• Journal of Biosystems Engineering
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• v.13 no.2
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• pp.51-62
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• 1988

Bulk-type dryers which are widely used for drying special agricultural products such as tobaco leaf, red pepper, mushroom, ginseng, medicinal herb, etc, began to be distributed on a full scale since 1980 and the total number of dryers introduced to farms reached to about 36,600 units as of the end of 1986. In this study a survery was carried on the farmers cultivating special crops, dryer manufacturers and related administrative institutes and associations by means of on-the-spot investigation, mail or interview to collect data on scales and patterns of farming, utilization of bulk-type dryers, production and price streams of the special crops etc. Based on the analysis of the data surveyed predictions were made for the total demand on the bulk-type dryers and for annual demand over five-year span.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.362-368
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• 2002

가. 인공광원은 색온도, 연색지수, 파장대, 조도등에서 태양에 가장 근접한 메탈할라이드 등을 선정했다. 나. 광원을 공시비닐하우스에 적용키 위해 반사갓 재료 및 각도, 등 간격별로 요인시험한 결과 엠보싱처리 알루미늄 재료, 반사갓 각도 전후좌우 30$^{\circ}$, 등간격 550mm에서 가장 좋은 것으로 나타나 비닐하우스용 고추건조장치의 장조사부 설계.제작에 적용하였다. 다. 건조성능시험결과 시험구(인공광+열풍)가 대비구(열풍)에 비해 건감속도가 10.3-19.7% 향상되었고, 건조에너지도 16.1~17.1% 절감되는 것으로 나타났다. 라. 시험구 및 대비구의 색택(ASTA color) 및 당도에 대해 F-test 검증결과 5% 유의수준에서 고도의 유의차가 있는 것으로 나타났으며 ASTA color값은 차이가 컸으나 당도에서는 차이가 없는 것으로 나타났다. 결론적으로, 농가에서 사용하고 있는 하우스 열풍건조에 비해 색택 및 성분면에서 양호하기 때문에 비닐하우스 건조방식을 채택하는 농가를 대상으로 인공광조사 건조방식을 추가한다면 전천후 건조방식으로 적용이 가능할 것으로 사료되었다.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.819-826
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• 2014

This study was carried out to investigate the effects of night-time far-infrared irradiance quality of red pepper dried in greenhouses. This study involved 4 treatments: sunlight alone (control), or sunlight plus nightly far-infrared irradiation at $250W{\cdot}6.6m^{-2}$ ($250W{\cdot}6.6m^{-2}$), far-infrared irradiation at $250W{\cdot}3.3m^{-2}$ ($250W{\cdot}3.3m^{-2}$), or far-infrared irradiation $500W{\cdot}3.3m^{-2}$ ($500W{\cdot}3.3m^{-2}$). The drying periods were 12 days in $500W{\cdot}3.3m^{-2}$ and $250W{\cdot}3.3m^{-2}$, and 14 days in $250W{\cdot}6.6m^{-2}$, and 15 days in the control. The daytime temperature was same among the treatments. The lowest temperature was at $23.8^{\circ}C$ in control, and $29.5-37.2^{\circ}C$ in far-infrared irradiation treatments. The marketable yield was 7-14% higher in far-infrared irradiation treatments compared to the control. The rate of marketability was higher in far-infrared irradiation treatments (93.6-96.3%) than in the control (87.0-87.5%). The American Spice Trade Association (ASTA) value was greatest in the $250W{\cdot}3.3m^{-2}$ treatment, followed by $250W{\cdot}6.6m^{-2}$, then $500W{\cdot}3.3m^{-2}$, and finally the control. Capsaicinoid content showed no regular trend among the treatments. Our results provide an optimized method for reducing drying time of red pepper under sunlight, and improving the quality of dried red pepper.

• Food Science and Preservation
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• v.16 no.3
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• pp.362-370
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• 2009

Quality changes in semi-dried red pepper (SRP) treated with ozone water were observed upon storage (at $-18^{\circ}C$) after freezing at $-10^{\circ}C$, $-20^{\circ}C$, and $-40^{\circ}C$. Drip loss after treatment was greater than in control peppers, but no significant difference was evident between treatments (p<0.05). We observed that differences between samples decreased as storage time increased. Texture after treatment did not change significantly over a 3-month period. The redness (a-value) after treatment was greater than in the control, but no sample showed significant color alteration after the 3-month period. The capsaicinoid content decreasedas storage time increased, and was also affected by the freezing temperature. However, carotenoid content was not influenced by freezing or storage temperature. Ascorbic acid and free sugar contents showed decreases of 47% and 6.5%, respectively, after semi-drying. The results of sensory evaluation indicated no significant difference between samples in terms of color appearance.

