• Food Science and Preservation
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• v.19 no.6
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• pp.882-892
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• 2012

This study was conducted to investigate several indicators of fruit maturity, and expert sensory evaluation was done to determine the most appropriate maturity time for the new Korea grape cultivar 'doonuri' for high quality winemaking. The grape component changed dramatically during ripening, after veraison. Considerable drops in berry firmness (<0.60 kgf/$cm^2$) and titratable acidity (<0.66%) were found at the ripening stage while the soluble solid content significantly increased in the ripening process. Most of the organic acids contained were tartaric and malic acid. The malic acid content was about twice the tartaric acid content in the fruit-growing period but was less than the tartaric acid content in the maturity period. The total anthocyanin and polyphenol contents increased sharply after veraison. In particular, the total anthocyanin and polyphenol contents reached their maximum levels when the acidity was 0.55%, and after that, there was almost no change. Correlations between anthocyanin accumulation and several factors were found in sugar 0.7811 (p<0.05), pH 0.9315 (p<0.05), and Brix/acid ratio 0.9409 (p<0.05). $Brix{\times}pH^2$ and brix/acid ratio were used as indicators of the proper maturation of the grapes when the acidity was 0.53 to 0.55%, and at sugar 17 Brix. When surveyed, the quality characteristics and sensory evaluation of the wine made using the latest harvested grapes showed the most reliable sourness. The color, aroma, and overall harmony of the wine, however, were evaluated to be the best when the wine acidity was about 0.60% or when the grape acidity was below 0.55%.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.648-656
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• 2021

This study analyzed the physicochemical properties of Danyangju and Iyangju fermented using uncooked germinated brown rice. Total bacteria and yeast from Danyangju and Iyangju showed the maximal value on day 1 of fermentation, but their numbers decreased by the seventh day. On the seventh day, the total bacteria were higher in Iyangju than in Danyangju, but yeast was the lowest in Iyangju. Both Danyangju and Iyangju showed decreased whiteness in color, whereas redness and yellowness increased with fermentation. Sugar contents, reducing sugar, acidity, alcohol, and polyphenol contents increased during fermentation in both Danyangju and Iyangju; this increase was higher in Iyangju than in Danyangju. Iyangju and Danyangju showed gradual increases in α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity until day 5. The γ-aminobutyric acid (GABA) content increased with fermentation in Iyangju and Danyangju, and Iyangju showed over 10-fold increase after fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.928-934
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• 2011

Nutritional compositions of acorn crude starch were analyzed according to country of origin, especially the mineral and sugar contents. Regarding the three kinds of starch of domestic (South Korea, KAS), Chinese (CAS), and North Korea (NAS) origins in the Korean market, NAS had the lowest moisture content as well as the highest contents of crude protein, crude fat, and carbohydrate. Regarding mineral contents, NAS contained the highest amounts of magnesium, calcium, sodium, potassium, and phosphorous, whereas CAS contained the highest iron and zinc contents. There were no significant differences in acidity and pH. Analysis of the monosaccharide contents of the starches showed that glucose was the highest in KAS while sucrose was the highest in CAS. The Hunter color L value was the lowest in NAS, whereas a and b values were the lowest in CAS. Total phenolic content was the highest in NAS. NAS had the highest DPPH and hydroxyl radical scavenging activities ($IC_{50}$: 47.0 mg/mL for DPPH, 0.038 mg/mL for hydroxyl) whereas KAS had similar DPPH ($IC_{50}$: 73.7 mg/mL for CAS, 86.8 mg/mL for KAS) and hydroxyl radical activities ($IC_{50}$: 0.041 mg/mL for CAS, 0.044 mg/mL for KAS) as compared to CAS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.24-32
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• 1984

In order to process instant foods which hold appropriate moisture contents and soft texture, four kinds of retort pouched seasoned-oyster products were prepared as control, seasoned products, solid smoked and liquid smoked product after seasoning and their processing conditions and quality stability during 100 days of storage were investigated. The optimum processing conditions of retort pouched seasoned-oyster product were as follows ; namely, raw oyster was seasoned at $105^{\circ}C$ for 10 min with seasoning solution prepared from sugar, sorbitol, salt, monosodium glutamate and 5'-ribonucleotide and then dipped for 30 seconds in Smoke-EZ solution(Alpha Foods Co., Ltd.) after predried for 30 min in hot-air drier. After. smoking, the seasoned and liquid smoked oyster was dried at $40-42^{\circ}C$ for 2.5 hours, vacuum packed in plastic film bag, and sterilized in a hot water circulating retort at $120^{\circ}C$ for 16 min. Comparing their quality before and after sterilization, TBA value of all the products after sterilization slightly decreased and among texture profiles hardness, toughness and chewiness slightly decreased, while elasticity and cohesiveness were rarely changed. Color value (a value) of the product treated with solid smoke or liquid smoke increased after sterilization. During storage pH, VBM and water activity of all products changed little and TBA values of the solid smoked product and liquid smoked one were lower than that of the others. Viable cell count was negative and texture changed little during storage. As for color difference during storage, green meat appeared on the surface of control and seasoned product after 15 days storage, while the masking of green meat could achieved by solid and liquid smoking treatment. And liquid smelling treatment was more effective than solid smoking. As a conclusion, retort pouched seasoned-oyster product treated with liquid smoke kept their good quality during 100 days storage and it seemed to be consumed as one of the instant foods which hold appropriate moisture contents and soft texture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.316-324
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• 1985

