• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.249-254
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• 1997

Stevioside was transglucosylated to improve its sweetness. Eighteen conditions were tested using the tables of orthogonal arrays of $L_{18}\;(2^{1}{\times}3^{7})$. Statistical analysis showed that the transglucosylation rate was significantly affected by temperature, the ratio of co-substrate (maltodextrin) to stevioside, pH, DE of maltodextrin and concentration of stevioside, in their order. Optimum conditions selected for temperature, ratio of co-substrate to stevioside, pH and DE of maltodextrin were $80^{\circ}C$, 1.0, 6.0 and 15, respectively. Glycosyl-stevioside with 68% yield of transglucosylation was produced at the optimum condition and found to have better quality in sweetness than stevioside and rebaudioside A.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.69-89
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• 1981

Stevia (Stevia rebaudiana Bertoni) is a perennial herb widely distributed in the mountainous area of Paraguay. It belongs to the family Compositae and contains 6 to 12 percent stevioside in the leaves. Stevioside is a glucoside having similar sweetening character to surgar and the degree of sweetness is approximately 300 times of sugar. Since Korea does not produce any sugar crops, and the synthetic sweetenings are potentially hazardous for health, it is rather urgent to develop an economical new sweetener. Consequently, the current experiments are conducted to establish cultural practices of stevia, a new sweetening herbs, introduced into Korea in 1973 and the results are summarized as followings: 1. Days from transplanting of cuttings to the flower bud formation of 6 stevia lines were similar among daylengths of 8, 10 and 12 hours, but it was much greater at daylengths of 14 or 24 hour and varietal differences were noticable. All lines were photosensitive, but a line, 77013, was the most sensitive and 77067 and Suweon 2 were less sensitive to daylength. 2. Critical daylength of all lines seemed to be approximately 12 hours. Growth of plants was severely retarded at daylengths less than 12 hours. 3. Cutting were responded to short daylength before rooting. Number of days from transplanting to flower bud formation of 40-day old cuttings in the nursery bed was 20 days and it was delayed as duration of nursery were shorter. 4. Number of days from emergence to flower bud formation was shortest at short day treatment from 20 days after emergence. It was became longer as initiation of short day treatment was earlier or later than 20 days. 5. Plant height, number of branches, and top dry weight of stevia were reduced as cutting date was delayed from March 20 to May 20. The highest yield of dry leaf was obtained at nursery duration of 40-50 days in march 20 cutting, 30-40 days in April 20 cutting, and 30 days in May 20 cutting. 6. An asymptotic relationship was observed between plant population and leaf dry weight. Yield of dry leaf increased rapidly as plant population increased from 5,000 to 10,000 plants/10a with a reduced increasing rate from 10,000 to 20,000 plants/l0a, and levelled off at the plant population higher than 20,000 plants/l0a. 7. Stevia was adaptable in Suweon, Chengju, Mokpo and Jeju and drought was one of the main factors reducing yield of dry leaf. Yield of dry leaf was reduced significantly (approximately 30%) at June 20 transplanting compared to optimum transplanting. 8. Yield of dry leaf was higher in a vinyl house compared to unprotected control at long daylength or natural daylength except at short day treatment at March 20. Higher temperature ill a vinyl house does not have benefital effects at April 20 transplanting. 9. The highest content of stevioside was noted at the upper leaves of the plant but the lowest was measured at the plant parts of 20cm above ground. Leaf dry weight and stevioside yield was mainly contributed by the plant parts of 60 to 120cm above ground but the varietal differences were also significant. 10. Delayed harvest by the time of flower bud formation increased leaf dry weight remarkably. However, there were insignificant changes of yield as harvests were made at any time after flower bud formation. Content of stevioside was highest at the time of flower bud formation and earlier or later harvest than this time was low in its content. The optimum harvesting time determined by leaf dry weight and stevioside content was the periods from flower bud formation to right before flowering that would be the period from September 10 to September 15 in Suweon area. 11. Stevioside and rebaudioside content in the leaves of Stevia varieties were ranged from 5.4% to 14.3% and 1.5% to 8.3% respectively. However, no definit relationships between stevioside and rebaudioside were observed in these particular experiments.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.52-56
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• 1991

