Processors of aseptically packaged juice-based beverages must adequately heat their product before packaging it in order to be sure that they have “killed” the microorganisms which may be present in the unprocessed beverage. (9 marks total)
A juice processing operation uses steam to heat the fruit juice up to a temperature of 96°C prior to packaging it in drink boxes. They need to heat 3,250 kg of apple juice (10.5% solids) from an initial storage temperature of 39°F to its heat treatment temperature. How much saturated steam at 617.8 kPa would be needed for this task (to the nearest kg)? In this case, the condensate is to be discharged from the process without any further cooling to recover any of its heat and is returned to the “steam plant” where it is reheated and turned back into steam.
How much steam is required per batch of product (see description in Part a) if the condensate is discharged from the process after being cooled to 75°C to use some of its heat in the process? Express your answer to the nearest kg.
How much steam is saved by recovering some of the heat in the condensate (i.e., the difference between the process as outlined in part a as compared to the process in part b). Express your answer to the nearest of kg of steam.