• Food Science of Animal Resources
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• v.21 no.1
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• pp.80-88
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• 2001

This study was carried out to evaluate the different physicochemical properties of various lipid sources in beef patties during storage for 6 months. Four groups of samples were made of beef meat patties with 22% of tallow, lard, chicken fat and 20% of palm oil. On the analysis result of physicochemical compositions, the patty has its own fatty acids composition and characteristic different from other lipids. Patty with chicken fat has the highest percentage of unsaturated fatty acid composition of 61.0% compared to the other groups of patties. Beef patty with chicken fat has 18.8% of poly unsaturated fatty acid(USFA) and beef patty with beef lipid has 1.5% of poly USFA which is the least percentage among the others. SFA/USFA ratio of beef patty with chicken lipid was 0.5 which was the least value. The composition of PUFA in beef patty with lard increased to 10.0% from 1.9% over initial value after storage for 6 months. On the contrary, the composition of PUFA in beef patty with chicken fat decreased to 9.2% from 18.8% over initial value after 6 months. Volatile free fatty acids of beef patties were evaluated with four kinds of lipid sources. Formic acid was the most as of 59$\mu\textrm{g}$/g in beef patty with tallow, acetic acid was 15$\mu\textrm{g}$/g, and heptanoic acid was 10$\mu\textrm{g}$/g at starting time of storage. However, propionic acid, butyric acid, valeric acid and caproic acid were not detected. After 6 months, formic acid decreased from 59$\mu\textrm{g}$/g to 7$\mu\textrm{g}$/g in the patty with tallow, from 12$\mu\textrm{g}$/g to non-detect level in the patty with palm oil, but two the others patties slightly increased. Volatile compounds in meat patties were reported nearly 1000 kinds of chemical compounds. Beef patty with tallow has aldehydes 5.3, alcohol 1.3, hydrocarbon 0.8, ketones 0.2, ester 0.1, furans 0.1, acid 0.04, sulfur 0.03 in peak area at starting and increased to aldehydes 8.5, alcohol 2.1, ketones 0.5, ester 1.0, furans 1.5 in peak area during the storage. But only furans was not detected after 6 months of storage. From starting to 6 months, aldehydes increased 2∼10 times, alcohol increased 2∼3 times, acids 4∼50 times and ester 9∼20 times in beef patties with pork lipid, chicken lipid and palm oil. Some volatile compounds such as alcohol, aldehydes and acids in all kinds of patties significantly increased after 6 months of storage. These increases cause oxidative rancidity taste in meat patties. These results showed that selt-life of meat patties with 4 different lipids were not over 6 months even though they were stored at -20$^{circ}C$. Therefore, they should be classified as off-grade because of oxidative rancidity. Although beef patties with tallow are currently common type, the possibility for new type of hamburg patty can be developed by applying different lipids. Finally, we found out new type of beef patty added with lard, which has the best taste and quality compared to the other common types.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.107-112
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• 2001

The various components of sigumjang were analyzed according to fermentation time. Aerobic bacteria were increased with fermentation time. Yeasts and molds were increased until 3 days after fermentation and then not changed. Six free sugars, 3 volatile organic acids and 6 non-volatile organic acids were detected. The content of free amino acids was $1,407.9{\sim}3,053.9\;mg%$. Glutamic acid was most abundant component among the amino acids, followed by phenylalanine, arginine and valine. The ratio of essential amino acid was $34.4{\sim}37.0\;mg%$. The content of mineral was $12,966.7{\sim}13,864.5\;mg%$. Potassium was the most abundant in quantity among the minerals in sigumjang except sodium which was added artificially. The principal fatty acids were linoleic acid, palmitic acid and oleic acid. The ratio of unsaturated fatty acids was $76.3{\pm}1.1%$. As a result of sensory evaluation, the highest score was obtained 3 to 5 days after fermentation.

