• Applied Biological Chemistry
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• v.40 no.4
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• pp.289-293
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• 1997

The effects of different types of additives(sucrose fatty acid ester(SE), oligosaccharide and alum) on 40% nonwaxy rice starch gels stored at $20{\pm}1^{\circ}C$ were investigated by ${\alpha}-amylase-iodine$ method, X-ray diffractometry and differential scanning calorimetry. The addition of SE retarded the retrogradation of gels throughout storage period and the antistaling effect of SE was increased with increasing concentration. Oligosaccharide(0.1%) inhibited the retrogradation, but oligosaccharide(0.1% or 0.5%) retarded the retrogradation at early stage of storage, and stimulated the retrogradation after 3 days. Alum of 0.1% level retarded the retrogradation, but 0.3% level activated the retrogradation after 24 hours and 0.5% level did after 12 hours. The effect of additives on the retrogradation of rice starch gels showed the different tendencies at the level of additives. On 0.1% level, the effect of those was similar but on 0.5%, the degree of retardation increased in order of oligosaccharide, SE1170, alum, no addition for up to 2 days of storage and SE1170, no addition, oligosaccharide, alum for 3 days of storage.

• Food Science of Animal Resources
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• v.41 no.4
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• pp.731-738
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• 2021

Herein, a novel analytical method using a high-performance liquid chromatography-fluorescence detector (HPLC/FLD) is developed for rapidly measuring an L-carnitine ester derivative in infant powdered milk. In this study, solid-phase extraction cartridges filled with derivatized methanol and distilled water were used to effectively separate L-carnitine. Protein precipitation pretreatment was carried out to remove the protein and recover the analyte extract with a high recovery (97.16%-106.56%), following which carnitine in the formula was derivatized to its ester form. Precolumn derivation with 1-aminoanthracene (1AA) was carried out in a phosphate buffer using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) as the catalyst. Method validation was performed following the AOAC guidelines. The calibration curves were linear in the L-carnitine concentration range of 0.1-2.5 mg/L. The lower limit of quantitation and limit of detection of L-carnitine were 0.076 and 0.024 mg/L, respectively. The intra- and interday precision and recovery results were within the allowable limits. The results showed that our method helped reduce the sample preparation time. It also afforded higher resolution and better reproducibility than those obtained by traditional methods. Our method is suitable for detecting the quantity of L-carnitine in infant powdered milk containing a large amount of protein or starch.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.763-767
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• 2005

Effect of ${\alpha}-amylase$ and various emulsifiers on characteristics of bread dough were examined. Fungal or bacterial ${\alpha}-amylase$ and various emulsifiers including monoglyceride (MG), sodium stearoyl-2-lactylate (SSL), and diacetyltartaric acid ester of mono- and diglycerides (DATEM) were added to bread dough both individually and as mixtures. Rheological characteristics of various bread doughs were examined through falling number, farinograph, alveograph, and rapid visco analysis. Results obtained showed falling number decreased via degradation of starch by ${\alpha}-amylase$. In farinogram, addition of ${\alpha}-amylase$ and emulsifiers in dough decreased consistency, water absorption, mechanical tolerance index, and dough development time. Farinogram characteristic was improved by adding SSL+MG to dough formula. Similar to farinogram addition of ${\alpha}-amylase$ and emulsifiers in alveogram of dough decreased overpressure, extensibility, swelling index, and deformation energy. Whereas addition of ${\alpha}-amylase$ did not affect pasting temperature, viscosity of dough tended to decrease.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.46-52
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• 2010

Yakju, a Korean traditional alcoholic beverage, is made from glutinous-rice flour or rice starch with nuruk. In this study, we investigated that fermentation characteristics in yakju was made with glutinous rice and pretreatment. The yeast and nuruk were used Y90-9 and SP1800 (a kind of improved nuruk), respectively. pH and brix degree of yakju, brewed with glutinous rice flour by heating, were higher than the others during fermentation process. Total acid contents were 0.2~0.3 and the highest alcohol degree (15.75%(v/v)) was fermented glutinous rice flour by heating. Reducing sugar contents were 3.5-3.9 mg/mL. Yakju, which brewed with glutinous rice flour, of amino acid degree, UV absorbance and color degree was higher than yakju which brewed with glutinous rice starch. Succinic acid was the highest organic acid among 6 organic acids and free sugar contents described as glucose > maltose > fructose. Twenty one components were identified including 3 alcohols, 17 esters and one aldehyde. Of these, ethyl palmitate, which was described as mild flavor, was the highest %area except ethyl alcohol. Overall, the fermentation performed using glutinous rice flour by heating and improved-nuruk showed the best results for yakju production.

