• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.627-632
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• 1991

The heat treatment indicators such as HMF contents, lactulose contents and whey protein denaturation rates were measured to refer to the heat treatment intensity of domestic market infant formulae. The HMF contents showed $21.0{\sim}43.9{\mu}mol/l:$ in the case of powder types, the HMF contents in enriched nutrient products(ii) were higher whereas in the case of liquid types they were packed in cans(i). The lactulose contents showed $2.5{\sim}11.4mg/100ml$ in the powder type and $27.0{\sim}164.8mg/100ml$ in the liquid type. There was much difference in the lactulose contents according to the product types. Compared with the ADPI standards, most of infant formulae were considered to be medium-heat class. The whey protein denaturation rates were $1.1{\sim}69.4%$ in the powder type and $37.4{\sim}71.3%$ in the liquid type.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.119-124
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• 1987

Combined cryoprotectants (C.C.) were formulated to depress freezing points of strawberry pulp and orange juice concentrate to ${-15}^{\circ}C$, and quality changes in fruit pulps during storage ai ${-15}^{\circ}C$ in the liquid state were investigated. C.C. suitable for strawberry pulp consisted of sucrose (2.5%, w/w), glucose (12.7%), fructose (12.7%), glycerol (1%), propylene glycol (1%) and ascorbic acid (0.1%), and that for orange juice concentrate containing 48% solids glucose (5%), fructose (5%), glycerol (4%) and citric acid (1%). When quality of fruit pulps was compared among control and those with C.C., quality of fruit pulps stored with added C.C. was at least as good as control, except treatment B which had significantly lower overall preference. Strawberry jam prepared from pulp stored for 4 monthes did not show any significant quality differences among control and treated samples. The results of this study indicated that fruit pulps could be stored with added C.C. in the liquid state at the frozen storage temperature, while maintaining qualities at least as good as the conventionally frozen stored products.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.55-63
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• 1992

The essential oil of Korean ginger(Zingiber officinale Roscoe) was isolated by liquid carbon dioxide extraction method and fractionated into one hydrocarbon fraction and two oxygenated hydrocarbon fractions by using silica gel column chromatography. The compositions of the resulting oils were investigated by GC and GC-MS spectrometry. Out of 102 identified compounds, 44 were identified by comparing GC retention time and mass spectral data with authentic samples and 58 were tentatively identified according to mass spectral data only. The major compounds of hydrocarhon fraction were $zingiberene,\;{\beta}-sesquiphellandrene,\;{\gamma}-bisabolene,\;{\gamma}-cardinene,\;ar-curcumene$, and those of oxygenated hydrocarbon fractions wee geranal, sesquisabinene hydrate, borneol and zingiberenol. The major compounds of ginger oil were zingiberene, $citronellol+{\beta}-sesquiphellandrene,\;geranial,\;{\gamma}-bisabolene\;and\;ar-curcumene+geranyl\;acetate$, and ginger oil contained higher amounts of sesquiterpene hydrocarbons. The yield of extract was 6.96%.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1470-1475
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• 2009

The seed coat of the black soybean contains 3 main anthocyanins such as delphinidin-3-O-$\beta$-glucoside, cyanidin-3-O-$\beta$-glucoside, and petunidin-3-O-$\beta$-glucoside. As a part of our effort on discovering and breeding new black soybean cultivars which possesses specific anthocyanin component rich, we determined the anthocyanin profiles of the 2 cultivars recently developed soybean cv. Gaechuck #1 and cv. Gyeongsang #1, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and compared their content and identity with those of previously known 10 cultivar controls. The Cosmosil-$5C_{18}$-AR-II column were selected for the analysis because of the best peak separation. The column temperature was set up at $35^{\circ}C$. The mobile phase consisting of water containing 0.5%(v/v) formic acid and methanol gave good separation between the 3 anthocyanin analytes and internal standard (quercetin 3-O-$\beta$-rutinoside) and peaks with suppressed tail. The MS/MS spectra of each individual anthocyanin standard were detected in positive electron spray ionization (ESI) modes. It was disclosed that the anthocyanin contents of the soybean cv. Gaechuck#1 and cv. Gyeongsang#1 are roughly higher than those of the 10 controls.

