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We all know about pH, we knew about it before we started brewing, at the very least through primary school science or gardening or fish tanks or swimming pools and that’s just the tip. Avid gardeners have known for years that many plant’s, hydrangea is the most quoted, flower colour will change according to the acidity or otherwise of the soil, a pH flower meter if you will.
As a brewer you will know that pH is important but how, and this (after Elliot) leads us us to an overwhelming question and well you might ask “what is it?”.

A reference to any text or indeed wikipedia will give an answer some thing like “pH is a measure of the activity of hydrogen ions” which may or more likely not explain everything, it certainly does not explain why pH is important in brewing. Is it about your mash pH, many seem to think it is and I have no argument with them but I suspect that your sparge pH is far more important especially in Canberra where our water is so good. Anyway that is really not what this is about, not at all.

It is about the overwhelming question.
In this case it is quite a simple question: “with regard to pH which is more significant, beer or the pH of beer or wort or sparge water”

It is not even a riddle despite the rather successful attempts by Benedictine monks to make make carbonated wine.
Neither is it a Catch-22 but Soren Sorensen leads us to a decision.

Beer is the answer.

Quite simply Sorensen, working at Carlsberg Labs, the very same labs in which Hansen isolated the Lager strain of yeast, the same labs that Claussen identified the so called British yeast.  It was Soren Sorenson  realising that the acidity of the wort was a major factor in the fermentability and thus the final beer introduced a scale to measure, report and compare. He called this scale pH.

Without beer, or more specifically the science of beer pH which we take granted may never have existed.

Next time you eat a peach imagine the revisions of decisions, the blind men in the alley without the compass of pH and thank your humble beer (or rejoice if you like, you really should)

The more historically correct Newton story is that he was lolling under a tree, eating an apple and drinking a mead when an egg fell from a nest and did dirty him somewhat.
Like all things connected this brings me to the subject of Eggs, Gravity and Mead.
Of course you do not need a hydrometer when making mead, with a known weight of honey and a known volume of added water it is a trivail matter to calculate the starting gravity.
But what happens if you are making mead from cappings or have either an unknown weight or volume and you broke your hydrometer. Well the mead that Newton was drinking under the tree was not made with the aid of a hydrometer but most likely with an egg (though not the one that dirty him somewhat).
Now we all know that if you place a hen’s egg in a bowl of water, if it floats ..its rotten. So first get a fresh egg , it should, in that same bowl of water sink and sit pretty flat.
Place this egg in your honey water mix to establish the gravity, the higher the gravity the higher the egg will float.
At 1085 the top of the egg just touches the surface.
By 1095 it will be 18mm above, 1100 20mm, 1110 25mm and 1120 30mm.
Of course at the end of fermentation the egg is going to sink, unless it was the egg you started with…
This is where the apple comes in.

We are all experts on yeast, it’s what makes beer after all.
Mashematics stock a range of nutrients but the question is: are they required ?
Answer is: No.
Assuming your yeast is viable you really only need chuck it in and let it go. All grain wort has just about everything in the way of nutrients that yeasts needs, you don’t have to add anything, you don’t even need to aerate.
But you can do a lot better, you can help your friend yeast produce a much better, more consistent beer by optimising conditions.
All grain wort contains adequate amounts of everything yeast needs except for Zinc and Oxygen.
Oxygen is an easy one, yeast needs oxygen during its growth stages, the process is complex but essentially for yeast to continue budding it requires sterols, which the yeast can synthesise but not without oxygen. Thus oxygen becomes a limiting factor in fermentation, a well oxygenated wort (8-10ppm) will reach a lower terminal gravity and in a faster time than a less than adequately aerated wort.
Splashing and shaking is certainly a good start but oxygen levels are typically 3ppm at best. Pure oxygen, injected through a sintered stone will oxygenate 20 litres of wort to the 8-10ppm range in about 60 seconds.It would appear that too much oxygen is merely a waste, so 90 or 120 seconds is not deadly.
Zinc is important in reproduction of yeasts and is a co-factor for alcohol dehydrogenase (the enzyme that creates alcohol).
It is important that the zinc is available to the yeast and this can achieved by the use of Servomyces Servomyces Spec Sheet.
If you are using dried yeasts another very important factor is proper rehydration of the dried yeast.
Once again, not rehydrating is not going to hurt, its just giving less than optimal conditions.
First concept reydration is nothing like making a starter.
Temperature, always important in fermentation is critical in yeast rehydration.
In the first few minutes the as yet not properly constituted yeast wall will allow toxins such as hop compounds and even high sugar levels to pass through reducing overall viability so water is a good start anyway.
You need to pitch your dried at about 1:10 (yeast to water) in standard tap water, if you are worried about chlorination then boil and cool.
The temperature will vary according to strain, it could be as low as 30-35C or as high as 42-45C but 40C is just about right, the critical period is less than a minute after pitching which is when the yeast starts reconstituting its cell wall structure, lower temperatures will drastically reduce yeast viability, at 24C you will have 75% viability compared to 40C.
It gets better.
When you are rehydrating your yeast you can further optimise your fermentation by adding agents such as GoFerm Evolution GoFerm Spec .

So, you have oxygenated your wort, if using active dry yeast properly rehydrated with GoFerm for good luck, do you need additional nutrients, clearly NO you do not.
Which is why Mashematics carries a range of nutrients…what you don’t need is often what you miss.

Welcome to Mashematics…I hope you like it.
Mashematics was created in 2009 and continues to serve its primary market, Canberra Brewers.
Feel free to come over and pick up ingredients and gear by appointment.
I generally don’t post but happy to provide a price (cost).
So, have a look around the most extensive range of specialist All Grain brewing stuff in Canberra.