Tesco Ashbeck water - why is it not ideal?

Doram

[Hi @Rob1 - I am copying your quote below to a new thread here, because I think it deserves its own place and didn’t want to divert the “Lelit reliability” thread where I found it:]

Rob1 Ashbeck isn’t ideal… Better off just getting a zero water jug and remineralising with bicarb.

When you say Ashbeck isn’t ideal, what exactly do you mean (for espresso)? Is it because it will scale? Or because the coffee won’t taste great? Or because it’s bad for the environment? Or something else?

I think that people are drawn to Ashbeck because it’s an easy solution for their machines. Having to remineralise RO or Zero water is a barrier for some. We might do it in the future, but not ready to make the leap just yet. I am personally in that camp, so looking for an easy “ready made” solution that I don’t have to think too much about. I understand Ashbeck is a compromise (what isn’t?), but what I don’t know is what sort of compromise it is.

What I am interested to know isn’t the chemical formulation that is beyond my understanding (too much X, not enough Y, low PH etc.), but rather the effect it has (e.g. - the machine will scale and might need descaling once a year; or - the coffee will taste X or will miss Y because the balance of mineral is too Z; or - the boiler might corrode, etc.). I Would really appreciate it if this is something you could explain for those of us who find the water issue too complicated and overwhelming.

Finally, is there a better, easy, ready made compromise, that will not cost a fortune, doesn’t take up counter space and electricity, will not involve remineralisation and will not kill a machine too quickly, providing we are willing to accept it’s a compromise on taste? (I am asking a lot, I know, lol).

If we do go for a Zero water jug + bicarb as you suggested above, what will be gained compared to Ashbeck (in terms of scaling and taste?).

Sorry if this is asking too much and thank you for all the insights and for sharing your vast knowledge!

MediumRoastSteam

Doram Having to remineralise RO or Zero water is a barrier for some. We might do it in the future, but not ready to make the leap just yet.

Don’t let this be an issue. It’s a very simple thing to do, honestly. Takes seconds!

Doram If we do go for a Zero water jug + bicarb as you suggested above

This is a question I’m asking myself. I’m very keen on the Skuma. It does RO water, remineralises on the fly with a concentrate you could even make yourself, dispenses hot water, the filter lasts 1 year, and is able to output in excess of 450L with moderate hard water (that’s less than 300ppm) going up to 700L with less hard water, at a cost of £35. Those are claims made in the Skuma thread. The price is also very competitive.

As much as I’d like one, I’m somewhat skeptical as I haven’t seen anyone rather than Skuma themselves talk about the device. So, to me, it’s not yet proven or tested. But if it works as claimed on the long run, it’s really cost effective. Compare that to Zero water, where two cartridges cost approx. £15 each would produce approx. 60L of water and would need to be replaced once a month. I know someone here said they keep theirs for 3 months, against manufacturer recommendation and it’s been fine. It we know what the Zero water delivers as it’s been out there for a while.

MWJB

Doram When you say Ashbeck isn’t ideal, what exactly do you mean (for espresso)? Is it because it will scale? Or because the coffee won’t taste great? Or because it’s bad for the environment? Or something else?

I think that people are drawn to Ashbeck because it’s an easy solution for their machines. Having to remineralise RO or Zero water is a barrier for some.

Ashbeck is low in alkalinity and pH, it errs towards corrosive. I don’t like the taste of coffee brewed with it, but others might. At the end of the day boiler water recommendations are not specifically focused on taste, you can still make bad cups with any water, you might even like the taste of less than ideal water. They’re aimed at protecting your boilers.

You could buy an RO system that produces water with higher alkalinity than Ashbeck, so the idea that you only have to remineralise RO, or Zero jug water is a fallacy.

Ashbeck is easy, sure, but it’s not a solution.

The boiler recommendations are essentially very simple, aim for an alkalinity of 40-60mg/L as CaCO3 (Ashbeck is about 20mg/L). Bottled water options are Waitrose Essentials Lockhills, Speyside Glenlivet (not easy to find these days, though again I didn’t like the taste)…Volvic & Acqua Panna are 2nd tier bottled water choices (high in alkalinity/bicarbonate).

The first step to working out what you need to do is to check the in depth water analysis based on your postcode, with your water supplier, hardness will be easy to find, but you also want to know alkalinity/bicarbonate/temporary hardness (most critical).

Rob1

Doram When you say Ashbeck isn’t ideal, what exactly do you mean (for espresso)? Is it because it will scale?

