This study was carried out to investigate shelf-life and quality of fresh-cut Dungkunma (Dioscorea bulbifera) in order to elevate utilization of Dungkunma a fresh food. Before vacuum-packaging (in polyethylene/polypropylene film (100μm, 15×20 cm, 75±2 cmHg) and storaging at 2℃, Dungkunma was peeled out and cut to dice type (2.0±0.5 cm3), and then washed and blanched using hot water (at 90±2℃ with 2% NaCl solution for 30 sec). Blanched Dungkunma was pre-dried at room temperature, 40℃ and 50℃ for removing surface water. Each peeled dice Dungkunma was packed 50 g in polyethylene/polypropylene film (100 μm, 15×20 cm) with vacuum treatment (75±2 cmHg) and stored at 2℃ for 90 days. Hardness and adhesiveness of Dungkunma blanched by 2% NaCl and pre-dried at 50℃ (SB50) were the highest, but changes were the least during storage. Lightness and yellowness of stored Dungkunma in all treatments decreased slightly while redness increased during storage. Changes of color of SB50 was the least. Total concentration of aerobic bacteria in SB50 was 1.88±0.18 log CFU/g during 90 days and E. coli was detected in all treatments during whole storage periods. Dioscin and allantoin contents of SB50 were virtually unchanged during the storage. Consequently, the results of this study suggest that vacuum packaged Dungkunma after blanching using 2% NaCl solution could be effective to prolong the quality of fresh-cut Dungkunma.

Background : Dungkunma (Dioscorea bulbifera, commonly known as the air potato, air yam, bitter yam, cheeky yam, potato yam) is a species of true yam in the yam family, and has been used as folk remedy to treat conjunctivitis, diarrhea and dysentery, etc. This study was carried out to investigate shelf-life and quality of fresh-cut Dungkunma (Dioscorea bulbifera) in order to elevate utilization of Dungkunma as fresh food. Methods and Results : Before vacuum-packaging (in polyethylene/polypropylene film (100 ㎛, 15 × 20 ㎝, 75 ± 2 ㎝Hg) and storage at 2℃, Dungkunma were peeled out and cut to dice type (2.0 ± 0.5 ㎤), and then washed and blanched (30 sec at 90 ± 2℃ hot water and 2% NaCl solution) and pre-dried at room temperature, 40℃ and 50℃ for removing surface water. Each peeled dice Dungkunma were packed 50 g in polyethylene/polypropylene film (100 ㎛, 15 × 20 ㎝) with vacuum treatment (75 ± 2 ㎝Hg) and stored at 2℃ for 90 days. Hardness and adhesiveness of Dungkunma blanched by 2% NaCl and pre-dried at 50℃ (SB50) was the highest and increased and decreased, respectively, but changes was the least during storage. Lightness and yellowness of stored Dungkunma in all treatments decreased slightly and redness increased during storage but changes of color was the least at SB50. On vacuum packing, SB50 showed 1.88 log CFU/g of total aerobic bacteria during 90 days, and E. coliwas detected in all treatments during whole storage periods. Dioscin and allantoin content of SB50 was virtually unchanged during the storage. Conclusion : Consequently, the results of this study suggest that vacuum packaged Dungkunma after blanching at 2% NaCl could be effective to prolong the quality of fresh-cut Dungkunma and could be easily used.

This study was conducted to investigate the effects of pretreatment and different packaging methods on the physicochemical properties of cold vacuum-dried peaches. All the dried peach samples were stored such as N2 gas substitution, vacuum and passive packaged with polyethylene (PE) film and oriented polypropylene (OPP)/aluminum (Al)/PE film at 40℃ for 50 days. The weight change, pH, soluble solids content, titratable acidity, soluble solid-acid ratio (SS/TA), delta E, browning degree and phenolic compounds were analyzed. The weight change and pH were lower in the 0.1% vitamin C-treated group and were significantly lowest in the vacuum-treated OPP/AL/PE. The soluble solids content and the SS/TA were higher in the non-treated groups than in the vitamin C-treated groups. According to the packaging methods, the L* values were higher in the vacuum, N2 gas and passive package, in that order. In addition, the browning degree and the delta E value were lower in the pretreated groups and significantly lowest in the vacuum-treated OPP/AL/PE with 0.1% vitamin C group. The phenolic compounds were high for the pretreated groups, according to the packaging methods (vacuum > N2 gas> passive), and the OPP/AL/PE was significantly higher than the PE. These results suggest that different packaging materials and pretreatment methods affected the quality of the dried peaches, and the vacuum- OPP/AL/PE film packaging group showed a high quality.

큰느타리 버섯의 polyethylene film(PE) 포장 저장성에 미치는 감압예냉(VP) 효과를 조사하였다. VP는 에서 품온이 가 될 때까지 40분간 행하였으며, 1 kg씩 PE포장하여 에서 30일간 저장하였다. 저장 중 중량감소율은 예냉처리구에서 다소 낮았다. 저장 4일째까지의 예냉구 포장내 농도는 2.44-14.50 % /kg-package/hr로 대조구의 2.01-8.19 %/kg-package/hr보다 현저하게 높았으며 저장 4일째

수도수(TW)와 0.5% sodium metabisulfite(0.5% SMS)를 대조구로 하고 강산성 전기분해수(SAEW: strong acidic electrolyzed water, pH 2.58, ORP 1,128 mV, HClO 105.0 ppm)와 약알칼리 전기분해수(LAEW: law alkaline electrolyzed water, pH 8.56, ORP 660 mV, HClO 73.8 mV)를 연근의 박피 후 침지액으로 하여 랩포장