• 농업과학연구
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• 제45권1호
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• pp.19-27
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• 2018

To study the effect of natural anti-microbial chemicals on the growth and quality of chili peppers, chitosan ($100mg/L^{-1}$), stevia ($250mg/L^{-1}$), and the mixture of both chemicals at the same concentration were sprayed after planting at 1-week interval throughout the experimental period. Plant height was measured twice after the $3^{rd}$ and $4^{th}$ applications. Plant height was numerically reduced in all chemical treatments compared to that of untreated control; however, there was no statistical difference between treatments. The fruit quality was examined at commercial maturity, and only minor differences were found in fruit color, length, and dry matter content between the treatments. Although a statistical difference was not present for soluble sugars levels, total phenolics, and capsaicin contents, yield in all chemical treatments significantly increased compared to untreated control. The effect on yield increase was greater at the late harvest season regardless of treatments. Total yield of 4 harvests was higher for the chitosan treatment than other treatments. During the experiment, the entire experimental field was waterlogged for 1 day due to sudden heavy rainfall, which resulted in the occurrence of bacterial browning disease in all treatments. The rate of disease occurrence and the degree of severity, however, were much lower in the chitosan treatment. In conclusion, the potential of chitosan as an alternative antimicrobial agent was confirmed in chili peppers in this study. Further research is required on stevia as an alternative chemical for disease control in chili peppers.

• 한국식품영양학회지
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• 제30권6호
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• pp.1176-1183
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• 2017

This study was investigated the quality characteristics and antioxidant of dried Dioscorea bulbifera with various pre-soaking concentrations of oligosaccharide. Dioscorea bulbifera are prepared by additions of 0, 4, 6, 8 and 10% oligosaccharide solution, and dried at $50^{\circ}C$. The effects of pre-soaking percent of Dioscorea bulbifera slices were evaluated by the moisture, soluble solid, pH, titratable acidity, color, browning degree, texture, antioxidant activities and sensory test. According to the percent of pre-soaking oligosaccharide solution was increased, the moisture was increased but soluble solids and titratable acidity were decreased. With respect to the result of colors, Dioscorea bulbifera slices that underwent the 10% pre-soaked process (85.86%) were lighter than control (73.88%). However, the redness and yellowness scores were the lowest than control. The springiness and cohesiveness of texture showed no significant differences among all groups. Gumminess and chewiness of texture results were increased according to per-soaking concentration increase. Also the polyphenol, flavonoid and DPPH (${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activities were significantly increased with increasing immersion concentration. The Dioscorea bulbifera slices supplemented with 6% pre-soaking oligosaccharide solution treatment showed the highest total sensory score. The results of our study indicated that when pre-soaking oligosaccharide solution is used to immerse the Dioscorea bulbifera slice, it has browning inhibition and antioxidant effect.

• 한국식품과학회지
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• 제31권1호
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• pp.128-137
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• 1999

현재 조미료 및 부침가루로 사용되고 있는 표고버섯분말을 사용하여 열풍건조, 진공건조, 동결건조를 이용하여 건조를 행하였다. 각 건조 방법별로 표고버섯분말은 조직구조 및 물리적 특성치인 pore size도 다르게 나타났다. 또한 건조 방법별로 품질 분석을 한 결과 일반성분에서는 초기 수분함량에서 다소 차이가 있었으나 전체적인 차이는 크게 나지 않았다. 또한 건조 표고버섯의 맛 성분인 핵산을 분석한 결과에서도 큰 차이를 나타내지 않았으며, 총페놀 함량에서도 유사한 결과를 나타냈다. 이러한 결과를 토대로 표고버섯 분말의 흡습특성을 조사한 결과 pore size가 가장 큰 동결건조에서 가장 높은 흡습량을 가져왔으며, pore size의 크기에 따라 진공건조, 열풍건조 순으로 흡습량이 많았다. 그리고 저장 온도별로는 가장 낮은 온도인 $5^{\circ}C$에서 가장 높은 흡습을 보여주었으며, $35^{\circ}C$에서는 흡습량이 상대적으로 낮았다. 그러나 $35^{\circ}C$ 상대 습도 84%의 저장온도에서는 진공건조 및 동결건조 시료에서 저장 11일만에 곰팡이가 생겨났으므로 평형수분함량을 측정하지 못하였다. 저장 적정 수분함량을 구하기 위해 단분자층 수분함량을 구한 결과는 동결건조한 시료가 다른 시료보다 높은 값을 나타내었고, 흡습 엔탈피는 동결건조한 것이 가장 높은 값을 보여주었다. 또한 표고버섯분말의 평형수분함량 예측을 위해 현재까지 가장 적합성이 높다는 여러 가지 식으로 적합성을 살펴본 결과 단백질 함량이 비슷한 Khun식과 Mizrahi 식이 적합성이 가장 높았다. 그러나 이러한 식들은 상대습도만으로 구한 값이므로 상대습도뿐만 아니라 온도 및 공극을 변수로 넣어 회귀식을 도출한 결과 $R^2$가 0.989의 적용도가 높은 식을 구하였다.

