Hello all and anyone,
Has anyone heard of a test that could be performed at home to identify whether a wine has any TCA evident? I would love to be able to drop a strip in a wine to test for TCA, similar to that of using litmus paper to test for acid or alkalinity. I presume the answer is "no" as I am sure that if it were out there, wine nuts like ourselves would be using them.
So, what is the reason that something like this is not achievable?
When you send a bottle wine back to a winery, how do they test for TCA?
Any light would be greatly appreciated.
Kind regards,
Adair
P.S. By the way, I raise this question due to a corked bottle of 2002 Wirra Wirra RSW that I opened last week. Well, I presume it was as it was very thin.
Question: TCA Tester
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Guest
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Guest
Anonymous wrote:Guys
you dont need a kit as you should be able to pick up TCA quite easily with your nose, oxidation seems to be the one that stumps them. the amount of wine that is clearly oxidised yet still served is staggering, from people who should know better
my 2c worth
Guest,
With all due respect, I do not agree and don't believe many, if any, would agree.
In fact, in this Tuesday's Sydney Morning Herald - Good Living section, Huon Hooke dedicated his 2/3rd page weekly article to his (and the other judges and associate judges in his group's) inability to realise that a bottle of 1998 Reynell Basket Press Cabernet Sauvignon was corked, but believed that the wine they were tasting blind was simply not a good wine.
I don't think many knowledgeable people would think anything else than fact that the human nose can not detect TCA at lower levels of taint, yet it still affects fruit depth and flavour of a wine.
Adair
Had a bottle of 2002 Blown Away Bare Bottom Hills Shiraz 2002 the other day which should have 'blown me away' but was flat, lifeless and no fruit to be seen (or tasted). I have been told it was corked (in its early stages). Not a sign of smelly wet socks.
Got another to try this weekend (thanks Carmello).
Regards,
Allan
Got another to try this weekend (thanks Carmello).
Regards,
Allan
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KMP
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I'm not aware of any home kit you can buy to detect TCA. Some of the technology used (e.g. gas chromatography) is pretty expensive and not exactly suitable for the home kitchen. Most wineries would send samples out for testing. Aussie based work includes these folks - look under wine closures. Antibodies to detect TCA? I guess I could have thought of that, and well yes its certainly possible, but there is other work which suggests that other components in wine interfere with the detection so I wouldn't bet the farm on that method just yet. There are also these folks, but the site is old and I haven't chased down any more recent work. Then there is the zNose!
The Australian Wine Research Institute site does list TCA analysis as a service. See here.
Mike
The Australian Wine Research Institute site does list TCA analysis as a service. See here.
Mike
TCA is generally measured by GC/MS, and like others have said I am unaware of any home kits, more to the point, if there were nay on the market, I would be highly sceptical at first.
Other than the larger wineries (and that could possibly be the top five) I dont know of any one running GC/MS for TCA analysis. The cost of testing by the AWRI is also quite prohibitive, reputable cork suppliers, supply QC stats for TCA. There are other systematic trials that should be put into place for QC in the winery, soaking corks over a period of time and looking for taint in the water, amongst many other tests.
In regards to the antibodies I am dont think that they are using them for detection (although I havent read the paper). Reason being, the antibody wouldnt be able to bind to TCA or derivatives. It would have to be bound fistly by a protein or a irreversible enzymaitc reaction so the antibody could bind to the that. Importantly quantification would not be as accurate as GC/MS. I will try and hunt out the paper...
Oxidatoin can work conjunctively with TCA, a wine with taint will show more pronounced TCA characteristics with oxidation.
In general, I think TCA is just accepted as the norm, if you use cork there is a highly likely possibility you will have tainted bottle. Further to this if you use chlorine in the cellar, it is highly likely that you will have clean floors, however a higher incidence of TCA and derivatives.
Cheers
Colin.
Other than the larger wineries (and that could possibly be the top five) I dont know of any one running GC/MS for TCA analysis. The cost of testing by the AWRI is also quite prohibitive, reputable cork suppliers, supply QC stats for TCA. There are other systematic trials that should be put into place for QC in the winery, soaking corks over a period of time and looking for taint in the water, amongst many other tests.
