 In this module we will again talk about the medium sterilization, but actually in this module we will take, we will talk about the rapid method for the designing of the sterilization cycle following by the Richard methods. So, as concern the Richard 1968 he proposed a rapid method for the designing of the sterilization cycle avoiding the time consuming graphical integration as we have seen ever our previous module. So, the method assumes that all this pore destruction occur at the temperature above 100 degree Celsius and that those part of the heating and the cooling cycle that is above 100 degree Celsius are linear. So, when we go beyond 100 degree Celsius it mean the destruction is linear. So, the both these assumptions reasonably valid and the technique loses very little in accuracy and gain considerably in simplicity. Furthermore, based upon these assumptions Richard has presented a table of the del factors for Bacillus stereothermophilus pores which could be obtained in heating and cooling a broth up to and down from the holding temperature. If we say that the holding temperature is 101 to 130 degree Celsius based upon the temperature change 1 degree Celsius per minute. I mean when we go beyond 100 to 130 as we have discussed in later modules in our previous module about that 30 is the suitable number to increase the temperature. So, if we go and rise the temperature from 100 degree Celsius to 130 degree Celsius overall there is a 30 increment and per minute rise is 1 degree Celsius then this information is also we can see in our next when we know that the specific death rate for Bacillus stereothermophilus pores are different temperature ranges. So, in this table we can see that this is the temperature if we go increasing the temperature from 100 to 130 just by increasing the 1 and the specific death rate is you can we can see here that 0.019 and then 0.02125 and 0.032, 0.04 and so on and then when we calculate the del factor. So, there is also a gradually increase in the del factors. So, if we go from 100 degree Celsius to 115 degree Celsius the rise in the specific death rate from 0.019 to 0.666 as concerned the del factors you can see here that 0.044 in case of 101 and 3.154 in case of a temperature when there is a 115. So, when we go from 160 to 130. So, the specific death rate gradually increase and maximum reached up to 17.524 as concerned the del factors we can see here that that rises up to 90.591 mostly when we say that in autoclave process when the temperature is mostly kept at 121 degree Celsius then the death rate is 2.538 at that time the del factor is 12.549 just keep in mind this situation when the temperature is 121 degree Celsius and specific death rate which we called as K and this is the temperature and this is the delta factor. So, if we just focus on this then we can easily understand the next. So, the rate of temperature change from 1 degree per minute the del factor of heating and cooling as we seen that directly from the table. So, the temperature change deviate from 1 degree per minute. So, the del factor may be altered by the simple promotion. So, as the temperature increase del factor also increase with some specific proportion. So, if you take an example that if the fermentation growth were heated from 100 degree Celsius as I have already pointed out that try to focus on 121 degree Celsius. So, if we say that 100 degree Celsius to 1 day in 30 minute and the cooling from 121 to in 17 minute. So, the rise in temperature in temperature takes more time rather to be the cooling in just an example. So, if the rise time is 30 minute and the down and cooling time in 17 minute. So, then the del factor for heating and cooling cycle may be determined by this. So, from the table as we have seen if the change in the temperature has been 1 degree per minute then the del factor for both heating and cooling cycles as we have seen that when we talking about the 121 degree Celsius from the table then the del factor was 12.549. But the temperature change in the heating cycle was 21 degree in 30 minutes. So, therefore, the del heating this is the del factor multiply by the time need utilize to raise the temperature up to 120 degree Celsius this is the term basically to 121 degree Celsius. So, in 30 minute the overall rise in the temperature in 21 degree. So, just by dividing this 21 degree then the del factor of heating actually is 17.93 by the same case when we are talking about the del cooling. So, as we seen in our previous example if the rising time from 100 degree Celsius to 121 degree is 30 minute and if we say that the cooling time is 17 minute. So, the cooling from 121 degree Celsius to 100 degree Celsius and the cooling time is 17 minute then the del factor easily. So, the del factor at 121 degree Celsius multiply by the time and then the overall decrease in the temperature then 10.16 is actually the del factor for the cooling cycle. So, having calculated the del factor for heating in the cooling periods the holding time at constant temperature may be calculated as we have discussed in this modules. So, by this way when we kept the temperature constant then we can calculate the increase and the decreasing temperature mean the heating and the cooling del factors.