Back Sweetening - Bench Trial Approach

[syncnite]

Can someone verify my calculations and process? I wanted to document a simple reference for back-sweetening fruit wine, including simple calculations.

Below is quick reference for adding sugar to a finished wine. You can scale this up or down easily if you want a sweeter wine or a slightly sweet (off-dry) wine. I used these measurements for a bench trial to back-sweeten a strawberry wine after it bulk-aged for 6 months.

Start with:

• 4 glasses.
• Graduated cylinder or a beaker with measurements up to 100ml.
• Sugar/water solution with 20g of sugar mixed with enough water to result in 50ml solution (water warmed up to dissolve the sugar, then cooled again to room temp).
• Base wine at the temperature at which you intend to enjoy it in the future (i.e. refrigerated for summer fruit wine).

For each sample, first measure the sugar water solution into a graduated cylinder or a beaker, and then add wine up to 100 ml total.

Glass 1 - no sugar just the base wine
Glass 2 - wine + 5 ml sugar solution (20 g/l)
Glass 3 - wine + 15 ml sugar solution (60 g/l)
Glass 4 - wine + 25 ml sugar solution (100 g/l)

Taste all four, decide which you like best. You can alway increase the amount of sugar if glass 4 is still too tart. If, for example you liked glass 3, then you can scale up for a 6 gallon carboy (23 liters): 60 g/l X 23l = 1380 g sugar.

 

[DoctorCAD]

Make enough to measure its SG, make the carboy the same SG as the sample you like (or a tiny bit less as going over cant be fixed!).

 

[BernardSmith]

IMO, your idea is in the right place but the problem is in the way you are adding your sugar. Each time you double the amount of sugar you are also adding more liquid and so diluting the sample, so your target is always moving. If this were me I would dissolve the sugar directly in each glass by stirring or alternatively I would make different batches of dissolved sugar using the same volume of liquid (so no matter how many gs of sugar you were adding you would always only add X CCs of liquid to each glass. AND you can also then decide that glass 3 is not sweet enough and glass 4 is too sweet and so you start a second test using glass 3 as your base and increasing the amount of sugar you add until you reach a qty shy of the original fourth glass.

 

[cmason1957]

I do this by adding successive 1/4 tsp to each sample, no extra water. Then scale that up from 100 ml to 23 liters.

 

[salcoco]

your technique is sound. I prefer smaller increments of sugar . I use 100ml of wine and a sugar syrup of 2 cups sugar to one cup water. I mix mine in a blender with hot water from the tap. for each glass i use a 1/4 tsp which is 1.25ml. increase by one for each sample. calculate the amount of syrup required based on ratio for final wine. the amount of water used to for this bench trial is very small compared to the amount of wine. this is not a organic chemistry class. Using the syrup will insure that all of the sugar dissolves in the wine. just enjoy. remember the wine will become sweeter over time .

 

[ErikM]

What is the advantage of using a sugar solution? I just disolve the sugar right in the wine. 1g sugar in 100ml wine = 1% rs. 2g sugar in 100ml wine = 2%rs. I do rs bench trials (taste tests) a often.

 

[Stressbaby]

I agree with above, I use straight sugar. Most of my batches are small, making bench trials somewhat challenging because you are forced to use small samples. I use the following formula:

1/8tsp sugar in 37.5ml wine = 50g sugar/gallon = 1/4cup sugar/gallon

1 cup sugar in a gallon raises SG about 0.019; 1 cup sugar is 200g, so 1/8t in 37.5ml is equivalent to a bump in SG of just under 0.005.

I also agree with smaller increments, but I really don't like sweet wine and almost never go over about 75g sugar per gallon.

 

[salcoco]

I always found the sugar solution does not require any mixing to insure dissolving the sugar in the final batch. Basically it is easier and more reliable.

 

[Frontporchwines]

DoctorCAD you are correct. The down right easiest method.