• 농업과학연구
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• 제41권1호
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• pp.9-16
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• 2014

This experiment was conducted to examine the effects of a short-term treatment of high pressure $CO_2$ on shelf-life of strawberry fruit. A short-term treatment (12 hr) of 100% $CO_2$ resulted in the increase of fruit firmness up to 71.9% compared to that at harvest. The firmness of $CO_2$ treated fruit remained a significantly higher than that of control (air) up to 15 days. The alteration of pectic polymers was observed by $CO_2$ treatment such as an increase of EDTA soluble pectins and decrease of water soluble ones. The $CO_2$ treatment resulted in the increase of total amount of wall bound calcium. Pectate lyase activity, an important agent of strawberry fruit softening, was also significantly reduced by $CO_2$ treatment. Contents of soluble solids and acids of $CO_2$ treated fruit were higher than those of control fruit. Short-term treatment of high pressure $CO_2$ affected shelf-life through firmness increase whereas the visual quality and decay incidence of strawberry fruit were not affected.

• Preventive Nutrition and Food Science
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• 제15권2호
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• pp.152-158
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• 2010

This study was designed to determine the best cultivar of kohlrabi for making pickles among KM-1 (Worldcol), KM-2 (Bejo), KM-3 (Takii), and KM-4 (Monsanto) cultivars. The initial pH of pickles was different in all cultivars; however, they all had a pH in the range of 3.81~3.86 after 28 days of storage. The pickles made from KM-4 had the lowest acidity, while there was no significant difference in acidity among the KM-1, KM-2, and KM-3 pickles. The salinity of all kohlrabi pickles was consistent during the storage period. The changes of color values were accelerated in the following order: KM-4>KM-1>KM-2>KM-3. Though kohlrabi pickles were non-fermented, the change in reducing sugar contents was similar to that of a fermented pickle. The highest value of reducing sugar content was found in pickles made with KM-4. In all cases, the firmness of the pickle decreased as time of storage increased. On the initial day, KM-4 pickle showed the highest firmness with 807.4 g. KM-4 also showed the highest firmness on the 28th day of storage with 602.3 g. In sensory evaluation, the KM-4 pickle exhibited the highest texture (hardness) among the pickles. The pickle made with the KM-4 cultivar showed relatively higher firmness of texture than other cultivars, suggesting that KM-4 could be utilized in other kinds of processed foods, in addition to being pickled.

• Journal of Biosystems Engineering
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• 제30권2호
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• pp.127-133
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• 2005

Precision tillage is designed to till lands variably according to their firmness. Therefore, it is necessary to measure soil firmness in fields and present it in a form with which the variable tillage on be performed. Such forms may be classified into two categories: sensor-based and map-based forms. The map-based approach appears to be inevitable until the technology develops high enough to secure the sensor-based approaches. The first step for map-based precision tillage may be to develop a tillage recommendation map. In this study, a tractor-mountable automatic soil firmness measurement system was developed to construct a cone index map. The system is comprised of three ASAE Standard cone penetrometers and a hydraulic unit for controlling operation of the penetrometers. The system is designed to conduct stop-and-go measurements in fields. The measurements from the three penetrometers are transferred to a microcomputer and the average cone index was calculated. This average cone index was taken as soil firmness of the location where the measurement was made. The cone indices thus determined were used to construct a cone index map using the ArcView software. The system also displays the soil penetration resistance, cone index and soil depth as the cone penetrates into the soil. The field performance of the system was evaluated and the cone index maps at different depths were also presented.

• 농업과학연구
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• 제29권1호
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• pp.24-31
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• 2002

본 연구는 수출용 딸기에 대한 실용적 $CO_2$ 처리방안을 도입하여 수출단계에서 과실 품질에 미치는 영향을 조사하기 위하여 실시하였다. $CO_2$ 처리에 따른 경도 증진 효과는 과숙한 과실에서 더욱 컸으나 과실의 실제적인 경도는 미숙한 과실에서 높아 미숙과에 대한 처리 효과가 실용적인 가치가 있었다. 처리조건은 수확한 과실을 예냉실에 넣어 냉각시키고 15% 이상의 $CO_2$에 4시간 이상 노출시키는 것이 바람직 하였으며 $CO_2$ 처리의 잔류효과는 모의 선적 및 소매과정까지 유지되었다. 그러나 과숙한 과실에서는 소매과정을 부여할 때 과피면이 검붉게 변하여 상품가치를 상실하였다. 본 연구 결과에서 농가 소유의 소형 저온실을 활용하여 간편하게 $CO_2$를 처리할 수 있으므로 수출은 물론 국내 유통에서 품질 증진을 위한 수확 후 처리기술로 활용 가능성이 있었다.

