• Title/Summary/Keyword: pH stability

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Quality Characteristics of White Bread added Modified Starch (변성 전분을 첨가한 식빵의 품질 특성)

  • Kim, Hyo Suk;Lee, Seung Joo;Lee, Seung Ju
    • Journal of the East Asian Society of Dietary Life
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    • v.25 no.3
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    • pp.474-483
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    • 2015
  • The textural properties of breads containing midified starches such as pregelatinized waxy corn starch, acetylated potato starch and hydroxypropylated tapioca starch, were investigated to determine the optimum addition level of modified starches. Effects of modified starches on dough properties were investigated through a farinogram and amylogram based on the different additional levels of modified starches (3%, 6%, 9%, 12% and 15% of flour content). Moisture contents and firmness values were measured to investigate the degree of retrogradation at 0 h, 36 h and 72 h after production. The levels of moisture contents were highest upon addition of pregelatinized waxy corn starch followed by acetylated potato starch and lowest upon addition of hydroxypropylated tapioca starch. Overall, higher moisture contents resulted in lower firmness levels. The preference scores by type of modified starch were highest upon addition of 9% hydroxypropylated tapioca starch, 3% pregelatinized waxy corn starch, and 6% acetylated potato starch, respectively. Preference scores were significantly correlated with textural properties such as volume, absorption, stability and weakness (p<0.01).

A Trend in Research and Development of Natural Gardenia Pigments (천연 치자 색소의 연구개발 동향)

  • Shin, Hyun-Jae
    • KSBB Journal
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    • v.22 no.5
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    • pp.271-277
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    • 2007
  • Natural pigments have many applications like colouring agent, pigments, food additives, and antiseptics. At present, instead of synthetic pigments that have contributed to the development of industry, many kinds of natural pigments have been developed. The constituents of gardenia fruits, Gardenia jasminoides ELLIS, are traditionally known as herb medicine and natural dyes/pigments due to the customer is needs. The fruits produce yellow carotenoid pigments and iridoid compounds. The two main components in the yellow pigments are called crocin and crocetin. The extraction mode of yellow pigment from Gardenia is depended upon the extraction time, temperature, and volume of solvent. Red pigments or blue pigments formed from geniposide and amino acids have been reported a lot. Geniposide, the principal iridoid glucoside contained in gardenia fruit, was hydrolyzed to genipinic acid or genipin as a precursor for the pigment by enzymatic or chemical reaction. These red or blue pigments prepared with materials hydrolyzed of geniposide and amino acid and had properties governed by the electrostatic character of the amino acid. The pigments showed good stability to heat and pH but were gradually bleached by light while the other natural pigments are unstable in light, heat, acid, and base solution. The safety of the pigments was considered to be of little virulences in comparison to synthetic pigments.

Physical Properties of Dough with Bamboo Leaf Powder (죽엽 분말을 첨가한 반죽의 물리적 특성)

  • Hwang, Su-Jung
    • Food Science and Preservation
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    • v.18 no.4
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    • pp.517-526
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    • 2011
  • The physical properties of dough with different levels (2, 4, 6, and 8%) of bamboo leaf powder were inverstigated. The bamboo leaf powder had a moisture content of 5.15%, a crude protein content of 10.48%, a crude fat content of 5.21%, a crude fiber content of 22.74%, and a crude ash content of 17.63%. The following parameters showed significant differences with the increase in the amount of bamboo leaf powder added. The gelatinization degree measured by a rapid visco-analyzer increased with the increase in the powder amount added. In the values of the farinogram parameter for dough consistency, the elasticity of the dough increased with the increase in the powder amount added. The alveogram values showed a similar tendency as those of the farinogram in terms of elasticity, absorption rate, absorption time and stability. In the rheofermentometer analysis, the volume decreased with the increase in the powder amount added, but no significant difference was found at up to 4% powder amount addition, suggesting that the about 2% and up to 4% powder amount addition is moderate.