The browning reaction of sugar derivatives, fructo-oligosaccharide, high maltose syrup(HMS), sorbitol and maltitol, and their effect on the appearance of jam and candy were investigated. The spectrophotometrie scanning of the absorbance between 230 nm and 700 nm could demonstrate the heat induced browning of the sugar derivatives. Fructo-oligosaccharide and HMS showed sharp increase in absorbance at 270-330 nm range by heating at $100{\sim}120^{\circ}C$ for 1 hr but sorbitol and maltitol did not show the increase in absorbance. When the pH was lowered red from neutral to 2.0, the absorbance of HMS and sucrose increased sharply, showing that these substances are relatively unstable in acidic heating compared to fructo-oligosaccharide. The addition of glycine enhanced the browing reaction of fructo-oligosaccharide and HMS, whereas little change was observed with sucrose, sorbitol and maltitol. These browning characterisitcs of sugar derivatives were reflected to the color development of apple jam and candy where they were used. Both fructo-oligosaccharide and HMS increased the yellowness of these products, while sugar alcohols reduced the yellowness compared to sugar.

• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.277-283
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• 2017

To produce sweet liquor without artificial sweeteners, 8 traditional rice pre-treatment methods (juk, beombeok, seolgitteok, gumeongtteok, mulsongpyeon, injeolmi, gaetteok, and godubap) were analyzed in this study. The formation of sugars with the help of ${\alpha}$-amylase, ${\beta}$-amylase, and glucoamylase using nuruk as a substrate has been previously confirmed. During the early stages of the pre-treatment processes, the amount of maltose produced (in descending order of its concentration) by ${\alpha}$-amylase was observed to be as follows: gaetteok > seolgitteok > beombeok > mulsongpyeon > juk > injeolmi > gumeongtteok > godubap. However, changes in maltose concentrations with respect to the pre-treatment processes after 48 hours were observed to be as follows: injeolmi > beombeok = godubap > gumeongtteok > gaetteok = mulsongpyeon > seolgitteok > juk. Maltose produced using either ${\alpha}$-amylase or ${\beta}$-amylase showed similar results. Glucoamylase produced 10 mg/ml of glucose during the godubap process, which was the highest amount of glucose among all the methods. Moreover, when ${\alpha}$-amylase, ${\beta}$-amylase, and glucoamylase were used concurrently, glucoamylase increased glucose production in the later stages. Therefore, the possibility of producing sweet liquor without employing artificial sweeteners was confirmed, even if the amount of sugar in the liquor varied with the pre-treatment process.

• KSBB Journal
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• v.5 no.2
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• pp.125-131
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• 1990

Microbial production of L-phenylalanine using Corynebacterium glutamicum ATCC 21674, a tyrosine auxotroph resistant to aromatic amino acid analogues, has been studied and kinetic analysis was performed. Even though the strain was reported as a tyrosine auxotroph, it produced tyrosine and was able to grow on the minimal medium where no tyrosine was present. The average specific growth rate at the exponential growth phase was 0.087 hr-1. There was a dissociation of growth from the formation of the product. Linear correlation between biomass production and total CO2 production was obtained. The relationship between CO2 evolution rate and sugar consumption rate was also found to be linear.

• YAKHAK HOEJI
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• v.43 no.5
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• pp.614-622
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• 1999

The standard operation procedure of mouse lymphoma L5178Y $tk^{+/-}-3.7.2C$ gene mutation assay (MOLY) has been regarded as a sensitive in vitro mammalian cell gene mutation assay that is capable of detecting clastogens as well as mutagens. Using MOLY, one of natural sweetner, stevioside (5mg/ml) and its aglycon, steviol ($340{\;}\mu\textrm{g}/ml$) were evaluated the mutagenicity. Stevioside and steviol did not induce mutagenicity in MOLY. On the other hand, stevioside (250mg/kg, B.W.) and steviol (200mg/kg, B.W.) were also evaluated their ability to induce micronuclei in regenerating hepatocytes and bone marrow cells of ddY mice. From these results, stevioside and steviol did not induce any mutagenic effect both MOLY and in vivo micronucleus test.

• Food Science and Industry
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• v.49 no.3
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• pp.17-28
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• 2016

The concerns over obesity and obesity-related health problems are increasing as many consumers relate these health problems with sugar. The demand for sugar reduction is also rising and regulatory movement by governments including Korea is driven to reflect such demand. For the past decades, there have been diverse development and marketing of various sweeteners to substitute sucrose and high fructose corn syrup. Low caloric alternative sweeteners can be divided into high intensity sweeteners that have greater sweetness potency compared to sucrose, and low intensity sweeteners such as polyols, oligosaccharides and rare sugars that have less sweetness potency. This paper discusses representative low caloric alternative sweeteners, their market and trend.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.380-387
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• 2002