• Animal Bioscience
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• v.36 no.6
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• pp.962-972
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• 2023

Objective: This study determined the effects of dietary treatments and castration on meat quality, fatty acids (FAs) profiles, and volatile compounds in Korean native black goats (KNBG, Capra hircus coreanae), including the relationship between the population of rumen microbiomes and meat FA profiles. Methods: Twenty-four KNBG (48.6±1.4 kg) were randomly allocated to one of four treatments arranged into a 2×2 factorial structure. The factors were dietary forage to concentrate ratio (high forage [HF, 80:20] and low forage [LF, 20:80]), and a castration treatment (castration [CA] vs non-castration [NCA]). Results: Among meat quality traits, the CA group exhibited a higher percentage of crude fat and water holding capacity (p<0.05). The profiles of the saturated fatty acid (SFA) in meat sample derived from CA KNBG showed a significantly lower percentage compared to NCA individuals, due to the lower proportion of C14:0 and C18:0. Feeding a high-forage diet to KNBG increased the formation of C18:1n7, C18:3n3, C20:1n9, C22:4n6 in meat, and polyunsaturated fatty acid (PUFA) profiles (p<0.05). Consequently, the n6:n3 ratio declined (p<0.05). There was an interaction between dietary treatment and castration for formation of C20:5n3 (p<0.05), while C18:1n9, C22:6n3, monounsaturated fatty acid (MUFA) and the MUFA:SFA ratio were influenced by both diet and castration (p<0.05). Nine volatile compounds were identified and were strongly influenced by both dietary treatments, castration (p<0.05), and their interaction. In addition, principal component analysis (PCA) revealed distinctly different odor patterns in the NCA goats fed LF diets. Spearman correlation analysis showed a high correlation between rumen bacteria and meat PUFAs. Conclusion: These results suggest the essential effects of the rumen microbial population for the synthesis of meat FAs and volatile compounds in KNBG meat, where dietary intake and castration also contribute substantially.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.427-431
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• 2002

Alkali treatment following acidic hydrolysis (ATAH) is a commonly used practice for reducing the levels of monochloropropanediol in commercial Korean soy sauce. This study investigated the chemical compounds produced in commercial Korean soy sauce made by ATAB. The levels of amino-N, total acidity, pH, salinity and Brix of the soy sauce were 6.66%, 2.52%, 19.81%, 4.57 and 35.01, respectively. The major fatty acids were C18:2n-6, C16:0, Cl8:ln-9 and C18:3n-6. The concentration of polyunsaturated fatty acids were especially high, with of C18:2n-6 (49.8%) being the highest followed by C18:3n-6 (3.8%) and C18:3n-3 (2.4%) in that order. Among the non-volatile organic acids, the concentration of levulinic acid (1,206.28 mg/100 g) was the highest, while the taste value of citric acid was the highest. Among the ATP related compounds, IMP concentration (31.19 mg/100 g) was highest followed by AMP, hypoxanthine and GMP in that order. The concentrations of free and total amino acids in soy sauce were 6,136.94 mg/100 g and 8,702.76 mg/100 g, respectively. On the other hand, the taste value of glutamic acid, a major amino acid flavor determinant in soy sauce, was highest of all the amino acids, which is desirable since most free amino acids such as methionine, histidine and phenylalanine have a bitter taste that detracts from the flavor of soy sauce.

• Applied Biological Chemistry
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• v.9
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• pp.9-27
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• 1968

