Home Cheese starters Donate support Site Probiotics Cheese yield Cheese quality Cheese science Italian cheese Anti-microbial  proteins Phages Primary production Ice cream Wine Calculators Harvard referencing Packaging Jobs

# F0, B* and C* for ESL Dairy products.

Author
Topic Search   Topic Options

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Topic: F0, B* and C* for ESL Dairy products.
Posted: 30 Apr 2013 at 10:17pm

I have included an update on recent work with ESL dairy products on the site news page.

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Posted: 04 Nov 2011 at 9:43pm
Hi Marvin

Welcome back to the forum. I have responded to your prion query elsewhere. The heat treatments involved in UHT processing are unlikely to have much effect on prions; I have not seen any data suggesting milk as a source of prions.

Your observation re turbulent flow is essentially correct.

Guests
Guest Group

Post Options    Thanks(0)    Quote  Reply Posted: 03 Nov 2011 at 11:13am
Great calculator! Re flow, divide B* by 2 because most flow is turbulent and particles travelling slower than fastest flow point?
Would u know what UHT does to prions?

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Posted: 02 Nov 2011 at 9:50pm
After some weeks of testing, a calculator for determining  F0, B* and C* for ESL Dairy and other UHT treated products has been added. I have tested several methods for predicting lactulose levels and have found that the relationship developed by Dr Roeland Rombaut and his colleagues, using an activation level of 134.65 kJ/mole, to work well. The calculator can be accessed at

Note the B* values may (highly likely!) 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.

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Posted: 22 Oct 2011 at 11:01pm
I have been asked to add a facility to estimate the effect of UHT-processing on lactulose and have added this to the On Line calculator that I am now testing.

 Lactulose has been calculated using the estimated equivalent time (s) at 135° C  and the relationship developed by Browning et al. (2001).Happy to let a few users test out the new calculator if they agree to provide me with some feedback on ease of use and any problems found. If interested Email me including spreadsheet testing in the title.

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Posted: 19 Oct 2011 at 11:40pm

I have produced a spreadsheet using Simpson's rules that calculates F0, B* and C* for ESL Dairy and other UHT treated products. Simpson's rules give more accurate estimates of the area under the typical time/lethality plot than spreadsheets programmed using the trapezoid rule.

This spreadsheet uses advanced Excel programming (basically using conditional arguments). Users can also use a simple trapezoid rule macro to compare calculations performed using both methods of numerical integration.
I have also developed a trapezoidal based spreadsheet for doing this On Line.
These spreadsheets will be available by mid-November

Joined: 01 Sep 2009
Location: N. Ireland
Status: Offline
Points: 390
Post Options    Thanks(0)    Quote  Reply Posted: 23 May 2011 at 8:42pm
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".