Absorption Characteristics of Persimmon Powder Depending on Temperature Changes and Drying Methods

건조방법과 온도변화에 따른 감 분말의 흡습특성

  • 이원영 (상주대학교 식품생물공학과) ;
  • 김종국 (상주대학교 식품영양학과)
  • Published : 2001.12.01

Abstract

The absorption characteristics of persimmon powder related to different drying methods and various storage temperatures was investigated. The physical properties of persimmon powder by different drying methods displayed the largest amount of porosity in the freeze-dried sample, and the smallest in hot air dried sample. Equilibrium moisture was reached in 6 days. Monolayer moisture contents were predicted to 0.09687~0.19712(freeze drying), 0.07820~0.18617(vacuum drying) and 0.07715~0.18056(hot air drying) g H2O/g solid respectively using the BET equation. BET equation for isothermal absorption curve showed over 0.95 R-square for all dried methods. Monolayer moisture contents were increased as storage temperature was incremented because water molecular movement was more active and there was a greater chance to clash with the absorption surface area.

감 과육 파쇄물을 열풍, 진공, 동결의 건조방법으로 건조를 행하였다. 각 건조 방법별로 감분말의 물리적 특성치인 공극률은 열풍 건조한 시료가 1.9%로 가장 작게 나타났으며, 진공건조 2.13%, 동결건조가 3.95%의 순으로 나타났다. 또한 총공극 면적 역시 동결, 진공. 열풍건조의 순으로 나타났으며 공극의 평균지름은 반대의 순으로 나타났다. 상대습도의 변화에 따른 감 분말의 평형수분함량에 도달하는 기간을 조사한 결과이다. 상대습도가 증가할수록 흡습량이 증가하는 것으로 나타났으며 저장 3일을 기점으로 그 이전에는 흡습량이 급격히 증가하다가 그 이후에는 증가폭이 둔화하는 것으로 나타났다. 또한 낮은 상대습도에서는 수분평형상태에 도달하는 시간이 짧은 반면 상대습도가 증가할수록 평형수분함량에 도달하는 시간이 길어지는 경향을 나타내었다. 온도의 변화에 있어서는 저장온도가 증가할수록 평형상태에 이르는 시간이 길어졌으며 저장상대습도에 따른 평형수분함량의 도달시간은 실험구간내 에서의 상대습도변화에서는 5일 정도에서 평형상태에 거의 다다르는 것으로 나타나 저장 적정 수분함량을 구하기 위해 단분자층 수분함량을 구한 결과는 BET식에서 동결건조한 시료가 다른 시료보다 높은 값을 나타내었고, 등온 흡습선으로서 적합도는 건조 방법별로 0.95 이상의 상관계수 값을 나타내었다.

Keywords

References

  1. J. Kokr. Soc. Hort. Sci. v.36 no.3 Classification of persimmon cultivars on the basis of horticultural traits Kim, T.C.;Ko, K.C.
  2. Korean J. Soc. Food Sci. v.16 no.4 Quality characteristics of the bread added persimmon leaves powder Kang, W.W.;Kim, G.Y.;Kim, J.K.;Oh, S.L.
  3. J. Korean Soc. Food Sci. Nutr. v.29 no.3 Changes of physicochemical properties during preparation of prepersimmon pickles Shin, D.J.;Kim, W.J.;Oh, H.I.
  4. Korean J. Soc. Food Sci. v.15 no.1 Physical and sensory characteristics of persimmon jam prepared with enzyme treated persimmon juice Kim, J.G.;Choi, H.S.;Kim, W.J.;Oh, H.I.
  5. Korean J. Dietary Culture v.10 no.4 Studies on valuable components and processing of persimmon flesh and peel Moon, K.D.;Kim, J.K.;Kim, J.H.;Oh, S.L.
  6. J. Korean Soc. Food Sci. Nutr. v.27 no.6 Optimization on organoleptic properties of Kochujang with addition of persimmon fruits Lee, G.D.;Jeong, Y.J.
  7. Korean J. Food Sci. Technol. v.27 no.5 Changes of physicochemical properties during the preparationn of persimmon pickles and its optimal preparation conditions Kim, H.Y.;Chung, H.J.
  8. J. Food Sci. v.61 Moisture sorption isotherms of canola meals and applications to packaging Diosady, L.L.;Rizvi, S.S.H.;CAI, W.;Jagdeo, D.J.
  9. J. Food. Technol. v.6 Dehydration of food products Holdswotth, S.D.
  10. Pysical characteristics of food powders. In Physical Properties of Foods. Peleg, M.;Peleg, M.(ed.);E.B.Bagley(ed.)
  11. Food texture Song, J.C.;Park, H.J.
  12. Korean J. Food Sci. Technol. v.21 Changes in quality of shiitake mushroom(Lentinus edodes) by different drying methods Back, H.H.;Kim, D.M.;Kim, K.H.
  13. J. Food Sci. Technol. v.32 Dehydration of mushroom by sun-drying, thin-layer drying, fluidized bed drying and solar cabinet drying Suguna, S.;Usha, M.;Sreenarayanan, V. V.;Raghupathy, R.;Gothandapani, L.
  14. Adsorption of food-born phenolic acids on activated carbon and desorption by supercritical carbon dioxide Lee, W.Y.
  15. J. Food Sci. v.50 Effect of temperature on the moisture sorption isotherms and water activity shift of two dehydrated foods Labuza, T.P.;Kaanane, A.;Chen, J.Y.
  16. J. Food Technol. v.19 Technical note: Correlation of BET monolayer moisture content in foods with temperature Iglesisa, H.A.;Chirife, J.
  17. The study of fluid and absorption properties for model powder food The study of fluid and absorption properties for model powder food Kim, D.W.
  18. Food properties handbook Shafiur, R.
  19. J. Food Sci. v.50 Effect of four drying methods on the quality of intermediate moisture lowbush blueberries Yang, C.S.T.;Atallah, W.A.
  20. J. Food Sci. v.60 Moisture sorption characteristics of freeze dried blueberries Lim, L.T.;Tang, J.;He, J.