• 한국균학회지
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• 제14권4호
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• pp.257-263
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• 1986

리그닌 분해기작을 연구하기 위한 일환으로 느타리버섯균(Pleurotus ostreatus) 3종류와 구름버섯균(Poly-porus versicolor)의 리그닌 분해능을 Simple plate test방법으로 비교한 결과 느타리버섯균주 3과 구름버섯균이 가장 큰 clear zone을 나타냈다. 리그닌의 탈중합화 정도를 조사하기 위해서 리그닌배지에 여러가지 탄수화물들을 첨가하여 배양한 후 컬럼크로마토그라피를 해본 결과 4균주 중 느타리균주 2와 3이 첨가된 탄수화물에 대한 탈중합화 효과가 컸고 탄수화물별로는 glucose. cellobiose 및 xylose를 첨가한 경우가 탈중합화 정도가 컸다. 같은 배양액을 UV scanning시 나타나는 파장 280 nm에서의 peak 높이를 비교해 보면 느타리 균주 2가 glucose, cellobiose 그리고 hemicellulose계 탄수화물인 xylose를 첨가한 배지에서 peak가 나타나지 않았고 배양액의 색깔을 보면 리그닌만 넣고 배양한 경우는 갈변현상을 나타냈는데 반해 탄수화물을 첨가한 경우 특히 glucose, cellobiose 및 xylose는 탈색이 심하게 일어났다. 이상의 결과에서 볼 때 리그닌 분해시에 보조기질로 다른 탄수화물을 첨가하면 리그닌의 탈중합화와 갈변현상이 감소되며 리그닌분해정도가 향상된다는 것을 알 수 있다.

• 한국식품저장유통학회지
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• 제22권3호
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• pp.314-321
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• 2015

반건시의 활용성 증대를 위하여 당액침지형 반건시를 제조하였으며 당 조성에 따른 반건시의 이화학적 특성 및 갈변 저해 효과를 검토하였다. 명도와 채도는 S5(sugar 5%), S10(sugar 10%)에서 높았고 그 이상의 농도에서는 감소하는 경향을 나타내었다. 총당, 환원당 및 유리당 함량은 당의 농도가 증대될수록 증가하였으며, S5는 대조구에 비해 감소하는 경향을 나타내었으나 S10은 유사한 함량을 보였으며 S15 및 S20의 경우 과실에 함유하는 당의 농도가 증가하는 것으로 나타났다. 당액침지형 반건시와 갈변효소간의 관계를 알아보기 위해 폴리페놀 산화효소와 과산화효소를 측정하였으며, 당액 농도가 증대됨에 따라 활성이 저해하는 경향을 나타냈고 S10 이후부터는 유사한 활성을 보였다. 폴리페놀, 플라보노이드, 프로안토시아니딘 및 비타민 C 함량은 다른 처리구와 비교하면 S10이 가장 높은 함량을 보여 식품과 당액 사이에 삼투압 때문에 당액으로 용출되는 함량이 감소하는 것으로 나타났다. DPPH 라디칼 소거활성은 S10에서 65.34%로 가장 높은 활성을 나타내었다. 이상의 결과 당액침지 시 삼투작용으로 적정 농도의 확립이 요구되며 갈변억제 및 영양적인 가치 등의 품질특성을 고려하였을 때 10% 설탕을 첨가한 당액 침지법이 반건시 가공품을 제조하는 데 있어 효과적인 방안이 될 것으로 생각된다.

