What is a sloe? And which type of yeast?

I worry about spoilage. How can you tell if a batch is ruined?

Annnnd the fun begins!

This is the Wikipedia explanation of a Sloe. Basically the plums and sloes provide a source of sugar, flavour, and 'depth' to the wine. You may well be able to compensate by substituting nectarines for the sloes - this sort of experimentation is part of traditional home winemaking.
{Also some people have told me that the best wine is made with fruit that is bruised or going soft as the natural winemaking process is underway}

After I logged out I had another look through my Craft notes and came across this recipe for Blackberry Mead

"Boil one pound of barley in 5 quarts water for 12 mins (timed). Stand for one minute, then pour all the water off the barley.
Add to this water 6 pounds ripe blackberries, 1 pound black plums, and boil for 15 mins.
Strain and add 1 pound of honey to each quart and stir it away [stir until it dissolves]

All timings to be exact"

Add to fermentation demijohn, and proceed as usual winemaking.

The key to keeping the brew from spoiling is keeping all the equipment clean in the first place. I tend to rinse everything I can in boiling water before use, make sure I sterilise the jar or glassware used in the secondary fermentation. Then keep the fermentation in the bucket tightly covered with one layer of thick cloth, or several layers of thin ones. This keeps the vinegar fly out which is the main spoiler of home-made wine.

Sometimes there is a little bit of mould on the pulp in the bucket- just carefully remove it with a large spoon.

Also I used rainwater where possible filtered through cloth and well boiled.

You can get all sorts of yeast these days. In the time these recipes were written there was only bakers yeast, or relying on the natural yeast on the fruit itself. I'd start with the stuff in the bread aisle made up as like the suggestions on the packet. If you can get yeast paste and use it on toast so much the better.

As to tell when a batch is ruined- when it won't ferment, goes an interesting colour, or smells 'odd' are about the best indications.
Once the yeast starts 'working' it usually out-breeds any noxious bacteria and the positive pressure and pooling of the resultant CO2 acts as good protection too.

Wonderful. Thank you Ian!

Sounds quite interesting but it is a bit labor intensive for me. I don't have the time, but if anyone here makes it please let me know how it turns out.

My pleasure Veda. Even more fun if you can spare a cauldron to start the must (ingredients) in. You'd have a self-seething cauldron without need of a fire!

A cauldron......very neat, Ian!

That's a beautiful image you've conjured up Ian