• Title, Summary, Keyword: osmotic dehydration

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Mass Transfer Characteristics and Browning Inhibition by Osmotic Dehydration of Mushrooms (양송이의 삼투압 건조에 따른 물질이동 특성과 갈변억제)

    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.5
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    • pp.903-907
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    • 1998
  • Mass transfer characteristics during osmotic dehydration of mushrooms(Agaricus bisporus) in sugar solution were studied as a function of sugar concentration, immersion time and temperature, and the effect of osmotic dehydration on browning inhibition of air-dried mushrooms was also evaluated. Increasing the sugar concentration, immersion time and temperature increased moisture loss, sugar gain, molality and rate parameter. The changes of sugar gain and rate parameter were more significantly affected by concentration than by temperature of sugar solutions, while 1$0^{\circ}C$ increase in temperature or 10 Brix increase in concentration had the same effect on water loss. Water loss, sugar gain, molality were rapid in the first period of osmotic dehydration especially in the case of higher concentration and temperature of sugar solutions. Effects of osmotic dehydration in sugar solution(60 Brix, 8$0^{\circ}C$) with 18 min of immersion time(O.D.=0.099) rior to air dehydration on browning inhibition of dried mushrooms were more significant than blanching in water(8$0^{\circ}C$) with the same immersion time(O.D.=0.330) and the control (O.D.=0.559).

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Optimization of Osmotic Dehydration for the Manufacturing of Dried Banana (건조바나나 제조를 위한 삼투건조공정의 최적화)

  • 윤광섭;장규섭;최용희
    • Korean Journal of Food Preservation
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    • v.6 no.1
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    • pp.55-60
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    • 1999
  • A three variables by three level factorial design and response surface methodology were used to determine optimum conditions for osmotic dehydration of banana. The moisture loss, solid gain, weight loss and reduction of moisture content after osmotic dehydration were increased as temperature, sugar concentration and immersion time increased. The effect of concentration was more significant than those of temperature and time on mass transfer. Color difference and titratable acidity were decreased by higher concentration. Sweetness was increased by increasing sugar concentration, temperature, immersion time during osmotic dehydration. The regression models showed a significant lack of fit (p>0.5) and were highly significant with satisfying values of R2. To optimize osmotic dehydration, based on surface response and contour plots, superimposing the individual contour plots for the response variables. the optimum conditions for this process wire 26$^{\circ}C$, 44 $^{\circ}$brix and 2 hrs for moisture content, sweetness and color difference are less than 72%, 24 obrix and 10 degree.

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Utilization of Osmotic Dehydration as Pretreatment prior to Drying (건조전처리로서 삼투건조의 이용)

  • 윤광섭
    • Korean Journal of Food Preservation
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    • v.5 no.3
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    • pp.305-314
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    • 1998
  • In the drying process, many undesirable physicochemical changes occur that influence dried food product qualities. Pretreatments method is used to reduce the deterioration of dried food product qualities such as color, flavor, texture, rehydration ability and retention of nutrients. The methods of pretreatments are blanching, chemical treatment and osmotic dehydration. Osmotic dehydration is a water removal process which is based on placing foods in a concentrated osmotic solution or in a dry osmotic material. A large number of process variables have a significant effect on process and final product quality. In order to improve final product quality it is necessary to know the role of each process variable and understand the mecanisms throughout the process. Osmotic dehydration is a valuable processing tool with great future in minimal processing of fruits and vegetables.

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Effect of Combined Osmotic Dehydration and Hot-air Drying on the Quality of Dried Apple Products (삼투건조와 열풍건조의 조합이 사과 건조제품의 품질에 미치는 영향)

