• Korean journal of food and cookery science
• /
• v.14 no.3
• /
• pp.250-254
• /
• 1998

A variation of free sugar and amino acid contents of pears during the ripening period was determined by HPLC and amino acid analyzer. The research results are as follws: Fructose, glucose and sucrose were present in the pears. The contents of fructose was the highest, followed by glucose and sucrose in order. The contents of total sugar in Shingo and Youngsan was similar, but the contents of frucose in Shingo was lower and the contents of sucrose was higher than that of Youngsan (p＜.001). During the ripening period, the contents of fructose and glucose gradually increased during the harvesting season and then somewhat decreased. The contents of sucrose increased continually, while the contents of total free sugar reached the maximum during the harvesting season, it was 10.41%, 10.29% in Shingo and Youngsan and then decreased gradually. The contents of total free amino acid in Shingo was higher than that of Youngsan. A variation ratio and the composition of amino acid in Shingo and Youngsan during the ripening period didn＇t make a significant difference. The major free amino acid of the pears was in the order of aspartic acid, serine, threonine, histidine, glutamic acid, valine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, methionine, isoleucine, leucine, histidine, and Iysine increased gradually. Glutamic acid, alanine, valine, arginine didn＇t show much change. The contents of total free amino acid increased during the ripening period.

• Food Science and Preservation
• /
• v.13 no.5
• /
• pp.581-588
• /
• 2006

Dynamic changes of free sugar and amino acid in the mixture of red bean paste sediment by corn syrup concentration and heating conditions were monitored. Glucose and fructose contents of red bean paste increased with an increasing blown color intensity. Amino acid content was affected by the heating temperature, increased with an increase in browning color intensify. Browning color intensity of each samples increased up to $95^{\circ}C$, but decreased above $95^{\circ}C$. This result was the same tend as changes of glucose and amino acid. The result of correlation coefficients among free sugar amino acid and browning color intensity show that increase in browning color intensity was not correlated directly with changes of free sugar and amino acid content. It seems that the contents of free sugar and amino acid resolved from saccharides and protein were much mote than contents nea for browning reaction.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.24 no.6
• /
• pp.911-916
• /
• 1995

Even though the saps have been consumed as beverage in Korea for a very long period of time, a little research has been conducted on the chemical composition. We determined mineral, free sugar, composition amino acids and nucleotides in the sap of Gorosoe(Acer mono Max.) and Sugar Maple(Pseudo-sieboldianum Kom.) collected from Sancheong, Kurye and Hamyang. The contents of solid, crude protein and ash were 1.1~3.3%, 0.03~0.12% and 0.02~0.05% in the sap of Gorosoe and Sugar Maple, respectively. The detectable nucleotides were CMP, UMP, IMP, GMP, AMP and hypoxanthine. Free sugar that we determined in the sap of Gorosoe and Sugar Maple were sucrose, fructose and glucose, but maltose was not detected. The chief component of saccharides in the sap was sugar and ranged from 7.1 to 36.6g/L. Especially, the sucrose contents in the sap of Gorosoe and Sugar Maple from Hamyang were higher 3.7 and 2.2 times than those from the other samples. The prominent minerals in the sap were calcium and potassium. The calcium concentration was ranged from 99.0~153.3mg/L in the sap of Gorosoe and was ranged from 21.2~32.4mg/L in that of sugar maple. The sap of Gorosoe and Sugar Maple were composed of 18 and 15 kinds of amino acid respectively, and the total contents of amino acid were in the range of 0.7~29.3mg%. The major amino acids in the sap of Gorosoe were taurine, serine, glutamic acid and aspartic acid in decreasing order. Taurine contents in the sap of Gorosoe and Sugar Maple was found to be the dominant amino acid.

