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Author: Subject: Vanillin purity
Mailinmypocket
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[*] posted on 1-5-2014 at 04:33


They seem to have disappeared! That is too bad... This would probably be a good bet though:

http://m.ebay.com/itm/VANILLIN-100gm-Chemical-Methoxy-Hydrox...
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Boffis
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[*] posted on 12-10-2018 at 08:04


I came to use some vanillin recently that I bought from one of the suppliers discussed above (MinH2O) in 2014 and I too found that it was very impure so I have analysed it.

I first tested it with water and found that most was soluble in water so I leached it with its own weight of warm water (252g in 250ml of water) then chilled it to lab temperature (circa 12 C). The insoluble material was filtered off using vacuum and a Buchner funnel, filtration was slow due to the rather viscous nature of the solution. The cake was air-dried for a couple of days in the house (circa 20 C) to a constant 74.2g, I didn't want to heat it as vanillin is fairly volatile. The filtrate was clear and slightly thick and hard to crystallise but the dried residue carbonized instantly with a few drops of conc sulphuric acid and is almost certainly sugar (ie sucrose). The dried cake therefore weighed roughly 29% of the original weight. The cake was partially soluble in isopropanol so I leached the entire mass with 60ml of hot isopropanol, filtered and then wash the cake with a little more isopropanol. The cake was dried and weighed to give 37.8g of soft, white, very fine material resembling kaolin and smelling of vanilla but was completely combustible leaving little ash and also blackened by conc sulphuric acid; I think this material is probably microcrystalline cellulose filler. The isopropanol filtrate was evaporated slowly to yield an off-white oil which crystallised on standing. The yield was 36.4g of cream coloured solid Mp 78-80 C (Vanillin Mp 83-84 C).

Conclusion: Given that I didn't dry the various fractions rigorously the results are only approximate but it appears that this "vanillin" fom this supplier is roughly 70% sugar, 15% cellulose filler and 15% vanillin proper. There are better suppliers still out there on ebay and amazon.
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[*] posted on 23-10-2018 at 05:41


A big chunk of the world's synthetic vanillin comes from a manufacturer called 'Rhodia'. Not too hard to track down and buy 0.5kg tins of pure vanillin powder (blue Rhodia branded) from bakery suppliers, and we can testify that it's the real deal. A few Chinese suppliers as well who are also claiming to produce 99.9% product, and slightly cheaper, but haven't tried them out. If you buy in small quantities for home baking, generally it comes adulterated with sugar, anti-caking agents, etc.



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