logistics of flash heating / Pasteurization

I'm about to give birth to my 2nd child and I will be feeding donated milk exclusively for at least the first few months (and hopefully after that also, with luck!). I'm still on the fence about whether I should Pasteurize or flash heat the milk. I have total 100% trust that my donors are all fantastic, wonderful people who would never intentionally donate milk that could harm my baby, but the key word for me is "intentionally". So I'm considering flash heating to account for anything that might be in the milk unintentionally.

For mamas out there who do this, what are the logistics? Do you pool a day's worth of milk together to heat it? A week's worth? And then do you re-freeze it or store it in the fridge until the baby can drink it? Any tips/tricks or things that would help me figure out what to do?

Thanks,
Sara

We flash heated 4oz frozen bags at a time (I liked the lansinoh bags best, especially for doing this, as they are thick and strong). Basically, we'd directly transfer a frozen bag of milk into a beaker of boiled water and immerse. This rapidly thaws the milk and probably pasteurizes the outer layer only (since the temp. will rapidly decrease due to the frozen milk. After approx. 2 minutes we would MIX the thawed milk in the bag and transfer to another beaker containing freshly boiled water, and immerse for 5 minutes, MIX and repeat this procedure once again with freshly boiled water (we have an electric kettle, so it makes water boiling very easy). That was it!! We dispensed the now hot milk into a sterile bottle and cooled at room temperature for about 10 minutes before giving to baby.

Typically, this was done about 30 minutes before a scheuled bottled feed, but we also prepared bottles in advance (for trips etc. if I was not there to nurse directly). The bottles could be stored afterward in the fridge, although we never stored thawed milk for longer than 8h approx.

We did also try 'mass' pasteurization firstly, whereby we thawed a larger volume...approx. 20 oz and heated at a lower temperature for 20 minutes (I believe it was 75 degrees C). I was not a fan of this because you had to put the milk into a pan immersed in another pan of water, and try to maintain a constant temperature, which is difficult to acheive and monitor.....you really need professional pasteurization equipment to do this properly. I was not a fan because after you had to re-portion the batched milk into 4oz aliquots and re-freeze for long-term use. I did not like all that extra handling...seemed like the ideal situation to introduce fresh pathogens once the milk was pasteurized!!

The main reason we never repeated this, was that our baby refused the milk that was treated in this way....she just would not drink it for whatever reason.....perhaps the prolonged heating changed the taste. Eventually, she had no problem with the flash boiling method and drank this milk just fine...at the beginning, she was also reluctant to take flash pasteurized milk also, although she did drink it. With the batch method...she point blank refused!!

We had the same perspective about donor milk...that irrespective of how carefully one expresses milk, there is alwyas the possibility of cross-contamination, that OF COURSE IS UNINTENTIONAL by the donors. The only completely sanitary method of feeding breast milk is direct nursing. I personally think quick, flash pasteurization is a prudent and easy option.

Please see my other posts for information about this topic and particularly a powerpoint presentation that debunks some of the commonly touted myths about pasteurization (the link is at the end of one of those posts).