• Food Science and Preservation
• /
• v.14 no.6
• /
• pp.624-632
• /
• 2007

Changes in proximate composition, amino acid, free sugar, reducing sugar and vitamin contents of Curcuma longa L. (autumn woolgeom in Korean) and Curcuma atomatica Salib (spring woolgeom) were investigated according to picking time. Moisture, crude ash, crude protein and crude lipid were increased and non nitrogen substances was decreased by extending the picking time. Contents and ratio of total amino acid to essential amino acids was increased by extending the picking time. Free amino acid was increased by extending the picking time. Ratio of essential amino acids to total amino acids was decreased. Fructose was gradually increased, and then glucose, sucrose and total free sugars were decreased by extending the picking time. Amino acid and sugar contents of Curcuma longa. L. were higher than those of Curcuma atomatica Salib. In contents of vitamin C and $B_1$, Curcuma longa L. was decreased and Curcuma atomatica Salib was increased by extending the picking time.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.5
• /
• pp.442-453
• /
• 2019

The purpose of this study was to compare differences in the main food components between Korean and imported quinoa from Peru, the U.S., and Thailand. Proximate composition of Korean quinoa showed highest crude protein and crude ash, while Korean quinoa had lowest moisture. Total amino acid content was higher in Korean quinoa than in imported quinoa. Fatty acid content was highest in quinoa cultivated in the U.S. and Wonju. Quinoa cultivated in Wonju was rich in palmitic acid, lignoceric acid, linoleic acid, eicosadienoic acid, erucic acid, and nervonic acid. Mineral content was higher in Korean quinoa than in imported quinoa. Quinoa cultivated in Wonju showed highest contents of P, Mg, Zn, while quinoa cultivated in Hongcheon showed the highest content of Na. Citric acid was found the major organic acid in quinoa. Citric acid content was highest in quinoa imported from the U.S. and lowest in quinoa cultivated in Hongcheon. Among free sugar, raffinose and glucose contents were highest in quinoa cultivated in Hongcheon, The results of this study show Korean quinoa has high contents of protein, amino acids, fatty acids, minerals and free sugar, offering essential amino acids in an excellent balance.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.2
• /
• pp.139-144
• /
• 1996

Effects of anaerobic, mechenical wounding and cold treatments on free amino acid and free sugar contents were examined in 7 day-old barley seedlings. In barley shoots under anaerobic condition, drastic changes in free amino acid content were observed. Alanine, ${\gamma}$-aminobutyric aicd(GABA) and glutamic acid contents changed most prominantly. Alanine and GABA contents increased rapidly with incubation time up to 10 hr. Glutamic acid content, however, decreased drastically during the first 5 hr of incubation, then increased thereafter. Barley shoots showed similar but smaller changes in amino aicd contents in response to mechanical wounding. GABA content increased in shoots and roots in response to the cold treatment. But increase in GABA content was greater in anaerobic than cold treatment. In anaerobically treated shoots, changes in free sugar content were less prominant than those in amino acid content. Sucrose content changed relatively larger than glucose and fructose contents in excised shoots.

• Journal of the Korean Society of Food Culture
• /
• v.12 no.2
• /
• pp.149-153
• /
• 1997

A variation of free sugar and free amino acid contents of apples during the ripening period was determined by HPLC and amino acid analyzer. The research results are as followes: Fructose, glucose and sucrose were present in the apples. The contents of fructose was the highest, followed by the order of sucrose and glucose. The contents of total sugar in Red fuji was relatively higher than that of Fuji. During the ripening period, the contents of fructose increased conspicuously for the harvesting season and then it decreased gradually. The contents of glucose increased gradually for the harvesting season and then it somewhat decreased. The contents of sucrose increased continually, while, the contents of total free sugar reached the maximum for the harvesting season and then it decreased gradually. A variation in the contents of free amino acid and composition during the ripening period didn't make a significant difference. The major free amino acid of the apples was in the order of aspartic acid, serine, threonine, glutamic acid, histidine, arginine, and alanine. During the ripening period, aspartic acid, threonin, serine, alanine, histidine, and arginine increased gradually. Especially, alanine, histidine, and arginine increased remarkably after the the harvesting season. Glutamic acid, valine, isoleucine, and leucine didn't show much change. The contents of total amino acid increased little by little as the apples ripened, dranstically increased during the harvesting season and slowly increased or slightly decreased after the harvesting seasom.