In regards to the antibodies I am dont think that they are using them for detection (although I havent read the paper). Reason being, the antibody wouldnt be able to bind to TCA or derivatives. It would have to be bound fistly by a protein or a irreversible enzymaitc reaction so the antibody could bind to the that. Importantly quantification would not be as accurate as GC/MS. I will try and hunt out the paper...
Oxidatoin can work conjunctively with TCA, a wine with taint will show more pronounced TCA characteristics with oxidation.
In general, I think TCA is just accepted as the norm, if you use cork there is a highly likely possibility you will have tainted bottle. Further to this if you use chlorine in the cellar, it is highly likely that you will have clean floors, however a higher incidence of TCA and derivatives.
Cheers
Colin.
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KMP
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vinum wrote:
In regards to the antibodies I am dont think that they are using them for detection (although I havent read the paper). Reason being, the antibody wouldnt be able to bind to TCA or derivatives. It would have to be bound fistly by a protein or a irreversible enzymaitc reaction so the antibody could bind to the that. Importantly quantification would not be as accurate as GC/MS. I will try and hunt out the paper...
Cheers
Colin.
There are several papers using hapten-carrier methods to attempt to raise TCA specific antibodies, with varying degrees of success. Check out PubMed and search under antibody, 2,4,6-trichloroanisole and then expand that single citation under Related Articles. The problem, of course, is that the hapten-carrier approach while time honored is out dated. I wouldn't mind betting that someone out there is using a high throughput approach with combinatorial libraries screening chemical derivatives. Yes, the molecular geometry would be a challenge but thatÂ’s what they tell me chemists are for
Mike
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Guest
{quote]
There are several papers using hapten-carrier methods to attempt to raise TCA specific antibodies, with varying degrees of success. Check out PubMed and search under antibody, 2,4,6-trichloroanisole and then expand that single citation under Related Articles. The problem, of course, is that the hapten-carrier approach while time honored is out dated. I wouldn't mind betting that someone out there is using a high throughput approach with combinatorial libraries screening chemical derivatives. Yes, the molecular geometry would be a challenge but thatÂ’s what they tell me chemists are for
Mike[/quote]
Note: post wrtitten post lunch, including several beers...
I dont doubt that people are running such screens Mike, however the rudiments are still the same, you still have to make the antibody, which is time consuming and can be costly. I am not denying the merit of this research, being partially industry research based, I think its really exciting, just pointing out the limitations as I see them, in regards to the Australian Wine Industry. Especially given the achievable results using GC/MS. Additionally, having run high throughput, albeit transcription screens, I see the limitations in terms of feasibility of application within the Industry or research base (well at least in Australia and New Zealand). This all combined with the fact that grants in the wine industry are not quite as 'frequent or maybe lavish' as they are within, say medical research. Furthermore, in regards to Aus, with very few molecular wine groups, I think we would be stretching capabilities on the home front. Apologies if you feel I am harping on, industry research is key component for growth and something I feel passionate about, I would however be keen to hear further ideas.
Cheers
Colin.
There are several papers using hapten-carrier methods to attempt to raise TCA specific antibodies, with varying degrees of success. Check out PubMed and search under antibody, 2,4,6-trichloroanisole and then expand that single citation under Related Articles. The problem, of course, is that the hapten-carrier approach while time honored is out dated. I wouldn't mind betting that someone out there is using a high throughput approach with combinatorial libraries screening chemical derivatives. Yes, the molecular geometry would be a challenge but thatÂ’s what they tell me chemists are for
Mike[/quote]
Note: post wrtitten post lunch, including several beers...
I dont doubt that people are running such screens Mike, however the rudiments are still the same, you still have to make the antibody, which is time consuming and can be costly. I am not denying the merit of this research, being partially industry research based, I think its really exciting, just pointing out the limitations as I see them, in regards to the Australian Wine Industry. Especially given the achievable results using GC/MS. Additionally, having run high throughput, albeit transcription screens, I see the limitations in terms of feasibility of application within the Industry or research base (well at least in Australia and New Zealand). This all combined with the fact that grants in the wine industry are not quite as 'frequent or maybe lavish' as they are within, say medical research. Furthermore, in regards to Aus, with very few molecular wine groups, I think we would be stretching capabilities on the home front. Apologies if you feel I am harping on, industry research is key component for growth and something I feel passionate about, I would however be keen to hear further ideas.