• Food Science and Preservation
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• v.17 no.1
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• pp.1-8
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• 2010

We investigated the effect of freezing on changes in the chemical components of semi-dried red pepper (SDRP). We used storage temperatures of $0^{\circ}C,\;-10^{\circ}C,\;-20^{\circ}C,\;and\;-70^{\circ}C$. After 30 days of storage, capsaicin content had decreased by 40% at $0^{\circ}C$ and by 21% at $-20^{\circ}C$. Initial vitamin C content was 1,358.02 mg%. Compared with control, the $0^{\circ}C$ storage group showed a significant decrease in vitamin C content but no such decrease was noted in the $-20^{\circ}C$ and $-70^{\circ}C$ storage groups after 30 days. ASTA values were not influenced by storage temperature or period, in agreement with previous results. We concluded that storage was effective at temperatures of less than $-20^{\circ}C$. Next, both dried red pepper (DRP) and SDRP were stored at $-20^{\circ}C$ for 12 months. DRP had the lower level of capsaicinoids (55.01 mg%) owing to the long drying time. After 12 months, SDRP capsaicinoid had decreased by 30-33%, compared with a decrease of 54% in DRP. Initial vitamin C contents were 721.48 and 955.25 mg% in DRP and SDRP, respectively, and, after 12 months, vitamin C loss in the SDRP group (37%) was less than that in fresh red pepper (FRP) samples (45%). Initial $\beta$-carotene content was greatest in the FRP group (259.82 mg%), and that of DRP decreased by 20% after 12 months. The color a/b value of SDRP (1.40) was greater than that of DRP (1.00).

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.479-484
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• 1986

Two different types of solar collector for farm dryer- the flatplate type and the modified tubular type-were constructed and analyzed on their performances. The transparent plastic film, black painted galvanized iron sheet and black vinyl film were used for the cover and absorber of the flat-plate types. The simplified tubular type was constructed with transparent films for the cover and black vinyl films for the absorber Two elliptical iron rings were used to form a tubular shape through which air could pass. No remarkable differences were found in thermal efficiences between the absorbers made with galvanized iron sheet and black vinyl film. The average thermal efficiencies of the solar collectors were 42.8%(max.48.2%, min.38.2%) for flat plate type and 22.971 (max. 25.4%, min. 14.8%)) for tubular one. The empirical equations were proved to be applicable to the prediction of temperature elevation. The tubular solar heat collector was successfully applied to red peppers drying as a practical farm dryer. The drying rate was almost doubled compared to a conventional sun drying.

• Journal of Biosystems Engineering
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• v.39 no.2
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• pp.96-100
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• 2014

Purpose: The objective of this study was to develop a classification index and the grade levels for a five-grade energy efficiency classification of agricultural dryers in Korea. Methods: The classification index and the grade levels were determined by using the performance test data published by the FACT over the last eight years to reflect a state of the art technology for agricultural dryers in Korea. The five grades were designed to have the classified dryers distributed normally over the grades with 15% for the $1^{st}$ grade, 20% for the $2^{nd}$ grade, 30% for the $3^{rd}$ grade, 20% for the $4^{th}$ grade and 15% for the $5^{th}$ grade. Results: The classification index was defined as the total amount of fuel and electrical energy consumed per 1% of the wet basis moisture content evaporated from a unit mass of grain or agricultural crops during the drying process: 1 MT of paddy rice for grain dryers and 1 kg of red pepper for agricultural crop dryers as the standard mass. Conclusions: The grade levels for the five-grade energy efficiency classification of grain dryers, kerosene dryers, and electric dryers were proposed in terms of the classification index value.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.97-104
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• 2012

The aim of this study was to investigate the quality properties of beef jerky replaced salt (NaCl) with red pepper paste, soy sauce and soybean paste. The quality properties of beef jerky including water activity ($a_w$), pH, moisture content, protein content, color, shear force, texture profile analysis and sensory evaluations were investigated. The sliced beef samples were marinated at salt (control), soybean paste (T1), soy sauce (T2) and red pepper paste (T3) for 24 h and then dried at $70^{\circ}C$ for 8 h. The $a_w$ and moisture content varied from 0.88 to 0.79 and from 28.87% to 22.98%, respectively. All treatment samples showed higher final $a_w$ and moisture content than the control sample after drying for the 8 h (p<0.05). The protein content of T2 and T3 samples were lower than the control. Also, shear force and hardness value of all treatment samples had lower than the control (p<0.05). However, all treatment samples showed lower saltiness intensity than the control sample. Sensory panelists recorded greater flavor and texture scores to the samples with soy sauce replacement. Therefore, sensory panels found that the T2 samples had better overall acceptability scores than the other beef jerky samples (p<0.05).

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.675-680
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• 1990

A near-infrared reflectance spectroscopic(NIRS) method which has been recently developed for a non-destructive method for measuring ingredients in foods and agricultural products especially was evaluated for the determination of capsanthin, total sugar, capsaicin and moisture contents in Korean domestic red peppers. A multiple linear regression analysis with the data obtained by standard-laboratory methods(capsaicin by GC, capsanthin by Colorimetry, total sugar by HPLC and moisture by Vacuum drying method) and NIRS method was carried out to make a calibration. The accuracy of the NIRS method was found to be adequate when the standard-laboratory values for a set of sample that were not included in the calibration, were compared. It is concluded that the NIRS method is suitable for the determination of total sugar and capsanthin.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.156-161
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• 1982

Three plastic film solar dryers covered with different film layer were constructed by modifying farm vinyl house and studied their performance. The collection efficiency and temperature raising of type C which was covered with double layers of transparent PE and black PVC film was most efficient, followed after B covered with double layer of transparent PE film and type A covered with single layer transparent PE film. The inside temperature of type C was average $18^{\circ}C$ higher than ambient temperature and its collection efficiency showed 31.5% with air flow rate of $3.8m^3/min$. The solar energy collection efficiency of type C was increased in proportion to air flow rate up to 60.2% at $11.3m^3/min$. In demonstration drying test of red pepper in type C, drying capacity per unit area was 2.5 times higher than that of conventional solar drying on straw mat and drying time shortened to about half.