids were aspartic acid, glutamic acid, glycine and alanine. The total contents of calcium and phosphorus in starch syrup-treated SF were 4.9% and 2.8%, respectively. The Ca/P of starch syrup-treated SF was 1.9, which is a good ratio for absorption of calcium. The SF made with starch syrup was superior in EPA and DHA compositions, total amino acid, calcium and phosphorus contents to commercial snack using eel frame.

• Food Science and Preservation
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• v.8 no.2
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• pp.146-150
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• 2001

The candy was prepared from starch syrup and sugar added with puree, extract and powder of Doraji, respectively. When three times extracted with 95% ethanol for 12 hours at $25^{\circ}C$ and 4 hours at 51$^{\circ}C$ and 78$^{\circ}C$, the extract contents were 22.6%, 25.8% and 25.3%, respectively. L-value of candy which was made of puree and extract of Doraji was lower than that of control. As the content of puree and extract of Doraji is increased, L-value was decreased. In case of added with puree, extract and powder, a and b-values were higher than those of control. Quality of the candy in sensory evaluation was the best when 20% of puree, 2% of extract and 5% of powder were added to the starch syrup and sugar, respectively. The result of preference test with various model, Bokjumony (Korea traditional purse) was the best in eye freel and ellipse was the best in mouth feel. The calories of candy were 2999.6 ㎉/100g in puree 20%, 358.3 ㎉/100g in extract 2% and 352.1 ㎉/100g in powder 5%.

• Journal of Nutrition and Health
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• v.19 no.1
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• pp.3-15
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• 1986

This study was intended to investigate the rheological properties of the development formula of infant foods and the results are summarized as follow ; 1) Consistency of starch solutions measured by Brabender Anylograph and Brookfield viscometer showed that waxy rice and riece with malt had lower consistency and more rheological stability.The flow type of tested raw materials and formula was found to ？ pseudoplastic, as judged by n-value of 0.332 -0.692, and no yield value. 2) The influenced of temperature on consistency could be accounted for by the equation, In (n) = K(1/T) + const. this relationship indicated that consistency of tested sample increased as temperature decreased. The consistency of waxy rice, rice with malt and formula A were less affected by the temperature change. 3) Infant foods with malt(formula A ) ad with waxy rice maintained better freeze-thaw stability in terms of consistency and starch aggregation indicating that this infant food could be stored for a long term in the freezer section of the home refrigeratory without adverse effect on the product quality. 4) From the above experiments, it would necessarily follow that infant food can be easily made at home the food-stuffs generally available around us, and that the easiest and safest way to store them lies in making them into semisolid state, and in keeping them in frozen state.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.93-96
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• 1967

Especially, we mainly dealt on the isolation of mold in the sample of the Korean products, Kock Ja. The kinds of the isolated strain are such as these, Rhizopus, Mucor, Aspergillus oryzae sp., aspergillus niger sp., Penicillum and Flungi Imperfecti. The action of the starch saccharification of isolated strain and the order of liquefying action are follows: The saccharification power was R-l>R-2>M-2> Kock Ja>M-1>O-2>N-1>O-4 The liquefying power was R-1, R-2>0-2>0-4>M-2, Kock Ja>M-1>N-1 We compared the pH's saccharification curve of each kind of strain with Kock Ja. The most suitable pH value of R-1, R-2 was the closest to pH 4. 0, close value with Kock Ja. The Rhizopus species on the saccharification action of each kind of strain in regard to raw wheat starch was stronger than other kinds of strain. We think that to generalize the above result, the Rhizopus species consists of an important strain of this Kock Ja, and is an important factor for the saccharification action of Kock Ja and the existence of Mucor species as well.

• Journal of the Korean Home Economics Association
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• v.42 no.2
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• pp.213-227
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• 2004

This study was attempted to investigate the sensory and textural characteristics of mungbean starch gels with soy bean oil and sucrose fatty acid ester(SE) addition during room temperature storage. Freshly prepared mungbean starch gels, with and without soy bean oil and SE, were stored at 25$^{\circ}C$ for 24, 48 and 72 hours. The color value, syneresis, texture and sensory properties of the gels were measured. The lightness(L) of the gels with soy bean oil and without additives was similar whereas that with SE was lower than that without additives. Syneresis of the gels with soy bean oil and SE was lower than that without additives. Rupture stress, rupture strain and rupture energy of the freshly prepared gel with 2∼4% soy bean oil were increased, but there were no differences in rupture properties between the gel with soy bean oil and that without additives. Rupture stress, rupture stain and rupture energy of all the gels with SE were decreased. Addition of soy bean oil to the gel did not change the texture profile of the gel, whereas hardness, springiness and chewiness of the gel with SE were decreased. In sensory evaluation, the acceptability of freshly prepared gel with soy bean oil was similar to that without additives, whereas that of the gel with 2% soy bean oil stored for 24 hours was higher than that without additives. The acceptability of the gel with SE was decreased significantly.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.584-587
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• 2007

The effect of molar substitution (MS, 0.030-0.118) on the dynamic rheological properties of hydroxypropylated rice starch pastes (5%, w/w) was investigated by small-deformation oscillatory measurements during aging. The magnitudes of storage (G#) and loss (G") moduli measured at $4^{\circ}C$ before aging increased with an increase in MS in the range of 0.030-0.118, while those of tan ${\delta}$ (the ratio of G"/G#) decreased. The G# values of hydroxypropylated rice starches, as a function of aging time (10 hr) at $4^{\circ}C$, increased rapidly at the initial stage, and then reached a plateau region at shorter aging times. However, for the native starch, the plateau values were not observed for G# after a long aging time. Increasing the MS resulted in a decrease in plateau values. The rate constant (K) for structure development during aging was described by first-order kinetics. The K values of hydroxypropylated rice starches at 0.086 and 0.118 MS were much lower than the K value at 0.030 MS.

• Applied Biological Chemistry
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• v.33 no.1
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• pp.79-86
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• 1990

Cyclodextrin hydrolase from Bacillus stearothermophilus KFCC 21203 was purified and the properties of the purified enzyme were investigated. The enzyme was purified 15 folds with 77 % recovery by ammonium sulfate fractionation, DEAE-cellulose chromatography, and Ultro AcA 34 gel filtration. The specific activity and the molecular weight of the enzyme were 1.30 units/mg protein and about 29,500, respectively, The maximum activity of the enzyme was shown at $55^{\circ}C$ and pH 5.5. However, stable temperature and pH were $40^{\circ}C$ and $5.0{\sim}8.0$, respectively. The Km value for ${\gamma}-cyclodextrin$ was $3.78{\times}10^{-3}$ M. The degradation activity of the enzyme was selectively high for ${\gamma}-cyclodextrin$, and very low for ${\beta}-cyclodextrin$, but not for ${\alpha}-cyclodextrin$. The decomposed products of ${\gamma}-cyclodextrin$ were mainly glucose and maltose, and a little mlatotriose. The activity of the enzyme was very high for amylose, potato starch, corn starch, amylopectin and maltooligomer, and relatively high for glycogen and dextrin. The decomposed products of them were mainly glucose and maltose.