• Korean Journal of Food Science and Technology
• /
• v.16 no.2
• /
• pp.206-210
• /
• 1984

Heat penetration pattern of canned oyster mushroom(Pleurotus astreatus) was monitored for processing variables-can size, heating temperature and solid fill fraction, and its effects on sterilization condition was reviewed. The $f_h$ value decreased sharply with decrease of solid fill fraction and then became stable from certain solid fill fraction unique to can size. Heat penetration was a little faster at higher heating temperature with lower $f_h$ value. As viewed from $f_h$ value, convection started at higher solid fill fraction with higher length/diameter ratio, and $f_h$ values decreased to about 1.0 with decrease of solid fill fraction. From standpoint of overall cost, retorting time and energy consumption, solid fill fraction of 3/5 was optimum for all can sizes considered.

• Korean Journal of Food Science and Technology
• /
• v.12 no.3
• /
• pp.170-175
• /
• 1980

A mass production of chestnut necessiates the development of economic long-term storage method. The main objective of this study was to confirm the technical aspect of the chestnut storage method which was developed by two year project and to review the method of commercial application. The chestnut used for the experiments were separated in brine $(5.5{\sim}6.0^{\circ}\:B{\acute{a}}ume)$ into matured and unmatured lots and fumigated with $CS_2$ at a 5 $lb/27\;m^3$ level for $25{\sim}30\;hrs.$ The chestnuts were packed in wooden boxes with sawdust (50% moisture) in the ratio of 1 : 1 by volume. The boxes were stored in the cold room $(1{\pm}1^{\circ}C,\;85{\sim}95%\;RH)$ and the cellar ($0{\sim}10^{\circ}C$, controlled only by circulating night cool air). The results obtained were as follows: 1. Fully matured chestnut could be successfully preserved $8{\sim}9\;months$ at a l0% decay level in the cold room and $4{\sim}5\;months$ months in cellar. 2. Immatured chestnuts wire inferior to the matured in storage stability. At the maximum storage period, its storage life was two months shorter. 3. The heat transfer equation of piled chestnuts with sawdust can be suggested as $T_{\infty}-T_0=(T_{\infty}-T_0){\cdot}10^{-t/320}$ and j and $f_h$ values were 1 and 320 min, respectively. 4. The chestnuts in the package of storage unit had longer shelf life than naked chestnut during the retail distribution at ambient temperature.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.39 no.7
• /
• pp.591-598
• /
• 2015

Pool boiling heat transfer coefficients of a LiBr solution were obtained for seven low fin tubes having different fin pitch and fin height. The test range covered saturation pressure from 7.38kPa to 101.3kPa, heat flux from $20kW/m^2$ to $40 kW/m^2$ and LiBr concentration from 0% to 50%. The optimum fin geometry for the present experimental range turned out to be 26 fpi with 0.18 mm fin height.The advantage of added heat transfer area and the disadvantage of slower bubble growth and departure appear to have yielded an optimum fin pitch. The heat transfer coefficient decreased as saturation pressure decreased and Libr concentration increased. The reason may be attributed to the low saturation pressure, which increased the bubble departure diameter and decreased the bubble departure frequency. As the LiBr concenreation increased, the saturation temperature increased and the mass diffusion rate decreased, which resulted in a reduced heat transfer coefficient. The heat transfer coefficients of the low fin tube were greater than those of the smooth tube. Correlations were developed based on the present data.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.14 no.4
• /
• pp.359-364
• /
• 1985

Being used the three kinds of aqueous solution of tobacco extracts as a new experimental material, experiment and theoretical analysis are performed. Measurements are made with a apparatus designed and constructed by the author.The average diameter of the ice crystals is 0.04-0.1cm between 0.2 and $0.6^{\circ}C$ of the subcooling temperature of the solution. The growth rate of ice crystals in direction of axies A, $V_a$ is in proportion to the subcooling temperature, viz; $v_a=0.058{\Delta}t_b,\;where\;{\Delta}t_b<0.1^{\circ}C$ The growth rate of ice crystal have to be considered not only the mass diffusion and the heat transfer of rate controlling but also the process in ice crystallization. The growth rate of ice crystal is found to be independent on the concentration of the solution and a diameter of ice crystal.