• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.458-463
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• 1995

A curd yogurt was prepared from milk added with skim milk powder or egg white powder(EWP). The effects of EWP addition on growth and acid production by lactic acid bacteria in milk were studied. The effects of EWP addition on quality of curd yogurt in point of apparent viscosity, sensory property and volatile aroma compounds were also investigated. Addition of PAT markedly stimulated acid production by lactic acid bacteria and stimulating effect of EWP on acid production was proportional to the amount of addition. Apparent viscosity of curd yogurt added with EWP was generally higher than that of control. Curd yogurt fermented with L. acidophilus showed thixotropic characteristics. Sensory property of curd yogurt added with EWP was evaluated as better than reference sample and sample added with EWP at 2% level was evaluated as better than other samples. Acetone, ethanol, diacetyl, butanol and acetoin were detected by gas chromatographic analysis.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.543-548
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• 1990

Volatile components of fresh apricot (Prunus armeniaca var. ansu Max.) were isolated by simultaneous distillation-extraction at two different pH values of 3.1 and 7.0 and by headspace trapping method. The volatiles were analyzed by GC and GC-MS. A total of 80 components were identified in the three aroma concentrates, including 9 naphthalene derivatives that were not previously reported in apricot. Of components identified in native pH (3.1) sample, the major components were aliphatic $C_6$ aldehydes and alcohols, monoterpene alcohols, benzyl alcohol, ${\beta}-phenylethyl$ alcohol and naphthalene derivatives, while those in neutral pH(7.0) sample and headspace volatiles were aliphatic $C_6$ aldehydes and alcohols. Simultaneous distillation-extraction at pH 3.1 was significantly increased the concentration of n-hexanal, trans-2-hexenal, cis-3-hexen-1-ol, linalool oxide, linalool, ${\alpha}-terpineol$, nerol, geraniol, benzyl alcohol, ${\beta}-phenylethyl$ alcohol and naphthalene derivatives. These results demonstrate that above the components are present in glycosidically bound forms in apricot.

• Food Science and Preservation
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• v.10 no.4
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• pp.488-492
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• 2003

This study was analyzed to the components of leaf teas produced by manufature methods for which estimated food and nutritional values of Lindera obtusiloba loaves growed in Korea and had unique taste and aroma. There were identified to four kinds of free sugars in Lindera obtusiloba leaf teas and its content was the highest in the roasted tea among others. The contents of glutamic acid, aspartic acid, asparagine, and glycine were remarkably higher than other amino acids. The contentsof free amino acid in the leased tea and the androasted tea after steaming wase. 6 mg/100g had 101.5 mg/100g, respectively,had especially higher than in the others. Among the amino acid derivativer, phosphoserine, ${\alpha}$-aminobutyric acid, ${\beta}$-aminobutvic acid, and anserine contents were especially higher than others, but were not significantly difference by the manufacturing process. The volatile organic acids were composed acetic, propionic and butyric acid, and the nenvolatility organic acid were composed citric, oxalic, levulinic glutaric, lactic and pyroglutamic acid.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.346-354
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• 1987

The voflatile fraction from Korean mandarin (Citrus reticula) and valencia orange essence oil were analyzed by capillary gas chromatography and the separated components were identified from their retention time and mass pectrum. The essence oil were extracted with methylene chloride after steam distillation. The major volatile constituents of mandarin and sweet orange was limonene which accounted for 68% of total volatiles in mandarin and 87% in sweet orange. The 31 components identified from mandarin include 11 hydrocarbones, 1 ester, 10 alcohols, 4 aldehydes, 5 miscellaneous. The following 37 components were identified in sweet orange; 12 hydrocarbones, 1 ester, 11 alcohols, 8 aldehydes, 5 misecellaneous. Mandarin contained more octanal, ${\alpha}-terpinene$, terpineol, styrene, dcitronellol, citronellal, citral and farnesol while orange included more sweet orange, myrcene, ${\beta}-pinene$, linallol, decanol, ${\beta}-copaene$, elemene, ${\beta}-cadinene$, valencene.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.361-365
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• 1987