Studies were carried out in order to elucidate chemical components and microflora in three types of soy-sauce, 12-year aged soy-sauce prepared by improved method. 7-year aged and 20-year aged soy-sauce prepared by ordinary method. They results are summarized as follows: 1. The followings are found to be the important factors affecting the quality of soy sauce. a. Organic acids, reducing sugars and free amino acids were increased in the course of storage. b. In the aged soy-sauces under study non-volatile organic acid increased while volatile organic acid decreased and the total acidity was dependent only upon tie latter. c. It was found that suit concentration decreased during the storage. 2. The results of investigation of microflora in the stored soy-sauce are shown as follows. Soy-sauce Improved Ordinary Microbe 12-Y. 20-Y. 7-Y. Aerobic bacteria colony/1ml. 6 123 2 Halophilic lactic acid bacteria colony/1ml. 4 6 10 Osmophilic yeast colony/1ml. $828{\times}10^4$ 248 - b. In the stored soy-sauces, aerobic bacteria are incapable of growing due to drop in pH value and the influence of salt concentration. c. Halophilic lactic acid bacteria are incapable of growing due to drop in pH value, even the salt concentrations decreased during the storage. d. Osmophilic yeast are still growing in low pH value and in the decreasing salt concentration during the strage. 3. The results of amino acid analysis by paper partition chromatographic and calorimetric methods are shown as follows. a. Fourteen kinds of amino acid and thirteen amino acids were detected in the soy-sauce of 12-year aged improved soy-sauce and 7-year aged and 20-year aged ordinary one, respectively. b. The contents of aspartic acid, glutamic acid, serine, valine, leucine, lysine, histidine and methionine increased in the 20-year aged ordinary soy-sauce compared to the 7-year aged one. On the other hand those of alanine, tyrosine, phenylalanine and cystine decreased. 4. The results of sugar analysis by paper chromatography are as follows. a. In the 12-year aged improved soy-sauce, galactose, glucose, arabinose, xylose, rhamnose, maltose and an unknown were detected, and their amounts were in the above order except maltose and an unknown. b. Both in the 7 and 12-year aged ordinary soy-sauces, galactose, arabinose, xylose, glucose and rhamnose were detected and the amounts of the sugars were in the above order. c. In the non-aged ordinary soy-sauce, glucose was not detected but detected from 7-year and 20-year aged ordinary soy-sauce. 5. The results of organic acid analysis by paper chromatography were as follows. a. As volatile acids, acetic, propionic and butyric acids were detected in the 7-year aged ordinary soy-sauce. On the other hand in both the 20-year aged ordinary soy-sauce and the 12-year aged improved ones, only acetic acid was abundant while propionic and butyric acids were round in trace. It was found that propionic and butyric acids, as the unpleasant flavor components, decreased during the storage. b. In the ordinary soy-sauce, citric acid were produced during the storage and lack, malic and tartaric acids increased in the course of aging while succinic, glycolic, fumaric and malonic acids were shown to decrease. Glutaric and oxalic acids disappeared. Citric acid was produced also in the improved soy-sauce, but lactic, tartaric, succinic, malic, and glycolic acids decreased, while both malonic and glutaric acids disappeared. From the above results the citric acid production was considered to be a favorable factor for the taste. c. In the aged soy-sauces, pyruvic, α-ketoglutaric and probably acetoacetic and oxaloacetic acids (both in trace) were present and their amounts were in the above order. All of the α-keto acid abruptly decreased during the storage.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.702-709
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• 2014

Normal alcoholic fermentation took place at $20-25^{\circ}C$ in yakju (traditional Korean rice wine) prepared without the addition of protease (non-addition group). The total concentration of organic acids increased by 1.0-2.7 fold in the non-addition group. While the concentration of lactic acid and acetic acid increased, the pyroglutamic acid concentration decreased by 51.1 fold. Consequently, the total acidity and volatile acid concentration increased, and the overall pH decreased. Compared to the addition group, the non-addition group showed a 3.0-5.2 fold increase in the amount of amino acids; however, the total estimated concentrations of free-form amino acids were 5.2-11.9 times lower than those in the latter group. The major amino acids found in the non-addition group were alanine, arginine, leucine, and phenylalanine. The yakju preparation from the non-addition group showed a 1.2-3.0 fold decrease in the final color intensity as compared to that from the addition group.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.36-43
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• 2012

Objective of this study was to investigate the effects of pre-treatment of rice straw by sizes(3cm, milled), temperatures($35^{\circ}C\;and\;55^{\circ}C$), with/without NaOH treatment, and RPM on the characteristics of volatile fatty acids production. The concentration of total volatile fatty acids (TVFAs) was increased with the hydrolyzed time. Concentration of VFAs in milled rice straw was higher than that in 3 cm cut. With the alkali treatment, the concentration of TVFAs were sharply increased, which showed 3 times higher than non-treatment. Concentration of VFAs was high at 150 rpm at $35^{\circ}C$, and at 80rpm and 200 rpm at $55^{\circ}C$. Among them acetic acid was dominant, which showed the similar increase with TVFAs. It was also observed that in the case of fibrous material, the contents of cellulose and hemi-cellulose were reduced a little, but no change in lignin.

