• 한국식품과학회지
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• 제36권5호
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• pp.795-799
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• 2004

동아즙을 밀가루에 25, 50, 75, 100% 농도로 첨가하여 제조한 반죽의 리올로지와 이들로부터 제조한 국수의 품질특성을 조사하였다. RVA상의 호화개시온도는 전반적으로 대조구보다 첨가구가 동아즙의 첨가량이 증가함에 따라 상승하였으며 최고점도 및 최종점도는 25% 첨가구를 제외하고는 대조구에 비해 동아즙의 첨가량에 따라 높아지는 경향을 나타내었다. 파리 노그래프상의 수분흡수율 및 반죽의 약화도는 첨가량이 증가함에 따라 증가하였으나 반죽의 형성시간과 안정성은 동아즙의 첨가량에 따라 감소하였다. 제조한 국수의 조리후의 중량, 부피, 고형분 손실량 및 수분흡수율은 모두 동아즙의 첨가량이 증가함에 따라 증가하였다. 조리한 국수의 텍스쳐 측정결과 견고성, 응집성, 검성은 동아즙의 첨가량이 증가할수록 유의적으로 증가하였으나, 탄성 및 씹힘성은 유의적인 차이를 보이지 않았다. 조리한 국수의 관능검사결과, 25 및 50% 첨가구가 모든 항목에서 가장 양호한 것으로 나타났다.

• 한국식품과학회지
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• 제24권2호
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• pp.127-131
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• 1992

밀가루의 리올로지 특성에 대한 염소처리의 영향을 연구하기 위하여 밀가루 100 파운드당 1, 2 및 4 oz의 액화염소가스를 각각 처리하여 각종 리올로지 특성의 변화를 비교하였다. Farinogram 특성에서 departure time, 수분흡수율, 안정도는 염소처리량 증가에 따라 점증적으로 증가하였으나 MTI는 감소하는 경향을 나타냈다. Extensogram 특성에서 염소처리하지 않은 밀가루는 신장도에 비하여 저항도가 큰 반면, 처리량이 1 oz와 2 oz는 적당한 신장도와 저항도를 갖고 있으므로 제빵에 적합한 반죽특성을 가졌다. Amylogram 특성에서 최고점도시 온도는 염소처리량 증가에 따라 거의 직선적으로 높아지는 경향을 나타냈다. 최고점도는 1 oz 처리시 다소 증가하였고 1 oz와 2 oz 처리는 처리량에 따른 변화는 없었다.

• Journal of Microbiology
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• 제40권2호
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• pp.140-145
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• 2002

The 5.8 kb pMMH1, rolling-circle replication (RCR) plasmid of the wild type soil Bacillus mesentericus was developed into a novel secretion vector system in Bacillus subtilis. The pMMHl turned out to have a replication origin and two open reading frames (ORFs) of the putative γ-GTP and type I signal peptidase (sipP). To characterize the regions necessary for plasmid stability and high copy number, five vectors (pPS, pPP, pEN, pMN, pME) were constructed by disruption or deletion of each region in pMMH1. Like pMMHl all constructed vectors were stable over 100 generations In a non-selective medium. Since pPS was the smallest (2.3 kb)of all, it was selected for the construction of a navel secretion vector, Using the $\alpha$-amylase promoter/signal sequence of B. subtilils the novel plasmid pJSN was constructed. When $\beta$-glucosidase was expressed using pJSN, we found $\beta$-glucosidase activity in the medium. This result strongly suggested that plasmid pJSN can be used for the production of bioactive peptides in B. subtilis.

• 한국식품과학회지
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• 제18권3호
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• pp.192-196
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• 1986

쌀보리 품종인 송학과 명산 전분의 NaOH(0.14${\sim}$0.21N)및 KSCN(1.5${\sim}$4.5M)에 의한 화학적 호화 특성을 비교하였다. 알칼리(NaOH)에 의한 호화시 전분 현탄액의 광투라도는 영산 전분에 비해 송학 전분이 낮은 값을 보엿다. 또한 점도는 여러 전분 농도(5${\sim}$12.5%)에서 영산 전분이 높은 값을 보였으며, 전분의 호화에 필요한 알칼리의 농도는 영산 전분이 송학 전분보다 0.1meq NaOH/g정도 낮았다. 두 전분 모두 일정한 전분 농도에서의 초기호화속도는 알칼리 농도가 증가함에 따라 기울기가 서로 다른 두개의 직선관계를 보였다. 그러나 동일알칼리 농도에서는 전분의 농도가 증가할수록 초기화화 속도는 직선적으로 감소하였다. 전분 겔의 부피는 두 전분 모두 2.5M KSCN에서 최고값을 보였으나, 영산 전분이 송학 전분보다 겔의 부피가 컸으며 겔의 안정성은 약하였다.

