• 한국식품과학회지
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• 제46권5호
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• pp.636-640
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• 2014

도라지 건조방법에 대한 기본 정보를 제공하고자 일광건조, 열풍건조 그리고 동결건조를 실시하여 무기성분과 환원당 그리고 사포닌 함량을 조사한 결과를 요약하면 아래와 같다. 칼륨과 칼슘은 각각 22.6과 9.2 mg%로 열풍건조에서 높게 나타났다. Platycodin D는 열풍건조에서 622.0mg%로 가장 높게 나타났으며, platycodin D3, Polygalacin D, deapioplatycodin D는 일광건조에서 각각 113.5, 756.6, 109.2 mg%로 나타났다. Glucose와 platycodin D, platycodin D3, deapioplatycodin D의 함량간의 상관계수는 각각 -0.924, -0.957, -0.861로 고도의 음의 상관을 보였다(p<0.01). 동결건조가 다른 건조조건에 비해 색이 밝게 나타났다. 이상의 결과로 도라지의 건조 방법은 일광건조와 열풍건조가 동결건조보다 좋은 것으로 평가 되었지만 일광건조는 건조기간이 길어 많은 노동력이 소요된다. 따라서 열을 가하여 건조하면서 건조기간도 줄이고 도라지 약리성도 높이기 위한 적정 건조 온도에 관한 연구도 수행 되어야 할 것으로 사료된다.

• Current Research on Agriculture and Life Sciences
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• 제32권2호
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• pp.67-73
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• 2014

Mulberry fruits were semi-dried using hot air ($60-100^{\circ}C$) or cool air ($20-40^{\circ}C$), and the effects of the drying temperature and processing time on the quality of the final dried mulberry fruits were investigated. Response surface methodology was employed to establish a statistical model and predict the conditions resulting in minimal loss of the total phenolic content (TPC) and ascorbic acid. Thus, using overlapped contour plots, the optimal conditions for producing semi-dried mulberry fruits, which reduced the moisture residue to 45% and minimized the nutrient losses of TPC and ascorbic acid, were determined for the hot-air process ($60.7^{\circ}C$ for 5.4 h) and cool-air process ($34.8^{\circ}C$ for 23.3 h). Plus, a higher drying temperature was found to lead to a faster loss of moisture and ascorbic acid, while the TPC was significantly decreased in the cool-air dried mulberry fruits due to the higher activity of polyphenol oxidase between 30 and $40^{\circ}C$.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.1191-1196
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• 2006

Analysis of drying characteristics has been carried out with one-dimensional model in the dryer using the principle of the refraction of radiation. The dryer is composed of hot water tank, a plastic film conveyer belt, drying material, etc. The model considers the conduction and radiation within the plastic film and drying material. The film is semitransparent to radiation and the drying material is assumed to be semitransparent or opaque to radiation. The results shows that the effect of radiative transfer on the drying rate is relatively large when the thickness of drying material is small and the water temperature is high. When the material is thin, the drying rate by only conduction is also enhanced so that drying time can considerably be reduced.

• 한국식품저장유통학회지
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• 제2권1호
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• pp.155-161
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• 1995

We examined the drying characteristics and the drying rate model equation of garlic(allium sativum L.) using computer aided convective drying. The drying chanacteristic curve of garlic divided into constant rate drying period and 2 stage of falling rate drying period. The drying rate was fairly affected by hot air temperatures during the total drying period, but air flow rates has nearly no effect on the drying rate except initial drying period. Of the several model equation, r2 values of page model equation was the highest, and the estimated drying profiles were comparatively coincided with the observed drying profiles. Page model equation was suitable to predict the drying rate and moisture content during drying of sliced garlic.

• Journal of Biosystems Engineering
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• 제25권3호
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• pp.227-232
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• 2000

A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) of moisture contents to 16.7%(w.b), by prototype dryer and the average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to a conventional natural air dryer in which grains were not mixed during drying periods. The dryer performance evaluation index was 738.3kJ/(kg.water), which was more effective than that of grain circulation type hot air dryer(3,500∼5,000 kJ/kg.water)

• 한국약용작물학회지
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• 제19권5호
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• pp.354-361
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• 2011

In order to product dry goods of Gastrodiae Rhizoma with high quality, tubers were treated with various dry methods such as cutting, drying methods and steaming. In cutting than no cutting, they were shown shorter drying hours and lower drying yield. Drying hours in freeze drying was shorter than those of hot air and far-infrared ray. Total polyphenol content was higher in cutting than no cutting. According to steaming, it was increased in freeze drying but decreased rapidly in the other dry methods. Among all treatments, hot air dry treatment with cutting and no steaming had the highest total polyphenol content. Gastrodin and 4-hydroxybenzyl alcohol contents generally were similar or higher in cutting than no cutting. By steaming, gastrodin content in freeze drying was decreased but 4-hydroxybenzyl alcohol content was increased. But hot-air and infrared ray dry, they were shown opposite results. Gastrodin and 4-hydroxybenzyl alcohol contents showed opposite reaction to each other and were shown various response by dry methods.