• Food Science and Preservation
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• v.11 no.4
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• pp.472-477
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• 2004

This study was carried out to investigate the effect of liquid calcium(LC) on the quality of kimchi during fermentation. LC retarded the decreasing rate of pH and the increasing rate of titratable acidity during fermentation at $10^{\circ}C$, and the effect was more conspicuous at $7.0\%(v/w)$ than at $3.5\%(v/w)$ in each LC type. Microbial counts of total and lactic acid bacteria were lower in LC added kimchi than control before 8 days but higher in LC added kimhi after 8 days. Changes in color of a value were gradually increased, but L and b value were decreased. Calcium content of added LC on kimchi; A concentration $3.5\%(v/w),\;7.0\%(v/w)$ were $103{\sim}110\;mg\%,\;145{\sim}163\;mg\%$ and B concentration $3.5\%,\;7.0\%$ were $140{\sim}151\;mg\%,\;210{\sim}220\;mg\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.404-410
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• 2021

Although, mouse bioassay for the monitoring of azaspiracids (AZAs) toxins in shellfish has been used previously, the reported method has low sensitivity and it is time-consuming. Recently, there is an interest in the quantitative analysis of AZAs using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The purpose of this study is to verify the simultaneous analysis of AZAs in shellfish and tunicate in Korea using LC-MS/MS. To validate the method, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, and repeatability were determined. All standard compounds were analyzed within 7 min. The correlation coefficients (R²) of the standard solution was higher than 0.9995 (within the range of 0.8-10.0 ㎍/L). The LODs and LOQs of AZAs in shellfish were 0.08-0.16 ㎍/kg and 0.23-0.50 ㎍/kg, respectively. The accuracy and precision of the method for determining AZAs in shellfish were 87.1-93.0% and 1.23-4.91%, respectively. Consequently, the verified LC-MS/MS method is suitable to analyze AZAs in shellfish and tunicates in Korea.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.143-152
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• 2015

Vitamin D contents in agricultural products and foods were quantified by high performance liquid chromomatography (HPLC) with a UV/Vis detector, using external standard methods. The results were confirmed with liquid chromatography tandem mass spectrometry (LC-MS/MS). After homogenization, samples were hydrolyzed by direct alkali saponification. Thereafter, fat-soluble components were extracted with n-hexane containing 0.01% butylated hydroxytoluene (BHT). Vitamin D contents in cereals were found to be in the range of $1.882{\sim}4.856{\mu}g/100g$. Juda's ear and oak mushroom contained high amounts of vitamin D, at 363.85 and $199.42{\mu}g/100g$ of edible portion, respectively.

• Preventive Nutrition and Food Science
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• v.9 no.1
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• pp.14-20
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• 2004

Bacillus strains capable of producing fibrinolytic enzyme were isolated from traditional fermented Korean soybean paste and Japanese fermented soybean (Natto). Among the 16 strains, a selected Bacillus sp. was identified as bacillus firmus, with 80.7％ homology, by API kit analysis. Seed starter or B. firmus NA-1 was prepared with 5％ soymilk prepared from micronized soybean powder. To produce fibrinolytic enzyme by B. firmus NA-1 the liquid culture was performed with NB broth (pH 7.0) fortified with 1％ galactose, 0.1% tryptone, and 0.5% $K_2$HPO$_4$, by shaking with 180 rpm at 37$^{\circ}C$. Fibrinolytic enzyme activity reached the highest value at 7.8 unit/mL (plasmin unit) after fermentation for 72 hr. The crude fibrinolytic enzyme showed higher relative activity in the range of pH 7.0∼9.0. The activity of crude fibrinolytic enzyme was well maintained even after concentration by the vacuum evaporation at 5$0^{\circ}C$ for 1 hr.

• Korean Journal of Food Science and Technology
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• v.10 no.1
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• pp.16-26
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• 1978

Establishment of detecting method for adulterated foods was attempted by the use of fluorescence at the irradiation of UVSL-25 mineralight. Visual observation and spectral analysis of superficial luminescence appeared to be improper as detecting method of food substances. Absorption and fluorescence spectra of powdered substances suspended in liquid paraffin or liquid sample revealed characteristic patterns depending on foods. Uniformity of samples was shown to be the most important factor to obtain reproducible results.

• Food Engineering Progress
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• v.22 no.4
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• pp.295-303
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• 2018

Polyphenol profiles, physicochemical properties, antioxidant activities, and inhibitory effect of adipocyte differentiation of Houttuynia cordata fermented with Lactobacillus brevis B84 were evaluated. Six polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and the results were compared with total phenolic content by a spectrophotometric method. The total amount of the identified polyphenols was lower than that determined by the spectrophotometric method. However, the fermentation process influenced polyphenol composition such as content of vanillic acid and caffeic acid. The phytochemical profiles were evaluated by high-performance liquid chromatography with UV and electrospray ionization mass spectrometry detection ($HPLC-DAD-ESI-MS^n$). Total sugar and reducing sugar contents decreased after fermentation. Antioxidant activities such as DPPH, ABTS, and superoxide anion radical scavenging and reducing power were evaluated to compare the beneficial effect after fermentation. Fermented H. cordata increased the lipolytic effect in 3T3-L1 adipocytes. Overall, the results indicate that the fermentation of H. cordata with L. brevis B84 produces changes of phenolic compounds, antioxidant activity, and lipolytic effect.