A batch of raw milk was tested and found to contain a bacterial population of 8xl06cfu/ml. It is to be pasteurised at noc for 33 seconds. The average D value at 52°C for the mixed population is 11 min. The z value is 10°C. i)Explain the terms "D value" and "z value". ii)Calculate how many organisms will be left after pasteurisation. iii)Hpw much time will be needed at 62°C to accomplish the same degree of lethality?

A batch of raw milk was tested and found to contain a bacterial population of 8xl06cfu/ml. It is to be pasteurised at noc for 33 seconds. The average D value at 52°C for the mixed population is 11 min. The z value is 10°C. i)Explain the terms "D value" and "z value". ii)Calculate how many organisms will be left after pasteurisation. iii)Hpw much time will be needed at 62°C to accomplish the same degree of lethality?

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter33: Automated Methods Of Analysis

Section: Chapter Questions

Problem 33.4QAP

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