• 한국식품과학회지
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• 제19권1호
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• pp.5-11
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• 1987

수산식품의 품질보존에서 문제시되고 있는 지질의 산화생성들이 단백질의 영양학적 변화에 미치는 영향을 검토하기 위하여 새우를 시료로하여 건조과정과 저장중에 생성되는 지질의 산화생성물과 유효성 lysine간의 반응과 갈변반응에 미치는 영향을 실험한 결과는다음과 같다. 새우를 5%식염수에서 자숙한 후 $30{\pm}5^{\circ}C$에서 30시간 열풍건조 및 천일건조하였을 때 과산화물값은 열풍건조한 시료에서 12시간후, 천일건조한 시료에서는 18시간후에 증가하여 저장 15일경에 최고도에 달하였다. TBA값은 건조과정중에 급격히 증가하였으며 저장 25일경부터는 서서히 감소하였다. 유효성 lysine은 건조과정중 지질이 산화됨에 따라 감소되었으며, 특히 감소현상은 건조초기에 현저하였다. 지질이 산화됨에 따라 갈변색소는 증가하는 경향을 나타내었으나, 큰 차이는 없었다. 이상의 결과로부터 새우는 건조과정에서 지질이 산화됨에 따라 유효성 lysine의 량이 감소됨을 알 수 있었으나 건조방법에 의하여서는 큰 차이가 없었다.

• 한국식품저장유통학회지
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• 제23권5호
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• pp.689-695
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• 2016

약용버섯(영지버섯, 상황버섯)과 식용버섯(새송이버섯, 표고버섯)을 장방형(1 cm)과 정방형($1{\times}1cm$)으로 절단하여 자연건조와 열풍건조($50^{\circ}C$, $70^{\circ}C$)하면서 건조특성을 조사하고 건조 시료의 수축률, 색도 및 재수화성을 조사하였다. 건조 전의 초기수분함량은 약용버섯에 비해 식용버섯이 높았으며, 건조 후 최종수분함량은 약용버섯이 높았다. 건조속도는 $70^{\circ}C$ 열풍건조가 가장 빨랐으며, 장방형절편보다 정방형절편에서 건조 속도가 빨랐다(p<0.05). 수축률은 약용버섯은 $50^{\circ}C$ 열풍건조, 식용버섯은 $70^{\circ}C$ 열풍건조가 가장 작았으며 정방형 절편이 장방형에 비해 낮았다(p<0.05). Hunter 색차계로 색도 값을 조사한 결과, 약용버섯은 자연건조구, 식용버섯은 열풍건조구가 색도 변화가 작았으며, 갈변도를 나타내는 ΔE값도 적었다(p<0.05). 재수화율은 약용버섯은 $50^{\circ}C$ 열풍건조구, 식용버섯은 자연건조구에서 높게 나타났다(p<0.05). $50^{\circ}C$ 열풍건조가 비교적 건조시간이 짧으며, 수축률이 낮고, 갈변이 적게 일어나며, 재수화율이 높아서 효율적인 것으로 사료된다.

• 한국조리학회지
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• 제20권1호
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• pp.55-64
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• 2014

블루베리를 열풍건조, 순환형 감압건조 및 동결건조의 방법으로 건조제품을 제조하여 품질특성과 생리활성을 비교조사 하였다. 일반성분 중 가장 많이 함유하고 있는 성분은 건조방법과 무관하게 탄수화물(68.48~80.00%)이었으며, 다음으로 수분(13.10~27.93%), 조단백질(1.63~5.41%), 조지방(0.58~1.25%) 및 회분(0.71~1.11%) 순으로 나타났다. pH는 순환형 감압건조시료의 pH가 유의적 차이가 없었으며, 갈변도의 경우 0.31~0.21의 값으로 건조 방법별로 차이가 많았다. 색도는 L값과 a값은 동결 건조한 시료가 더 높게 나타난 반면, b값의 경우 열풍, 순환형, 동결건조시료 순으로 높은 값을 나타내었다. 열풍 건조한 시료의 비타민 C 함량은 5.6 mg/100g이었으며, 순환형 감압건조 및 동결건조 시료의 비타민 C 함량은 6.9 mg/100g, 7.1 mg/100g으로 나타났다. 안토시아닌 함량은 10.08 mg/100g, 29.41 mg/100g, 33.87 mg/100g의 함량을 나타내어 안토시아닌 함량 역시 동결건조시료에서 더 높은 수치를 나타내었다. 열풍건조시료의 유리당 함량이 695.5 mg/100g으로 가장 높게 나타났다. 페놀함량과 DPPH 라디칼 소거능은 순환형 감압 건조 및 동결 건조가 높게 나타났다.

• 한국식품영양학회지
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• 제36권4호
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• pp.327-333
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• 2023

This study investigated the antioxidant characteristics of sweet potato according to different plant parts and drying methods. The sweet potato plant parts were divided into root tubers, stems, stalks, leaves, and tips, and the drying methods were freeze-drying and hot air drying. Total polyphenol and flavonoid contents and radical scavenging activity of the sweet potato plant parts were significantly different depending on the plant parts and drying methods. The total polyphenol content of freeze-dried sweet potato leaves and tips were 52.76 and 46.19 mg chlorogenic acid equivalents/g sample, and the total flavonoid contents were 222.47 and 214.12 mg quercetin equivalents/g sample, respectively, and decreased with hot air drying. DPPH radical scavenging activity was higher in freeze-drying than hot air drying and was significantly different depending on the plant parts. The ABTS radical scavenging activity of freeze-dried sweet potato leaves and tips were 43.48 and 44.68 mg Trolox equivalents/g sample, respectively, and decreased with hot air drying. Therefore, additional studies on the functionality of using by-products from sweet potato cultivation are needed.