• Journal of Korean Society of Water and Wastewater
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• v.21 no.6
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• pp.671-678
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• 2007

2-methylisoborneol (MIB) is a musty odor compound produced as a secondary metabolite by some cyanobacteria and actinomycetes. It is lead to distrust in tap water due to taste and odor. It is well known that activated carbon (AC) adsorption is the best available technology to remove 2-MIB and geosmin. In this study, physical characteristics of virgin AC and reactivated AC was compared. The effect of variation of NOM molecular weight on adsorption of 2-MIB in virgin AC and reactivated AC were also evaluated. BET surface area was decreased by 13 to 23% and total pore volume was decreased by 18 to 21% due to first and second reactivation compare to the virgin carbon. However, mesopore volume ($V_{meso}$) was increased about 14% after reactivation. It showed that micropore volume was decreased and move to mesopore or macropore after reactivation. Decreased adsorption capacity of 2-MIB was greatly related to below 3000Da. Adsorption capacity of 2-MIB was rather greater in virgin AC than in reactivated, which is strongly related to micropore volume.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1071-1075
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• 2009

Allyl isothiocyanate (AI), a volatile compound of mustard, has excellent antimicrobial effects, but its volatility hinders its wide usage as an ingredient of food products. Microencapsulation technique, therefore, was applied for delaying the release time of AI. For delaying the release time of AI, the mustard powder, which contained AI, was microencapsulated with 5% modified starch by using fluidized bed processing. The efficiency of the controlled release of AI at various pH was analyzed by the head space (HS) analysis and solid phase microextraction (SPME) method using gas chromatography (GC). Also, modified starch encapsulated powder was added into kimchi for applying in food industry. As the result, the release time of AI was delayed by microencapsulation with modified starch and the higher pH could be the faster release of AI. Also, the period until the pH values and total acidity of kimchi reached up to 4.5 and 0.6%, which give its malsour taste, was extended by microencapsulation. These results showed that modified starch encapsulated powder could prolong the preservation in food system.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.351-356
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• 2006

In this study, we investigated the effect of adding a 1, 3, or 5% solution of germinated brown rice concentrate (GBRC) to fermented kimchi. During fermentation, the concentration of free amino acids and essential amino acids increased with increasing concentrations of GBRC. In particular, higher levels of free amino acids were associated with a sweet taste compared with controls. The ${\gamma}$-aminobutyric acid (GABA) content of kimchi containing the 5% GBRC solution was 3 times higher than that of controls. The total phenolic compound content (130 mg%) did not change significantly in the control group, but increased in 10 mg% increments as the GBRC concentration rose from 1 to 3 to 5%. 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical scavenging activity and superoxide radical scavenging activity also increased with the GBRC concentration, with maximum activity during the ripe stage with GBRC measured at 79 to 82% compared with controls (30 to 71 %). The nitrite scavenging activity was 10% higher with GBRC compared with controls and was highest when the pH was 1.2. These results showed that the addition of GBRC is effective in improving the function of kimchi.

• Journal of the Korean Chemical Society
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• v.65 no.5
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• pp.313-319
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• 2021

Menthol (M) is a cyclic monoterpenode and is a major component of essential oils. Menthol, along with menthol, isomenton, etc., gives taste and odor of the mint plant, and when it comes to menthol in general, L- or (-) -menthol is usually used. Included in pharmaceuticals, cosmetics and pesticides. It has antimicrobial, antibacterial, antioxidant properties. It is also known that the licorice plant (Glycyrrhiza Glabra L.) differs from other types of plants by its medicinal properties. For many years it has been used in folk medicine. Extraction of licorice root revealed up to 25% glycyrrhizinic acid (GA). Its aglycone - glycyrrhizic acid is notable for its structural similarity to the adrenal cortex hormones. Currently, GA and glycyrrhizic acid are widely used in medicine as a remedy for colds, allergies, viral diseases, tumors. The biological activity of menthol and GA-based supramolecular compounds has been poorly studied, and their effect on the functional parameters of rat liver mitochondria has been studied little. For this purpose, in our experiments, the effect of menthol (M), glycyrrhizinic acid (GA) and their supramolecular complexes obtained in different proportions on in vitro and in vivo studies on rat liver mitochondria was studied.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.271-276
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• 1993

This study was carried out to prepare anchovy based powder for instant soup packed in tea bag which can be used handily as a extractives, and to determine the taste compounds of extractives of anchovy based powder for instant soup. The anchovy based powder for instant soup was made by adding of 72% in the redried anchovy, 14% in the sea tangle, 7% in the mushroom and 7% in the katsuobushi to the total mixtures. And the anchovy based powder for instant soup was packed in tea bag. The desirable extraction time are 5 min in package in tea bag with air permeability $100\;m^3/m^2/min$ and over 20 min in package in tea bag with air permeability $65\;m^3/m^2/min$, respectively. Judging from the result of extraction rate of total nitrogen, color and sensory evaluation in extractives of anchovy based powder for instant soup extracted by optimal extraction time, the quality in extractives of instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$ was superior to those of instant soup unpacked in tea bag and of instant soup packed in tea bag of air permeability $65\;m^3/m^2/min$. The principal taste compounds of extractives of anchovy based powder for instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$ were IMP (9.26 mg/100ml in 5% solution) and free amino acids (24.30 mg/100 ml in 5% solution) such as histidine, proline, lysine and taurine. Total creatinine, betaine and TMAO were seemed to act an auxiliary role in taste of extracives of anchovy based powder for instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.448-452
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• 1997

