Topic: Best way to clean??

[Anne]

Hmmm thanks all. I was puzzled by the idea of acid as this glass is regularly used for orange juice but that's not had any impact on the bloom. It's certainly not limescale as our water is very soft so that's never a problem here. This was cartoned pineapple juice not fresh.  I'll go experiment some more.

[Carolyn Preston]

As a point of interest, pineapple juice is far from acidic....in fact in can be almost alkaline.  Hence it is recommended for patients with arthritis......in adition, it contains the enzyme bromelain, an effective anti inflamatory agent, which redices pain and increases mobility in arthritis Patients.  Only fresh pineapple contains bromelain, as it is destroyed in the heat process of packaged juice or tinned pineapple.......so it is a mystery why it would have removed the bloom from your glass Anne.

Another fine reason for one of my favourite fruits! Shame about the packaged/tinned bit. But I will persevere incase there is a bit left  :cheers:  :24:

Carolyn

[Ohio]

Rosie with all due respect Pineapple juice is acidic not alkaline as it rate on the PH charts from a 3.3 to 3.6 canned to 4.0 to 4.82 diluted & since neutral PH is 7.0 anything less than 7.0 is acidic.  For bromelain (the main proteolytic enzyme in pineapple), its optimum pH range, untreated is in the range of 3.5-4.0. I use plain, simple canned pineapple juice & most brands  do contain bromelain, not as much as fresh pineapple but if the bromelain were completely removed in the manufacturing process (and I've found no evidence that indicates bromelain is removed in the general manufacturing process) then it certainly could not be labeled & sold as pineapple juice. Ken

[Lustrousstone]

Pineapple juice may be acidic but bromelain is an proteolytic enzyme rather than an acid. It breaks down proteins. Enzymes do not behave in the same way as acids, as they do not actually react. They are catalysts that speed up the reactions of other things. Pineapple juice does, however, contain several organic acids such as citric and malic acid.

[rosieposie]

In some respects you are correct Ken.  Tinned pineapple and processed pineapple juice are indeed mildly acidic, however, fresh pineapple as farmed today, are grown in a way that allows them to ripen without bacterial intervention, therefore are either extremely low acidic, neutral or alkaline. It is this fact along with the presence of bromelain as an anti-inflamatory enzyme that allows patients with arthritis and rheumatoid arthritis to consume large daily amounts without suffereing indigestion.  Pineapple also is alkali-forming so also helps to reduce the stomach acid.  It is these facts that we use to recommend the ingestion of fresh pineapple on a daily basis to all our patients.  The one drawback in 'prescribing' daily fresh pineapple for some patients, is that those with more sensitive oral mucosa ( ie those who have been on large doses of prednisolone to suppress the inflammatory process) may find that they are more susceptible to mouth ulcers and therefore may need to take bromelain tablets for the same therapeutic effect.

However, back to cleaning glass.....I think I have  :hj: this thread for long enough!!

[Lustrousstone]

I think you are confusing alkali forming (alkalising) foods with alkalinity. Fruit acids + fruit sugars are the basis of fruit flavours. I can see that you could have less-acidic pineapples but not alkaline ones. Vitamin C is an acid just for a start. Even a banana is pH 4 to 5 ish and a cucumber is 5-ish.

I suspect the nutritionists are looking at things in a different way to the chemists (like me) and not quite hitting the spot with the actual basic science. The pH of the ash, which is something nutritionists seem to cite, is pretty irrelevant to the raw fruit's chemistry.

Raw fruit involves complex organic (carbon-containing) acids. Producing ash from fruit reduces the chemistry to inorganic, which is much less complex and where alkalinity involves things like sodium and potassium hydroxide.

[chopin-liszt]

Enzymes are themselves proteins and will be severely damaged by heat.
Proteins have a "quaternary" structure - the first being the string of amino acids, the second being how that string is folded, the third being how that structure is folded and the quaternary structure is how that one is folded.
Heat destroys these delicate and prescise foldings.

[Cathy B]

Anne, whatever turned out to be the cleaning agent in pineapple, I think I'd be more concerned about consuming the juice it after it had removed whatever it was that was clouding your jug, since presumably that would be dissolved in the liquid...

[chopin-liszt]

Too much pineapple and you'll be dissolving/cooking your insides!

(meat can be "cooked" by injecting it with pineapple juice)

[Paul S.]

....anyway - back to glass.    Two pieces that were heavily clouded/limescaled when first bought (boot sales) - and which I had assumed would be cleaned without too much trouble, although unfortunately not the case, and both proved difficult.   After the recent comments re lemons and citric acid, I filled the Webb's stem vase with neat freshly squeezed juice and left for 24 hours - but no improvement that I cud see.  I tried copper balls/aluminium oxide/metal polish, but there's no room in the stem to swing a cat, so no velocity for the balls to reach and very little improvement.       Resorted to Dirk's narrow brush on a wire, propelled by a cordless drill, and after lots of patience and cerium oxide/metal polish, reached the improvement you see  -   about 90% I guess.      So, anyone want to buy three cwt. of lemons.
The W/Fs. is obviously the easier piece to get at, although the felt mop on the drill was almost getting me nowhere  -  so resorted to manual use of a nylon body scrub pad/wire wool  -  which removed the cloudiness, but left behind the marks typical of wire wool.    Used a flexible drive (from a mains drill) with a compressed felt wheel, plus metal polish/cerium oxide, and eventually achieved the result you see.    Again, probably something like a 95% success rate (slightly better than the Webb's - I think).   I'm in two minds as to whether the nylon pad is damaging  -  we know the wire wool can be  -  but I might give more thought to using the nylon pad.     If you can get inside the piece, then wire wool is a useful material  -  provided you accept that time must be spent polishing out the feint abrasive marks afterwards.
Believe both of these pieces had glass sickness rather than simple limescale deposits  -  but goes to show that with patience even bad pieces can be brought back to a useful life, provide you accept that some examples may require a lot of time spent on them.