• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1211-1218
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• 2006

The enantiomerically pure (2R,3S)- and (2R,3R)-3-amino-2-hydroxy-4-phenylbutanoic acids (AHPBA) 1 and 3 are readily obtained from D-glucono-a-lactone. Both AHPBAs are the structural key units of KMI derivatives which are the potent inhibitors of BACE 1 ($\beta$-secretase) and HIV protease. Additionally, the obtained AHPBAs 1 and 3 are converted to dipeptides of bestatin stereoisomers 2 and 4.

• 대한가정학회지
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• 제18권2호
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• pp.15-21
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• 1980

Three kinds of soybean curd were prepared with three coagulants such as calcium chloride, magnesium chloride and glucono delta lactone. The mineral contents of the three soybean curds were analyzed before soaking and after various lengths of soaking(1/2 hour, 1 hour, 2 hours, and 2 hours(water changed after 1/2 hour)). Results therefrom were as follows: 1. Before the three soybean cured were soaked, their moisture contents were 79-83g/%. The ash contents were 5.04g% in the soybean curd made with CaCl_{2}4.42g/% in the soybean curd prepared with MgCl_{2} and 3.86g/% in the soybean curd coagulated by glucono delta lactone. an analysis of calcium, magnesium and phosphorous contents showed that each element had a greater concentration in the soybean curds made with divalent mineral salts than in the soybean curd made with acid. 2. Changes taking place in the mineral contents of the soybean curds according to different soaking times were examined. The mineral contents tended to decease in process of soaking time. The soybean curds showed the highest rate of mineral dissolution after one hour of soaking, and then they tended to reabsorb minerals. When the soybean curds were soaked I freshly changed water for one hour and 30 minutes, their mineral contents indicated a greater diminishing trend but no significant difference was noticed among the different kinds of soybean curd. In case coagulant has been used excessively, it is necessary to soak the bean curds for about one hour to get the coagulant dissolved.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1094-1099
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• 1998

Newly introduced aseptic process for cooked rice was optimized by evaluating the process parameters. The optimal conditions were as follows: ratio of washing water to rice, 3:1 by weight; steeping at 20oC for 20min; heat shock at 140oC for 7sec with 8 repetitions; addition of 0.2% glucono lactone solution; cooking at 103oC for 30min. The final products were incubated at 37oC and 50oC for 8 weeks and no spoilage was occurred at both temperatures. Furthermore, any significant losses of sensory and physicochemical qualities were not observed.

• 한국수산과학회지
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• 제12권3호
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• pp.137-141
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• 1979

두부가공조건 및 순두부용 분말의 제조에 관하여 실험하여 다음과 같은 결과를 얻었다. 원료대두이 수침시간으로는 10시간이 적당하였다. 두유의 응고온도로는 $CaSO_4{\cdot}2H_2O,\;MgCl_2{\cdot}6H_2O$ 및 $CaCl_2$의 경우 $80^{\circ}C$가, GDL을 응고제로 사용할 때는 $90^{\circ}C$가 적당하였다. 응고제의 농도로는 $CaSO_4{\cdot}2H_2O,\;MgCl_2{\cdot}6H_2O$ 및 $CaCl_2$의 경우 원료대두에 대하여 $2%$가, GDL은 $3%$가 적당하였다. 수율과 제품의 단백질 함량면으로 보아 GDL의 사용이 $CaSO_4{\cdot}2H_2O,\;MgCl_2{\cdot}6H_2O$ 및 $CaCl_2$의 사용 보다 효과적이었다. 순두부용 분말의 제조는 두유를 분무건조함으로써 가능하였으며, 두유에 크릴즙을 혼합하여 분무건조하여 독특한 색택과 향미를 지닌 순두부용 분말의 제조가 가능하였다. 응고제를 두유와 크릴즙과 함께 혼합, 분무건조하여 순두부제조시 응고제를 달리 사용할 필요가 없는 분말의 제조가 가능하였다.

