Wine and the vegan connection

We held a weekend lunch where one of our friends brought a new partner, who recently turned vegan. I knew in advance so I cooked a couple of vegan dishes as part of the meal. After the couple left, another friend pointed out that the wine they brought wasn't vegan. I feel put out after making an effort with the food. What do you think?

I can see why, if you will pardon the pun, you feel cheesed off – much in the way that restaurant chefs who have devised a special menu for gluten-intolerant customers can't help feeling sceptical when they witness said customers enjoying the meal with a refreshing, gluten-rich ale.

Making jokes at vegans' expense is – to use a not-very-vegan-friendly expression – like shooting fish in a barrel. I shall refrain and suggest that you give your friend's new squeeze the benefit of the doubt. Not everyone knows that traditional winemaking processes can involve milk, eggs, or an old-school product called isinglass, derived from fish bladders. Icky though it sounds, it's been happening for hundreds of years.

Be assured that this stuff doesn't end up in the bottle except, perhaps, in minute traces. The products in question are not additives. They are used mainly to clarify naturally hazy wine and sometimes to remove bitter flavours that come from grape skins and seeds; then they are discarded. Stirred into a vat of wine, these "fining agents" bond with the tiny particles that make wine cloudy or bitter. The union makes them sink and the wine is poured off, leaving the sediments behind.

None of this means vegans need to lay off the vino. In Australia, wines "fined" with dairy or egg products are easily identified – there's a legal requirement to note this on their labels. There is no law requiring declaration of isinglass; to be sure of avoiding it, actively seek out wines that are sold as suitable for vegetarians. There are plenty: wine can be fined with other, non-animal substances. Some wines are not clarified at all.

All of this is quite a lot to get one's head around. If your vegan guest is relatively new to shunning all things animal, she is likely to be grappling with more pressing problems than the fine print on wine labels. These challenges may include cheese withdrawal; being trolled at every meal; and unprecedented interest in her footwear ("so are those sandals you're wearing leather?"). Cut her some slack – she'll work it out soon enough.