To investigate the effects of xylooligosaccharides on the in vitro growth of intestinal bacteria, various species were cultivated individually on the m-PYF medium containing a carbon source (0.5% w/v) such as xylooligosaccharides, isomaltooligosaccharides, fructooligosaccharides and sucrose, respectively. The health-promoting microorganisms such as Bifidobacterium bifidum, Bifidobacterium infantis, Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus grew more effectively by xylooligosaccharides than by other carbon source, though xylooligosaccharides inhibited the growth of Clostridium perfringens, Bacteroides fragilis, Escherichia coli, Staphylococcus aureus and Salmonella typhumurium. At the mixed culture xylooligosaccharides exerted a preferential stimulatory effects on numbers of the health-promoting microorganisms, while xylooligosaccharides inhibited populations of potential pathogens at relatively low level. Xylooligosaccharides also maintained the acidity of culture with Streptococcus mutans, caries-inducing bacteria, over pH 5.0. These results suggest that xylooligosaccharides selectively promote the growth of the health-promoting microorganisms in human intestine and prevent caries by inhibiting acid production from Streptococcu mutans.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.888-896
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• 2014

The effects of sugar substances (oligosaccharide, xylitol and erythritol) as alternative ingredients to sucrose on the quality characteristics and antioxidant activities of aronia jam were evaluated. The different types of sweeteners did not influence the pH, total acidity and sugar contents of the jam. The sucrose-containing jam showed the highest spreadness, while the oligosaccharide and erythritol-containing jams showed lower spreadness. In the chromaticity determination, the sucrose-containing jam showed the lowest L, a and b values compared with the other sweetener groups. There were no significant differences in the total polyphenols, flavonoids and anthocyanin contents in the jams. The antioxidant activity indicated by the DPPH and ABTS radical scavenging activities was over 70%. Sensory evaluation indicated the xylitol-containing jam to have the best preference in taste, flavor and overall acceptance. These results suggested that xylitol may be a good sugar substance in aronia jam.

• Journal of Nutrition and Health
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• v.40 no.sup
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• pp.39-49
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• 2007

본 논문은 미국 의학연구소(US Institute of Medicine, IOM)와 미국 농무성의 식이지침 자문위원회(USDA Advisory Committee on Dietary Guidelines, DG)에서 발표한 권위 있는 종설 들과 미국 영양사협회 학술지를 포함하여 여러 학술지에 발표된 의미 있는 종설 들의 내용을 종합한 것으로 일부의 내용은 그들의 의견을 그대로 반영하였다. 당은 단당류와 이당류를 말하며 당에는 포도당, 과당, 갈락토오즈, 맥아당, 서당과 유당이 포함된다. 당의 식품급원으로는 고과당 옥수수시럽, 사탕수수, 꿀, 사탕수수, 맥아시럽 등이 있다. 당은 미국 식약청에서 일반적으로 안전하다고 인식(generally recognized as safe, GRAS)되고 있다. 당은 에너지를 공급하며, 정신적인 만족감을 부여하는 기능을 가지고 있다. 대부분의 과일과 유제품은 당을 많이 함유하고 있으며, 건강한 식사를 구성하는 식품으로 섭취되고 있다. 당은 또한 조리와 가공과정에서 식품의 맛과 기능적인 면을 향상시키기 위해 첨가되기도 한다. 당은 영양밀도가 높은 식품/음료의 기호성(palatability)를 향상시키므로, 감미료들은 건강한 식사가 되도록 도와줄 수 있다. 그러나 첨가당의 섭취가 증가되면 식사의 영양밀도가 감소하는 가능성에 대한 우려가 있다. 여러 연구에 의하면 첨가당의 섭취가 총 열량 섭취의 25% 이상이 되면 식품의 영양밀도 감소가 나타날 수 있다고 보고하고 있다. 한국에서 추정된 당의 섭취량은 이것보다는 매우 낮은 수준이다. 선진국들에서 당의 섭취가 건강에 부정적인 영향을 줄 수 있다는 가능성에 대해서는 많은 논란이 되고 있다. 그러나 적절한 양을 섭취하는 범위에서 당의 섭취 자체만으로는 비만, 당뇨병, 대사증후군과 고콜레스테롤혈증의 위험이 증가되지 않는다는 과학적인 연구보고들이 있다. 그러므로 IOM은 "여러 자료에 근거하여, 충치, 행동적인 문제, 암, 비만의 위험성과 고지혈증의 위험성에 있어서 총 당과 첨가당에 대한 상한섭취량(tolerable upper limit)을 설정하는 것에 대한 증거가 불충분하다"고 결론을 내리고 있다.