• Korean journal of food and cookery science
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• v.26 no.5
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• pp.655-664
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• 2010

This work aimed to investigate the physiochemical properties of commercial sugars (white sugar, dark brown sugar, organic sugar, and muscovado) and sugar beet. Percentages of crude protein, crude fat and crude fiber in sugar beet were 4.06, 6.36 and 0.02%, respectively, and the degrees of sugar of white sugar and sugar beet were $93^{\circ}$ Brix and $78^{\circ}$ Brix, respectively. L(lightness) value scores of white sugar were higher while the turbidity of sugar beet was higher. White sugar, dark brown sugar, and organic sugar were composed of only sucrose, whereas muscovad and sugar beet were composed of fructose, glucose, and sucrose. The highest organic acid content was observed in sugar beet. The contents of amino acids in sugar beet were in the following order: proline ($161.23\;{\mu}g$/100 g) > aspartic acid ($161.23\;{\mu}g$/100 g) > leucine ($36.93\;{\mu}g$/100 g) > alanine ($17.40\;{\mu}g$/100 g). There were 16 free amino acids in sugar beet. The highest mineral contest was observed in sugar beet in the order of K > Ca > Na > Mg. This result indicates that sugar beet can be prepared by considering the characteristics of natural sugar materials.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.101-108
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• 2016

We investigated changes in the physiochemical quality of sailfin sandfish sauces fermented with two kojis during long-term storage at room temperature. Four fish sauces, including a control, were prepared by salt-fermentation with soybean koji (S-koji) or rice koji (R-koji) after autolysis. During storage, for 12 months, the color and levels of amino acids, total volatile base nitrogen (T-VBN) and organic acids but not moisture, salt or total nitrogen levels or pH differed markedly according to fish sauce type. The total nitrogen level was highest in S-koji, but there was no difference in the rate of increase in amino acid levels among the four fish sauces during storage. The T-VBN, of autolysis and S-koji were significantly higher than those of the control and R-koji during the entire storage period (P<0.05). The initial organic acid level did not differ among the four fish sauces, whereas it was notably higher in R-koji than in the other sauces at the end of storage. Hunter L, a and b values decreased in all fish sauces with increasing storage time. In conclusion, soybean koji may enhance the levels of nitrogen compounds as well as T-VBN in fish sauce, while rice koji reduced the formation of excess T-VBN and increased organic acid levels during storage at room temperature.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.332-340
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• 2009

This study was conducted to analyze and determine formation potentials for chlorination disinfection by-products (DBPs) from twenty amino acid compounds with or without $Br^-$. Two of twenty amino acid compound were tryptophan and tyrosine that were relatively shown high for formation of trihalomethanes (THMs)/dissolved organic carbon (DOC) whether or not $Br^-$ presented. Other 18 compounds were shown low for formation of THMs/DOC whether or not $Br^-$ presented. Five amino acid compounds that were tryptophan, tyrosine, asparagine, aspartic acid and histidine were shown high for formation of haloacetic acids (HAAs)/DOC whether or not $Br^-$ presented. Although formation of dichloroacetic acid (DCAA) was dominated in asparagine, aspartic acid and histidine, trichloroacetic acid (TCAA) was dominated in tryptophan and tryptophan. The formation of haloacetnitriles (HANs)/DOC whether or not $Br^-$ presented was high in Aspartic acid, histidine, asparagine, tyrosine and tryptophan. Specially, aspartic acid was detected 660.2 ${\mu}$g/mg (HAN/DOC). Although the formation of chloralhydrate (CH)/DOC was shown high in asparagine, aspartic acid, histidine, methionine, tryptophan and tyrosine, the formation of Chloropicrin (CP)/DOC was low (1 ${\mu}$g/mg) in twenty amino acid compounds. The formations of THM, HAA and HAN were also investigated in functional groups of amino acids. The highest formation of THM was shown in amino acids compounds (tryptophan and tyrosine) with an aromatic functional group. Highest, second-highest, third-highest and fourth-highest functional groups for formation of HAA were aromatic, neutral, acidic and basic respectively. In order of increasing functional groups for formation of HAN were acidic, basic, neutral and aromatic.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.11-14
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• 1999

This experiment was conducted to estimate seasonal changes in the properties and chemical components of xylem sap from 'Hayward' (Actinidia chinensis Planch) and wild kiwifruit species (Actinidia aguta Sieb. et Zucc. Planch) in 1996 and 1997. Amount of bleeding sap from kiwifruit vines considerably decreased with collection time in both species. There was no difference in water content, soluble solid content, viscosity, and pH of the sap between 'Hayward' and wild species, while turbidity and organic acid contents were much higher in 'Hayward'. Fructose content was highest among free sugars, followed by glucose, sucrose, galactose and manitol in 'Hayward', but only low concentration of fructose and glucose was detected in wild species. The major inorganic components in the sap were calcium, potassium, and magnesium, and calcium was dominant among them. The saps of 'Hayward' and wild species were composed of 17 kinds of amino acids respectively, and major amino acids were glutamic acid, lysine, and isoleucine. Glutamic acid content was highest in both species and except histidine, contents of methionine and tyrosine were much higher in 'Hayward' than wild species. Concentrations of inorganic elements and amino acids were slightly increased with delaying collection time, but sugar contents decreased.

