摘要:

ABSTRACTAlong with the grade of intactness, fruit firmness is an important factor for the quality criteria on which the consumers acceptance for apples is based.Two methods for measuring the fruit firmness (a destructive one and a nondestructive one) are compared. the nondestructive method uses modal analysis to define the lower vibration modes. This enables the use of the 3‐media elastic sphere model developed by Cooke and Rand (1973) to calculate the dynamic elastic moduli of the whole apples. the destructive method determines the dynamic elastic moduli of cylindrical samples of apple tissue. This method is based on the vibration characteristics of a mass‐spring‐damper system. This system consists of a cylindrical apple sample and a mass. Measuring the direct transfer function of this one‐degree‐of‐freedom system results in values of its system parameters, from which the dynamic elastic moduli of the specimen can be calculated.The results of the two methods applied on Golden Delicious apples were compared, and the suitability of each model wa

ISSN:0145-8876    

DOI:10.1111/j.1745-4530.1988.tb00010.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTCircular grain dryers in which grainflow is continuous and airflow is in radial direction are widely used as on‐farm grain dryers. A concurrentflow drying model is adapted to the crossflow drying of the moving bed of grain. the simulated air and grain temperatures and moisture contents of wheat and corn samples were compared to the experimental drying of these grains in laboratory dryers. the results show that the model can be used to describe temperature of grain within 1°C and moisture content within 0.3% w

ISSN:0145-8876    

DOI:10.1111/j.1745-4530.1988.tb00011.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTConnective heat transfer coefficient at the fluid‐particle interface was determined for cut green beans in 303 × 406 cans processed in an agitated retort (FMC Steritort) by measuring the temperature of an aluminum bean and that of the surrounding Newtonian fluid. Four retort reel velocities, two sizes of aluminum beans, and six particle/fluid ratios were employed. Several correlation forms were tested. A correlation was developed in terms of the j‐factor, Reynolds number (Re), and shape factor with an R2of 0.785. the particle's shape was a critical factor in the heat transfer correlations. the fluid‐particle heat transfer rate increased with an increase in rotational velocity of the

ISSN:0145-8876    

DOI:10.1111/j.1745-4530.1988.tb00012.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTTo study the strength advantages of pressurized cans used for food packaging, two indicators of can strength, maximum axial load and maximum external pressure, were investigated experimentally. Unbeaded 303 × 406 steel cans having several thicknesses and tempers with various internal pressures were tested. Also tested were beaded steel cans and aluminum cans with 206 × 406 dimensions. Failure of the cans was by both buckling and yielding. the results indicated that steel can thicknesses could be significantly reduced, and beading eliminated, by using internal pressure to supplement can strengt

ISSN:0145-8876    

DOI:10.1111/j.1745-4530.1988.tb00013.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

ABSTRACTOrange juice was concentrated by RO up to 50% hydraulic recovery with a polyamide membrane. Permeate fluxes and solute recoveries were determined at transmembrane pressures of 6.21 and 4.14 MPa. Pectinase treatment was required to prevent fouling and to allow Cleaning in Place procedures. Enzymatic treatment did not affect permeate flux or solute recoveries. Overall recovery of sugars, organic acids, and flavor‐volatile components was approximately 93

ISSN:0145-8876    

DOI:10.1111/j.1745-4530.1988.tb00014.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY