Sultana wine

[tonyhibbett]

The method I use now extracts virtually all of the sugar within 24 hours, but some flavour remains in the pressed pulp. Since my intention is to make dry white wine, I don't want the raisin flavour to be prominent. The same applies to colour extraction. So far so good with the Turkish sultana batch, but raisins have a stronger flavour and are darker.
Regarding the red wine, the preferred method is to rack towards the end of primary fermentation, to remove the thick sediment, then leave the fermentation to complete and let the wine stand on a thin layer of dead yeast, which enhances the flavour. The wine is racked again after a month and can then be bottled and left at least a month. If you did not rack after the primary fermentation, there will be too much dead yeast to leave, so you must rack it. As the wine clears, there will be some sediment anyway after a month.

 

[tonyhibbett]

I strained and wrung the raisin batch which left 950 g of pulp. This may seem a lot, but it's the same amount from the equivalent 6 kilos of fresh grapes. While it is possible to make a smaller, lighter batch from this pulp by mixing it with half a gallon of hot water and 400 g of sugar, the resulting wine would be rather insipid unless you added a litre of apple juice instead of water.
Now I have a gallon of brown 'juice' with sg 1113, which means virtually all of the sugar has been extracted. Not all demijohns hold 5 litres, so it's best to leave topping up until the fine pulp has settled in the jar.
Once racked off the fine pulp, I topped up the liquid with enough water to reduce the sg to 1090. This required almost a litre of water, which also diluted the acid. I corrected this with 5 g of tartaric acid, plus a teaspoon of tannin. The pH is now 3.4, which is about right. I then stirred in the yeast and poured the lot into the demijohn, with 5 g oak chips. The volume is now 1 gallon of pulp free liquid. The strong raisin flavour is now far less prominent.
Total cost about £3.50.
I noted that the sultanas have more sugar than the raisins - 73.6 % compared with 69.3 %, by weight.

 

[tonyhibbett]

So what's the difference between sultanas and raisins? Turkish sultanas are made from, unsurprisingly, Sultana grapes, whereas California raisins are made from Thompson Seedless grapes. Since both varieties are 'seedless', they are preferred as table grapes and for the production of white grape juice concentrate. Also, being seedless, they are deficient in tannin. The grape tannin I use is extracted from grape seeds. Dried grapes are also rather low on acid, especially if sun dried. The riper the grape, the lower the acidity. These are the main reasons why wine made from dried grapes and concentrates can taste somewhat lifeless, like that grim stuff known as 'British wine'. Does anyone remember 'Wincarnis' and 'Sanatagen'? Best forgotten!
Sometimes dried grapes are used in winemaking to supplement a poor harvest. That's not the whole story, of course and the use of dried grapes to make wine goes back thousands of years.

 

[tonyhibbett]

Siphoning off small quantities like 1 gallon is a bit wasteful. I poured the fine pulp sediment into 2 jugs and let it settle. From 1.4 litres of pulp I was able to salvage 300 ml of the precious 'clear' liquor by using a syringe. This may not seem a lot, 6% overall, but will ensure that I do actually get 6 full bottles of wine as a result.

 

[tonyhibbett]

The sultana batch is going well but tastes rather bland. So I added 5 g of tartaric acid which, strangely, caused it to fizz dramatically. It now has a fresher taste. The pH is now 3.5. I added 5 g of oak chips.
The raisin batch has a thin layer of dark scum now that fermentation is well under way. The raisin flavour has receded significantly. I added 5 g of oak chips.
I strained the solids pulp again, which left just 600 g of fairly tasteless dryish mush. The liquor had little taste but a surprising amount of sugar, at sg 1030. I added the fine pulp which boosted this to 1040, so salvaging even more from the waste. Once the fine pulp has been removed, I plan to top up the liquor with 2 litres of apple juice plus about 500 g of sugar, which will give me another gallon of wine. It will be very basic stuff but very useful for topping up and blending.

 

[tonyhibbett]

Ideally the fruit should be evenly minced, which is hard to achieve in the food processor unless you have the optional mincer attachment, which costs £27! I went to the local boot fair in search of an old fashioned manual mincer and came back with a heavy duty electric one, for which I paid £20. Clearly intended for a butcher's shop, this will be perfect for processing the large amounts required to make a 5 gallon batch.

 

[tonyhibbett]

What I thought was a meat mincer turns out to be an expensive masticating juice extractor, capable of getting 86% of juice from fresh grapes. I saw a second hand one on eBay at a starting price of £150! If it jams, it not only automatically goes into reverse, but also audibly tells you!
Although not what I intended to get, it offers some interesting possibilities for processing fresh fruit, such as the nectarines I bought from the same boot fair. Watch this space!

 

[tonyhibbett]

I thought I would use this extractor as a substitute for straining and pressing. While it certainly did remove coarse solids and didn't jam, it made the fine particles even finer and less inclined to settle. I mixed in some bentonite which rapidly cleared 40%, but that was all. So it all went back into the bucket, along with yeast.
I have ordered a Salter manual meat mincer. Moral - keep it simple!

 

[tonyhibbett]

The mincer works well but can only handle 50 g at a time. The metal in contact with the fruit are the ground steel cutters and the contact time is so short that there should be no problem with discolouration.