• 한국식생활문화학회지
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• 제29권4호
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• pp.355-363
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• 2014

The purpose of this study was to investigate the rheological characteristics of medium wheat flour mixed with bamboo leaf and lotus leaf powders. Rheological properties of the mixed flours were tested based on falling number, color, RVA, farinogram, and rheofermentometer analyses. Falling numbers increased with addition of bamboo leaf and lotus leaf powders. The L values of all mixed flours were less than that of control. The 1% mixed flour sample containing bamboo leaf and lotus leaf powders was not significantly different from 3% mixed flour. The a values of the mixed flour decreased as bamboo and lotus powders increased, whereas b values increased. Addition of bamboo leaf and lotus leaf powders to flour reduced peak viscosity, holding strength, and final viscosity. The set back values of mixed wheat flour containing bamboo leaf powder were lower than those of mixed wheat flour containing lotus leaf powder, suggesting that bamboo leaf powder suppressed retrogradation of flour compared to lotus leaf powder. In the farinogram, the water absorption and consistency of the flours containing bamboo and lotus leaf powders increased, whereas development time and stability decreased. The fermentation time of dough with lotus leaf powder was less than that of dough with bamboo leaf powder.

• Food Science and Biotechnology
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• 제14권3호
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• pp.317-322
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• 2005

A simple and convenient method of immobilizing dextransucrase via an affinity interaction is described, along with the use of this system to synthesize leucrose. Dextransucrase was produced in sucrose-free medium by fermenting a constitutive mutant of Leuconostoc mesenteroides NRRL B-512F and was separated using an ultrafiltration membrane. The purified enzyme was free of dextran polymer, which previously was always found with the sucrose-induced enzyme. Therefore, it was possible to immobilize the enzyme on dextran-based resins using an affinity interaction. Sephadex G-200 was the best resin for immobilizing the dextransucrase and gave a fast flow rate through the packed column. The immobilized dextransucrase retained more than 80% of its specific activity after immobilization ($K_m\;=\;18.1\;mM$ and $k_{cat}\;=\;450\;sec^{-1}$ vs. 13.1 mM and $640\;sec^{-1}$, respectively, for the free enzyme). The immobilized dextransucrase showed improved stability over a pH range of 4.0 to 6.5 and at moderately high temperatures over $40^{\circ}C$. When immobilized dextransucrase was used to synthesize leucrose via the transfer reaction with sucrose and fructose, about 74% of the sucrose was converted into leucrose after one day, and the half-life of the enzyme activity was 15 days. Regeneration of the resin by supplementation with dextransucrase enabled the recovery of the initial activity of the system, but both the reaction and the flow rate were lower, probably owing to the accumulation of dextran inside the resin.

• 방사선산업학회지
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• 제5권1호
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• pp.21-24
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• 2011

This study was conducted to evaluated the sensory properties of Miyukgook, Korean seaweed soup, with gamma-irradiated Undaria pinnadifida for enhancing the storage of the harvested seaweed. The harvested seaweed was irradiated at the doses of 1, 3, 5, and 10 kGy. The Miyukgook was made by following the general recipe. The values of pH and acidity of the Miyukgook were not changed by the irradiation of harvested Undaria. The sensory evaluation result showed that the preference scores in all the sensory properties was a little decreased when it was irradiated, but sensory score of less than 5 kGy samples was similar in all terms. Therefore, it was considered that gamma irradiation with less than 5 kGy was effective for improvement of the storage stability of U. pinnatifida without the changes in the sensory of its major cooked food, Miyukgook.