• Mycobiology
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• 제40권3호
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• pp.173-180
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• 2012

A ${\beta}$-glucosidase from Penicillium italicum was purified with a specific activity of 61.8 U/mg, using a chromatography system. The native form of the enzyme was an 88.5-kDa tetramer with a molecular mass of 354 kDa. Optimum activity was observed at pH 4.5 and $60^{\circ}C$, and the half-lives were 1,737, 330, 34, and 1 hr at 50, 55, 60, and $65^{\circ}C$, respectively. Its activity was inhibited by 47% by 5 mM $Ni^{2+}$. The enzyme exhibited hydrolytic activity for p-nitrophenyl-${\beta}$-D-glucopyranoside (pNP-Glu), p-nitrophenyl-${\beta}$-D-cellobioside, p-nitrophenyl-${\beta}$-D-xyloside, and cellobiose, however, no activity was observed for p-nitrophenyl-${\beta}$-D-lactopyranoside, p-nitrophenyl-${\beta}$-D-galactopyranoside, carboxymetyl cellulose, xylan, and cellulose, indicating that the enzyme was a ${\beta}$-glucosidase. The $k_{cat}/K_m\;(s^{-1}mM^{-1})$ values for pNP-Glu and cellobiose were 15,770.4 mM and 6,361.4 mM, respectively. These values were the highest reported for ${\beta}$-glucosidases. Non-competitive inhibition of the enzyme by both glucose ($K_i=8.9mM$) and glucono-${\delta}$-lactone ($K_i=11.3mM$) was observed when pNP-Glu was used as the substrate. This is the first report of non-competitive inhibition of ${\beta}$-glucosidase by glucose and glucono-${\delta}$-lactone.

• 한국식품과학회지
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• 제29권6호
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• pp.1131-1137
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• 1997

팽창제 종류에 따른 시간별 가스 발생 속도 및 쿠키 텍스쳐에 대하여 살펴보았다. 본 실험에 사용된 가스 발생 장치에 의해서도 가스 발생 속도에 따라 크게 3타입으로 구분할 수 있었으며 이는 소암모늄명반을 제외하고는 문헌의 결과와 일치하였다. 속효성 평창제로는 주석산, 주석영, 후말산, 소암모늄명반이었고 이단 반응성 팽창제로는 산성피로인산나트륨, 무수모노인산칼슘, 소명반이었으며, 지효성 팽창제로는 중탄산암모늄, 중탄산나트륨, 글루코노-델타-락톤, 염화암모늄 등이었다. 제품 팽창률이 가장 높았던 것은 중탄산암모늄이었고 후미 면에서 가장 깨끗한 것은 글루코노-델타-락톤이었다. 팽창률이 높을수록 texture profile graph상에서 multi-peak를 나타내어 brittleness가 뛰어났으며 단순회귀분석에 의해, 팽창률과 brittleness간에 상관관계가 있음을 입증하였다$(r^2=0.8176)$. 중탄산암모늄을 사용한 쿠키 제품의 brittleness가 가장 높았다.

• 한국식품영양과학회지
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• 제33권3호
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• pp.553-559
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• 2004

