• Food Science and Biotechnology
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• v.17 no.4
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• pp.705-712
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• 2008

Sweet potato starch was modified using Thermus aquaticus $\alpha$-1,4-glucanotransferase ($Ta{\alpha}GT$), and its structural and rheological properties were investigated. $Ta{\alpha}GT$-modified starch had a lower amylose level and molecular weight than raw starch. The chain length distribution showed an increased number of short and long branched chains and the formation of cycloamyloses. Compared with raw starch, $Ta{\alpha}GT$-modified starch displayed a lower gelatinization enthalpy and a wider melting temperature range. The X-ray diffraction of $Ta{\alpha}GT$-modified starch was a weak V-type pattern with distinct sharp peaks at 13 and $20^{\circ}$. Scanning electron micrographs of modified starch exhibited big holes on the surface and the loss of granular structure. The frequency sweep measurement revealed that the gel of $Ta{\alpha}GT$-modified starch was more rigid than raw starch gel. However, the structure of modified starch gel was destroyed by heating at $75^{\circ}C$, and a firm gel was re-formed by subsequent storage at $5^{\circ}C$, indicating thermoreversible property.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.60-65
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• 2001

Physicochemical properties of 4 kinds of domestic and 7 kinds of foreign starch vermicelli (1 from Chinese, 6 from Japan) were determined. Peak temperature of starch vermicelli measured by DSC were $42{\sim}48^{\circ}C$ which were much lower than gelatinization temperatures of their raw material starches. X-ray diffraction peaks of starch vermicelli were not sharp compared with those of raw material starches which indicated that starches were gelatinized by heating and retrograded by cooling and freezing during production of starch vermicelli. Hardness and compression slope of sweet potato starch vermicelli measured by rheometer were respectively $9,500{\sim}11,000\;g/cm^2$ and $18,000{\sim}26,000\;g/cm^2$ which were twice higher than those of corn starch vermicelli. Cooking loss of corn starch vermicelli, which was 19.8%, was higher than that of sweet potato starch vermicelli, $4.2{\sim}6.6%$ and mung bean starch vermicelli, 7.7%. In changes of thickness of starch vermicelli during cooking i.e swelling ratio, sweet potato starch vermicelli had $58{\sim}69%$ of swelling ratio, which was higher than that of corn starch vermicelli, 50%. Corn starch vermicelli, which was relatively less elastic and easily broken, was shown to be inferior to that of sweet potato starch vermicelli in overall quality.

• Korean Journal of Microbiology
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• v.7 no.4
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• pp.153-158
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• 1969

It is the most important thing to substitute sweet potato for wheat flour as the brewing material of Maggerley(Korean wine) in order to save precious wheat flour which is now consumed as the sole material in it. In this study, the fermenting mash material has been prepared with combination of wheat (KIorean wine) as a first step of sabing wheat flour consuming. The combination ratio of wheat flour and sweet potato starch in mashing, in this experiment, are such as mashing plot of 100% wheat flour (No.3 plot), 50% wheat flour plus 50 % of sweet potato starch (No.2plot), 30% wheat flour plus 70% starch syrup of sweet potato (No. 4 plot), and 60% wheat flour plus sweet potato starch (No. 1 plot). The results of fermentation and chemical components of each mash in experimental plot are as following : 1. Alocholic fermentation was most vigorous in No.4 plost among them, the next are in order to hydrolyze and break down the protein sourece to glucose and amino acid, the new enzymic source were added in experimantal amsh before putting yeasts, those enzymic sources have been developed and prepared in this laboratory No.4 and No.2 plot at same degree. Generally, the activities of alcholic fermentation of all plots are vigorous and fair. The acidity of each fermented mash is in the rangw of 3.7-4.8. 2. Amounts of amino acids in fermented mash are in the range of 145 mg per 100 ml and 158 mg for all experiments, and these amounts are much more than those of present commerical Maggerley. However, the amount of it in the No.4 plots is much less among the m, this is due to the lack of protein source in starch syrup. 3. Amounts of organic acids in fermented mash are in the range of 0.44g per 100ml and 0.62g, these amounts are generally much more than those of the present commercial Maggerley. 4. The result of sensory test for the experimental Maggerley shows good taste and flavour in comparison with those of commercial Maggerely. 5. It is proved that these experimental fermentation of Maggerley is succesful in the partial substitution of sweet potato starch potato starch for wheat flour, and it is also be able to make a good Maggerley in all aspects of quality.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.88-93
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• 2010