Vacuum-packed and seasoned smoked-dried products of red squid, Ommastrephes bartrami, caught in the Northern Pacific Ocean, were prepared and stored at room temperature for 90 days to test their keeping quality. Defrosted squids were eviscerated, skinned, and cut. The mantle meats were flavored with seasoning powders prepared from sugar, sorbitol, salt, monosodium glutamate, or smoke flavor (Smoke-EZ, Alpha Foods Co., Ltd.). After seasoning, the mantle meats were dried at $45^{\circ}C$ for 7 hours, vacuum packed in plastic film bags, and pasteurized in water at $95^{\circ}C$ for 30 minutes. Three kinds of products were prepared : control products (seasoned-dried), solid smoked seasoned-dried and liquid smoked seasoned-dried. The moisture level, water activity, color value (L, a and b value), texture, and viable cell counts of bacteria in these products were determined during storage at room temperature, $5^{\circ}C\;and\;35^{\circ}C$, respectively. The results showed that the products could be preserved at good condition for 90 days though they developed pale brown color during storage. The contents of free amino acids, nucleotides and their related compounds, and the compositions of fatty acids of raw squid and smoked products were analysed. In the amino acids, arginine, taurine, glycine and proline were abundant in raw and smoked products. The contents of hypoxanthine of raw and smoked products were higher than the other nucleotides and their related compounds. In fatty acid compositions of raw and smoked products, the dominant fatty acids were docosahexaenoic acid (22:6), hexadecanoic acid(16:0) and eicosapentaenoic acid (22:5).

• Food Science and Preservation
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• v.23 no.6
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• pp.804-810
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• 2016

This study aimed to compare the quality characteristics of developed rice Jochung (E) with those of commercial-rice Jochung (A, B, C, and D). The total soluble solid, reducing sugar, and dextrose equivalent of developed rice Jochung were $80^{\circ}Brix$, 44.53%, and 56.94%, respectively. The pH and titrable acidity were 6.25 and 0.19%, respectively. The color difference value (${\Delta}E$) of developed rice Jochung was 74.42, which was significantly lower than the other samples investigated. The light transmittance and total polyphenol contents of developed rice Jochung were 56.4%T and 108.23 mg GAE/100 g, respectively. The adhesiveness values of various commercial-rice Jochung products were 29.0~66.0 sec, while that of developed-rice Jochung was 61 sec, showing good textural properties for use in manufacturing Hangwa, a Korean traditional cookie. The electron-donating values of various rice Jochung were 20.4~50.3%, among which the developed-rice Jochung showed the highest value. The reducing powers of various rice Jochung products were 0.44~0.72, while that of the developed product was 0.72, which was significantly higher than the other values. Sensory evaluation revealed that the color scores of developed- and commercial-rice Jochung products were 6.70~6.80. Flavor scores of rice Jochung products ranged from 6.00 to 7.00. Taste and mouth feeling scores of developed-rice Jochung did not significantly differ from those of commercial Jochung products. Compared to commercial-rice Jochung products, developed-rice Jochung made with malt extract exhibited high polyphenols content. However, there were no significant differences in the overall acceptability scores between commercial-rice Jochung products and the developed product. The developed-rice Jochung analyzed in this study may be useful as a traditional sweetener for various Hangwa products as a substitute for corn syrup or Jochung.

• Food Science and Preservation
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• v.17 no.1
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• pp.58-65
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• 2010

We investigated the effect of Chun ma (Gastrodiae rhizoma) concentrated extract on the quality of mixed beverages. Chun ma beverages prepared using different concentrated extracts were divided into four groups: GCE 5 ($5^{\circ}$ Brix concentrated extracts) GCE 10 ($10^{\circ}$ Brix concentrated extracts) GCE 15 ($15^{\circ}$ Brix concentrated extracts) and GCE 20 ($20^{\circ}$ Brix concentrated extracts). The pH values ranged from a low of 4.37 in GCE 5 to a high of 4.68 in GCE 20. Soluble solid levels in GCE 20 ($19.6^{\circ}$ Brix) were higher than in the other samples. The b (yellowness) scores and the total phenolic contents of all samples increased with increasing extract concentration. The highest total phenolic contents were seen in GCE 20 samples at 232.23 mg%. Samples did not differ markedly in antiradical activity (75.07-76.00% DPPH inhibition). Free sugar levels in GCE 20 samples and organic acid concentrations of GCE 15 samples were higher than those of other preparations. Free amino acid and mineral contents of all samples increased with increasing extract concentration. The levels of free amino acids were in the order Glu > Gly > Ser > Arg > Hylys, and the Glu content was 249.15 ug/100 g for GCE-20 samples and 61 ug/100 g in GCE-5 products. The mineral contents of all samples were in the order K > Na > Mg > Ca. Higher scores for color, flavor, and overall acceptability were found in GCE 5 products compared with other extracts. These results indicate that Chun ma beverage can be prepared in various ways, as commercially desired, with reference to the above characteristics of Chun ma materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1402-1408
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• 2012

