• Food Science and Preservation
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• v.14 no.6
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• pp.669-675
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• 2007

Quality characteristics of Kwamaegi (semi-dried saury) prepared by treatment of chitosan-ascorbate (CA) and vacuum drying at $40{\sim}60^{\circ}C$(VDK), and the effect of the Kwamaegi on serum lipid profiles and anti-oxidation-related enzyme activity in rats fed high fat diets were investigated. The preparation periods were $4.5{\sim}8.3$ hr in VDK, while naturally dried Kwamaegi (NDK) took 360480 hr. Total microbe contents of VDK and NDK were $0.2{\sim}0.5$ and 8.2 log CFU/g, respectively. There was no significant difference in amino-nitrogen content. Compared with NDK, the acid and peroxide value, and fishy flavor of VDK40 (dried at $40^{\circ}C$) were significantly lower, and the texture, color and overall acceptability were higher. In animal experiments, weight gain, content of LDL-cholesterol and lipid peroxide, activities of total (T) and O type (O) xanthine oxidase, and the O/T ratio (%) were significantly lower in the VDK40 diet group than in the NDK diet group. The content of HDL-cholesterol in the VDK40 diet group was higher than in the NDK diet group. These results suggest that preparing CA-treated Kwamaegi with vacuum-drying at $40^{\circ}C$ can be applied throughout the year, and may shorten preparation time and improve its microbiological safety and nutritional values.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.671-679
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• 2003

Effects of sun-dried, refined, seaweed, and bamboo salts on the quality of kochujang were studied by measuring enzymatic, microbial, and physicochemical characteristics of kochujang during 12 weeks of fermentation. Yeast count was low in the bamboo-salt kochujang, whereas that of aerobic bacteria was low in the seaweed-salt kochujang. Acid protease activity was high in the bamboo-salt kochujang, whereas amylase activity did not show any remarkable difference. Color change was lowest in the bamboo-salt kochujang. Water activities of all kochujangs decreased during fermentation with the lowest shown in the refined-salt kochujang. Consistency of seaweed-salt kochujang was the highest. Total sugar content was higher, whereas ORP was lower in the seaweed- and bamboo-salt kochujangs. Titratable acidity changed slightly in the bamboo-salt kochujang. Reducing sugar content was the lowest, whereas ethanol content was the highest in the refined-salt kochujang. Amino and ammonia nitrogen contents of kochujangs increased up to the middle of fermentation period then decreased with lower changes observed in the sun-dried and refined-salt kochujangs. Results of sensory evaluation indicated that the bamboo-salt kochujang was more acceptable than the sun-dried salt kochujang in taste, color, and overall acceptabilities.

• Korean Journal of Agricultural Science
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• v.8 no.1
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• pp.117-125
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• 1981

The changes in chemical compositions of chestnuts were tested during processing in order to elucidate the effects of heat treatments such as boiling, steaming and roasting on the flesh compositions. The results obtained were as follows. 1. The chemical compositions of raw chestnuts were: moisture, 59-61%; total sugar, 24-27%; crude fat, 0.3%; crude fiber, 0.6-0.9%; ash, 1.0%; amino nitrogen, 0.3%; vitamin C, 20-22 mg%; and tannin, 40-48%. 2. The moisture contents were increased to 63.8% by the boiling and to 70.27% by the peeling and boiling from 59.41% of raw ones respectively, whereas decreased to 54.11% by the roasting. 3. Contents of crude protein were decreased to 8.04% by the peeling and boiling procedure from 8.72% of raw ones, and those of amino nitrogen also revealed a decreasing tendency by the heat treatments. However, no significant change was observed in crude fat content. 4. Total sugar contents were decreased by the peeling and boiling procedure approximately 3.0%, whereas reducing sugars were increased 2 to 3 times in the all treatments. 5. Vitamin C contents were decreased 72.0 to 78.0 % by the boiling procedure, 64.2% by the steaming, 51. 6% by the roasting as compared with the raw ones. Tannin contents were increased 11.0% by the boiling, and 46.0% by the roasting respectively, whereas decreased 22.0% by the peeling and boiling procedure. 6. The color was changed to brown with different degree, during the boiling, steaming and roasting procedure. The 0.1% solution of alum appeared to be effective in reducing the browning reaction during the heat treatments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.333-338
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• 2008