• 한국식품영양과학회지
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• 제23권4호
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• pp.604-613
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• 1994

Hydrophilic brown pigments(HBPs) produced during fermentation and aging the domestic Meju and Doenjang were separated by dialysis and chromatography , and their antioxidant activity were measured . The chemical properties of HBP were determined by UV and IR spectrophotometry. HBPs contents were found to be 93.1 mg/g and 183.2mg/g in Meju fermentated for 30 days and 80 days , respectively. The ratio of dialysate to diffusate of the HBPs were appeared to be 70 : 30 and 87 :13 in the Meju fermented for 30 days and 80 days, respectively. and the rtio in the Doenjang aged for 60 days was 91 :9 , indicating that dialysate slowly days, respectively, and the ratio in the Doenjang aged for 60 days was 91 : 9, incidatin that dialysate slowly increased by the fermentation . Both portion exhibited strong antioxidant activity, but more stronger antioxidant activity was found in the dialysate. DEAE-celluose column chromatography showed that dialysate contained more materials eluted by 0.01-0.03M HCI solution than 0.01M acetate buffer, but diffusate showed opposite results. The degree of browning reaction and antioxdiant activity found in the fraction eluted by HCI solution was stronger than that of the fraction eluted by acetate buffer. The fraction eluted from DEAE-cellulose column chormatogrphy was further fractionaged by TLC and found that strong antioxidant activity was present in the fractions which did not possess fluorescenece and showed a negative ninhydrin reaction. TLC fractions of HCI eluant in Meju exhibited a strong absorbance at 260-280nm, but most of other fractions did not show any absorbance at UV region. TLC fractions from dialysate and diffusate showed fairly identical IR spectrum with absorbance at 3400cm-1, 2800cm-3000cm -1, 1600cm, -1 1400cm-1 and 1100 cm-1 , however, in addition to these absorbances, the spectrum from HCI eluant of Meju exhibited a strong absorbance at 1750cm , indicating the carbonic acid or carbonate ester.

• Preventive Nutrition and Food Science
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• 제22권1호
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• pp.37-44
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• 2017

Sulfur-containing amino acids play important roles in good flavor generation in Maillard reaction of non-enzymatic browning, so aqueous model systems of glucosamine and cysteine were studied to investigate the effects of reaction temperature, initial pH, reaction time, and concentration ratio of glucosamine and cysteine. Response surface methodology was applied to optimize the independent reaction parameters of cysteine and glucosamine in Maillard reaction. Box-Behnken factorial design was used with 30 runs of 16 factorial levels, 8 axial levels and 6 central levels. The degree of Maillard reaction was determined by reading absorption at 425 nm in a spectrophotometer and Hunter's L, a, and b values. ${\Delta}E$ was consequently set as the fifth response factor. In the statistical analyses, determination coefficients ($R^2$) for their absorbance, Hunter's L, a, b values, and ${\Delta}E$ were 0.94, 0.79, 0.73, 0.96, and 0.79, respectively, showing that the absorbance and Hunter's b value were good dependent variables for this model system. The optimum processing parameters were determined to yield glucosamine-cysteine Maillard reaction product with higher absorbance and higher colour change. The optimum estimated absorbance was achieved at the condition of initial pH 8.0, $111^{\circ}C$ reaction temperature, 2.47 h reaction time, and 1.30 concentration ratio. The optimum condition for colour change measured by Hunter's b value was 2.41 h reaction time, $114^{\circ}C$ reaction temperature, initial pH 8.3, and 1.26 concentration ratio. These results can provide the basic information for Maillard reaction of aqueous model system between glucosamine and cysteine.