• 원예과학기술지
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• 제29권4호
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• pp.298-305
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• 2011

본 연구는 칼슘제의 엽면살포를 이용하여 국내육성 스탠다드 국화 '백마' 의 줄기 경도를 증대함으로써 상품성 향상 및 수송시 줄기가 부러져 절화의 품질이 떨어지는 문제점을 방지하고자 수행하였다. '백마'의 칼슘제 선발시험은 염화칼슘($CaCl_2{\cdot}2H_2O$), 질산칼슘[$Ca(NO_3)_2{\cdot}4H_2O$], OS-Ca(굴껍질에서 추출한 천연 액상 칼슘 화합물)을 사용하였으며 Ca 함량을 기준으로 처리농도는 0, 0.001, 0.01, 0.1, 1.0%로 엽면살포하였다. 모든 칼슘제 1.0% 처리구에서 엽소 현상과 줄기가 휘어지는 심한 약해가 나타났다. OS-Ca는 또한 다른 칼슘제보다 '백마'에 흡수가 가장 잘 되었기 때문에 가장 심한 약해 현상이 나타난 것으로 보인다. 수확 후 최대 줄기경도는 다른 칼슘제 처리구보다 OS-Ca에서 더 높았으며, 특히 0.01% OS-Ca 처리구가 가장 우수하였다. 반면, 탄성강도와 최대굴곡강도에서는 0.001% OS-Ca 처리구가 다른 처리구보다 높게 나타났다. 따라서 OS-Ca 처리시 약해가 발생하지 않았던 농도인 0.005에서 0.05% 사이를 범위로 하여 '백마'의 줄기 강화에 적합한 칼슘제로 OS-Ca을 선정하였다. 다음 실험에서는 OS-Ca의 처리농도를 0, 0.005, 0.01, 0.05%로 세분화하여 처리하였다. OS-Ca 처리 후 생육을 조사한 결과, 0.05% OS-Ca에서 초장, 상 중부 줄기 직경, 엽수 및 부위별 건물중에서 무처리와 다른 처리농도보다 우수하였다. OS-Ca의 농도에 따른 줄기 경도에 있어서는 줄기 내 칼슘 함량, 최대경도, 탄성강도, 최대 굴곡강도에서 0.05% OS-Ca 처리구가 가장 우수하게 나타났고, 무처리구와 OS-Ca 처리구 사이에서 고도의 유의성을 나타내었다. 그러나 줄기횡단면의 총면적, 수조직 면적, 공동 면적, 공동률은 무처리구를 포함하여 모든 처리구 간의 유의성은 없었다. 따라서 '백마'의 줄기 경도와 줄기 공동률 간의 상관관계는 없는 것으로 판단되었다. 결론적으로, 백마의 영양생장기에 가장 적절한 엽면살포 칼슘제와 농도는 0.05% OS-Ca였으며, 수송시 백마의 줄기 경도를 강화시킬 것으로 판단되었다.

• Journal of Biosystems Engineering
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• 제30권1호
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• pp.38-44
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• 2005

In this study, the acoustic response technique was applied to evaluate the maturity of melon nondestructively. The acoustic response signals through melon were obtained by microphone and signal conditioner with the lapse of days after fruit set. The acoustic parameters such as resonant frequencies and the spectrum energy ratio were analyzed. To investigate the relation between acoustic parameters and firmness of melon, the compression test was performed. Three resonant frequencies representing f1, f2 and f3 were 150 to 250 Hz, 300 to 400 Hz, and 450 to 550 Hz, respectively. The resonant frequencies were shifted to the lower frequencies and the magnitude of spectrum decreased as the maturity of melon increased. Some significant correlations were found between melon firmness and the spectrum energy ratio in some frequency ranges. It is possible to estimate the maturity of melon by acoustic response technique.

