• 한국식품영양과학회지
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• 제27권1호
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• pp.87-92
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• 1998

Major characteristics of shrinking and rehydration of Korean tea-leaves were investigated in the hot-air drying equipment. Experiments were performed with various drying temperature, plucking time, heating method and rolling condition. The values of shrinking raito and rate were the highest at 7$0^{\circ}C$ in the range of 3$0^{\circ}C$ to 9$0^{\circ}C$. The 1st tea-leaves and showed higher values. Shrinking ratio was 16.62 and 19.62% for leaves and stems; shrinking rate was found 0.083 and 0.091cm/hr.cm, respectively. The rehydration characteristics of tea-leaves at the drying temperature of 3$0^{\circ}C$ were fairly satisfactory. The 2nd tea-leaves showed higher value than others, while the natural tea-leaves were lower. Average rehydration ratio and rehydration rate constant were 85.7% and 0.063/min for leaves; 80.1% and 0.032/min for stems, respectively.

• 한국식품영양과학회지
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• 제19권3호
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• pp.195-200
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• 1990

Effects of cooking time(5-30 min in a pressure cooker) and HTST air dehydratiion time(0-9min at 15$0^{\circ}C$) on physical properties of dried green peas(3% oisture content wet basis) were investigated by determining rehydration ratio rehydration curve browning reaction and puncture force, The rehydration ratio and curve of dried green peas were increased with increa-sing cooking time and HTST air dehydration time. Preheating of the green peas for 30 min in a pressure cooker or for 9 min of HTST air dehydration time prior to 6$0^{\circ}C$ air dehydration recovered a 87.3% of original moisture content of raw green peas in a boiling water for 5 min. The brownin greaction was gradually decreased up to 15 min of cooking time. Puncture pressure of rehydrated green peas treated in a boiling water for 5 min was decreased as the cooking time and HTST air dehydration time were increased and was highly correlated with rehydration (r=-0.956) The effects of cooking time and HTST air dehydration time on rehydration ratio browning reaction and puncture pressure were significantly different at the a=0.01 level except effect of HTST air dehydration time on browning reaction.

• Preventive Nutrition and Food Science
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• 제14권4호
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• pp.367-372
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• 2009

Apple, persimmon, and strawberry slices were dehydrated after treating with 30, 50, and 80% (w/w) maltodextrin solution. The dried apple, persimmon, and strawberry slices were compared with hot air-dried and freeze-dried samples in terms of rehydration ratio, ascorbic acid, color, and sensory evaluation. The rehydration ratio of maltodextrin-treated samples was greater than that of hot-air or freeze-dried samples. Maltodextrin-treated samples had higher content of ascorbic acid than other dried samples. Additionally, maltodextrin-treated apple, persimmon, and strawberry slices had better color and sensory evaluations than those of freeze-dried or hot-air dried samples. These results suggest that, compared to other drying methods, dehydration of apple, persimmon, and strawberry slices using maltodextrin is very efficient, resulting in good rehydration capacity, minimal destruction of ascorbic acid, and good color and sensory evaluation.

• 한국축산식품학회지
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• 제41권1호
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• pp.153-163
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• 2021

This study was conducted to examine the effects of starch noodles (dangmyeon; SNs) with different starch sources and porcine intestines (PIs) with different pH on the rehydration stability of Korean blood sausage (sundae). Mungbean SN3 and PI3 (pH 9.18) showed significantly higher values of 80.69%-91.67% and 79.66%-80.98%, respectively, regardless of the drying methods (hot air, vacuum and freeze drying) (p<0.05). A number of larger pores were observed only in the cross-section of the freeze dried SN and PI through SEM. SN2 (potato starch) and PI3 (pH 9.18) showed lower expansion (⁎ΔL 6.90 mm) and higher expansion ratio (⁎ΔL 26.29 mm), respectively, after rehydration of freeze dried sample (p<0.05). From the application of SN2 (potato starch) and PI (0.5%-2.0% Na-pyrophosphate) to freeze dried sundae manufacturing, higher rehydration stability of more than 91.5% was obtained. These results suggested that potato SN and treatment of PI with Na-pyrophosphate is useful for desirable rehydration stability of freeze dried sundae.

• 한국세라믹학회지
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• 제35권10호
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• pp.1085-1093
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• 1998

Amorphous alumina powder prepared by the fast calcination of aluminum trihydroxide(Al(OH)3 gibbsite) for 0.5 second at 580$^{\circ}C$ was investigated rehydration propeties. Phase composition crystal size and mor-phology surface area pore volume and pore size distribution of pesudo-boehmite and bayerite crystals changed with temperature time water/alumina ratio and particle size when amorphous alumina rehydrated with water. Phase compositions were examined with XRD and DTA and crystal sized morphologies were investigaed with SEM and TEM. Also rehydration properties of amorphous alumina were in-vestigated by measuring the surface area pore volume and pore size distribution.

• 한국식품과학회지
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• 제21권1호
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• pp.145-148
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• 1989

건조표고버섯의 품질을 향상시키기 위해 열풍, 원적외선 및 냉동 건조시 건조조건이 품질에 미치는 영향에 대해 조사하였다. $45-70^{\circ}C$ 범위에서 열풍건조시 온도가 증가할수록 부피유지율은 높았으나 복수율은 낮았으며 5'-GMP 함량은 $50^{\circ}C$에서 건조한 것이 가장 많았다. 원적외선 전조는 같은 온도에서의 열풍건조에 비해 복수율은 높았으나 부피유지율이 낮았다. 냉동건조시 냉동속도에 따른 부피유지율의 차이는 뚜렷하지 않았지만 복수율은 $-18^{\circ}C$에서 냉동시킨 것이 가장 높았으며 건조속도에 의한 영향은 건조속도가 빠를수록 복수율이 증가하였다. 또한 냉동속도와 건조속도가 빠를수록 5'-AMP, 5'-GMP 와 5'-XMP 함량이 모두 증가하는 경향이었다.

