Refractometer Liquid Paraffin Calibration

[itma]

A large supplier (Thornes) says...
An aid to calibration. Using medicinal liquid paraffin smear a small amount on the prism. This should calibrate to 24.5% on the water scale. Once the refractomter is set/adjusted to this figure all honey samples will also show the correct water content.
Haven't got one yet but this is the only readily available thing I have seen suggested.

Ray

I think it is worth giving this its own thread (previously the discussion arose following odd advice to use Golden Syrup).


Basically - Liquid Paraffin works.

Having tried a couple of times (fitfully and fruitlessly) to source some "Liquid Paraffin BP" (the 'BP' signifying it as a pharmaceutical standard product), I took the suggestion of a pharmacist and invested £2.58 in a bottle of "Care +" branded Liquid Paraffin. He claimed that it would be BP-grade product, but 'branded' rather than being sold as a mere generic product.

My refractometer doesn't have the very sharpest of blue/white transitions, but with the Liquid Paraffin the fuzzy line spreads between 24.5 and 24.75%.
So I can either read from the white edge of the fuzziness and deduct a quarter of a percent, or read from the back edge (where the dark blue begins) with no adjustment.
Or I could get out the jeweller's screwdriver and tweak it a tiny bit.


Anyway, as at the very least a "sanity check" on your current setting, I have no hesitation in suggesting a fresh bottle of Care+ Liquid Paraffin as a quite readily available* standardised calibration fluid.

* The helpful pharmacist had to order it in. It arrived later the same day (its how they get real medicines), with no additional charge, just £2.58 for the 150ml bottle - about 150x more than you'll need!

 

[Anduril]

I have used liquid paraffin BP. The question asked have you used this before sir. (For temporary relief of constipation). My answer. No I use it to calibrate equipment. The expression on their faces was worth buying it.

 

[jenkinsbrynmair]

veterinary suppliers are a good bet - got mine from fleabay

 

[itma]

veterinary suppliers are a good bet - got mine from fleabay

But I thought

1/ that the stuff you got didn't bring you any relief

Just tried it with medicinal quality liquid paraffin - completely off the scale!!!

and 2/ that you had had to buy 8 quid's worth …

Just ordered half a litre of medicinal grade liquid paraffin off fleabay (on the recommendation of some on here) cost me about eight quid and will last years with plenty spare for the odd stubborn motion
…

 

[jenkinsbrynmair]

you can probably get some elsewhere - just though the veterinary supplies was a good lead as it doesn't seem that popular for human treatment any more.

GAve me a BIX reading of 68

 

[itma]

you can probably get some elsewhere - just though the veterinary supplies was a good lead as it doesn't seem that popular for human treatment any more.

GAve me a BIX reading of 68

Ummm, but 68 Brix is something like 30+% water … which ain't what it should read.

… which could be explained by any combination of the following -

-- vet stuff is diluted
-- your eBay dealer is cutting it before selling it on
-- or your refractometer is waaaay off


Emyr, if you PM me an address and I can find a suitable tiny container for postage, I'm happy to send you some of the stuff I have, for comparison.

 

[jenkinsbrynmair]

The one thing I do know is that my refractometer is not way off (unless my bees have been reducing the water content of the honey down to about 11%!!)
Thanks for the offer - I've PM'd you

 

[Karol]

Paraffin Liquid BP isn't normally recommended these days for constipation because of the risk of developing lipid pneumonia and because there are better things available.

Although liquid paraffin isn't especially hygroscopic if you have a bottle which has been hanging around quite a while and you've been dipping into it reasonably regularly without religiously sealing the bottle instantly that you've taken your aliquot then you may find the water content goes up over time especially if you're working in relatively humid conditions. Might be worth replacing the bottle once every three years.

 

[itma]

Paraffin Liquid BP isn't normally recommended these days for constipation because of the risk of developing lipid pneumonia and because there are better things available.
…

Which is the reason I was told that it was not kept in stock.
BUT, it can be obtained, on request, very cheaply. You've just got to ask.

 

[Karol]

There's no problem getting hold of it. It's still used for lots of other applications it's just reading some of the other posts on this thread I thought it might be a good idea to advise against anyone thinking of taking it orally.