MWJB has already explained a number of things….People generally use and recommend Ashbeck on the basis that it “doesn’t scale”. So, additionally, I’ll say it will cause scale quite quickly in a service boiler unless you’re going to throw some away as a sacrifice every time you use steam (just to delay the process of draining the boiler completely) and the quite high presence of chlorides is something I’d avoid, especially in light of this. Ideally, chloride and sulphate will be within a certain ratio for taste (apparently) and there are additional corrosion concerns if they are present. I just avoid having either present in the water entirely…..though that’s going to be very difficult with any type of bottle or filtered tap water, so you’ll probably be pulling your hair out using anything other than distilled if you try to address this.

Doram Now to the more complicated issue of taste: Ashebeck is too low on alkalinity and pH. But how does that translate into taste in ways that I can understand, without going into numbers or being overwhelming? Can anyone, for example, share their experience of how espresso taste changed for them after moving from Ashbeck to, say, Osmio Zero?

Alkalinity is the buffer to acidity. So how it affects taste is coffee-dependent and your appreciation of it is subjective. Nobody can really say if you’ll like the taste of any given coffee brewed with water that’s quite low in alkalinity.

How this transaltes is increased risk of corrosion, and coffee that tastes more acidic - all other things being equal compared to higher alkalinity and pH.

Doram First, I think we need to separate ‘bad water’ into two things: scaling and taste. I think many of us know what scaling can cause - we have recently seen an example of that with an ECM machine (I think it was @CardinalBiggles ', but I can’t find the thread just now). I know my tap water is hard (~230 TDS on a simple electronic meter + info from supplier). Ashbeck is about 80 on my TDS meter, so although it might also scale - is a big improvement over my tap water in the scaling department.

The TDS meter isn’t going to tell you if the water will scale or not - the Ashbeck won’t scale as in ordinary boiler temps and probably not even in the Elizabeth boiler that (IIRC) can run around 160c, so I don’t know why you think it might scale based on the TDS reading. Scaling is determined by the balance between carbonate alkalinity and temporary hardness at a given temperature.

Dusk I just wonder whether there is an easy way for idiots like me to know what water is best if I were looking at a couple of different bottles in a supermarket?

Download my spreadsheet to your phone. As MWJB said above, the options are limited but I’ve seen some foreign labels posted so….

Look at the label and put the bicarbonate, magnesium and calcium values into the sheet.
Put your max operating temp in there (i.e max service boiler temp you use) and it’ll give you a “max hardness before scaling” calculation…
Compare this to the hardness automatically calculated from the calcium and magnesium entries and decide if you’re going to use the water or not.

You may decide to just put your brew boiler temp in and live with descaling the service boiler only….I’ll probably edit the sheet one day to make it a bit clearer.

Generally, avoid high chloride and sulphate values and aim for between 40-60mg/l alkalinity - you may prefer the higher end or lower end. Max hardness without scaling varies based on temp and alkalinity but look for less than 30mg/l (40mg/l might be ok). The issue is the labels don’t always give hardness and alkalinity as CaCO3 hence the need to calculate.

CoyoteOldMan

MediumRoastSteam Zero water, where two cartridges cost approx. £15 each would produce approx. 60L of water and would need to be replaced once a month.

I’ve been through all the Zero Water UK site, and I can’t find a recommendation to change the filter once a month. There is this:

whether that’s credible is a different story, but mine has been running for six weeks and there is absolutely no smell or colour to the water/filter. The NSF certification gives 45 (US) gallons (i.e. 170 litres) as expected life of a filter element, but the certification is based on heavy metals and dissolved gases removal (which is likely to happen in the ‘carbon’ part of the filter), not softening/ion removal.

Zero say that the ion-stripping resin is sufficient for 18,000 mg of ion removal, which would make that part of the filter last 170 litres with ~100 mg/l of ionic content (moderately soft water).

My unfiltered supply is between 300 and 400 (Thames Water values), so I fully expect to replace the filter every 30-40 litres. At current rates of use, that means every 2-3 months (espresso and Turkish only; happy to continue with my inline filter and softener for other purposes - we don’t drink much tea, either). My running cost is very low…and the cost per cartridge goes down even further if one buys packs of 4 - or 8.

I’m posting this as a different use case - just saying that an RO system is not necessarily the cheapest for everyone.

Alpesh

I too find this topic a little overwhelming and would appreciate the pros and cons laid out in layman’s terms.

I have been using a mix of 50:50 Ashbeck and Volvic and understand that I will need a light descale one every 1-2 years based on my usage.

Ideally I would go the RO route like many of the experts on this forum seem to have and have been looking at both Skuma and Osmio Zero with interest but countertop space and initial outlay is a factor.

The alternative I have been considering is the Zero water jug and remineralisation if that offers better protection for the coffee machine (less frequent descale) and better taste as compared to Ashbeck+Volvic.