On the Decomposition of Dimethyl-2, 2-dichlorovinylphosphate (Dimethyl-2, 2-dichlorovinylphosphate의 분해반응에 관한 연구)

  • Sung, Nack-Do;Park, Seung-Heui
    • Applied Biological Chemistry
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    • v.26 no.2
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    • pp.125-131
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    • 1983
  • Formal net charges, bond populations, atomic orbital coefficients, energy components and conformation of dimethyl-2,2-dichlorovinylphosphate have been studied theoretically by using the CNDO/2 molecular orbital calculation method in attempt to describe the reactivity and the stability of the molecule. From the analysis of rate equation, molecular orbital calculations and identification of the hydrolysis products, 2,2-dichloroacetaldehyde and dimethylphosphoric acid, a mechanism of the hydrolysis of dimethyl-2,2-dichlorovinylphosphate(DDVP) has been proposed. The hydrolysis of DDVP proceeds through the mechanism of nucleophilic addition, typical Micheal reaction in basic media. Therefore, it appears probable that the attack by strong nucleophile, hydroxide ion occurs at the increased positive charge $C_2({\alpha})$ atom of a staggered conformation due to the inductive effect (-)I>(+)R of 2,2-dichlorovinyl, electron-attracting group. And then, the hydrolytic scission involves the $C_2({\alpha})-O_3$, ${\pi}-anti-bonding\;orbital({\pi}^*)$ in the subsequent reaction in aqueous solution.

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Determination of Inorganic Phosphate in Paprika Hydroponic Solution using a Laboratory-made Automated Test Stand with Cobalt-based Electrodes (코발트전극과 자동시험장치를 이용한 파프리카 양액 내 무기인산 측정)

  • Kim, Hak-Jin;Son, Dong-Wook;Kwon, Soon-Goo;Roh, Mi-Young;Kang, Chang-Ik;Jung, Ho-Seop
    • Journal of Biosystems Engineering
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    • v.36 no.5
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    • pp.326-333
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    • 2011
  • The need for rapid on-site monitoring of hydroponic macronutrients has led to the use of ion-selective electrodes, because of their advantages over spectrophotometric methods, including simple methodology, direct measurement of analyte, sensitivity over a wide concentration range, and low cost. Stability and repeatability of response can be a concern when using multiple ion-selective electrodes to measure concentrations in a series of samples because accuracy might be limited by drifts in electrode potential. A computer-based measurement system could improve accuracy and precision because of both consistent control of sample preparation and easy calibration of sensors. Our goal was to investigate the applicability of a cobalt-based electrode used in conjunction with a laboratory-made automated test stand for quantitative determination of ${PO_4}^-$ in hydroponic solution. Six hydroponic solutions were prepared by diluting highly concentrated paprika hydroponicsolution to provide a concentration range of 1 to 300 ppm $PO_4$-P. A calibration curve relating electrode response to phosphate in paprika hydroponic solution titrated to pH 4 with 0.025M KHP was developed based on the Nikolskii-Eisenman equation with a coefficient of determination ($R^2$) of 0.94. The laboratory-made test stand consisting of three cobalt-based electrodes measured phosphate concentrations similar to those obtained with standard laboratory methods (a regression slope of 0.98 with $R^2$ = 0.80). However, the y intercept was relatively high, 30 ppm, probably due to the relatively large amount of variation present among multiple measurements of the same sample. Further studies on the high variation in EMFs obtained with cobalt electrodes during replicate measurements were required for P estimations comparable to those obtained with standard laboratory instruments.

Food Functionality and Bioactivity of Vacuum Freeze-dried Fish Roe Concentrates (동결건조 어류 알 농축물의 식품기능성 및 생리활성)

  • Yoon, In Seong;Kim, Hyeung Jun;Kang, Sang In;Kim, Do Youb;Lee, Chang Young;Jeong, U-Cheol;Kim, Jin-Soo;Heu, Min Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.53 no.3
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    • pp.403-416
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    • 2020
  • The purpose of this study was to evaluate the food functional properties and in vitro bioactivity of vacuum freeze-dried fish roe concentrates (FRCs) prepared from Alaska pollock Theragra chalcogramma (AP), bastard halibut Paralichthys olivaceus (BH) and skipjack tuna Katsuwonus pelamis (ST). All three species showed better buffering capacity on the alkaline side (pH 10-12) than on the acidic side. The water-holding capacities of the FRCs were 3.5, 8.5 and 4.2 g/g protein for AP, BH and ST, respectively, and were significantly higher than that of commercial egg white. The protein solubilities of the FRCs were 42.5% (AP), 50.0% (BH) and 13.9% (ST). The foaming capacities of the FRCs were not significantly different among the species (128.0% for AP, 128.3% for BH, and 143.3% for ST; P>0.05), and their foam stability was maintained at 53.0-74.2% for 60 minutes. The oil-in-water emulsifying activity indexes of AP and BH (19.5 and 20.2 ㎡/g protein, respectively) were significantly superior to that of ST (P<0.05). The 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothia-zoline-6-sulfonic acid radical-scavenging activities (IC50, mg/mL) of the FRCs were in the ranges of 1.05-3.26 and 0.13-0.18 mg/mL, respectively, and the angiotensin I converting enzyme inhibitory activity was in the range of 0.97-1.89 mg/mL.