• Food Science and Preservation
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• v.22 no.3
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• pp.353-360
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• 2015

Yakju, a Korean traditional alcoholic beverage, is made from rice and Nuruk. In this study, the fermentation characteristics of Yakju was investigated using rice and rice starch. Ingredients was classified into raw material (rice, rice starch) and starter (enzyme supplements, modified Nuruk, traditional Nuruk, and yellow rice koji) for fermentation. The crude protein content of rice, rice starch, and starter were determined as follows (%): rice 6.69, rice starch 0.44, enzyme supplements 7.84, modified Nuruk 15.29, traditional Nuruk 14.28, and yellow rice koji 7.28. The alcohol content of rice with traditional Nuruk ($20.13{\pm}0.12%$) was higher than other Yakju. The concentration of organic acids of rice starch-based Yakju (389.83~538.34 mg%) was higher than that of rice Yakju (259.27~357.70 mg%). The concentration of nitrogen compound of rice Yakju (498.38~5976.93 ppm) was higher than that of rice starch-based Yakju (600.43~4463.79 ppm). In line with these findings, further studies will be necessary for the quality analysis of the rice, rice starch and fermented starter (enzyme supplements, modified Nuruk, traditional Nuruk and yellow rice koji).

• Journal of Korean Society of Environmental Engineers
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• v.34 no.11
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• pp.735-742
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• 2012

This study tried to find a suitable method for enhancing the foam stability of cationic surfactants that normally generate less foam or no foam. Several trials were made to enhance the foam stability: addition of anionic surfactant, colloids and polymer. Cationic starch (CA-ST) did not form foam at all, while the foam stability of two other cationic surfactant also showed low levels; methyl triethanol ammonium methyl sulfate distearyl ester (CEQ90) for 46 sec. and Cetyl trimethyl ammonium chloride (CM29) for 31 seconds. Foam stability of cationic surfactants were significantly affected by addition of anionic surfactant, sodium dodecyl sulfate (SDS). Foam stability of CA-ST was significantly enhanced by addition of SDS, while those of CEQ90 and CM29 were decreased. Addition of colloids ($SiO_2$, kaolin) and polyvinyl alcohol (PVA) enhanced foam stabilities of CEQ90 and CM29. However, CA-ST did not form foam even in the presence of colloids or PVA. Effect of simultaneous addition of colloids and anionic surfactant on foam stability of cationic surfactant showed that foam stability of cationic surfactant was more influenced by addition of anionic surfactant than colloids. Effect of simultaneous addition of PVA and anionic surfactant on the foam stability of cationic surfactant also showed that presence of anionic surfactant significantly affect the foam stability of cationic surfactant. Foam stability of CA-ST was greatly increased to 8,780 seconds by addition of SDS 0.14% and PVA 2.5%. The foam stability of CA-ST was 8 times higher than CEQ 90. This study suggested that cationic surfactants not forming foam can generate foam by addition of anionic surfactant and its stability can be additionally increased by addition of colloids and PVA. The study results showed that enhancement in foam stability of cationic surfactant was prominently affected by the concentration of anionic surfactant added.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.59-67
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• 2006