  • Choi, Hee-Don;Lee, Hae-Chang;Kim, Yun-Sook;Choi, In-Wook;Park, Yong-Kon;Seog, Ho-Moon
    • Korean Journal of Food Science and Technology
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    • v.40 no.1
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    • pp.36-41
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    • 2008
  • This study was conducted to investigate the effects of combined osmotic dehydration and hot-air drying on the quality of dried apple products. Apple cylinders were steeped in 30% and 50% sucrose solutions at different steeping times. During the osmotic dehydration, as the concentration of the sucrose solution and steeping time increased, weight reduction and water loss increased, and the solid gain showed similar results. Osmotic dehydration in the sucrose solutions was followed by hot-air drying at 50 and $70^{\circ}C$. The experimental data were fitted successfully using the modified Page model. At the drying temperature of $50^{\circ}C$, the drying time increased from 4.15 hr for the control to 5.78 hr and 6.42 hr for the 30 and 50% sucrose solution treatments, respectively. Similar results were shown at the $70^{\circ}C$ drying temperature. The k and n values of the apple cylinders decreased by osmotic dehydration, and the k and n of the apple cylinders steeped in the 50% sucrose solution were lower than those of the samples steeped in the 30% sucrose solution. The qualities of the dried apple products were compared to samples that did not undergo osmotic dehydration. The shrinkage and rehydration capacity of the apple products decreased via osmotic dehydration, and decreased as the concentration of the sucrose solution increased. The compressibility ratios of the apple products to raw apple cylinders increased by osmotic dehydration, and increased as the concentration of sucrose solution increased. The sensory evaluation results for the apple products rehydrated in yoghurt indicate that osmotic dehydration greatly enhances the palatability of apple products in terms of appearance, taste, and texture.

Changes of Quality in the Osmotic Dehydration of Cherry-Tomatoes and optimization for the Process (방울토마토의 삼투건조시 품질의 변화와 공정의 최적화)

  • 윤경영;윤광섭;이광희;신승렬;김광수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.5
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    • pp.866-871
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    • 1997
  • This study was carried out to determine the effect of osmotic dehydration as pretreatment on the qualities of dried cherry-tomatoes. The weight reduction and solid gain in osmosed cherry-tomato were increased by increasing sugar concentration, immersion temperature and time; among three parameters, the immersion temperature affected more than sugar concentration and immersion time did. The moisture content was decreased as increasing sugar concentration, immersion temperature and time, and it was the lowest at the osmotic conditions of 7$0^{\circ}C$, 60$^{\circ}$Brix and 11hr. To determine the optimum processing condition by RSm, the polynomial optimum models were established. The regression models was significant (p<0.05). It was used contour plots to optimize osmotic dehydration. The optimum condition for osmotic dehydration as pretreatments for drying of cherry-tomatoes were immersion temperature of 47~53$^{\circ}C$, sugar concentration of 39~43$^{\circ}$Brix, and immersion time of 7hr, in which process conditions were 78~86% moisture content, 8.5~10$^{\circ}$Brix sugar content and 80~86% weight reduction.

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Effects of Osmotic Dehydration on Drying Characteristics of Kiwifruits (키위의 건조특성에 미치는 삼투처리의 영향)

  • 윤광섭;홍주헌
    • Korean Journal of Food Preservation
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    • v.6 no.3
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    • pp.319-323
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    • 1999
  • This study was conducted to minimize the deterioration of dried kiwifruit quality. Osmotic dehydration was carried out as pretreatment before drying. After the kiwifruits were pretreated under optimized osmotic dehydration conditions, they were dried by three drying methods(hot air drying, vacuum drying, freeze drying). Hot air drying and vacuum drying were superior to freeze drying in the drying speed. But vacuum and freeze drying preserved more vitamin C than hot air drying. Also, osmotic dehydrated kiwifruit kept better quality than nontreated kiwifruit. Diffusion coefficient which describes moisture transfer, was high in drying process pretreated with osmosis. The changes of vitamin-C followed the second-order reaction rate equation with high RE, respectively.

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Effects of Salt Addition in Sugar Based Osmotic Dehydration on Mass Transfer and Browning Reaction of Carrots

  • Chang, Moon-Jeong;Han, Myung-Ryun;Kim, Myung-Hwan
    • Preventive Nutrition and Food Science
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    • v.8 no.3
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    • pp.230-234
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    • 2003
  • Mass transfer characteristics during osmotic dehydration of carrots were studied as functions of immersion temperature and time, and sugar and salt concentrations. The effect of osmotic dehydration on the degree of browning of air-dried carrots was also evaluated. Increasing the immersion temperature and time, sugar concentration, and salt addition increased water loss, sugar gain, molality and rate of dehydration. The water loss and increases in solids, and molality were rapid in the beginning of the process and then increased slowly during remainder of the process. Increasing 1 or 2% salt concentration in the 40$^{\circ}$Brix sugar solution at 6$0^{\circ}C$ increased water loss and solid gain. Salt addition was not able to significantly affected on water loss and solid gain compare to temperature (40~8$0^{\circ}C$) and sugar concentration (20~60$^{\circ}$Brix) changes due to the low salt concentration. A minimum degree of browning of the air-dried carrots (O.D. = 0.048) could be achieved using binary solutions (40$^{\circ}$Brix sugar solution with 2% salt addition) with 24 min of immersion time compared to control (O.D. = 1.308) or blanching with 24 min of immersion time (O.D. = 0.174).

