Has sugar lost its sweetness?

[Pinot Col]

I have a recipe for frozen summer fruits which goes: 1 kg bag fruit +1 kg sugar, make up to 4.5 litres etc, etc.
At room temparautre the gravity of this 4.5l reads 1.065 and I was expecting 1.090 which means, according to CJJ Berry's tables, an outcome of around 8.6% ABV with 760 grammes sugar in solution. If the fruit has 59g of sugar in a kilo, and I am adding 1kg, the outcome ought to be around 12%. An explanation might be that today's sugar is not as sugary as it was in CJJB's day, but that isn't likely.
Here's another recipe that confuses me (this from homemadewinerecipes.co.uk) which uses 1 litre pure apple juice (10% sugar = 100g) + 1kg sugar + 200g sultanas (60% sugar = 120g). Total sugar = 1225g which in 4.5 l water could yiled 14% ABV. The recipe introduction says it should make a wine of about 10% ABV
What am I not getting right?

 

[Clint]

Don't make wine but a few things to consider...
Your hydrometer is knackered.
You're assuming sugar content.
It's not mixed in properly.

 

[Pinot Col]

Don't make wine but a few things to consider...
Your hydrometer is knackered.
You're assuming sugar content.
It's not mixed in properly.

The hydrometer reads 1000 in tap water. Sugar content is as package data. It is mixed thoroughly. But thank you for your input.

 

[LottieWine]

I think your recipe is a little short on fruit and sugar.

I make wine from blackberries from my allotment site. I use 1.5kg fruit and 1.2kg of sugar, but I do adjust the sugar content depending on how sweet the fruit is. I aim for an original gravity of 1095. Recipe is from River Cottage - Booze by John Wright. Makes a lovely wine. Last batch I drank, I was a little short on blackberries so I used up half a bag of frozen berries from the freezer. Worked out well.

 

[LottieWine]

According to the calculation tables your must has a brix of 15.9 and a potential abv of 8.8%. To get to 1090/ brix 21.6 you definitely need to add more sugar. According to the chaptalization calculator above you need to add 8.55oz

 

[Pinot Col]

I think your recipe is a little short on fruit and sugar.

I make wine from blackberries from my allotment site. I use 1.5kg fruit and 1.2kg of sugar, but I do adjust the sugar content depending on how sweet the fruit is. I aim for an original gravity of 1095. Recipe is from River Cottage - Booze by John Wright. Makes a lovely wine. Last batch I drank, I was a little short on blackberries so I used up half a bag of frozen berries from the freezer. Worked out well.

Hello Lottie. Thanks for yours. And thank you for telling me about Brix; I didn't know of it or him. I remain wondering about sugar 'sweetness' especially what differences there may be between cane and beet, castor and gran. I expect castor has more sugar in a kilo as it is ground much finer than granulated. agree entirely about blackberry wine; my finest ever when I was off work with a bad back but I managed to work my way along a blackberry hedge one autumn. The wine tasted of autumn sunshine and blackbirds' song!