• Korean journal of food and cookery science
• /
• v.9 no.2
• /
• pp.82-87
• /
• 1993

This experiment was carried out to determine the total dietary fiber content and free sugar, fatty acid, amino acid compositions in bamboo shoot, lotus root and burdock. Bamboo shoot contained 3.05% of proteins, 0.48% of lipids, 2.45% of fibers, which were larger than those of other samples (lotus root and burdock). Burdock contained more sugars than the others as 18.64%. On a dry matter basis, total dietary fiber by Prosky AOAC method were 62.5% for bamboo shoot, 17.9% for lotus root and 41.9% for burdock. Therefore, the content of dietary fiber in bamboo shoot was the most abundant among them. Free sugar contents (glucose, fructose and sucrose) of the sample were analyzed by HPLC. Sucrose was the most abundant in both bamboo shoot and lotus root, and the content of fructose and sucrose in burdock were almost same. The major fatty acids in bamboo shoot, lotus root and burdock analyzed by GC were palmitic and linoleic acid. Also, linolenic acid were abundent only in bamboo shoot. The results of amino acid analysis showed that aspartic acid, glutamic acid and Iysine were the most abundent amino acids in the sample. Bamboo shoot contained large percentage of protein, the sweet-tasting amino acids and lipid than the other samples. Therefore bamboo shoot can be used as a flavor material because they contain plenty of the sweet-lasting amino acid and free sugar. Bamboo shoot and burdock can be used as potential source of dietary fiber because of the high content of dietary fiber in those samples.

• Journal of Ginseng Research
• /
• v.20 no.1
• /
• pp.36-41
• /
• 1996

Chemical components of Panax (P) species were compared. p. species used were Korean white ginseng, Korean, Chinese and Japanese red ginseng (P ginseng), American and Canadian ginseng (P. quinquefolium) , and sanchl ginseng (P. notoginseng). No significant difference in the proximate contents was observed among P. species. Ash, crude lipld and total sugar contents in root of P. notoginseng were found to be relatively lower than those of P. ginseng and P. quinquefolium, but the contents of crude protein and crude fiber were similar among those ginsengs. Mineral nutrient con tents showed a little difference among ginseng species. Total nitrogen contents were slightly higher in P. ginseng than P. quinquefolium and P. notoginseng and Fe and Cu were lower in Chinese and Japanese red ginsengs. Kinds and compositions of amino acids were similar but contents of amino acids were different among ginseng species. Total amino acid contents were 76.3∼83.9 mg/g in P. ginseng 53.8∼60.4 mg/g in p. quinquefolium and 54.9 mg/g in P notoginseng. Free sugar contents were lower in P. notoginseng than P. ginseng or P. quinquefolium. Sucrose accounted for 90∼92% of total free sugar contents with relatively high content in white ginsengs, while sucrose and maltose were 32-36% and 55∼60%, respectively, in red ginseng.

• Food Science and Preservation
• /
• v.6 no.1
• /
• pp.61-65
• /
• 1999

This study was carried out to investigate change in the components according to drying methods of jujube. Raw jujube was dried with five methods such as sun-drying, hot-air drying after pretreated with sunlight, blanching, microwave treatment, respectively. The contents of soluble sugar and protein in sun-dried jujube were higher than those of other drying methods. The free sugars of dried jujube were consisted of sucrose, glucose and fructose. And the contents of free sugar was not different by drying methods. The major organic acids of dried jujube were oxalic acid, citric acid and malic acid. The contents of glutamic acid, glycine and alanine were higher than those of other amino acids, and the content of each amino acid was not different by drying methods.