Mass Transfer during Osmotic Dehydration of Carrots and Its Effect on Browning Reaction (당근 삼투압 건조시 물질 이동과 갈색화 반응에 미치는 효과)

  • Kim, Myung-Hwan
    • Korean Journal of Food Science and Technology
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    • v.21 no.2
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    • pp.307-312
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    • 1989
  • Internal mass transfer during osmotic dehydration of carrots in sugar solutions was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration and blanching on browning reaction of vacuum dried carrots(3% MC: wet basis) was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in first 4 min and then levelled off. The rate of sugar gain and molality changes on temperature was significant in lower concentration$(20^{\circ}\;Brix)$ compared to higher concentration$(60^{\circ}\;Brix)$. The changes of rate parameter were affected by concentration than by temperature of sugar solutions. Moisture loss during osmotic dehydration using a sugar solution $(60^{\circ}\;Brix,\;80^{\circ}C)$ with 20min immersion time was 55.7%. Effect of osmotic dehydration and blanching before vacuum dried to 3% MC(Wet basis) on browning reaction was significant. Minimum browning reaction during vacuum drying was carried out using pretreatments such as osmotic dehydration in sugar solution$(40^{\circ}\;Brix,\;80^{\circ}C)$ with 16 min immersion time(O.D.=0.09) and blanching with 12 min immersion time at $80^{\circ}C$(O.D.=0.31) compared to control(O.D.=1.59).

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Mass transfer Characteristic during Osmotic Dehydration of Ginger and Its Effect on Quality (생강 삼투압 건조 시 물질이동 특성과 품질에 미치는 효과)

  • Kim, Myung-Hwan
    • Applied Biological Chemistry
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    • v.41 no.5
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    • pp.372-376
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    • 1998
  • Internal mass transfer during osmotic dehydration of gingers in sugar solution was examined as a function of concentration, temperature and immersion time of those solutions using moisture loss, sugar gain, molality and rate parameter. Influence of osmotic dehydration on browning reaction and texture properties of air dried rehydrated was also evaluated. Increasing the concentration and temperature of sugar solutions increased moisture loss, sugar gain, molality and rate parameter. Water loss and sugar gain were rapid in the first 3 min and then changed gentle slope. Moisture loss during osmotic dehydration using a sugar solution $(60\;Brix,\;80^{\circ}C)$ with 18 min immersion time was 40.05 g moisture/100 g wet ginger which was 52% reduction of initial moisture content in ginger (83.02%, wet basis). The changes of rate parameter were more affected by temperature than by concentration of sugar solution. Minimum browning degree (O.D.=0.027) was carried out by osmotic dehydration in sugar solution $(40\;or\;50\;Brix,\;80^{\circ}C)$ with 15 min immersion time compared to control (O.D.=0.132). Influence of osmotic dehydration on puncture forces of 3 min rehydrated ginger in boiling water were $22{\sim}34%$ of reduction, while blanching treatment had not affected compared to those of control.

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Quality Characteristics of Hot-Air and Freeze Dried Apples Slices after Osmotic Dehydration (사과의 삼투압처리 후 열풍 및 동결건조에 따른 품질 특성)

  • Kim, Gi-Chang;Lee, Sun-Young;Kim, Kyung-Mi;Kim, Young;Kim, Jin-Sook;Kim, Haeng-Ran
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.6
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    • pp.848-852
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    • 2011
  • The aim of our study was to develop drying process of apple slice. Quality characteristics of apple slices dried by hot-air and freeze drying after osmotic dehydration was investigated in different sucrose solution (20, 40, $60^{\circ}Brix$) and steeping time (2, 4, 8 hours). The weight of apple slice before and after osmotic dehydration was measured for characteristic of mass transfer. Consequently, osmotic dehydration increases weight reduction, water loss and solid gain of apple slice as the concentration of the sucrose solution and steeping time increased. Moisture contents of apples slices dried hot-air and freeze were about 3 to 7%. Hunter color L, a, b value was lower than non-treatment to osmotic dehydration of apple slice. In hot-air drying, L value decreased as the concentration of the sucrose solution and steeping time increased. The hardness increased as the concentration of the sucrose solution and steeping time increased. Contents of monosaccharide (glucose, fructose) decrease by osmotic dehydration but sucrose increased. In comparison with hot-air drying, freeze drying was high in contents of free sugar.