The isinglass in my wine kit is cloudy. Has it gone bad?

Question

I bought a Wine Experts Pinot Grigio wine kit and the packet of isinglass is cloudy and has white bits floating around in it. I suspect it is bad. Has anyone seen that before?

Answer 1

I have never used isinglass, but was sufficiently interested to read around the subject a bit.

It seems like that if you are talking about liquid isinglass, it does have a fairly limited shelf life. This website [1] suggests that isinglass has a shelf-life of 4 - 8 weeks tops if stored at below room temperatures. Above 20C / 68F the proteins in it can denature (alter the protein structure). This can lead to white lumps floating in the surface of the liquid.

Sounds a bit like what you are seeing. It is possible that the kit was stored at too high a temperature prior to purchase.

The same website suggests that it is better to use powdered isinglass or flocs (==flakes) since these have a better shelf life and are easier to store.

[1] http://www.practicalbrewing.co.uk/fining/page5.html