The principal objective of this study was to evaluate the physicochemical characteristics of brown rice Dasik prepared with different 5 levels(0, 25, 50, 75, 100%) of modified potato starch powder. We assessed the general compositions, Hunter's color values, the mechanical characteristics, and conducted a sensory evaluation analysis of brown rice Dasik at room temperature($20^{\circ}C$). The more modified potato starch powder composition was increased, the content of ash, protein and fat were significantly decreased(p<0.05). We noted that the luminance of samples were increased the more modified potato starch powder composition was increased, but in Hunter's a and b values were decreased. With regard to the mechanical properties of the Dasik samples, we noted significant differences in hardness, gumminess, chewiness but no differences in springiness, cohesiveness and adhesiveness were detected. The more modified potato starch powder composition was increased, the more the score of hardness, gumminess and chewiness were higher. The results of sensory evaluation showed that there were significant differences on the color, sweetness, mouth-feel, chewiness, overall quality of the Dasik samples(p<0.05). The score of brown rice Dasik with 50%(w/w) modified potato starch(BM2) in color, mouth-feel, chewiness, overall quality were significantly increased than those of other samples.

• Culinary science and hospitality research
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• v.20 no.3
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• pp.148-160
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• 2014

This study was performed to find out the optimum condition of a thickening agent for brown sauce. Four thickening agents of non-glutinous rice, glutinous rice and potato starch, and roux as control thickeners were tested with various concentrations of each thickener to investigate the quality characteristics of brown sauce samples. The moisture contents of the brown sauce samples thickened with non-glutinous rice, glutinous rice and potato starch showed higher than that of the brown sauce samples thickened with roux. The brown sauce samples thickened with non-glutinous rice and potato starch had higher viscosity than the samples with glutinous rice and roux. The brown sauce with roux showed the highest on Hunter's color L and b value and the brown sauce with non-glutinous rice showed the highest a value. The brown sauce samples with 11% of roux, 11% of non-glutinous rice powder, 12% of glutinous rice powder and 6% of potato starch showed significantly higher scores in the acceptance test. The brown sauce with 6% potato starch resulted in the highest score in brown color, gloss, and transparency, and the brown sauce with 11% of roux showed the highest roast smell. The brown sauces with 6% potato starch and 11% of roux showed higher viscosity than the samples with 11% of non-glutinous rice and 12% of glutinous rice.

• Food Engineering Progress
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• v.21 no.3
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• pp.280-285
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• 2017

The objective of this study was to increase the efficiency of starch extraction from potato sludge by different concentration of food-grade hemicellulase. The potato sludge, which is a by-product of potato processing industry, was treated with food-grade hemicellulase. Starch extraction efficiency displayed no significant difference in hemicellulase concentration. The purities of potato starch increased from 83.40 to 95.91, 97.44, 95.58, and 97.79%, with treated 0.5, 0.75, 1.0, and 1.5% hemicellulase, respectively. The physicochemical properties of the starches, such as granule structure, particle size, pasting, and thermal transition, were not affected by the concentration of hemicellulase. These results indicate that food-grade hemicellulase treatment is an efficient method for starch extraction from potato sludge.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.572-580
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• 2013