Mulberry pomace, a by-product obtained from mulberry juice, has not been utilized as food. In this study, antioxidant activities, proximate composition and physiochemical characteristics of mulberry pomace were evaluated and compared with those of mulberry fruit or mulberry concentrate. Mulberry fruit was pressed and filtered. The filtrate and residue were used as mulberry juice and mulberry pomace, respectively. Mulberry juice was evaporated, after which a concentrate ($24.7^{\circ}Brix$) was obtained. Moisture contents of mulberry concentrate, freeze-dried mulberry, and pomace were 68.7%, 6.03%, and 7.32%, respectively. Reducing sugar contents were 45.7% in freeze-dried mulberry, 24.5% in pomace, and 30.9% in mulberry concentrate. The pH and acidity of the three samples ranged from 5.80~5.92 and, 0.035~0.080%, respectively. Carbohydrate and crude ash contents were the highest in mulberry fruit, whereas crude protein, fat, and fiber contents were the highest in pomace. Redness of the Hunter color system was 4.7 in mulberry and 4.3 in pomace. Total phenolic content was the highest in mulberry fruit, whereas total flavonoid content was the highest in pomace. Antioxidant activities (DPPH, hydroxyl, and ABTS radical scavenging activities) were enhanced in the order of mulberry fruit> pomace> mulberry concentrate. Especially, antioxidant activities, such as DPPH and hydroxyl radical scavenging activities, of mulberry pomace were similar with those of mulberry fruit. Based on these results, freeze-dried mulberry pomace may be considered as a functional as well as an additive material for food processing.

• Korean journal of food and cookery science
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• v.30 no.4
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• pp.402-411
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• 2014

This study investigated the quality characteristics of tea leaf pickle with different pickling solutions. Blanched tea leaf at $100^{\circ}C$ for 3 min was pickled using pickling solutions (mixture of water, soy sauce, sugar and vinegar) with different vinegar contents (10, 20, 30 and 40%, v/v). and stored for 30 days at $4^{\circ}C$. The color values, hardness, pH, total acidity, sensory evaluation, antioxidant compound contents, DPPH radical scavenging and ABTS radical scavenging of the pickled tea leaf during storage were determined. The pH of tea leaf pickles decreased consistently and total acidity was increased during storage. The L-value of tea leaf pickles was decreased and the a-value was increased significantly during storage; however, the b-value had no significant changes (p<0.05). The hardness of the tea leaf pickles decreased consistently during storage. On the sensory evaluation, the highest score of overall acceptance was presented to the tea leaf pickle using a 20% vinegar pickling solution stored for 20 days. The antioxidant compound contents and antioxidant activity consistently decreased during storage; further, the experimental group of vinegar with 20% content tea leaf pickle displayed the lowest antioxidant compound content and antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.12 no.4
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• pp.313-323
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• 1980

The objective of this experiment was to improve the quality and shortening the aging time of Kochujang by adding mixed starter cultures of yeast strains. Kochujangs were mashed during the summer season with mixed starter cultures of Saccharomyces rouxii, Torulopsis versatilis and Torulopsis etchellsii. Enzyme activities and chemical composition of the Kochujang were determined during the period of aging and their organoleptic values were tested. The maximum activities of liquefying amylase and saccharogenic amylase in the Kochujang were obtained during 20 to 60 days and 20 to 30 days after mashing respectively. The acidic protease activity was reached maximum during 20 to 40 days. All enzyme activities were decreased markedly during the final stage of aging period. Among mixed starter cultures tested, mixed culture of T. versatilis and T. etchellsii shows the highest liquefying and saccharogenic amylase activities. Ethyl alcohol contents in 10 days after mashing were highest in the Kochujang with S. rouxii and T. versatilis, followed in order of S. rouxii and T. etchellsii mixture, T. versatilis and T. etchellsii mixture and control without addition of yeast. But the contents in all sample became similar after 20 days with the level of 2.3 to 2.8% and then decreased gradually. The level of reducing sugar contents was markedly increased during the first 10 days, especially in the batches of T. versatilis and T. etchellsii mixture and control. However, the concentration became similar in all samples after 40 days. The contents of amino nitrogen were increased markedly during the first 10 days then slowly up to 90 days. The rate was high in the Kochujang with T. versatilis and T. etchellsii when compared with others. The organoleptic values of all Kochujang made with addition of yeast starter cultures were superior to control, especially in flavor, taste and color. The Kochujang with T. versatilis and T. etchellsii marked the highest value. The data obtained from this experiment suggests that the quality of Kochujang could be improved by using starter culture of suitable yeast strains according to product characteristics and aging time.