Oct 2012
Allergic to Sulphites - Not so!
October, 2012 Filed in: Wine making
I thought Tim Vandergrift’s blog post(Winexpert’s Technical Manager) this month was particularly enlightening on the commonly asked question about why some people can drink kit wine and not commercial wine without getting a headache...
One of the things I hear frequently from people who find out I'm a technical guy for winemaking is, "I'm allergic to the sulphites in wine. What can I do?" Twenty years ago, after approximately the hundredth time I heard this, I started to get a little short with my answers. In my justification, sulphite allergies are such an all-pervasive myth that it seems like an endless tide of misinformation to stand against, and even some of the people who should know better (like wine educators and salesfolk) sometimes give the impression that there's some validity to the idea that sulphites are in some way contributory to allergic responses or headaches from wine.
Fortunately for my continued work as a wine guy, I realised that if I didn't give the good information, it was my own darn fault if people didn't learn the truth. To whit: human beings can't be 'allergic' to sulphite. An allergy is an inappropriate immune-system response. Sufferers have excessively active white blood cells: when an allergen binds to the mast cells or basophils they produce antibodies that cause an inflammatory response, which can range from mildly annoying to lethal.
Sulphite, a stable salt of elemental sulphur cannot provoke this immune response--it just does not work this way.
Common protests against this statement are,
'What about sulfa drugs?'
The class of drugs known as 'Sulfa' (actual name, 'Sulfonamides') don't contain any sulphur in any form. The two aren't chemically related. It's like claiming to be allergic to pencils because you are also allergic to penicillin.
What about asthma? Sulphites trigger asthma.
Lot's of things trigger asthma that are not allergens. When very high concentrations of sulphite dust or the vapour from a liquid solution comes in contact with mucous membranes (like the alveoli in your lungs) the moisture in them combines to make sulphuric acid. That makes everyone's lungs cramp, not just asthmatics, but it's not an allergy.
I'm allergic to sulphite. You're not an allergist!
No, I'm not. But you're not allergic to sulphite either. I wouldn't possibly comment on this issue without a major backstop--the corporate liablity for it would be horrifying. My source is Dr. Janice Joneja, a pretty darn smart person and a renowned expert on allergies. She's far more adamant about the allergic potential of sulphite in winemaking than I'll ever be (in addition, she's extremely patient and generous with her time towards geeky wine tech guys--thanks Dr. J.)
So, what is it that causes people's problems with wine? Shunting aside the obvious (drinking too much wine) the biggest contributor to negative response to wine consumption is bio-amines. Plants produce these as natural defenses against predators, and they work. In humans they provoke immune response, and are the reason why people take antihistamines.
Ripe grapes don't contain massive amounts of bioamines, and the yeast that causes the fermentation process doesn't add significant quantities of them either. The bio-amines in wine generally come from a secondary fermentation treatment known as 'malolactic fermentation', or MLF. MLF is caused when a bacteria (typically a cultured one added to commercial wines on purpose) consumes the malic acid in wine and converts it into lactic acid. This can be desirable for two reasons: first, malic acid is pretty harsh, tasting like green apples, while lactic acid is softer and easier on the palate. Second, a by-product of MLF is the compound diacetyl, which lends a buttery or melted butter aroma to the the wine. This is so strong that commercially synthesised diacetyl is the flavour ingredient used in microwave popcorn (which is why they call it 'buttery' rather than 'buttered'). MLF is normally only executed on red wines, some Chardonnays and very few other whites.
Unfortunately the bacteria also produce bioamines, and these are probably the source for most people's allergic response to wine--since only a few whites get it, it's the source of the 'red wine headache' trope.
The super-ultra-hooray-for-me good news is that kit wine never undergoes MLF--I can no longer count the number of times people have told me that they can't drink commercial wine, but are able to enjoy their own home produced wine from my kits. This is just another of the uncountable reasons why it's an absolute genius move to buy wine kits from me and make your own wine for your own self.
One of the things I hear frequently from people who find out I'm a technical guy for winemaking is, "I'm allergic to the sulphites in wine. What can I do?" Twenty years ago, after approximately the hundredth time I heard this, I started to get a little short with my answers. In my justification, sulphite allergies are such an all-pervasive myth that it seems like an endless tide of misinformation to stand against, and even some of the people who should know better (like wine educators and salesfolk) sometimes give the impression that there's some validity to the idea that sulphites are in some way contributory to allergic responses or headaches from wine.
Fortunately for my continued work as a wine guy, I realised that if I didn't give the good information, it was my own darn fault if people didn't learn the truth. To whit: human beings can't be 'allergic' to sulphite. An allergy is an inappropriate immune-system response. Sufferers have excessively active white blood cells: when an allergen binds to the mast cells or basophils they produce antibodies that cause an inflammatory response, which can range from mildly annoying to lethal.
Sulphite, a stable salt of elemental sulphur cannot provoke this immune response--it just does not work this way.
Common protests against this statement are,
'What about sulfa drugs?'
The class of drugs known as 'Sulfa' (actual name, 'Sulfonamides') don't contain any sulphur in any form. The two aren't chemically related. It's like claiming to be allergic to pencils because you are also allergic to penicillin.
What about asthma? Sulphites trigger asthma.
Lot's of things trigger asthma that are not allergens. When very high concentrations of sulphite dust or the vapour from a liquid solution comes in contact with mucous membranes (like the alveoli in your lungs) the moisture in them combines to make sulphuric acid. That makes everyone's lungs cramp, not just asthmatics, but it's not an allergy.
I'm allergic to sulphite. You're not an allergist!
No, I'm not. But you're not allergic to sulphite either. I wouldn't possibly comment on this issue without a major backstop--the corporate liablity for it would be horrifying. My source is Dr. Janice Joneja, a pretty darn smart person and a renowned expert on allergies. She's far more adamant about the allergic potential of sulphite in winemaking than I'll ever be (in addition, she's extremely patient and generous with her time towards geeky wine tech guys--thanks Dr. J.)
So, what is it that causes people's problems with wine? Shunting aside the obvious (drinking too much wine) the biggest contributor to negative response to wine consumption is bio-amines. Plants produce these as natural defenses against predators, and they work. In humans they provoke immune response, and are the reason why people take antihistamines.
Ripe grapes don't contain massive amounts of bioamines, and the yeast that causes the fermentation process doesn't add significant quantities of them either. The bio-amines in wine generally come from a secondary fermentation treatment known as 'malolactic fermentation', or MLF. MLF is caused when a bacteria (typically a cultured one added to commercial wines on purpose) consumes the malic acid in wine and converts it into lactic acid. This can be desirable for two reasons: first, malic acid is pretty harsh, tasting like green apples, while lactic acid is softer and easier on the palate. Second, a by-product of MLF is the compound diacetyl, which lends a buttery or melted butter aroma to the the wine. This is so strong that commercially synthesised diacetyl is the flavour ingredient used in microwave popcorn (which is why they call it 'buttery' rather than 'buttered'). MLF is normally only executed on red wines, some Chardonnays and very few other whites.
Unfortunately the bacteria also produce bioamines, and these are probably the source for most people's allergic response to wine--since only a few whites get it, it's the source of the 'red wine headache' trope.
The super-ultra-hooray-for-me good news is that kit wine never undergoes MLF--I can no longer count the number of times people have told me that they can't drink commercial wine, but are able to enjoy their own home produced wine from my kits. This is just another of the uncountable reasons why it's an absolute genius move to buy wine kits from me and make your own wine for your own self.