• 한국축산식품학회지
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• 제38권5호
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• pp.901-911
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• 2018

Response surface methodology was used to study the effect of egg albumen (5-15 g), vegetable oil (5-15 g), and corn bran (5-15 g) on sensory and textural (firmness and toughness) quality of chicken nuggets cooked by the oven, steam, and microwave methods. The egg albumen and vegetable oil had a positive linear effect but corn bran had a negative linear effect at p<0.01 on sensory overall acceptability scores of nuggets. Firmness and toughness scores were increased significantly (p<0.01) with the increase in corn bran level in the formulation. The optimum level of egg albumen, vegetable oil, and corn bran were obtained and validated. Cooking methods also affected the sensory and textural quality of nuggets. Steam cooked nuggets had higher values of sensory scores than oven and microwave cooked nuggets. Oven cooked nuggets showed higher values of firmness and toughness than steam and microwave cooked nuggets. Results of this study suggest that emulsion based meat products can be enriched with dietary fiber source like corn bran without compromising the sensory and textural quality of the products.

• 한국토양비료학회지
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• 제50권4호
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• pp.215-225
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• 2017

Kiwifruit is prone to damage by frost in the harvest season and the occurrence of postharvest diseases. Accordingly, new cultivars overcoming these disadvantages have been developed. Compared to existing cultivars, studies on diseases in new cultivars are very limited. Thus, goal of this study was investigation of fungal infection occurrences in new cultivars. Kiwifruit was harvested in 2014 and 2015 year, respectively. In both years, cvs. Goldone and Redvita showed more resistance against fungal infection but cv. Gamrok was more sensitive compared with cv. Hayward. Major fungi were identified as Botryosphaeria dothidea, Phomopsis sp., Alternaria alternata and Nigrospora sp. Firmness and soluble solids content were also influenced by the occurrences. This study's findings are important for providing practical information on new cultivars in the kiwifruit industry.

• Journal of Biosystems Engineering
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• 제28권3호
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• pp.239-244
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• 2003

The potential use of ultrasonic technique for firmness measurement of apples was evaluated. Mechanical properties(bioyield deformation, bioyield strength, rupture deformation, ultimate strength, and elastic modulus) and ultrasonic parameters (ultrasonic velocity, attenuation coefficient and the first peak frequency) of the apple flesh during the storage time were measured and analyzed. Ultrasonic parameters were determined from the measurement of ultrasonic wave transmission through the apple flesh specimen. Mechanical properties were obtained by universal testing machine. The bioyield strength, rupture strength, elastic modulus, ultrasonic velocity, and the first peak frequency of the apple flesh decreased with the storage time. The bioyield deformation, rupture deformation, and ultrasonic attenuation coefficient increased with the storage time. The correlation analysis between ultrasonic parameters and mechanical properties and the storage time was performed. The high correlations were found between the storage time and the ultrasonic parameters, and these relationships seem to be useful for determining the firmness of the apple flesh.

• Asian-Australasian Journal of Animal Sciences
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• 제14권10호
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• pp.1470-1476
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• 2001

Kou Woan Lao is an oriental-style dairy product, which is coagulated by milk-clotting enzyme from the culture filtrate of lao-chao. The product appears smooth, sweet, slightly wine flavour, and the flavour differs from yogurt. The aim of this study was to search for the optimum model to shorten the period of manufacture, and to improve the quality of Kou Woan Lao. A response surface design was used for studying the effects of addition of carrageenan, locust bean gum, and culture filtrate from lao-chao on the curd firmness, viscosity, and syneresis. Results indicated that the best rheological property, preservative quality and acceptability of Kou Woan Lao could be obtained by the combination of 0.22% carrageenan, 0.21 % locust bean gum and 12% culture filtrate from lao-chao. The curd firmness, viscosity and syneresis of resultant product were 29.3 g, 21,347.7 cps, and 8.92%, respectively and the microstructure of the curd revealed a relatively complete three-dimensional spider web-like structure.