With each of these options and the benefits laid out would help someone like me pick what is right for them with the understanding of the consequences.

Perhaps it is not as simple as that given the detailed discussions I have seen on the subject of water.

MediumRoastSteam

Alpesh and better taste as compared to Ashbeck+Volvic.

Same here. I’ve been using distilled water for over two years now, exclusively for coffee brewing. The process is inefficient, taking 6 hours to produce 3.5L of water and working out a similar cost to bottled Ashbeck, per litre. However, it doesn’t waste plastic nor water and you could argue it’s “green” providing your electricity comes from renewable sources.

But I asked a question in the Skuma thread, asking whether distilled water tastes the same as pure RO water and the answer was No. now, let me tell you, distilled water tastes, errr…. Of nothing apparently, and what you taste is the actual taste of your mouth. Some say it tastes plasticky. It tastes diabolical in tea or in an Americano, making a very flat beverage. It seems so be OK for espresso.

So I’m curious to try RO or Zero water, and, technically, on paper, the cost of running the Zero Water would be the same as the cost of running the distiller.

I’ve been trying to convince the wife whether we could welcome the Skuma to our home. She said she likes the idea of having filtered hot water on demand, but unfortunately our counter space is at a premium.

The plot thickens.

On Ashbeck, I heard some say it can corrode the boiler on the wrong run. I never saw evidence of this. It also has a significant amount of chlorides which is not good in a service boiler environment, apparently.

LMSC

MediumRoastSteam counter space is at a premium

Utility room?

MediumRoastSteam

LMSC our house has a utility room, but it’s a converted garage. Although it’s attached to the house, one needs to physically leave the house through the back door first. I don’t see the other members of the household doing that when the kitchen tap is more accessible.

LMSC

MediumRoastSteam That’s a shame! Are you not able to squeeze a small side table or install a small cabinet or an open shelf above the kitchen worktop to release some space? I am sure you would have done that, if possible.

LMSC

MWJB You could buy an RO system that produces water with higher alkalinity than Ashbeck, so the idea that you only have to remineralise RO, or Zero jug water is a fallacy.

The Ozmio Zero’s alkalinity from its’ pure RO water in our case is typically around 15-20 mg/l. It has a remineralisation filter. The resulting alkalinity is typically around 40–50 mg/l. This is perfect for our boilers. The filter is changed once a year as the unit gets the softened water.

The Ashbeck bicarbonate is 25 mg/l. I suppose one will have to prepare a concentrate or add 125 mg/l to a 5L bottle and use that? It is going to be hard weighing up 125 mg even with a jewellery scale ?

https://www.tesco.com/groceries/en-GB/products/301227531

The Waitrose lockhills bicarbonate is about 60 mg/l.

Doram

MWJB The boiler recommendations are essentially very simple, aim for an alkalinity of 40-60mg/L as CaCO3 (Ashbeck is about 20mg/L).

LMSC The Ashbeck bicarbonate is 25 mg/l. I suppose one will have to prepare a concentrate or add 125 mg/l to a 5L bottle and use that? It is going to be hard weighing up 125 mg even with a jewellery scale ?

MWJB You could add 200mg/l of sodium bicarbonate to 5l of Ashbeck, 0.01g scales will be fine, I use these anyway for fast dosing of coffee. (40mg/l of sodium bicarbonate will result in an additional 24mg/l of alkalinity)

When starting this thread, I was hoping to make this one a little different from the many other water discussions that I have read. I quoted some examples above to illustrate the point: we easily move to discussing numbers (alkalinity is XXX but ideally needs to be YYY, so lets add ZZZ etc.). This keeps going back to “you need a to get X water (Osmio Zero or other RO or pure water), and re-mineralise it with Y to make it ideal”.

However, what I am curious to know is what effect does using the ‘wrong’ water (e.g. water with not enough alkalinity, or with too low pH, such as Ashbeck) have on espresso? Will the coffee taste flat/bitter/sour/dull/weak/something else?

First, I think we need to separate ‘bad water’ into two things: scaling and taste. I think many of us know what scaling can cause - we have recently seen an example of that with an ECM machine (I think it was @CardinalBiggles ', but I can’t find the thread just now). I know my tap water is hard (~230 TDS on a simple electronic meter + info from supplier). Ashbeck is about 80 on my TDS meter, so although it might also scale - is a big improvement over my tap water in the scaling department.

Now to the more complicated issue of taste: Ashebeck is too low on alkalinity and pH. But how does that translate into taste in ways that I can understand, without going into numbers or being overwhelming? Can anyone, for example, share their experience of how espresso taste changed for them after moving from Ashbeck to, say, Osmio Zero?