Effect of Ozone Treatment for Sanitation of Egg (계란의 위생화를 위한 오존살균기술의 이용)

  • Choi, Goo-Hee;Lee, Kyung-Haeng
    • Food Science of Animal Resources
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    • v.32 no.2
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    • pp.198-203
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    • 2012
  • To improve hygienic quality of egg, the ozone treatment was applied. Eggs were inoculated with Salmonella Typhimurium, and the inoculated eggs were treated by ozone (38.8 ppm) for 10-30 min. Furthermore, microbiological and chemical quality changes of eggs were investigated during storage. Initial number of S. Typhimurium of egg shell was 6.18 log CFU/g and the number was increased during storage (p<0.05). However, those of ozonated samples for 10-30 min were 4.22-5.25 log CFU/g, which was lower than that of the control. Especially, ozone treatment for 30 min achieved about 2 decimal reductions and the numbers were maintained during storage. Other physical and chemical characteristics of eggs by ozone treatment, including Haugh unit, yolk color, pHs of egg white and yolk, foaming ability, foam stability and lipid oxidation development were not different when compared with that of the control. Therefore, ozone treatment is one of the available methods to improve hygienic quality of eggs.

Effects of Red and Green Glassworts (Salicornia herbacea L.) on Physicochemical and Textural Properties of Reduced-salt Cooked Sausages

  • Kim, Hyun-Wook;Hwang, Ko-Eun;Song, Dong-Heon;Kim, Yong-Jae;Ham, Youn-Kyung;Yeo, In-Jun;Jeong, Tae-Jun;Choi, Yun-Sang;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.34 no.3
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    • pp.378-386
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    • 2014
  • This study was conducted to determine the effects of red and green glasswort on the physicochemical and textural properties of reduced-salt cooked sausages. The control was formulated with 1.5% NaCl; then, three reduced-salt treatments were prepared, with 0.75% NaCl (RS), 0.75% NaCl+1.0% red glasswort (RSR) and 0.75% NaCl+1.0% green glasswort (RSG), respectively. The addition of glasswort within the added amount of 1% had no influence on the pH value of the reduced-salt cooked sausages, regardless of the glasswort type. In terms of color, RSG treatment conveyed a higher hue angle value than the RSR treatment (p<0.05). Increases in the protein solubility (total and myofibrillar proteins) and apparent viscosity of reduced-salt meat batter that were due to the addition of glasswort were observed; however, there were no differences according to the type of glasswort (p>0.05). Furthermore, the addition of glasswort, regardless of its type, resulted in decreased cooking loss, and increased emulsion stability. As a result, reduced-salt cooked sausages formulated with either red or green glasswort demonstrated similar textural properties to those of the control. In conclusion, the type of glasswort within an added amount of 1% had no influence on the physicochemical and textural properties of reduced-salt cooked sausages, except for the color characteristics. In terms of color alteration by the addition of glasswort, the red glasswort, which in comparison with the green glasswort could minimize the color changes of reduced-salt cooked sausages, might be an effective source for manufacturing meat products.

Comparison of the Modified Brostrom Repair Technique with and without Augmentation Using Suture Tape for Chronic Ankle Instability (만성 족관절 불안정성을 가진 환자군에서 변형 브로스트롬 술식과 봉합 테이프를 추가한 술식 간의 결과 비교)