Effects of ${\alpha}-amylases$ and emulsifiers on characteristics of frozen bread dough were examined during 12 weeks of storage. Fungal or bacterial ${\alpha}-amylase$ and various emulsifiers, including monoglyceride (MG), sodium stearoyl-2-lactylate (SSL), and diacetyltartaric acid ester of mono- and diglycerides (DATEM), were added to frozen dough individually and as mixtures Height of frozen dough at maximum development time, total volume of $CO_2$ gas, and retention volume increased with increasing content of emulsifiers. indicating addition of enzymes and emulsifiers had significant effect on flexibility of starch-gluten complex in dough. Frozen dough made with bacterial ${\alpha}-amylase$ showed slightly higher pH during storage than that of frozen dough with fungal ${\alpha}-amylase$. Bread made from frozen dough prepared with both enzymes and emulsifiers showed lower specific loaf volume than that of control during storage, whereas highest specific loaf volume was obtained with addition of fungal ${\alpha}-amylase$ with SSL+MG and bacterial ${\alpha}-amylase$ with MG.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.3
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• pp.7-16
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• 1997

The constituents of deposits on paper machine and holes/spots in paper have been studied by consequently a combination of analytical techniques, such as FTIR, Py-GC-MS, and. EDS. FTIR spectroscopy was used prior to Py-GC-MS and EDS analysis, as preliminary analysis technique. The analysis of organic components were carried out with the use of a pyrolysis unit connected to a GC-MS, and inorganic components in ash were analysed by SEM equipped with an EDS analyzer after pyrolysis at 59$0^{\circ}C$. The deposits on the dryer section were complex pitch, which was the mixture of the organic contents of fatty acid ester and starch, and the inorganic contents of talc, clay, and calcium carbonate. The complex pitch was estimated to come from the coated broke. We knew the deposits on the metering rod of sym-sizer were associated with the interaction of unstable AKD and CaCO$_3$. The compositions of holes or spots varied considerably and were associated with chemical interaction within the system. The holes, spots, and blotches in the finished paper were PE and PP that were streamed out from pulp sources, complex pitch that were caused by the interaction of the different additives in the system, polymer such as flexible PVC that used for the prop of palette, and hot melt as adhesives that came from the inadequate handling of broke. In addition, we identified that poly(caprolactam) which is used for forming fabrics or press felts, could be mixed with the raw materials by accident and results in streak on coating.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.39-45
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• 1984

The effects of foliar application of phosphate was investigated in the light of plant physiological point of view. The phosphate applied on the foliar both in meiosis and heading time was penetrated considerably into the rice. The amount of P absorbed by foliar application at high temperature was higher than that at low temperature but still considerable amount of P was absorbed at low temperature. The phosphate applied on younger flag leaf was absorbed more vigorously than the second and third leaves. The absorbed P on leaf was translocated to the panicle, especially on the brown rice starch, then moved to another panicle wherever the phosphate was needed. The major fraction of absorbed P under high temperature condition was T.C.A. soluble-Ba insoluble phosphate of mainly phytic form but Ba soluble-EtOH insoluble fraction, sugar phosphate ester, was identified as dominant P under low temperature condition.

• Applied Chemistry for Engineering
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• v.9 no.1
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• pp.135-140
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• 1998

The constituents of deposits on paper machine and holes/spots in paper have been analyzed by a combination of analytical techniques, such as FTIR, Py-GC-MS, and EDS. FTIR spectroscopy was used prior to Py-GC-MS and EDS analysis, as a preliminary analysis. The analysis of organic components was carried out with a pyrolysis unit connected to a GC-MS, and inorganic components in ash were analyzed by SEM equipped with an EDS analyzer after pyrolysis at $590^{\circ}C$. The deposits on the dryer section were complex pitch, which was the mixture of the organic components of fatty acid ester and starch, and the inorganic components of talc, clay, and calcium carbonate. The complex pitch was estimated to come from the coated broke. We knew the deposits on the metering rod of sym-sizer were associated with the interaction of unstable alkyl keten dimer(AKD) and $CaCO_3$. The compositions of holes or spots varied considerably and were associated with chemical interaction within the system. The holes, spots, and blotches in the finished paper were PE and PP from pulp sources, complex pitch that were caused by the interaction of the different additives in the system, polymer such as flexible PVC that was used for the prop of palette, and hot melt as adhesives that came from the inadequate handling of broke. In addition, we identified that poly(caprolactam) which is used for forming fabrics or press felts, could be mixed with the raw materials by accident and results in streaks on coating.