MWJB

LMSC The Ashbeck bicarbonate is 25 mg/l. I suppose one will have to prepare a concentrate or add 125 mg/l to a 5L bottle and use that? It is going to be hard weighing up 125 mg even with a jewellery scale ?

You could add 200mg/l of sodium bicarbonate to 5l of Ashbeck, 0.01g scales will be fine, I use these anyway for fast dosing of coffee. (40mg/l of sodium bicarbonate will result in an additional 24mg/l of alkalinity)

You could also add a proportion of your tap water to Ashbeck/Zero jug water to get the alkalinity in range. This is quickly & easily done with kitchen scales & easy to adjust from brew to brew/batch to batch.

CoyoteOldMan I’ve been through all the Zero Water UK site, and I can’t find a recommendation to change the filter once a month. There is this:

European guidance for water jug filter changes is 2 months, at nearly 300ppm hardness I would get 4 months to a Zero cartridge at around a litre per day, before the TDS meter read 006 or more. I only used the water for hot drinks.

dutchy101

CoyoteOldMan My unfiltered supply is between 300 and 400 (Thames Water values), so I fully expect to replace the filter every 30-40 litres.

This is consistent with my usage. A filter lasts me 35 litres on average. If you are using the Zero for drinking water, that would get very expensive, very quickly, but to feed a machine only, it’s not too bad at all

dutchy101

CoyoteOldMan My unfiltered supply is between 300 and 400 (Thames Water values), so I fully expect to replace the filter every 30-40 litres.

LMSC

…

LMSC

MWJB You could add 200mg/l of sodium bicarbonate to 5l of Ashbeck, 0.01g scales will be fine, I use these anyway for fast dosing of coffee. (40mg/l of sodium bicarbonate will result in an additional 24mg/l of alkalinity)

Oh yes ! We need additional 125 mg/l of bicarbonate to 5L of water .😊

MWJB

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MWJB

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Dusk

Is there such thing as an ideal set of values for water for espresso machines? Or are there too many variables that can make a difference depending on their relative ratio’s?

I just wonder whether there is an easy way for idiots like me to know what water is best if I were looking at a couple of different bottles in a supermarket?

CoyoteOldMan

Dusk I’ll attempt an answer (from “idiot” to “idiot”)…

TLDR answers to your questions in order: no; yes; no.

All the research/guidelines I have seen (or seen summarised) point to the fact that there is a relatively broad range of acceptable values even in terms of ‘summary’ parameters (overall hardness and alkalinity); more so if one starts considering other factors (e.g. corrosiveness of sulphates, chlorides, hydroxides, potential biological effects of organic ions like citrate, solubility and safety of various salts vs. use convenience, protection from corrosion because of passivation deposits, …).

On the other hand, there is a set of imponderable/subjective/personal preferences on taste. I have experimented recently (and only on Turkish brew) with four water recipes back-to-back: carbon filtered, “hard” tap water (GH =294 and KH = 236 as per Thames Water report); de-ionised not remineralised; de-ionised remineralised with KHCO₃ and MgSO₄ (GH = 60, KH = 40); de-ionised remineralised with MgSO₄ and Ca citrate (GH = 70, KH = 50). There are easily visible differences in e.g. how much foaming the coffee produces, and there are also easily perceivable differences in taste. The best tasting for me is the Mg + KHCO₃ recipe - but that’s obviously subjective, and the preference may well change if I changed coffee or brewing method.

There is also another type of subjective preference: how much is one ready to accept in terms of scaling and/or corrosion in the name of better taste… or the hope of it. That in turn introduces even more variables in terms of materials (copper, steel (which steel?), brass, aluminium, platings, linings), technology/machine design and brewing preferences.

What water to choose at the supermarket - very simplistically, one that has a low amount of dissolved minerals, particularly Ca and Mg (as those are the main culprits for causing scale). A low mineralisation water may not have sufficient alkalinity, although that is easily corrected by adding a little bicarbonate (as per the thread above) - however, KH is seldom indicated on the label of bottled waters, so one is left guessing - or buying a KH kit. Then, coffee made from a low mineralisation water may not have the best taste (subjectively…), so one ends up adding Mg or Ca. But that is more likely to cause scale, especially if one has used bicarbonate to add alkalinity. Never ending circle of despair.

Or pick up a bottle of de-ionised water, use Dr. Pavlis’s recipe (50 mg NaHCO₃/l) and be done with it. Ingredients are cheap and available in pretty much any supermarket. It won’t scale, and by many accounts it tastes pretty nice when making espresso.