• Asian-Australasian Journal of Animal Sciences
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• 제32권7호
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• pp.977-987
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• 2019

Objective: The use of tannin extract and other phytochemicals as dietary additives in ruminants is becoming more popular due to their wide biological actions such as in methane mitigation, bypass of dietary protein, intestinal nematode control, among other uses. Unfortunately, some have strong astringency, low stability and bioavailability, and negatively affecting dry matter intake and digestibility. To circumvent these drawbacks, an effective delivery system may offer a promising approach to administer these extracts to the site where they are required. The objectives of this study were to encapsulate acacia tannin extract (ATE) with native starch and maltodextrin-gum arabic and to test the effect of encapsulation parameters on encapsulation efficiency, yield and morphology of the microparticles obtained as well as the effect on rumen in vitro gas production. Methods: The ATE was encapsulated with the wall materials, and the morphological features of freeze-dried microparticles were evaluated by scanning electron microscopy. The in vitro release pattern of microparticles in acetate buffer, simulating the rumen, and its effect on in vitro gas production was evaluated. Results: The morphological features revealed that maltodextrin/gum-arabic microparticles were irregular shaped, glossy and smaller, compared with those encapsulated with native starch, which were bigger, and more homogenous. Maltodextrin-gum arabic could be used up to 30% loading concentration compared with starch, which could not hold the core material beyond 15% loading capacity. Encapsulation efficiency ranged from $27.7%{\pm}6.4%$ to $48.8%{\pm}5.5%$ in starch and $56.1%{\pm}4.9%$ to $64.8%{\pm}2.8%$ in maltodextrin-gum arabic microparticles. Only a slight reduction in methane emission was recorded in encapsulated microparticles when compared with the samples containing only wall materials. Conclusion: Both encapsulated products exhibited the burst release pattern under the pH conditions and methane reduction associated with tannin was marginal. This is attributable to small loading percentages and therefore, other wall materials or encapsulation methods should be investigated.

• Korean Journal of Chemical Engineering
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• 제35권11호
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• pp.2207-2219
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• 2018

Activated carbon (AC) was synthesized from Phoenix dactylifera stones and then modified by $CoFe_2O_4$ magnetic nanocomposite for use as a Cr(VI) adsorbent. Both $AC/CoFe_2O_4$ composite and AC were fully characterized by FTIR, SEM, XRD, TEM, TGA, and VSM techniques. Based on the surface analyses, the addition of $CoFe_2O_4$ nanoparticles had a significant effect on the thermal stability and crystalline structure of AC. Factors affecting chromium removal efficiency like pH, dosage, contact time, temperature, and initial Cr(VI) concentration were investigated. The best pH was found 2 and 3 for Cr adsorption by AC and $AC/CoFe_2O_4$ composite, respectively. The presence of ion sulfate had a greater effect on the chromium sorption efficiency than nitrate and chlorine ions. The results illustrated that both adsorbents can be used up to seven times to adsorb chromium. The adsorption process was examined by three isothermal models, and Freundlich was chosen as the best one. The experimental data were well fitted by pseudo-second-order kinetic model. The half-life ($t_{1/2}$) of hexavalent chromium using AC and $AC/CoFe_2O_4$ magnetic composite was obtained as 5.18 min and 1.52 min, respectively. Cr(VI) adsorption by AC and $AC/CoFe_2O_4$ magnetic composite was spontaneous and exothermic. In general, our study showed that the composition of $CoFe_2O_4$ magnetic nanoparticles with AC can increase the adsorption capacity of AC from 36 mg/L to 70 mg/L.

• 한국축산식품학회지
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• 제43권2호
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• pp.245-268
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• 2023

The effects of phosphate alternatives on meat quality in marinated chicken were investigated with the application of chilling and freezing. Breast muscles were injected with solution of the green weight containing 1.5% NaCl and 2% sodium tripolyphosphate (STPP) or phosphate alternatives. Treatment variables consisted of no phosphate [control (-)], 0.3% sodium tripolyphosphate [control (+)], 0.3% prune juice (PJ), 0.3% oyster shell, 0.3% nano-oyster shell, and 0.3% yeast and lemon extract (YLE) powder. One-third of the meat samples were stored at 4℃ for 1 d, and the rest of the meats were kept at -18℃ for 7 d. In chilled meat, a lower drip loss was noted for control (+) and YLE, whereas higher cooking yield in YLE compared to all tested groups. Compared with control (+), the other treatments except PJ showed higher pH, water holding capacity, moisture content, lower thawing and cooking loss, and shear force. Natural phosphate alternatives except for PJ, improved the CIE L^* compared to control (-), and upregulated total protein solubility. However, phosphate alternatives showed similar or higher oxidative stability and impedance measurement compared to control (+), and an extensive effect on myofibrillar fragmentation index. A limited effect was observed for C^*, h°, and free amino acids in treated meat. Eventually, the texture profile attributes in cooked of phosphate alternatives improved except for PJ. The results indicate the high potential use of natural additives could be promising and effective methods for replacing synthetic phosphate in chilled and frozen chicken with quality enhancement.