• Asian-Australasian Journal of Animal Sciences
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• 제30권12호
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• pp.1711-1717
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• 2017

Objective: This experiment was studied the effects of various levels of crude glycerin (CG) in dairy goat diet on daily intake, milk yield, milk composition, some physical properties and some quality changes of goat milk after sterilization. Methods: Twelve 75% Saanen dairy goats (body weight = $49{\pm}3kg$; days in milk = $60{\pm}12d$) were randomly assigned in a completely randomized design to evaluate the effects of three experimental diets consisting of 0%, 5%, and 10% CG (dry matter basis) which were formulated to meet or exceed the nutrient requirements of goats. Experimental dairy goats were evaluated for feed and milk yield. Milk samples were analyzed for their composition, including fatty acids, casein profile, fat globule size, and color, and were sterilized to evaluate milk heat stability. Results: There were no significant differences between 0% and 5% CG treatments infeed. Increasing CG supplementation from 0% to 5% increased milk yield from $2.38{\pm}0.12$ to $2.64{\pm}0.23kg/goat/d$. In addition, milk samples from 5% CG treatment had the highest total solids, fat content and lactose content, and largest fat globule size. Increasing CG to 10% resulted in a decrease in milk fat. After sterilizing at $116^{\circ}C$, $F_0=3min$, goat milk samples from 5% CG treatment had slightly higher sediment content and comparatively higher degree of browning. Conclusion: Considering milk yield, milk fat content and quality of sterilized milk, 5% CG supplementation in a total mixed ration has a potential for implementation in dairy goats.

• 한국식품과학회지
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• 제25권3호
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• pp.204-209
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• 1993

용매의 종류와 추출온도, 시간, 용매첨가량, 추출횟수 등의 추출조건이 계피추출액의 이화학적 특성에 미치는 영향을 조사하였다. 수소공여능으로 나타낸 항산화활성도는 12가지 용매중 물과 70% 에탄올 추출액에서 높게 나타나 물과 70% 에탄올을 다음의 추출조건을 조사하기 위한 적정용매로 선정하였다. 추출온도를 $20{\sim}100^{\circ}C$로, 추출시간을 $2{\sim}10$시간으로 하여 추출액을 조제했을 때 항산화활성도와 총 phenol 함량은 $80^{\circ}C$와 8시간 추출액에서 높게 나타났고 285nm와 490nm에서의 흡광도는 온도가 높을수록 증가하였다. 용매 첨가비에 있어서는 계피중량의 20배 이상 첨가시에 큰 변화가 없었으며 추출횟수는 3회 이상의 추출액에서 항산화활성도 및 기타 특성이 현저히 감소하였다.

• 동아시아식생활학회지
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• 제7권3호
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• pp.309-314
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• 1997

밤꽃에 대한 기초자료를 얻기 위하여 밤꽃 중의 화학적인 특성을 조사하였으며, 그 결과는 다음과 같다. 밤꽃에 함유된 총당, 환원당, 조단백질, 조지방 및 회분의 함량은 개화전 시료에서 10.44, 4.91,. 8.80, 1.42 및 0.87%였으며, 개화 후 시료에서는 각각 11.75, 7.04, 7.71, 2.26 및 0.66%이었다. 밤꽃 물추출물의 갈변도는 개화전의 시료가 개화후의 시료보다 높았으며, flavonoids와 nonflavonoids의 함량은 개화전 시료에서 7.05와 0.52%였고, 개화 후에는 2.08과 0.22%이었다. Sucrose, fructose 및 glucose와 같은 유리당의 함량은 개화전 시료에서 2.90, 0.72 및 0.71%였으며, 개화 후에는 2.65, 2.10 및 2.20%였다. 개화전 밤꽃의 주요 아미노산은 threonine, proline 및 cystine이며, 그 함량은 각각 28. 96, 12.49 및 11.43%이었고, 개화후의 시료에서는 aspartic acid 및 glutamic acid로 그 함량이 각각 16.19와 11.9%이었다.