Experiments were carried out to study physico-chemical properties of citron and its products (Yu Ja cha). In addition, citron essence oil were analyzed by capillary gas chromatogaphy and the separated components were identified from their retention time and mass spectrum. The physicochemical properties as follows; soluble solid $8.8^{\circ}\;Bx$, acidity 2.1%, ratio of sugar and acid 4.2. Citron contained sucrose of 0.93%, glucose of 1.0% fructose of 1.17%. The following 28 components were identified in citron. The major volatile constituents of citron was limonene which accounted for 72.4% of total volatiles. Rest of the important compounds were ${\alpha}-pinene$, sabinene, myrcene, terpinene, terpinolene, ${\alpha}-copaene$, iso-caryophy-llene, ${\beta}-selinene$ and ${\alpha}-elemene$.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.1078-1094
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• 2021

This research investigated the physio-chemical and microbial quality characteristics of dry fermented sausage from selected Pediococcus strains: P. acidiliactici (PE1) and P. pentosaceus (PE2) as compared to commercial starter culture (COS) during fermentation and ripening. Treatments showed no substantial variation (p<0.05) in water activity (a_w) values across the study period. PE1 and PE2 treatments exhibited similar (p>0.05) pH values and presented remarkable (p<0.05) lower volatile basic nitrogen (VBN) and thiobarbituric acid reactive (TBARS) content than COS treatment throughout the ripening period. However, the pH values in COS batch were considerably lower than others. PE1 samples presented a significant highest (p<0.05) counts both in lactic acid bacteria (LAB) and total plate count (TPC) than COS and PE2 treatments at 7 days fermentation, and it resulted in a similar and higher TPC count as COS after the ripening period. After the ripening process, treatments are ordered based on LAB counts as follows: COS>PE1>PE2. All batches presented similar redness and yellowness attributes since the 7 days of fermentation and in lightness across the study period. Treatments were similar (p>0.05) in springiness and chewiness traits across the study period and in hardness characteristics in the ripened products. Cohesiveness was higher in PE1 and COS batches. No variation (p>0.05) in aroma and sourness sensory attributes of treatments. The color attribute was highest (p<0.05) in PE1 and PE2 treatments and PE1 had the highest overall acceptability. The overall outstanding merit exhibited by PE1 can be utilized in the commercial production of high-quality dry fermented sausage.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.494-504
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• 2023

Sik-hae is a traditional and well-liked salt-fermented seafood with a low salt concentration in Korea. However, it is challenging to find data on market degradation. This study was conducted to investigate sensual characteristics, such as taste, odor and color, of 10 types of commercial Sik-haes [flounder (5 type), Alaska pollock (2 type), black edged sculpin, anchovy, and sandfish] as basic data for developing new products. The salinities of the commercial Sik-haes were significantly difference in the range of 3.0-6.7%. The pH and total acidity of 10 types of commercial Sik-haes were 4.45-5.24 and 0.84-1.46 g/100 g, respectively. The amino acid nitrogen and free amino acid contents, and total taste value were 72.0-333.0 mg/100 g, 425.6-1,726.4 mg/100 g and 17.0-115.9, respectively. According to the taste value, the major taste-related amino acids were aspartic acid and glutamic acid. Volatile basic nitrogen content and Hunter redness value of commercial Sik-haes were 24.5-80.9 mg/100 g and 10.9-28.5, respectively. However, food-grade additives, such as citric acid and monosodium, are occasionally used in commercial Sik-haes to achieve a lower pH or enhance flavor and aroma.

