60 min vs 90 min boils

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The Thiobarbituric Acid Index (TBI) is a measurement of thermal stress in wort and malt.

Maillard products formed from amino acids and reducing sugars during wort boiling are detected using this method.

Measuing the increase in TBI during boil is a good indication of thermal stress.

A low level of thermal stress is beneficial for the flavor stability of beer since fewer Strecker aldehydes are formed.

Generally, a TBI of <45 is desired.

Now, here comes the proverbial spanner....

This figure does not apply to the wort used to produce darker beer styles. Copious amounts of maillard products and Strecker aldehydes are purposely formed in the malt, since they are desirable in the aroma profiles of these beers.

So it depends what you are aiming for. I would not discount the importance and the effect of a carefully conducted boil.

Never mind the effects on free DMS and DMS-P, as well as coagulable nitrogen....
 
If you're wanting flavours from maillard reactions, why not just use a bit of more-roasted malt in your grist? That way, the maillarding (new word!) is done for you by the maltster.

Actually, Maillard reactions take place at any temperature, but they go fastest at these temperatures.
Good to know, thanks athumb..
 
If you're wanting flavours from maillard reactions, why not just use a bit of more-roasted malt in your grist? That way, the maillarding (new word!) is done for you by the maltster.


Good to know, thanks athumb..
A fair point, but a) how much of which dark malt do you use to correct a recipe to account for a shorter boil (trying to do exactly that with Munich malt to avoid a multiple-decoction mash in Czech lagers is a nightmare in itself) and b) Maillard reactions was only one of the factors to consider.
 
If you're wanting flavours from maillard reactions, why not just use a bit of more-roasted malt in your grist? That way, the maillarding (new word!) is done for you by the maltster.


Good to know, thanks athumb..
Perhaps things taste differently.

Why grill a steak when you can just coat it in burnt bread crumbs from the bottom of your toaster?
 
"Wort Boiling and Maillard reactions: Wort contains high levels of reducing sugars and enough amino components which can continue to participate in Maillard reactions during wort boiling. Maltose and maltotriose are the most abundant sugar compounds in wort and thus, these sugars and oligosaccharides form their own specific compounds induced by Maillard reaction chemistry."

https://www.brewersjournal.ca/2017/05/18/science-malliard-reaction/
 
You missed of the next sentence in your quote.

"One main flavor compound generated by the Maillard reaction found in wort is furfural. This compound has frequently been regarded as an indicator for heat damage of wort"

This document also contains the Quote about taking days when under 100 deg C & hours Over 100 deg C.

buddsy
Trap fallen in to.

How can furfural be created if, as you say, the wort isn't getting hot enough for long enough, for maillard reactions to occur?

Again, you are missing the point that wort isn't at 100°C at the heating interface.
 
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haha wort making is so much deeper than my mash tun.

From my very limited understanding of the whole process Im amazed I am able to even produce drinkable beer!

buddsy
Always take the historical context into account. People have brewed for at least 7000 years, scientific brewing (using thermometer and hydrometer) is around 250 yrs old, and the chemical and biological knowledge around 150 yrs. If it hadn't tasted well in the years before, surely humanity would have stopped brewing?

  • Work clean
  • Get your temperatures right
And the duration of the boil: you should have a look at recipes on "Shut up about Barclay-Perkins", boil times from 90 to 240 minutes for old recipes...
 
It might be worthwhile taking notes of various boil schedules and then compare results. A good approach would be if that's the only variable. One has to dial in a suitable schedule for oneself. Shame that most brewing software, even commerical, ignore boil schedules. But then, one can always record this in the notes.

It helps to have an idea of what is going on, but it is not essential.
 
Science proceeds by hypothesis, experiment and explanation. David Heath and others have hypothesised that 30 minute boils work for modern brews and have claimed to have tested this. 2 months ago I performed a 30 minute boil experiment with two of my standard beers, an APA and a German style Lager. Colour was fine, clean up was easier as my braumeister heat coil had less burnt crud on it, FG was normal, volume was slightly up (less boil off).

These are beers I have made many times per year for 15 years or more, so I know what to expect. I can say that to my palate I cannot taste any difference. No off flavours, mouth feel is full, as usual, even on the lager. I will keep experimenting with other styles, but for these styles, ingredients and equipment it seems to make no difference.

Not being a food scientist I don't attempt to explain why it works.
 
Another thread that descends into the depths of one man trying to outdo the other with superior knowledge.
RIP 60v90.

I'd probably view it that way if I wasn't intelligent enough to realise that arguing and debate is the principle driver in knowledge acquisition. Debate is pretty much fundamental in learning and science. Present your point with evidence for others to critique and respond to. And why all good scientific papers end with both discussion and a conclusion. The world used to be flat, until someone argued it wasn't. I wasn't involved in that one, yet feel better informed by the correct outcome.

You'd think multiple participants would indicate that the exchanges were relevant to the topic. Evidently not. Although, it's ironic that you're own interjection has added nothing to the answer the original question.
 
I think we are having a good debate. All points have been valid. I respect David Heath and appreciate philthebrewers findings. I checked my Gordon Strong book and he's on the 60/90 minute side. I'm going to give 30 mins boil on my next brew and see how it goes.

Buddsy
 

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