• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.125-131
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• 2010

Quality improvements of Naengmyeon broth were explored by adding prickly castor-oil tree extract to the broth. Samples of Naengmyeon broth containing various levels (0, 0.1, 0.2, 0.3, 0.4%) of prickly castor-oil tree extract were stored at $4^{\circ}C$ for five days. During storage, the pH decreased with an increase of total acidity; however, this decrease in pH was slowed with by increasing levels of prickly castor-oil tree extract. Turbidity levels, along with total solid contents in the liquid portion of the Naengmyeon broth, increased in all treatments as storage proceeded, although the extent was somewhat suppressed by the prickly castor-oil tree extract. As a result of storage, colorimetric lightness values decreased and redness and yellowness increased. Total viable cells and coliform bacteria were lower in the Naengmyeon broth with added prickly castor-oil tree extract compared to the control. Also, with increasing prickly castor-oil tree extract concentration, fewer total viable cells and coliform bacteria were observed. The VBN contents of the broth samples containing prickly castor-oil tree extract was higher than of control, and the more prickly castor-oil tree extract were higher than the VBN content of the control; moreover, as prickly castor-oil tree extract content increased, less VBN was detected. In sensory evaluations, the 0.3% treatment was the most favored in terms of color, smell, sour taste, carbonated taste, and the overall acceptability. In conclusion, the addition of prickly castor-oil tree extract, having antimicrobial activity and natural antiseptic qualities, improved the storage duration of Naengmyeon broth. Also, the sensory characteristics of the 03% treatment were especially preferred.