This study was carried out to evaluate the effect on properties of restructured jerky by the addition volume of additives. The treatments were divided into glutinous rice flour, potato starch, soybean and acorn powder. Moisture content, water activity ($a_w$), thiobarbituric acid reactive substances (TBARS), color, yield and sensory evaluation were performed. The moisture contents of four types of restructured jerkies were in the range of 8.92-12.47%, and were lower than that of the control (17.92%). Water activity tended to decreased with increasing addition of all treatments. The restructured jerkies containing glutinous rice flour, potato starch, soybean and acorn powder had lower TBARS than the control. The drying yield tended to increase with increasing amount of additives. In the sensory evaluation results, the highest overall acceptability was found in jerky containing glutinous rice flour, potato starch, and acorn powder when the addition was 9%, while that for soybean powder was determined to be 5%. These results suggest that 9% additions of glutinous rice flour, potato starch or acorn, or 5% soybean powder are optimal addition volumes for the preparation of restructured jerkies.

• Journal of the Korean Society of Food Culture
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• v.20 no.3
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• pp.360-366
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• 2005

This study was conducted to investigate the quality characteristics of low- fat pork patties containing fat replacers. Carrageenan(CA) in combination with pectin(PE) or potato starch(PO) was added as fat replacers and physicochemical properties were evaluated in low-fat pork patties cooked by oven-roasting or pan-frying. Uncooked and cooked pork patties formulated with fat replacers were higher in moisture and ash content and lower in fat content than those of control. The cooking yield and reduction in diameter of pork patties were significantly improved by the addition of fat replacers(p<0.05). Pork patties formulated with CA had the highest fat retention, while CA+PE had the highest water holding capacity. Hunter s L(lightness) value was not different from among patties and a(redness) and b(yellowness) values were higher in carrageenan-based patties than those of control patties. Hardness was higher in carrageenan-based patties than that of control and cohesiveness and springiness showed no difference among patties. Sensory analysis showed that flavor, juiciness and palatability of carrageenan-based patties were superior to control patties and combined use of CA with PE or PO provided improved acceptability of low-fat pork patties over that from using single carrageenan.

• Korean Journal of Microbiology
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• v.10 no.2
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• pp.79-86
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• 1972

The possibility of substituting potato or sweet potato for the wheat, one of the raw materials for soy sauce, was studied by measuring the amylase and proteolytic activities of Koji. Also optimum conditions of Koji making were determined. It was found that substitution of up to 30% (starch content) of wheat content (15% of the total bean and wheat content) with potato yielded good qulity of soy sauce. Use of more than 30% potato yielded a Koji of low enzymatic activity. This was attributed to the high moisture content of potato. It ws also found that substitution of up to 50% (starch content) of wheat content(25% of the total bean and wheat content) with sweet potato yieldede a good quality of soy sauce. But the taste was inferior to the control (the soy sauce which was made with 50% of bean and 50% of wheat).

• Journal of Life Science
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• v.13 no.4
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• pp.481-491
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• 2003

A squid meat has not been utilized for gel products because of its lower gel forming ability. The objectives of this study were as followed; 1) the optimum heating condition on squid meat paste products and 2) the optimum added level for jelly strength of squid meat paste products. Optimum heating conditions of squid meat kamaboko were as followed; setting (pre-heating) at 15$^{\circ}C$ or 55$^{\circ}C$ for 2 hours and heating at 90$^{\circ}C$ for 60 minutes. Effect for jelly strength of starch additives wheat starch, potato starch and com starch were examined. The jelly strength of heat induced gels differed from the levels of additives. In case of adding starch, potato starch was resulted in the superior jelly strength than the other starchs, wheat starch and corn starch, at any levels. Optimum concentration was 10%(w/w) at every additives. Folding test value was B at added 10% and this value was mean good product. Data of jumbo and flying squid meat paste products added potato starch, corn starch and wheat starch of 10% were shown below, jelly strengths were 858${\pm}$34∼1020${\pm}$37gㆍcm and 966${\pm}$33∼l148${\pm}$45gㆍcm and moisture contents were 72.43∼73.04% and 71.61∼72.78%, respectively. To adding edible agar and sea tangle, showed the highest jelly strength (edible agar>sea tangle, flying squid>jumbo squid) at added 0.5%(w/w) concentration.