The tea has traditionally been used as a foodstuff by unique flavor, however recently not only the diversity of consumer demands but also the public interest in unique favorite and functional aspects have increased. It has been also reported that the main components contained in the leaves of tea (Camellia sinensis) include total nitrogen, free amino acids, polyphenols, and fiber, of which catechin has powerful bioactive effect such as anti-cancer, anti-aging, and anti-diabetic. (-)-Epigallocatechin gallate (EGCG) which is a major phenolic constituent of green tea extract has received considerable attention for a variety of important bioactivities. This study was carried out to obtain useful information for tea breeding programs, and to investigate the concentration of quality and functional related components in Korean indigenous tea germplasms. Korean indigenous tea lines were classified into three groups of sprout time, i.e, early, medium and late sprout time, and the ratio were 20%, 43% and 37%, respectively. There was a difference in characteristics among these Korean indigenous tea lines, leaf width of those ranged from 19.8 to 75 mm, leaf length was 35.5-160.0 mm, and leaf area was $660-8,400\;mm^2$. Experimental data on chlorophyll content (SPAD value) of Korean indigenous tea genetic resources ranged from 51.3 to 82.3. The concentrations of the total nitrogen, total free amino acids, and theanine were ranged 4.18-6.07%, 2.87-4.58%, and 1.64-2.66%, respectively. Also, catechin concentration showed from 11.54 to 15.07%, and concentration of caffeine was 2.82-4.23%. These results indicated indicated that it is possible to select elite lines with high concentration of quality related components and low concentration of caffeine from Korean domestic tea germplasms.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.301-308
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• 1982

Chungkook-jang Koji was fermented with rice straw at $40^{\circ}C\;and\;50^{\circ}C$ for 72 hours. The changes of proximate composition, pH, titrable acidity, nitrogen compounds, protease activity and free-amino acids during the fermentation were investigated. Moisture, lipid and protein contents remained essentially unchanged during the fermentation. The pH was gradually increased from 6.4 to 7.46 and 7.82 at $40^{\circ}C\;and\;50^{\circ}C$, respectively, after 72 hour fermentation. Amino type and water soluble nitrogen increased as fermentation progressed. however, the former slightly decreased after 60 hour fermentation. Chungkook-jang fermented at $40^{\circ}C$ showed somewhat higher protease activity than $50^{\circ}C$. However, protease activity at both fermentation temperatures showed the same trend; that is, it increased until 48 hour fermentation and thereafter decrease. Free amino acid content of Chung-kook-jang after 72 hour fermentation at $40^{\circ}C$ was 6 times greater than that of the steamed soybean, while it was 2.5 times greater at $50^{\circ}C$. Based on these results. it seems that the optimum fermentation conditions for Chungkook-jang were $40^{\circ}C$ and 72 hours.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.444-450
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• 2001

Kochujang, fermented hot pepper paste, was treated with combined high hydrostatic pressure and heat. Viable cell counts and chemical compositions of Kochujang were determined as a function of high pressure processing conditions such as temperature, pressure and time, and during storage for 120 days at $37^{\circ}C$. Viable cell counts were decreased with the increase of temperature, pressure and time. Viable cell counts in the treated Kochujang were decreased up to $0{\sim}3$ log cycle with the temperature of $49{\sim}73^{\circ}C$, $0{\sim}3$ log cycle with the pressure of $380{\sim}680\;MPa$, and $2{\sim}5$ log cycle with the time of $10{\sim}70\;min$, compared with the untreated. pH, titratable acidity, amino nitrogen, reducing sugar and ethanol content in the treated Kochujang were comparable to the untreated regardless of the treatment condition. Hunter L, a and b values in the treated Kochujang were higher than those of the untreated. Viable cell counts were decreased with the increase of the storage period at $37^{\circ}C$. Viable cell counts in Kochujang treated at 380 MPa/30 min were decreased up to 2 log cycle from $1.8{\times}10^6\;to\;1.94{\times}10^4\;CFU/g$ after 120 days of storage, while those at 680 MPa/70 min were not detected after 60 days from the initial stage of $4.00{\times}10^1\;CFU/g$. pH, amino nitrogen and ethanol content were decreased, and titratable acidity were increased significantly as the increase of the storage period. Hunter L, a and b values also decreased significantly. The changes in physicochemical properties of Kochujang treated at 680 MPa/70 min were greater than those at 380 MPa/30 min.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.4
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• pp.525-534
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• 2001