본 연구에서는 미생물이 생성하는 글루코노델타락톤을 김치에 첨가하여 냉장저장하였을 때, 김치의 초기 pH를 강하시켜 김치의 주발효균인 유산균의 생육을 억제하여 김치의 보존성을 향상시키고 숙성기간을 연장시키고자 하였다. GDL이 첨가된 김치의 초기 pH강하는 GDL이 수용액에서 유기산인 글루콘산으로 전환되면서 나타나는 현상이며 삼투압 작용에 의해 점차 평형을 이루게 되어 pH가 상승하였다가 숙성이 진행되면서 대조구보다 완만하게 pH가 저 하하였다. pH 강하로 인하여 김치의 초기 유산균의 생육이 지연되면서 대조구와 비교시 숙성기간동안 산 생성량이 적게 나타났다. HPLC 분석에서 김치의 발효동안 oxalic acid, succinic acid, lactic acid, malic acid와 acetic acid가 생성되는 것으로 나타났으며, 대조군의 경우 GDL을 첨가한 경우보다 lactic acid의 생성량이 현저히 많았다. 김치에 첨가된 GDL은 초기 주 발효균인 L. mesenteroides의 생육을 억제함으로써 김치의 숙성을 지연시키고, 그 이후의 L. brevis와 산내성 이 강한 L. plantarum의 생육을 억제함으로써 산도의 증가를 지연시키고 김치 조직의 연화를 방지 할 수 있는 것으로 생각된다. 또한, 글루콘산은 무색의 순한 청량한 신맛을 띄는 유기산으로 관능검사에서 김치 고유의 맛과 향기에 영향을 주지 않았다. 따라서, 김치 제조시 GDL의 첨가는 김치의 유산균의 생육지연을 통하여 김치가 숙성에 도달하는 시간을 지연, 유지 시켜 가식 기간을 연장시킬 수 있으면서, 관능적 품질에 차이가 없는 김치를 제조할 수 있었다.

• 한국식품영양학회지
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• 제33권5호
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• pp.576-583
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• 2020

The purpose of this study was to compare the quality characteristics of silken tofu products from the commercial market in Korea. Seven types of commercial silken tofu were sampled and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity, moisture contents (total solid contents), crude protein and fat contents were evaluated. The TPA results suggest that the texture of silken tofu was very different from one another according to the type of and the amount of coagulant. The commercial silken tofu showed a range of pH 5.53~6.48, total acidity of 0.12~0.32%, soluble solid contents of 2.62~5.07 °Brix, salinity of 2.28~4.30%, and moisture contents of 87.10~92.24%, respectively. In terms of the coagulant of tofu, besides the GDL (glucono-δ- lactone), other coagulants such as MgCl₂ for making 'silken tofu' in the Korean tofu market. The quality characteristics differed depending on the constituents of sample and the coagulants of tofu used. These results are expected to be useful in identifying new trends in the domestic silken tofu industry.

• 한국축산식품학회지
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• 제30권5호
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• pp.746-754
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• 2010

Response surface methodology was adopted to model and optimize the effects of microbial transglutaminase (TG) and calcium alginate (CA) systems of various ratios on the gelation characteristics of porcine myofibrillar protein (MP) at various salt levels. The CA system consisting of sodium alginate (SA), calcium carbonate (CC) and glucono-$\delta$-lactone (GdL) showed no remarkable changes in the salt-soluble fraction, and only minor effects on electrostatic interactions were observed. Increasing CA concentration caused acid-induced hydrophobic interactions in MPs, resulting in increased MP gel strength. The TG system, containing TG and sodium caseinate (SC), induced cold-set MP gelation by formation of covalent bonding. The main advantage of the combined system was a higher cooking yield when the MP gel was heated. These results indicated that 0.7% TG combined with 0.8% CA system can form a viscoelastic MP gel, regardless of salt levels.

• Preventive Nutrition and Food Science
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• 제10권3호
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• pp.224-230
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• 2005

The effects of low viscosity chitosan on the rheological properties of soymilk using a model system and on tofu qualities were examined. The flow behavior of soy milk with chitosan closed the Newtonian flow and stabilized according to increasing chitosan concentration. The soymilk containing $glucono-\delta-lactone$ exhibited a more pseudoplastic flow behavior compared with that of the control soymilk. The addition of low viscosity chitosan to the tofu preparation did not significantly affect its physicochemical properties. However, the results of the TEM image and instrumental textural properties showed that low viscosity chitosan affected the construction of the tofu structure. Chitosan tofu had low scores across the whole field of appearance in the sensory evaluation, and its overall eating quality was scored significantly lower. These results suggest that the addition of low viscosity chit os an affects the quality of tofu, which changes according to the degree of polymerization and concentration of chitosan.