MWJB

Dusk I just wonder whether there is an easy way for idiots like me to know what water is best if I were looking at a couple of different bottles in a supermarket?

Look for water with a pH of 6.5 or higher and 50-75mg/l bicarbonate. There are only 2 or 3 options discussed above.

Be aware that bottled water is essentially just water in bottles, as with tap water, it is massively varied in make up and the vast majority of it is just as unsuitable for your boiler.

Dusk

MWJB

Doram This keeps going back to “you need a to get X water (Osmio Zero or other RO or pure water), and re-mineralise it with Y to make it ideal”.

No it doesn’t. I suggested you find out what water you receive at your tap. When we know this we can suggest a course of action (sure, it might end up as low TDS/TH/alkalinity water & remineralisation, but there might be other options too).

Remineralisation can be achieved in several ways, including adding some higher mineral tap water to purer water.

The numbers are how we determine the suitability of boiler water, because boilers don’t have a sense of taste, they scale, or corrode. This is why discussions on this topic will always end the same way.

If you are using Ashbeck and you are happy with the taste, try adding sodium bicarbonate and see if you are still happy. I’m not saying you have to do this, it’s a free country, but you asked why it wasn’t ideal and this is a straightforward adjustment.

I found that Ashbeck made my brewed coffee a little dry, like black tea with no milk (not something I enjoy, I know others that do), but also a little sour (compared to other waters at the same brew regime and with the same coffee, Lockhills wasn’t available back then but I’ve not had any issues with it in the meantime).

Low akalinity water tends to generally make coffee brighter/more sour (even at an extraction that otherwise wouldn’t be), sometimes a perception of it being thinner.

TDS is not a good guide to alkalinity.

LMSC

Doram what effect does using the ‘wrong’ water (e.g. water with not enough alkalinity, or with too low pH, such as Ashbeck) have on espresso? Will the coffee taste flat/bitter/sour/dull/weak/something else?

Effect and taste are relative to our taste buds .

Doram Ashebeck is too low on alkalinity and pH. But how does that translate into taste in ways that I can understand,

I think the taste difference, which I think is brightness or acidity and mouthfeel between a cup with a lower alkalinity and the cup with the ideal level will not be significantly different that we can’t drink it. But the cup with the lower level of alkalinity would be brighter, more acidic and sharper mouth feel (texture).

I could be wrong and am happy to be corrected with the correct interpretation.

CoyoteOldMan

Doram I can’t tell you the difference from Ashbeck to Osmio, but my experimentation led to the following ‘tasting notes’. The water recipes I used were:

Carbon-filtered tap water (otherwise it smells/tastes of chlorine!). GH = 294, KH = 236 per 2021 Thames Water report; probably a little less after the carbon/ceramic filtering.
Straight de-ionised water from a Zero Water jug (TDS = 1 - presumably GH ~0 and KH ~0)
De-ionised + MgSO₄ / KHCO₃ - GH = 60, KH = 40 (from a concentrate)
De-ionised + MgSO₄ / Ca citrate - GH = 70, KH = 50 (from a concentrate)

Taste:

Foams much more than all the others (it was evident!) - grittier texture. Fairly sweet, chocolate note prominent.
Very clean texturally. Less sweet than others; a bit of a sour aftertaste.
Very sweet. No bitterness at all. Chocolate and hazelnut. Nice texture.
Slightly smoky/bitter (burnt caramel?) at the very end. Clear vanilla-like note at the very beginning. Best texture - silky and smooth, but with some body.

Not a world of difference, but clearly perceivable. All 4 cups were nice and drinkable, but we both prefer the Mg + bicarb one. Neither of us is a super-taster or a gourmet.

The coffee I used is Saka Gran Bar (fairly dark roast, 10% Robusta - not a delicate flowery thing, but a classic Southern Italian espresso mix), brewed Turkish-style, 12 g of coffee, 120 g of water, infusion from 20 to 90 °C in ~4 minutes, then pour, settle and taste. All coffee was ground in one go, mixed with a chopstick, and divided into 4 equal, weighed portions. I prepared the 4 water solutions, asked my wife to label and mix them, then made 8 coffees (6 in identical cups, plus another pair of slightly different ones), in labelled cups and asked my wife to taste and take notes, but not share them. She changed the labels for ‘my’ cups (and noted how!), and I tasted, we then compared notes. Our impressions were nearly identical. We only did this once, so it has no pretense of being in any way scientific, but the ‘tasting notes’ have been fairly consistent with what we observed when “knowing” what the water was (when not blind making/tasting).

Based on this, I would say that there is a fair amount of sensitivity to even relatively small changes in water composition if one is tasting with attention. A bit like listening to audio systems…