Adding Raisins when making Wine. Setting the Record Straight on WinemakingTalk.com
I would like to thank Zac for this contribution. I decided to take Bzac’s comment on our Winemakingtalk.com Fact Check Service and re-post it as a separate blog piece. The information below is too good to get lost in the comments.
The adding raisins post primary came up on www.winepress.us from someone who saw it on WinemakingTalk.com. the infection of bad advice spreads! anyway here are my thoughts on the practice.
I used to add raisins to kit wines during primary ferment to give the some more tannin and body.
These were very cheap 4 week kits .
After much experimentation and many kits , I stopped using raisins , instead tweaking kits with real grapes I had crushed stemmed and frozen in 5 pound bags . I’d add a bag or two to a kit or juice pail.
There are some fundamental problems with using raisins in a grape wine.
The primary one is that they are so oxidized and browned they contribute these sherry like oxidized flavours to the wine.
With cheap 4 week kits the oxidized character was masked a bit by the challenging flavours of high levels of concentrate in a 4 week kit (KT) when young , but as the wine ages these oxidized flavours from the raisins become very noticeable when the wine has been in the bottle for a year or two.
With a juice pail or higher end kit with lower levels of concentrate the oxidized character from the raisins is noticeable pretty much from the get go.
This is why the kit industry moved away from including raisins to supplying grape packs . Ask Tim Vandergrift , he’ll tell you directly that’s why WE don’t use raisins , favoring grape pack instead.
Adding raisins to a wine post primary (after the initial batch is dry) is a weird choice and risky.
Adding more sugar post primary does introduce problems. The worst of which is a much increased risk of h2s because the yeast has used up the must’s nutrient , adding more is not a good idea at such a late stage because the yeast population is already at the end of its life cycle . Additional nutrient would also become fodder for spoilage organisms.
Adding raisins during primary , the large active yeast population will metabolize and buffer some of the raisins tannins and oxidized character mitigating some of the negative aspects of using an oxidized product in your wine . But adding them later misses this benefit so the oxidized character will be bolder in a “secondary ” raisin addition.
Adding raisins after primary also greatly increases the risk of a stuck fermentation as the weakened and spent yeast population being reintroduced to sugar can get stuck , leaving residual sugar in your wine and all the problems associated with that.
Adding MLB and raisins together does increase your risk to, there is a potential for increased levels of Volatile acidity and the MLB also increases the likelihood your raisin sugar ferment will get stuck , again introducing all the problems with that. This is even more likely given your spent and weak yeast population.
In summary , as someone who has years of experimenting with kits and pails and has dozens of unsuccessfully tweaked batches under his belt , I would strongly advise against post primary raisin additions . Save your raisins for country wines using dark fruit.
Adding raisins post primary is just about the worst advise I’ve ever heard of.
If you want more tannin and better mouth feel , adding enological tannin and SIY products will produce much better results. So will buying a lug of grapes , crushing and stemming them and freezing them in 5 pound zip locks , one 36 pound lug will give you enough grapes to tweak 3 to 6 kits or pails , just make sure you add them during primary.