  • Gwak, Heui-Chul;Jung, Soo-Hwan;Kim, Jung-Han;Park, Dae-Hyun;Choo, Hye-Jung;Kim, Dae-Yoo
    • Journal of Korean Foot and Ankle Society
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    • v.26 no.1
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    • pp.40-47
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    • 2022
  • Purpose: The modified Broström repair (BR) technique has yielded good outcomes in patients with chronic ankle instability. This study compared clinical and radiological outcomes between two groups of patients who underwent modified BR or lateral ligament augmentation using suture tapes (ST). Materials and Methods: Seventy-seven patients (ST group [n=47], BR group [n=30]; body mass index <26.61 kg/m2; mean age, 30.7±11.0 years [range, 17~39 years]; mean follow-up, 34.0±12.0 months [range, 24~59 months]) were retrospectively reviewed between January 2014 and July 2017. The Foot and Ankle Outcome Score (FAOS), American Orthopedic Foot and Ankle Score (AOFAS), Foot and Ankle Ability Measure (FAAM), visual analogue scale (VAS) score, and Sefton grading system were used for clinical assessment. The talar tilt angle and anterior talar translation were measured using the Telos stress device (Telos GmbH, Marburg, Germany) at 150 N for radiological evaluation. Results: FAOS, AOFAS, FAAM, and VAS scores improved in both groups at final follow-up (ST, 91.1±5.2, 93±2, 88.1±4.5, 1.5±0.7 vs. BR, 91.3±5.4, 93±3, 83.3±4.8, 1.2±0.7, respectively; p=0.854, 0.971, <0.001, 0.04, respectively). According to the FAOS, mean sports activity scores for the ST and BR groups at the final follow-up were 90.3±3.2 and 76.6±4.2, respectively, reflecting superior outcomes in the ST group (p<0.001). Sefton grading revealed satisfactory functional outcomes (ST, 91.5% vs. BR, 90.0%). There was significant improvement in the talar tilt angle and anterior talar translation in both the ST and BR groups (7.6°±1.2°, 10.5±1.8 mm vs. 4.9°±1.1°, 7.9±1.5 mm, respectively; p<0.001). Conclusion: The ST group demonstrated comparable clinical but better improvement in mechanical stability and FAOS sports scores than the BR group.

Stability of Aminophylline, Ceftriaxone Sodium and Ampicillin/Sulbactam in Total Parenteral Nutrient Solution (고영양수액제 중 아미노필린, 세프트리악손 및 암피실린/설박탐의 안정성에 관한 연구)

  • Cho, Young Ah;Oh, Junghyun;Moon, Hongseop;Choi, In;Choi, Junshik;Gwak, Hye Sun
    • Korean Journal of Clinical Pharmacy
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    • v.14 no.2
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    • pp.96-99
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    • 2004
  • Aminophylline, ceftriaxone 및 ampicillin/sulbactam (Unasyn)을 미숙아용 고영양수액제에 직접 첨가하거나 Y-site로 투여하는 경우의 안정성에 관해 조사하였다. Aminophylline 주사액 (25mg/mL) $300{\mu}l$와 ceftriaxone sodium (37.5 mg/mL) 2mL를 각각 고영양수액제 직접 첨가하였다. 또한 Y-site에서의 안정성 조사를 위해 ceftriaxone sodium (37.5 mg/mL)을 고영양수액제에 각각 1:1 및 1:2 부피비가 되도록 혼합하였고 Unasyn (25mg/mL)은 고영양수액제와 1:1의 부피비로 혼합하였다. 이상과 같이 조제한 혼합액을 $25^{\circ}C$$4^{\circ}C$에 보관하여 aminophylline은 48시간 동안 그리고 항생제들은 24시간 동안의 경시변화를 HPLC를 이용하여 분석하였다. Aminophylline은 위 보존조건에서 48시간동안 안정하였다(변화율 <$10{\%}$). Ceftriaxone sodium을 고영양수액제에 직접 첨가한 경우 ceftriaxone의 잔존률은 $25^{\circ}C$에서 4시간째에 $90.5{\pm}1.8{\%}$이었고 $4^{\circ}C$에는 $95.1{\pm}1.4{\%}$로 측정되었다. Y-site에서의 안정성과 관련하여 ceftriaxone sodium을 고영양수액제와 1:1로 혼합한 경우 양 보존조건에서 ceftriaxone은 24시간 동안 안정하였으나 1:2로 혼합한 경우에는 $4^{\circ}C$ 보관 시에만 안정하였고 $25^{\circ}C$에서는 24시간째에 약 $14{\%}$ 정도 분해되는 것으로 나타났다. 한편, Unasyn의 경우 ampicillin은 24시간째에 $4^{\circ}C$ 보관 시에만 안정하였고 $25^{\circ}C$에서는 24시간째에 약 $14{\%}$정도 분해되는 것으로 나타났다. 한편, Unasyn의 경우 ampicillin은 24시간째에 $4^{\circ}C$에서는 안정하였으나 $25^{\circ}C$에서는 $30{\%}$까지 감소되는 것으로 분석되었고 sulbactam은 24시간째에 온도와 관계없이 안정한 것으로 나타났다. Ceftriaxone sodium을 TPN과 Y-site 혼합 후 1-2시간 이내에 침천이 형성되었고 Unasyn의 경우에는 12시간째에 침천이 형성되었다. 혼합액의 pH나 색상은 연구기간 동안 일정하였다. 이러한 연구결과에 기초할 때, aminophylline은 고영양수액제와 혼합가능하고 ceftriaxone과 Unasyn은 고양양수액제와 혼합시 최소 1시간 동안은 안정한 것으로 평가되었다.

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