I have a replacement pressure fitting for my espresso machine. It is a small, ordinary looking thing made out of stainless steel, with two threaded ends, a central channel 1/8" channel bored through the long axis, and two copper crush washers.
I ordered it online - it is a fairly generic part that I’m sure is used in all kinds of industries. It is marked “SEALEXCEL 316 SS” - Sealexcel is apparently an Indian manufacturer of pressure fittings.
I assume this part has not been manufactured specifically for contact with food. It looks clean and shiny but seemed to have a little coating of something on the outside, perhaps machine oil to protect it from corrosion in transit, or some kind of light lubricant for the threads? The inner channel is too narrow for me to tell if it is clean or not.
This is a fitting that attaches the thermometer to my espresso machine, so it will be in contact with the water that goes into my espresso.
What can I do to clean this before installing it in the machine? I do not want to be super paranoid about this, but I’d prefer not to ingest machining debris / oils / etc. if I can avoid it. I can wipe the outside, but it is kind of hard to clean the threads and impossible to wipe the interior of the channel. Any kind of solvent I can use that would be food-safe and clean any likely machine contamination?
Most machined parts have a residue of cutting fluid on them. Just clean it in warm, soapy water to remove this film. I doubt it’s even remotely dangerous, but leaving it on might make your espresso taste funny…
If just plain old soap and water doesn’t work, Simple Green usually works pretty good for oil and will rinse off clean afterwards.
Of course depending on what kind of espresso machine you’ve got, it may have a heat exchanger and so the fitting wouldn’t actually be touching the water that goes into your espresso, just the steam that comes out of the wand which I imagine would be even less likely to be noticeable.
Like the others said, soap and water should be fine and it’s probably just cutting fluid residue. I find that a cheap ultrasonic bath works great for cleaning small parts with fine detail. Overkill for a one-shot item but if you anticipate cleaning more small fittings it might be worth it.
Please don’t.
Yes, stainless is a good material for direct contact, but cutting fluids in general should not be ingested.
Yes, you do. You really do.
No, don’t doubt it, please.
The OP has not been provided with a validated cleaning procedure; we have no idea what s/he should do. I would recommend wiping down with rubbing alcohol or vodka, then rinse in dish soap in warm, not hot, water five times, then running it through the dishwasher on light cycle three times.
Yeah, and even though the little tube fittings aren’t necessarily made for food equipment, you can bet a goodly portion of what they’re used for involves potable water of some sort. Whatever they’re coated with definitely isn’t going to be toxic, although could introduce some funny tastes or odors.
I would add that if you are concerned about the stuff, do wash it before you install it instead of just counting on being able to run water through the machine. Again, if this is an exchanger-type* it can be very hard to thoroughly flush the main boiler because all you can really do (without taking it apart) is run steam out and let the boiler refill itself, which isn’t going to flush it out very fast and the contaminants may not even flush out with the steam at all.
*sometimes called “dual-boiler” although that’s a bit of a misnomer.
No, informed. I used to test cutting fluids for carcinogens.
A lot of people tend to assume that, “if it were dangerous, they couldn’t sell or use it.” This is not true.
I’d use alcohol because it’s good on organic solvents (i.e. oily stuff), a chemical engineer told me ten rinse with the right class of solvent removes just about everything, and I think dishwashers to a better job rinsing than hand washing.
(And all this cleaning would take less time than writing my two posts, excluding the actual time in the dishwasher.)
Thank you for the advice, all. I think I will go for the rubbing alcohol and dish soap. I also have espresso machine cleaner used for back flushing, etc. that I will use, rather than the dishwasher.
But, another question came up while I was looking more closely at the parts. The internal threads seem to have a coating on them, sort of a light whitish yellow in color. Any idea what this might be? I assume it is some kind of anti-galling/anti-seize coating, and I was unable to remove it by washing, but I am concerned that pieces of it may flake off as the threads are tightened.
I’ve emailed the manufacturer, but who knows if they will respond.
When attaching threaded plumbing fixtures, like a showerhead for example you’re supposed to wrap the threads with teflon tape, to make a water-tight seal. I’d guess the coating serves the same function.
I can’t quite tell from the picture, but does the coating go all the way back onto the flat inside surface of the fitting? And does the temperature probe go through the fitting? In addition to what ZenBeam said with the teflon on the threads, the material may also act as a gasket preventing steam leaks out the center hole. You should definitely leave that coating intact and even be careful not to damage it. If a little bit of it falls into the boiler that shouldn’t be a problem at all.
(As background, I used to fix commercial espresso machines (among other things) and we would use off-the-shelf pipe fittings all the time without any special cleaning procedure. As far as I know we never caused any mass-poisonings. If I were you I’d quit worrying about it.)
Yes, the coating covers the entire interior. It is hard to see in the photo, but it is not a soft coating at all - it looks dry and crusty, like it was applied as a paste, smeared on the threads and then baked on.
I suppose I am a bit paranoid. I couldn’t care less about germs, but I don’t want to accidentally ingest heavy metals or something else toxic that some engineer in India chose as the cheapest anti-seize coating he could find…
I have a heat exchanger machine - this thermometer attaches to the E61 grouphead (though the channel just above the “mushroom”) to allow a direct read of the brew temperature. So, it is pretty much right in the path of the brew water.
As a point of note, I’d have been more worried if it were a brass fitting. Brass alloys can contain lead to increase machinability (stainless steel generally does not).