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Enoltech often have them second hand.

Malowicki gives the activation energy for isomerisation as 98 kJ / mol so the isomerisation rate ratio will be given by E^ (Ea/(R.T1)- Ea/(R. T1-10)) For 100 vs 90 oC this is E^ (98000 / 8.3 x 373 - 98000 / 8.3 x 363) which is about 1 / 2.5. Repeating the calculation for 80 degrees gives a...

60 ml of spirit in say 20 litres of beer? That will raise the ABV by about 0.12%: the yeast will hardly notice

Personally, I don't like the smell of myrcene so no.

Citric acid has very limited antioxidant poperties, I would not have thought it functioned as an antioxidant in wort. Did you mean ascorbic acid?

Log Kow for Myrcene is 4.33, so the myrcene in 500 ml of beer would reach equilibrium with ~10 mg of a linear alkane*, eg the total quantity of myrcene would be split equally between the two. Assuming the liner weighs at least a gram, more than 99% of the myrcene would eventually end up in it...

Not so: I routinely put yeast through about 17 generations and that was in grape juice, which is a much poorer growth medium than is wort. To make up enough yeast to pitch 300 kl of grape juice we used a kilo of dried yeast ( ~ 6 * 10^12 cells) and grew it up unitl we had about 8000 l at . 10^8...

Unless your dried fruits are a huge percentage of the total fermentables the yeast will happily cope with the SO2. If you've ever tried to stop an active fermentation by adding SO2 you'll see that you need a shedload of it to make a signifcant difference. Be careful with the rum additions...

Exactly: an additive is defined by its function, not by its mode of action. You are right that usage is a bit broader in wine: I am currently looking at fining trials in my '17 chardonnays and it will make SFA difference to clarity after they are cross flowed through 0.2 micron membranes. What...

SS sucks as a heat transfer medium but in this application it is unlikely to be the rate limiting step. It will be clobbered by flow velocity: if the flow is below the Reynold's number you'll get poor heat transfer as the flow laminae act as insulators. If the flow is above the Reynold's number...

In French, fining is "collage", the word also means "gluing". The basic action is to bind together small particles so that the agglomeration becomes large enough to sediment out. It can be argued that since PVPP is itself large enough to sediment out that its action can be technically described...

In practical terms you can safely ignore the salts in the water supply in Melbourne and just add salts as appropriate for your brew. As a base, I add 1 ml / l of 10% sulphuric acid and 0.2 g/l of CaCl2 to the mash, then 0.1 g/l of each of CaSO4 and CaCl2 plus 0.02 g/l of MgSO4 to the boil. I'd...

Did you not recognise the quote?

Have you measured the exit water temperature and volume from the counterflow chiller? If so we can use them to calculate the chiller effectiveness and answer your question. Without that data we are just guessing, hence the disparate responses.

Yes.

Yes, that's what my equation does. Enthalpy of vaporisation of water is around 2.26 MJ / kg, so the energy required for boiloff = 2.26 MJ/ kg x (Vstart - Vend) (Eq 1) Heat capacity of wort is around 4 kJ / kg / oC, (slightly less than water at 4.18 due to the sugar content), so the energy...

I don't understand your post but to be clear the calculation gives the efficiency according to a standard engineering definition eg work done / energy expended. It should be obvious that the "energy expended" is the heat of combustion of the gas.

Easy version of that calc: Percent efficiency = (4.8 x start vol - 4.52 x finish vol) / mass of gas used. Calculation assumes the wort was heated from 65 oC, that it has a heat capacity about 4 kJ/kg, that the vapour driven off is substantially water and that there is no condensate return.

Actually a combination of etching* and oxidation. The grey is etching, the white spots are oxide. You have probably extracted a fair bit of aluminium into the brew but most of it should come out in the trub; aluminium salts are generally poorly soluble. *An alkaline peroxide etch is one of...

That's not true, you can oxygenate a starter to your heart's content. What you shouldn't do is oxygenate dormant cropped yeast.