A total of 120 pigs were used to investigate the effects of yucca extracts on the growth performance, nutrient digestibility, nutrient excretion and carcass characteristics of finishing pigs fed different levels of dietary protein. Pigs were allotted into $2{\times}3$ factorial design by the supplementation of yucca extracts (YE, 0 and 120 mg/kg) and 3 levels of dietary protein (14, 16, 18% for early finisher and 12, 14, 16% for late finisher for low, medium and high protein diet, respectively). During the early finishing period (51~76 kg BW), no significant difference was found in growth performance regardless of the YE supplementation or dietary protein levels. Growth performance of late finishing pigs (76~101 kg BW) was also not significantly different among treatments. However, ADG of pigs fed YE diet was significantly improved (p<0.05) regardless of the dietary protein levels. For the overall period (51~101 kg BW), although adding YE to the diet and elevating the protein level showed better ADG, there were no significant differences on growth performance among treatments. Early finishers showed significantly higher crude protein, crude ash and crude fat digestibilities when they were fed diets supplemented with YE. Digestibilities of amino acids were not affected by YE. Late finishers did not show any significant differences in proximate nutrient digestibilities regardless of YE supplementation or dietary protein levels. YE tended to slightly improve the CP digestibility, however no significant difference was found with increased dietary protein levels. There was no significant difference in amino acid digestibilities with YE supplementation or dietary CP levels during the late finishing period. Dry matter (DM) and nitrogen (N) excretion in feces did not show any significant difference among treatments. Early finishing pigs also did not respond to the inclusion of YE or dietary protein levels (p<0.05). Fecal N excretion of early finishing pigs seemed to be lowered in pigs fed YE. Pigs fed medium dietary protein diet tended to excrete a higher amount of N during the early finishing period, but not statistically different. A slight increase in fecal N excretion was found with the increased level of dietary protein during the late finishing period. For ammonia nitrogen excretion, although there was no significance, the NH3-N content tended to be increased by the increased dietary protein levels and with YE supplementation. The NH3-N content in manure increased by 24.5% with YE supplementation. There were no significant differences in carcass weight, backfat thickness, carcass grade and loin eye area among treatments. However, pigs fed non-YE with low protein diet showed a significantly (p<0.05) low carcass ratio among treatments and there was significant (p<0.05) difference between the YE-added treatment and non YE treatment in carcass ratio. As for the feed cost, the cost of feeding high level protein was higher than that of medium level protein by 5% and low level protein by 9% (p<0.05). Therefore, based on this study, it could be concluded that environmentally friendly agents might play a role to some extent in finishing pigs from the aspect of pollution control, and that more than 14 and 12% of dietary protein for early finishing and late finishing pigs respectively do not necessarily guarantee high growth performance.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.243-254
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• 2012

The purpose of this study is to rapidly produce a sauce using paprika powder in a short period. The test results of moisture content, pH, salinity, color, texture, reducing sugar, amino-nitrogen, and sensory testing are as follows. The water content of sauce (CON) using paprika powder was 26.31%, whereas 31.58% in SP1, 31.40% in SP2, 30.84% in SP3, and 24.08% in SP4. pH value increased with increasing paprika powder (P<0.001). Salinity ranged from 4.87% to 5.22%, which showed a lower value than that of a former study. In terms of color, SP3 showed the highest L value (28.01), and CON showed the highest a and b values (P<0.001). In textural properties, CON showed the highest hardness of 205.50, whereas SP3 showed the lowest hardness of 106.53. Contrary to the results for hardenss (ED:?) CON showed the lowest adhesiveness which was -704.17, SP3 showed the highest value which was -348.93. SP1, and SP2 showed the highest reducing sugar value (P<0.001), and SP1 and SP4 showed the highest and lowest values of amino-nitrogen, respectively (P<0.001). In the results of sensory tesating, SP2 showed the greatest appearance and flavor, but was not found to be significantly different to any of the others. CON, SP1 and SP2 showed the best texture(P<0.05) and SP2 showed the best interest among them with no significant difference. According to these results, SP2 made with 200g of paprika powder, 150g of soy powder, 600g of grain syrup, 500g of water, and 75g of salt showed the highest sensory interest value and was determined to be the most suitable for making the paprika sauce.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.242-256
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• 1997