• Korean Journal of Organic Agriculture
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• v.11 no.2
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• pp.91-101
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• 2003

This study was tried to examine the efficacy of apples that had grown with agro-chemical alternatives in an apple orchard. The chlorophyll content of apple leaves was a little higher in the plot of Charcoal powder, Chitosan, and Peat moss treatment among the other agro-chemical alternatives. On the contrary, the sugar content of apple fruits was higher in the plot of Amino acids, and Green ion calcium treatment, but there was quite a difference among them. Vitamin C content of apple fruits was high at the cell division period. It became lower at the hypertrophic period and then got higher again at the harvest. Vitamin C content was the highest in the chemical fertilizer plot as well. In an apple orchard where agro-chemical alternatives were used only, the commercial grade of ripened apples had declined by 25％, compared to those in customary cultivation. The commercial grade of ripened apples with agricultural chemicals using fertilizers and pesticides was over 90％ with over 250g of its weight in the plot of Charcoal powder, Amino acids, and Vitamin C treatment. Therefore. we guessed the environment-friendly method of cultivation in an apple orchard shall be established by reducing the usage of agricultural chemicals gradually and increasing the agro-chemical alternatives at the same time.

• Food Science and Preservation
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• v.7 no.3
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• pp.278-284
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• 2000

The chemical components in freeze dried Korean Gastrodia elata blume powder were analyzed. The proximate composition was composed of moisture(2.12%), crude protein (4.41%), crude fat(1.20%), crude ash(2.25%), crude fiber(4.60%) and N-free extract(85.15%). Free sugar was composed of glucose(1,314mg%), sucrose(1,081mg%) and fructose(869mg%). Total organic acid content was 2,095mg% and composed of succinic acid(1,238mg%), citric acid, malic acid, oxalic acid and fumaric acid in the order. Among the 11 fatty acids detected, linoleic acid was the most predominant one and unsaturated fatty acid was 80.55 area percent. 18 and 39 amino acids were detected from total and free amino acid, respectively. Arginine, asparagine, proline and sarcosine were the major components of free amino acid. The content of crude saponin and total phenol were 3,768mg% and 821mg%, respectively. Ascorbic acid(6.4mg%), vitamin B1(1.2mg%), vitamin B2(1.7mg%) and niacinamide(0.2m%) were detected as soluble vitamins of the powder. The content of vitamin A and vitamin E was 1.22mg% and 0.32%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1799-1805
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• 2015

Rice vinegar (RV) is primarily made from fermented rice or rice wine in Korea, China, and Japan. Ten commercially available naturally-fermented rice vinegars produced in Korea (KRV1~4), China (CRV1~2), and Japan (JRV1~4) were comparatively investigated for their physicochemical properties and antioxidant activities. KRV showed a significantly higher total acidity range (5.07~6.27) than both CRV (4.67~4.84) and JRV (4.64~4.84). These acidity ranges corresponded with respective standards of each country: Korea (Food Code), China (GB), and Japan (JAS). Six different organic acids were detected in RVs; acetic acid and succinic acid were the most prominent. Thirty different amino acids were detected in RVs, and main identified amino acids were alanine (KRV), phenylalanine and aspartic acid (CRV), and leucine and alanine (JRV). ${\gamma}-Aminobutyric$ acid was detected at high concentration in KRV1. KRV1 showed maximum total phenolic content, and DPPH and ABTS radical scavenging activities of samples were also determined with significantly increasing tendency. KRV1 (produced from brown rice with aging period of >1 year) exhibited the highest free amino acid content and antioxidant activity as compared to CRV and JRV.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.119-124
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• 2006

Natural organic matter (NOM) should be carefully considered in terms of its constituent and effect because NOM is complex substances that occur in spatially and seasonally varying concentrations in natural water. This review presents characteristics of natural organic matter present in water. These compounds mainly include humic substances, carbohydrates, proteins (amino acids), hexosamines, fats, oils, greases, and trace organic compounds (endocrine disrupting chemicals and pharmaceuticals and personal care products).

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.436-444
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• 1991

To increase both the production of mushrooms and the usages of the residues (used media) for roughage, the pinchips(PC) and sawdusts(SD) of three Korean oak species were tested as cultivating media for Lentinus edodes with varing the composition of the media. The results are as follows. 1. Organic acids(tannic acid and citric acid), which were added in the PC medium to enrich the quality of mushrooms, did not increase the growths of the mycelia and the quality. 2. The mushrooms were able to be harvested from six months after beginning the cultivation. No significant differences were found among the qualities of the mushrooms produced by various treatments. 3. The contents of crude proteins(1.82-4.55%) in the used media were higher than those in woods (c.a. 0.7%), and the total digestible nutrients (44.0-46.0%) in the used medium were not much different from those in rice straws (c.a.48.0%). 4. The contents of some essential amino acids (methionine in the used medium of the tannic acid added PC or S.D. and isoleucine, phenylalanine and lysine in the used medium of the untreated PC or SD) were higher than those in the control (raw media). The contents of a few other essential amino acids (threonine, valine and arginine) were lower in the used media. Most nonessential amino acids in the used media, particularly in the used bed-log, appeared to decrease than those in the control.

• 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.