Cheers
Colin.
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KMP
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Reader caution BS, piled higher and deeperÂ…Â…Â…
Colin
Being an expat I sympathize with folks trying to get real money for research in Oz; thatÂ’s one of the reasons I moved to the USA. IÂ’ve been working with antibodies for a long time so they always seem to me to be simple to work with. Combinatorial libraries are simply libraries of antibody heavy and light chain cDNAs allowed to randomly combine so that you get antibody combinations that might not otherwise form following immunization. They can be screened in many different ways. There are problems with affinity etc., but they can be dealt with in imaginative ways. Oddly enough one source of material for such libraries is nonimmunized human donors.
I havenÂ’t read the details of the anti-TCA antibody studies that have been published so I donÂ’t have a clear idea of their potential. But I can appreciate that the reason behind the work is that an antibody assay would be inexpensive, portable, and relatively idiot-proof (especially if it was made into a positive/negative format) compared to GC/MS. Whether it would get down to the required sensitivity is something that would need looking into, but these assays can be amplified so as long as the signal-to-noise ratio could be kept under control it might be OK.
(In a perfect world) if I was a cork manufacturer (or a big wine maker) I would want a couple of assays for TCA. One would be the gold standard (probably keep GC/MS) for rigorous quality control and another would be a screening assay that I could use to do spot checks on corks and wine under cork. Being relatively inexpensive a screening assay would be useful to smaller winemakers as well.
The question is how sensitive do you want the screening assay to be for TCA? If its too sensitive youÂ’ll pick up its presence when its not likely to be a concern for the wine drinker. If you make it so that it detects a range of TCA levels that can be detected by most wine drinkers then you run the risk of having a test that is equivalent to the human nose. And most winemakers would consider their nose a cheap employee! Of course you could employ a marketing firm to convince folks that it was a great invention and blind them with science!
If it was a cheap, sensitive and reproducible test then it would be useful. It would produce less debate than five or six noses gathered around a bottle, all sniffing away, describing different aromas and arguing whether it is TCA.
Mike
Colin
Being an expat I sympathize with folks trying to get real money for research in Oz; thatÂ’s one of the reasons I moved to the USA. IÂ’ve been working with antibodies for a long time so they always seem to me to be simple to work with. Combinatorial libraries are simply libraries of antibody heavy and light chain cDNAs allowed to randomly combine so that you get antibody combinations that might not otherwise form following immunization. They can be screened in many different ways. There are problems with affinity etc., but they can be dealt with in imaginative ways. Oddly enough one source of material for such libraries is nonimmunized human donors.
I havenÂ’t read the details of the anti-TCA antibody studies that have been published so I donÂ’t have a clear idea of their potential. But I can appreciate that the reason behind the work is that an antibody assay would be inexpensive, portable, and relatively idiot-proof (especially if it was made into a positive/negative format) compared to GC/MS. Whether it would get down to the required sensitivity is something that would need looking into, but these assays can be amplified so as long as the signal-to-noise ratio could be kept under control it might be OK.
(In a perfect world) if I was a cork manufacturer (or a big wine maker) I would want a couple of assays for TCA. One would be the gold standard (probably keep GC/MS) for rigorous quality control and another would be a screening assay that I could use to do spot checks on corks and wine under cork. Being relatively inexpensive a screening assay would be useful to smaller winemakers as well.
The question is how sensitive do you want the screening assay to be for TCA? If its too sensitive youÂ’ll pick up its presence when its not likely to be a concern for the wine drinker. If you make it so that it detects a range of TCA levels that can be detected by most wine drinkers then you run the risk of having a test that is equivalent to the human nose. And most winemakers would consider their nose a cheap employee! Of course you could employ a marketing firm to convince folks that it was a great invention and blind them with science!
If it was a cheap, sensitive and reproducible test then it would be useful. It would produce less debate than five or six noses gathered around a bottle, all sniffing away, describing different aromas and arguing whether it is TCA.
Mike