• Food Science of Animal Resources
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• v.44 no.3
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• pp.662-683
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• 2024

Thai-Native×Anglo-Nubian goat meat cooked by grilling (GR), sous vide (SV), and microwave (MW), was compared to fresh meat (Raw) in terms of flavor development. Non-volatile [i.e., free amino acids, nucleotide-related compounds, taste active values (TAVs) and umami equivalency, sugars, lipid oxidation, Maillard reaction products] and volatile compounds, were investigated. Notably, inosine monophosphate and Glu/Gln were the major compounds contributing to umami taste, as indicated by the highest TAVs in all samples. Raw had higher TAVs than cooked ones, indicating that heat-cooking removes these desirable flavor and taste compounds. This could be proportionally associated with the increase in aldehyde, ketone, and nitrogen-containing volatiles in all cooked samples. GR showed the highest thiobarbituric acid reactive substances (1.46 mg malonaldehyde/kg sample) and browning intensity (0.73), indicating the greatest lipid oxidation and Maillard reaction due to the higher temperature among all cooked samples (p<0.05). In contrast, SV and Raw exhibited similar profiles, indicating that low cooking temperatures preserved natural goat meat flavor, particularly the goaty odor. The principal component analysis biplot linked volatiles and non-volatiles dominant for each cooked sample to their unique flavor and taste. Therefore, these findings shed light on cooking method selection based on desirable flavor and preferences.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.68-75
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• 2000

Optimum processing conditions for vinegar fermentation using fig, pear and persimmon were determined. Alcohol contents in the fermentatio broth of crushed fruits of fig, pear and persimmon were 7.5%, 5.1% and 6.8%, respectively. Alcohol contents increased up to 14.3~15.1% by adding 24% of sugar to the fruit juices. The total acidity of 7.04%, 3.30% and 3.66% were obtained for fig, pear and persimmon, respectively, through acetic acid fermentation of fruit juices containing 8% ethanol. Acetic acid yield increased by shaking during fermentation for pear and persimmon broth. Acetic acid yield increased 1.80~1.92 times by adding 0.5% of yeast extract to the fermentation broth of pear and persimmon. After fermentation, each fruit vinegar was clarified up to 93.1~97.4 of light transmittance by using 0.6% of kaki shibu for 4 days at 1$0^{\circ}C$. After aging for 60 days at 1$0^{\circ}C$, the acidity of fruit vinegar decreased slightly. Tannin content of persimmon vineger was remarkably higher than the other, while light absorbance of pear vinegar was higher than the other vinegars. Acetic acid was identified as the main volatile organic acid in the fruit vinegars, while propionic, isobutyric and isovaleric acids were identified as the minors. The content of non-volatile organic acids in the pear vinegar was higher than that in the persimmon vinegar. Sensory evaluation results indicate that the fig vinegar was preferred to the pear vinegar in the aspects of color, flavor and overall acceptability, but the fig vinegar had a strong background taste. Sensory scores of the persimmon vinegar increased significantly by pasteurization, but those of the fig and pear vinegars did not by pasteurization.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.454-464
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• 1986

To find main factors to affect tobacco culture and quality, NC 2326 (Nicotiana tabacum L.) was cultivated in Korea and in the United States under different plant density, fertilization, mulching and curing. Among the chemical characteristics of the both experimental soils, the organic matters were similar concentration in both locations but effective phosphorous contents were higher in Oxford in the United States. Plant height, length and width of the largest leaf, leaf thickness, and midrib ratios were larger in Oxford than in Suwon in Korea. Also they were larger in non mulching system than in mulching system. But the total numbers of the leaves were decreased in non mulching system. The content of nicotine was higher in the plant grown in Suwon than in Oxford. The concentrations of nicotine and sugar tend to increase in mulching system comparing of non mulching system. During the growing, the concentration of non-volatile organic acids was higher in Suwon, while it was lower in cured leaf produced in Suwon. Also the contents of total fatty acids were lower in the harvested leaf grown in Suwon, but not in cured tobacco. Forty three compounds identified among the volatile oils from these experimental samples were quantified. The concentrations of the major components related to the tobacco flavour such as damascone, damascenone, solanone, nor-solanadione, and megastigmatrienones were higher in the cured tobacco produced in Oxford rather than in Suwon.