F0, B* and C* for ESL Dairy Products
Printed From: Dairy Science and Food Technology
Category: Site calculators and spreadsheet queries
Forum Name: Spreadsheet and site calculators
Forum Description: Support queries about calculators and spreadsheets downloaded from Dairy Science and Food Technology website or the ice cream mix subscription service
URL: https://www.dairyscience.info/forum/forum_posts.asp?TID=269
Printed Date: 19 Apr 2024 at 1:25pm
Software Version: Web Wiz Forums 12.03 - http://www.webwizforums.com
Topic: F0, B* and C* for ESL Dairy Products
Posted By: formula123
Subject: F0, B* and C* for ESL Dairy Products
Date Posted: 23 May 2011 at 8:40pm
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I received the query below yesterday: "Can you please provide the calculator (Fo calculator) to calculate F0, B* and C* for ESL Dairy products. I am particularly interested in custard, stabilised thickened cream and milk".
Need much more information before I can do this? Please provide some more information.
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Replies:
Posted By: formula123
Date Posted: 26 May 2011 at 10:12pm
| I will provide a spread sheet that enables Fo, B* and C* to be calculated for extended shelf life dairy products within the next few weeks. |
Posted By: formula123
Date Posted: 02 Nov 2011 at 9:43pm
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The free On Line calculator to determine F0, B*, C* values and predicted lactulose concentrations following the UHT-treatment of milk has been http://www.dairyscience.info/uht123.asp - added .
Note the B* values will usually require adjustment to allow for for the flow conditions in the heat processing plant. This usually means reducing them by a factor of 2 (Tran et al, 2008). I will add a tutorial explaining how to do this.
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Posted By: Ryan
Date Posted: 10 Nov 2011 at 6:55am
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I'm sorry Mr Michael I Want to ask how to calculate B* and C* if i used retort what formula should i used my product is dairy, and my parameter retort is 125 C & 7 menit Thank you for your attention I'm very need your help |
Posted By: formula123
Date Posted: 10 Nov 2011 at 9:25pm
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I intend to add an article on ESL and UHT milk and will
cover the calculation of C* and B* over the next month or so. B*and C* are calculated in a similar way to F0 except that
the reference temperature, z-value and the time taken to give a value of 1 are
different. B*=1 is obtained by using a z-value of 10.5 °C, a reference
temperature of 135 °C and a holding time equivalent to 10.5 seconds and
represents a log 9 reduction in thermophilic spores. The C* value measures the chemical effect of high
temperature processing and is concerned with thiamine destruction. A reference
temperature of 135 °C, a Z-value of 31.4 °C and a holding time of 30.5 seconds
are required to give a C*=1; this corresponds to a 3 % reduction in the
thiamine concentration in the food being processed. I think you want to calculate the B* and C* values resulting
from heating a food in a retort at 121°C for 7 minutes? B* and C* values
are normally used for UHT processing and I don’t understand why you are using
them for a product produced at a much lower temperature. To calculate B* enter the following into Excel: =10^((121-135)/10.5)*7*60/10.1. Note the 7 minutes have
been converted to seconds. To calculate C* enter the following into Excel: =10^((121-135)/31.4)*420/30.5. |
Posted By: formula123
Date Posted: 11 Nov 2011 at 7:42pm
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Ryan Apologies. I misread your post, you wrote 125 not 121C. Please replace the 121 with 125. Sorry if I have confused you. |
Posted By: mstrange
Date Posted: 12 Nov 2011 at 11:23pm
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Could you change your C* calculator to allow cals of a few holding times eg 3 min at say 123 C and say 10 secs at 90C? This would be much used by us.  Please! |
Posted By: formula123
Date Posted: 13 Nov 2011 at 9:29pm
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Welcome back, and thanks for the suggestion. Prior to Ryan's post I would not have anticipated anyone wanting this sort of calculator. I will think about your request and let you know what I decide. I suppose I wonder just how much use this calculator would be?
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Posted By: formula123
Date Posted: 14 Nov 2011 at 9:02pm
| I have added a highly flexible B*and C* calculator that also calculates F0 values for UHT-treated milk. The calculator allows users to set time intervals in either seconds or minutes at predetermined temperatures. This calculator along with the other two thermal processing calculators should enable the lethal effects of most thermal processes to be evaluated. The calculator is at http://www.dairyscience.info/uht1.asp - www.dairyscience.info/uht1.asp . |