The physico-chemical properties and possible biological functionalities of commercially available persimmon vinegars were studied by measuring the specific gravity, turbidity, color, pH, total acidity, reducing sugars, alcohols, total nitrogen content, composition of organic acids and amino acids, soluble pectin, soluble tannin, ascorbic acid, acetoinic compounds, electron donating ability and nitrite scavenging ability. Persimmon vinegars had low specific gravity(1.005-1.0200) and lightness(40.03-54.95), but high turbidity (0.12-1.311, absorptivity at 660 nm), redness(1.65--0.64) and yellowness(4.54-8.14) compared to the other fruit vinegars reported. These physical property values of the individiual product differed greatly. The tested persimmon vinegars contained relatively large amount of reducing sugars(0.45-0.84%, w/v), alcohol(0.16-3.18%, w/v) and total nitrogen(30-60mg%, w/v). The pH values (average 3.70) of products were relatively high and the total acidities(average 3.04%, w/v) of the tested persimmon vinegars were lower than that($TA{\geq}4.0%$) specified by the Korean standard for fruit vinegar. The major organic acids identified in the tested products were acetic acid(17.6-72.9%) and lactic acid(25.1-74.1%). The acetic acid contents in the 5 products out of the 7 tested persimmon vinegars were lower than lactic acid content. The level of free amino acids of the persimmon vinegars were relatively high in arginine, methionine and threonine. Persimmon vinegars contained relatively large amount of soluble pectin(91.8-232.8mg%, w/v), soluble tannin(49.0-161.7mg%, w/v) and ascorbic acid(12.8-29.6mg%, w/v). The persimmon vinegars were high in 2,3-butanediol (average 166.90ppm) and acetoin(average 111.43ppm). The persimmon vinegars showed strong electron donating ability and nitrite scavenging ability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.191-200
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• 1979

For the use of antarctic krill as a fond protein source its compositional characteristics were investigated as the first part of the work includes other subjects such as processing of drill paste, concentrates, and fermented or seasoned product. In general composition of fresh frozen and preboiled frozen krill on board, the contents of crude fat and free amino nitrogen were higher in the former than in the latter which contained a high amount of ash. VBN was rather high as much as 37.6 and $26.4\;mg\%$ in both fresh frozen and preboiled krill. The pH of drill homogenates was 7.1 to 7.2 in both cases. Such a low pH might be attributed to a long term storage and temperature fluctuations during frequent transshipping. The amino acid competition of fresh frozen krill meat showed relatively high amount of glutamic acid, aspartic acid, lysine, proline, and leucine while methionine, histidine, serine, tyrosine, and phenylalanine were lower. Among the essential amino acids lysine and leucine were higher and methionine was lower. In tile composition of free amino acid proline, lysing, arginine, and alanine were higher comparatively to the contents of histidine, aspartic acid, serine, and threonine. It is noteworthy for nutritional qualification that tile essential amino acids particularly as lysine were abundant similarly to that of fishes. Heavy metal contents of krill meat 0.039 to 0.048 ppm as Hg, 0.06 to 0.11 ppm as Pb, less than 0.32 ppm as Zn, 0.008 to 0.012 ppm as Cd, 0.61 to 0.68 ppm as Fe, 0.87 to 1.37 ppm as Cu, and nondetective as Cr. A high Cu content seems to be resulted by tile blood pigment of crustacea. The ratio,1 of edible portion to non-edible portion were 37:63 in fresh frozen and 42:58 in preboiled frozen krill respectively. Release of drip after thawing was more in fresh frozen than in preboiled frozen drill marking $36\%$ and $24\%$ of both respectively.