Search | Korea Science

Chuang, Ju-Tzu;Chen, Tsun Chieh;Jeong, In-Hak;Yi, Young-Hyoun
- Korean Journal of Food Science and Technology
- /
- v.23 no.6
- /
- pp.717-722
- /
- 1991
The effects of preparation methods, packaging, and additives on shelf life of appetizer chicken drummettes were investigated. Initial microbial loads of appetizer drummettes affected their refrigerated shelf life. Drummettes cooked to $93.3^{\circ}C$ had lower initial microbial loads and longer shelf life when compared to those cooked to $82.2^{\circ}C$. However, this advantage was not observed when 'rub' was applied during the marinating process. No apparent effect (P>0.05) on the growth of psychrotrophs was found when samples were stored at $3{\pm}1^{\circ}C\;and\;7{\pm}1^{\circ}C$ with or without vacuum packaging. Adding sorbic acid (0.5%) or sodium benzoate (0.5%) in the marinade mixture extended the refrigerated shelf life. The addition of 50 ppm sodium nitrite further enhanced the shelf life. The increased TBA values of drummettes can be reduced by the application of vacuum packaging. The addition of sorbic acid or sodium benzoate in the marinade was not as effective as vacuum packaging in retarding TBA value increase.
PDF

Hong, Seok-In;Kim, Yun-Ji;Park, Noh-Hyun
- Korean Journal of Food Science and Technology
- /
- v.25 no.3
- /
- pp.270-276
- /
- 1993
Leaf lettuce (Lactuca sativa L., var. crispa) packed in $20{\mu}m$ LDPE (perforated), $20{\mu}m$ LDPE, $30{\mu}m$ HDPE, and $40{\mu}m$ LDPE pouches was stored at $4^{\circ}C,\;10^{\circ}C\;and\;20^{\circ}C$. The quality of leaf lettuce during the storage was investigated in terms of weight loss, color, soluble solids content, texture and sensory properties. Leaf lettuce exhibited the highest storage stability at $4^{\circ}C$. Shelf-life of the packed leaf lettuce was prolonged approximately $10{\sim}15$ times in comparision with that of the unpacked under all temperature conditions. Among the packed leaf lettuce, self-life in $20{\mu}m$ LDPE (perforated) and $20{\mu}m$ LDPE pouches was relatively short mainly due to discoloration and deterioration. On the other hand, the quality of the leaf lettuce packed in $30{\mu}m$ HDPE and $40{\mu}m$ LDPE pouches was kept well during the storage. Particularly, $40{\mu}m$ LDPE pouches conferred the shelf-life superior to other film pouches.
PDF

Hwang, Seong-Jae;Kim, Seong-Min;Rhee, Suk-Keun
- International Journal of Highway Engineering
- /
- v.11 no.4
- /
- pp.95-105
- /
- 2009
This study was conducted to investigate the effects of concrete flexural strength and surface smoothness, which were pay factors of concrete pavements, on pavement performance, and to develop the methodologies to determine the proper allowable ranges according to the magnitudes of those pay factors. The concrete flexural strength was analyzed using the AASHTO, power, and linear fatigue failure models, and the surface smoothness was analyzed for the roughness indices of PSI, IRI, and PrI using the AASHTO model. The analysis results showed that the allowable range of the flexural strength should be determined using the rate between the deficiency and strength, and the penalty should be linearly proportional to the strength deficiency rate because the linear relationship between the strength deficiency rate and the reduction in pavement life was observed. As the initial surface smoothness became better, the smoothness deficiency rate should be larger. The penalty due to the surface smoothness deficiency should also be linearly proportional to the smoothness deficiency rate.
PDF

Yoo, Pyeong-Jun;Lee, Dong-Hyun
- International Journal of Highway Engineering
- /
- v.4 no.4 s.14
- /
- pp.1-12
- /
- 2002
Pavement Management System has a special purpose that the rehabilitation strategy applied on pavement should be executable in view of technical and economical point after new pavement open to the traffic. To achieve that purpose, a reliable pavement performance prediction model should be embeded in the system. The object of this study is to develop a probabilistic pavement performance prediction model for evaluating asphalt pavements based on the Markov chain concept. In this paper, methodology of the Markov chain modeling principle is explained, and the application of this model to asphalt pavement is described. As the results, transition matrics for predicting asphalt pavement performance are obtained, and also performance life is estimated quantitatively by this system.
PDF