Sensory and physical qualities and palatable compounds of cultured flounder muscle were compared with the wild ones. No differences were seen in the contents of the moisture, lipid, protein between cultured and wild dorsal muscles, however, sensory panels preferred the wild fish to cultured ones because of the texture and taste of wild fish, and they could differentiate the degree of difference in the texture and taste property distinctly. Raw meat of the wild fish was harder and more elastic than the cultured ones, however, the cultured meat was harder and drier than the wild ones once they were cooked. The results of physical properties were similar to the results of sensory evaluation. Alanine was the most abundant compound among the free amino acids which make meat palatable and followed by glutamic acid, proline, methionine, and glycine. There was no difference in total content of free amino acids between two fish muscles. ATP was the most abundant among all nucleotides and their related compounds in both fish muscles followed by IMP, ADP, AMP, however, the total content of those was greater in wild fish muscle (9.4 ${\mu}$mole/g) than in cultured fish muscle (6.7 ${\mu}$mole/g).

• Food Science and Preservation
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• v.24 no.5
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• pp.585-592
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• 2017

The purpose of this study was to prepare blueberry syrup (cheung) using fructooligosaccharide instead of the traditionally used sucrose. The sugar content, pH, and colorimetric values were measured to evaluate the quality of the prepared syrup, and the antioxidant activity and phenolic compound content were determined to assess the physiological activity of the syrup. The $L^{\ast}$ value (lightness), pH, and color were high in syrups containing a high proportion of fructooligosaccharide. The $a^{\ast}$ value (redness) was high in syrups subjected to heat treatment, and the $b^{\ast}$ value (yellowness) tended to be the opposite of the $L^{\ast}$ value. Moreover, syrups containing heat-treated fructooligosaccharide showed higher polyphenol, flavonoid, and anthocyanin contents than the unheated syrups did. The antioxidant activity of the blueberry cheung depended on the content of phenolic compounds. The highest value was obtained in the cheung prepared using a heat-treated 1:1 mixture of blended raw blueberry and fructooligosaccharide (S2). These findings suggest that our familiarity with the taste of the sweetener used influences our taste preference. It is therefore necessary to study other newly developed sweeteners apart from fructooligosaccharide to find a suitable alternative to sucrose.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.911-918
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• 2007

Korean tea leaves (Camellia sinensis var. sinensis,), which were harvested in April, were fermented for various times, and then the changes in free amino acids (glutamic acid, GABA, arginine, theanine), pH, color values, and sensory qualities were evaluated. The pH in every sample became lower as fermentation time increased. Lightness also decreased as tea fermentation increased. Furthermore, glutamic acid, GABA, and arginine contents increased, while theanine content decreased, where it presented as 69% of the non-fermented tea leaves. GABA, a hypotensive compound, increased in the fermented tea leaves according to the degree of fermentation and hand rolling times. In terms of the theanine relaxation effect as well as taste, a shorter fermentation time is required, and for a hypotensive effect of GABA, fermentation needs to be increased. For the sensory evaluation, the preferred blend of taste and flavor was highest in the S8 tea sample.

• Food Science and Preservation
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• v.20 no.2
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• pp.166-172
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• 2013

The effect of phytoncide solution treatment on the browning and quality of fresh-cut iceberg lettuce during storage was studied. The treatments were applied as four solutions adjusted at $10^{\circ}C$: distilled water (DW) as the control; edible ethanol (EE); 1% (v/v) phytoncide essential oil from pine needle diluted with distilled water (DP); and 1% (v/v) phytoncide essential oil diluted with edible ethanol (EP). Fresh-cut lettuce was dipped in each solution for 60 sec, was rinsed with distilled water, was packaged with an OPP film bag, and was then stored at $4^{\circ}C$ for 12 days. The EP group had a significantly high level of total soluble solids, titratable acidity, and carbon dioxide, and low total bacteria counts, pH, and oxygen. The sensory score of color in the EP group recorded a high value, but the EE and EP groups recorded low scores in aroma and taste during the storage period. Alcohol and phytoncide were vaporized by opening the package for two hours, and the score of the aroma and taste of EP showed no differences from those of the other groups. Based on the above results, it was determined that the phytoncide essential oil diluted in edible alcohol with 1% solution inhibited the browning of and microbial growth in fresh-cut lettuce, and will be a useful natural compound in maintaining the quality of fresh-cut produce.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1345-1349
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• 1998

The flavor constituents and functionality of small kingfish were studied as affected by two stage enzyme hydrolysis (TSEH). Total free amino acid contents in water extract, autolytic extract and TSEH of small kingfish were 541.3 mg%, 8,245.3 mg% and 6,636.6 mg%, respectively. Major free amino acids in TSEH were hydroxyproline, glutamic acid, proline, leucine, phenylalanine, lysine, arginine. As for nucleotides and other bases, IMP, TMAO and total creatinine were principal components in TSEH. And the major inorganic ions in TSEH were Na, K, P, Cl and $PO_{4}$. Also TSEH of small kingfish revealed very higher Angiotensin-I converting enzyme inhibition effect than those of water and autolytic extract.