• Journal of Mushroom
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• v.22 no.2
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• pp.53-59
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• 2024

This study analyzed the effects of different nitrogen sources in substrate composition on the growth of Pleurotus ostreatus, as well as the subsequent changes in flavor and antioxidant activity. The T2, composed of poplar sawdust, beet pulp, cotton seed dregs, and cotton seed coat in a ratio of 40:20:20:20, exhibited the highest yield at 156.6 g. The total polyphenol content and ABTS and DPPH radical scavenging activities were 8.25 mg GAE/g, 70%, and 49%, respectively, showing higher radical scavenging activity compared to the Control and T1. Additionally, varying nitrogen content resulted in distinct aroma patterns and is presumed to influence taste profiles such as sourness, umami, and saltiness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.2
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• pp.259-266
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• 2011

This study was performed to develop an odor-reduced Korean traditional Cheonggukjang (fermented soybean paste) by adding Job's tears to Cheonggukjang made with soybean (control) only. The study included the determination of best addition percentage of Job's tears versus soybean, sensory evaluation, and aroma patterns and its components as well as proximate composition analyses of Cheonggukjang. Job's tears Cheonggukjang (CAJT) was prepared by inoculating Bacillus subtilis and fermented at $40^{\circ}C$ for 48 hours. Ratios of soybean : Job's tears for Job's tears Cheonggukjang were 1:1, 2:1, 3:1, and 4:1, respectively. In comparison of proximal composition, Job's tears Cheonggukjang was high in moisture and carbohydrates, but low in calorie, fat, protein, ash and amino nitrogen. The pH of CAJT was lower than those of control and conventional Cheonggukjang (CC) sold in the market, and the acidity was the lowest in CC. The color of Job's tears Cheonggukjang appeared the whiter and more yellowish, but less reddish in proportion to contents of Job's tears. The contents of viscous substances were higher in CAJT compared with those of control and CC. The contents of glutamic acid, the major components of viscous substances were lower in CAJT than in control and CC, and the contents of fructose higher in CAJT. The scores of sensory evaluation were the highest in Job's tears Cheonggukjang mixed with soybean : Job's tears=4:1. The aroma pattern of CC analyzed was conspicuously dissimilar to the control and CAJT and also discriminated by electronic nose examination. The pyrazines, volatile compounds peculiar to Cheonggukjang, were found to be lower in CAJT by SPME-GC/MS assay. Additionally, the acetic acid, butanoic acid, and naphthalene causing off-flavor were identified in CC, but not in Job's tears Cheonggukjang. The strength of odor through sensory evaluation was by far the lowest in CAJT among the groups. From the findings, it had shown that Job's tears Cheonggukjang would be produced successfully when the ratio of 4:1 (soybean : Job's tears) is employed. Also, it was proved that appropriate ratio of Job's tears addition makes Cheonggukjang odor-reduced and well accepted by people.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1239-1245
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• 2005

Hallabong peel oils grown in open field and green house were extracted by hand-pressing flavedo and collected on ice. Volatile flavor components of Hallabong peel oils were identified and compared by using gas chromatography and mass- spectrometry. Forty-four flavor components were identified in open field oil and 45 flavor components in green house oil. (E) -Limonene-1,2-epoxide and neral were identified only in Hallabong oil grown in open field, on the other hand, $\beta$-cubebene, $\beta$-elemene and decyl acetate were detected only in green house oil. Limonene was the most abundant component in both oils as more than 86$\%$ of peak weight, followed by sabinene (1.8$\~$ 3.6$\%$) and myrcene (2.4$\~ $2.6$\%$). The difference of the volatile profile between open field and green house oils were significantly characterized by identification and quantity of alcohol group. The total alcohols in open field and green house oils accounted for 1.8$\%$ and 0.8$\%$, respectively. Among alcohols, the level of linalool was relatively high in open field oil (1.2$\%$), however, it accounted for 0.5$\%$ in green house oil. Flavor properties of fresh Hallabong peel and flesh were also examined by sensory evaluation. Flavor properties of fresh Hallabong grown in open field were relatively stronger on both peel and flesh by sensory analysis. Sweetness was strong in Hallabong flesh from open field, and sourness in that from green house. The sensory evaluation of the preference in consideration of taste and aroma was significantly high in Hallabong grown in open field (p<0.01). From the present study, the stronger flayer properties and the preference of Hallabong from open field by sensory evaluation seem to be associated with the high level of linalool in its peel oil, and the composition of monoterpene hydrocarbons such as sabinene and (E) -$\beta$ -ocimene.