• Journal of Pharmaceutical Investigation
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• 제31권1호
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• pp.43-47
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• 2001

Sterically stabilized liposomes (SSL) have been introduced for longer circulation in blood than conventional liposomes (CL). However, there are a couple of problems in SSL preparation due to the instability of phospholipid and the degradation of drug in aqueous conditions. To solve these problems, it is necessary to go through lyophilization process. Therefore, in this study, effects of lyophilization on SSL were evaluated for physical characteristics changes upon rehydration of lyophilized SSL such as the particle size, efficiency of drug entrapment, turbidity and drug release. SSL containing streptozocin, a water-soluble anticancer drug as a model compound, were prepared with DSPC and DSPE-PEG 2000. The size was controlled to 100 nm by extrusion with polycarbonate membrane, and sucrose was used as a cryoprotectant for lyophilization at the 1:3 (lipid:sucrose) ratio. Upon rehydration of lyophilized SSL, the average size was in the range of $50{\sim}200\;nm$ which is adequate for longer circulation in blood, and the encapsulation efficiency was kept as its initial state. Rehydrated SSL were not adsorbed to rat plasma protein and revealed a similar drug release profile to that of fresh SSL before lyophilization. Therefore, lyophilization could be introduced efficiently to overcome aqueous instability problems of SSL.

• 산업식품공학
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• 제21권1호
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• pp.29-35
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• 2017

본 연구에서는 건해삼의 재수화 반복횟수에 따른 해삼의 크기 및 조직감 변화와 재수화 반복횟수를 달리한 해삼 병조림 레토르트 제조 시, 4주간의 저장기간에 따른 품질변화를 측정하였다. 재수화 반복횟수가 증가할수록 해삼의 길이와 부피, 무게 모두 유의적으로 증가하였으며, 5회 재수화 반복 시 최대 팽윤도를 보였다. 레토르트 병조림 가열처리 시 열전달 기작은 대류로서 냉점은 유리병 형상의 기하학적 위치보다 하단에서 측정되었고, 총 가열공정 시간(TTT)는 24분으로 산출되었다. 본 가열공정을 적용한 레토르트 해삼 병조림의 가열 직후 및 저장기간에 따른 크기와 조직감 변화는 저장 1주차까지 유의적으로 변화하다가 저장 1주차부터 4주차까지 재수화 반복횟수에 관계없이 모든 실험군에서 일정한 경향을 보였다. 건해삼의 재수화 시 최대 팽윤도에서의 크기와 재수화율 및 조직감은 길이 100.86 mm, 부피 38.62 mL, 무게 41.05 g, 재수화율 6.39, 경도 $249.19g_f$, 씹힘성 4.05 mJ로 산출되었다. 이는 해삼 레토르트 제품 제조 시, 재수화 공정의 반복횟수에 관계없이 레토르트 가열처리 이후 저장기간 중 해삼의 크기와 조직감에서 동일한 값을 보이기 때문에, 레토르트 가열처리 전 재수화 1회 공정의 간편함으로 전통적인 방법 대비 짧은 재수화 공정을 기대할 수 있으며, 부가적으로 미생물학적 안전성과 소비자들의 간편한 취식 또한 기대할 수 있다.

• 산업식품공학
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• 제23권3호
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• pp.217-222
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• 2019

다시마를 첨가한 건어묵 면의 수분함량의 평균값은 3.71±0.12%이었으며 수분활성도는 0.185-0.332로 다시마 분말함유량이 증가할수록 수분활성도가 낮아졌다. 재수화도는 다시마 분말함유량이 3%와 5%일 때, 각각 1.49, 1.77 g water/g solid로 대조군에 비해 증가하였다. 색도 측정결과 녹색계열의 다시마 분말함유량이 증가할수록 명도, 적색도 및 황색도 값이 낮아지는 결과를 볼 수 있었다. TPA를 이용한 조직감분석에서는 다시마 분말의 함유량이 증가할수록 탄력성은 증가하였고 경도와 씹힘성이 낮아졌다. 관능검사 결과로 5% 다시마 분말을 첨가한 어묵 면이 조직감, 맛, 전체적인 기호도 평가에서 가장 높게 나타났으며 면발의 단단함에 대한 강도에서는 다시마 분말의 함량이 많아질수록 낮은 결과를 나타내었다.

• 한국식품영양과학회지
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• 제39권7호
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• pp.1024-1029
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• 2010

폴리에틸렌글리콜(PEG) 4,000을 20, 30, 40% 농도로 처리하여 백년초와 알로에 절편을 건조한 후, 열풍건조와 동결건조 처리된 시료와 복원율, 색도, 관능평가 등을 비교, 분석하였다. 건조시간에 따른 탈수 양은 두 시료 모두 PEG의 농도가 높을수록 탈수효율이 좋았다. 복원율에서는 열풍건조와 동결건조 처리 시료보다 PEG 처리 시료가 더 높은 복원율을 가졌다. 색도에서는 동결건조와 유사하였고 열풍건조보다는 우수하였다. 관능평가에서는 열풍건조나 동결건조보다 PEG 처리한 시료가 더 우수하였다. 따라서 본 연구 결과, PEG를 이용한 백년초와 알로에 절편의 건조는 시료의 세포파괴를 최소화하고 신선한 시료 본래의 상태로 복원될 수 있는 매우 효율적인 건조방법이라고 판단되며, 건조된 제품을 향후 기능성화장품 원료 등으로의 활용이 가능하다고 판단된다.