I tried measuring brix on a shriveled up fig just like pictured above in post #31. I couldn't get a reading either by rubbing the cut surface onto the meter or the way shown on the video, gobbing some on and mushing it down. The seeds wouldn't let me get it flat enough.

So I tried it on a firm textured peach of poor quality I was given. It tested 12 brix with a couple drops of clear juice as I normally do. I cut off a thin slice and mashed that down in the instrument. That gave a reading of 12 also as per picture.





So perhaps if one had a fig without seeds or if you mashed hard enough you could get a reading. The guy in the video didn't appear to mash his out that flat.

Steve
When I took the reading I just cut the seedless fig in half and lightly rubbed the center to the refractometer lens and got the Brix reading. 
Maybe you have point about the fig seeds interfering or is it possible that the fig wasn't ripe enough to have a juicy center just yet?

Fig was fully ripe and wrinkled up like pic in post #31. There is no juice. So I tried another fig. Wiping cut surface gave no reading but that could mean off scale, 35+ brix.

So I smeared center pulp on the instrument and crushed down really hard on the seeds, again no reading. So I took that and diluted about 50:50 with water. No attempt to get an exact 50:50 mixture. That read ~24 brix. I say approximately 24 brix because the reading was fuzzy, not a clear delineation between clear and blue when you look thru eyepiece. If reading is ballpark that also says brix is above scale, ~2 x ~24 = ~48 brix.

When I get more figs I'll try to get a more exact 50:50 mix of fig and water.

I think what I'll do when I get another fig as ripe as I like is dig out the fig pulp, the part that will mix easily with water, not the skin. Mix that two parts water to one part fig. Then strain that thru Agribon 19 to take out the seeds. That should get plenty of liquid and a good meter reading. I'm betting 48 brix is close to correct. Hard part may be making sure the water and fig pulp are fully mixed.

Will adding water dilute the Brix reading? Brix = % sucrose by mass (grams sucrose/100 g of solution)

I am going to repeat my experiment with another breba tomorrow (different variety) and see what happens.
The last fig was so juicy that it was no problem to get a liquid coating on the meter for a reading.

It would be interesting to hear from someone that makes fig wine and find out what Brix they get using a hydrometer for comparison.

If you dilute a 30 brix solution 2:1 with water you'll have a 10 brix solution. So fig diluted 2:1 with water that reads 15 brix means the fig was 45 brix.

A juicy fig is clearly more watery than mine and way lower in brix.

OK Understood!  Good luck with your testing.

Steve,

How did you get that relation?

For fruit juices, 1.0 degree Brix is denoted as 1.0% sugar by weight. This usually correlates well with perceived sweetness.
It seems that 2:1 solution should give you 15. I think the temperature at which the measurements are done is important, needs to be close to 20C

Steve you are growing pure candy, I am glad you are posting on this subject as I have wondered about it but couldn't be bothered to try it.  Hearing that you are expecting 48 brix is quiet impressive as I imagine if you are getting high brix on your fruits and not just figs means to me you are coaxing out a lot of flavours as well, the reason for my thinking on this is you are putting a lot of work into maximizing your fruit development and ripening so you are not just getting sugars but also all the other compounds into higher levels.  This brings me to ask, are you willing to share your secrets, I would really like to learn what I can do to better maximize things on my fruits and figs.

Pino,
Hope this doesn't get confusing as I was away.
I'm not Canadian. I'd love to live in the mountains of the PNW though. When I rode through there I fell in love. One of the most beautiful areas in the world (or of what I've seen anyway).
Both Bass and Harvey ship with phytosanitary certificates and both have excellent collections.

Pino and Steve,
The seeds or anything else solid - like a piece of skin will certainly throw off the reading even further.
Steve - where did you get the formula or info on dilution?

Hi Chivas. Steve's reading are in the stratosphere compared to what I'm seeing. wow

My meter says tests should be taken at 68 degrees f.

Steve I grow in pots and have the same problem -- I have to water every day. Oddly enough I started only watering the plants at the soil line (before I was "raining" the water down on them) and I have had, so far, much sweeter figs. As the sample sizes are so small and the varieties are not all the same I'm not sure if this will continue or has anything at all to do with the change in watering. It does decrease the amount of rust and that is probably a factor.

OK, here are my numbers.
These were done with an analog meter much like the one in Steve's pictures.

I cut the figs in half and rubbed the pulp on the meter after wetting it with 2 drops of distilled water. The tests were done at 67 to 71 degrees f.
My manual says it's very important to have a temperature as close to 68 f as possible.

I pointed the meter out my kitchen window. There are a couple readings where I pointed the meter toward a photographic light source as it was raining and the sun was not bright enough.

These numbers do not reflect what I perceived when I tasted them. I listed that order below.
Florea 27.5
Valley Negra 2.5
Conadria 3.0
Sal's Corleone 7.0
Vista 11.0
Saint Jerome 13.0
Saint Jerome (2nd tree) 26.0
Paradiso "Gene" 1.0
Bisirri Dark 28.0
Brooklyn Dark 5.0
Enrico 31.5
Peter's Honey 23.0
Brooklyn White 7.0
Brooklyn White (2nd tree) 25.0
Filacciano Bianco 23.5
Sicilian Red 17.5
Col de Dame Noir 10.0
Dauphine unknown 23.5
Camuna Small 14.0
Morena 29.5
Vicenza 2.5

The list according to my taste buds;
Brooklyn White
Filacciano Bianco 
Morena
Col de Dame Noir
Saint Jerome
Saint Jerome (2nd tree)
Vista
Peter's Honey
Brooklyn White (2nd tree)
Enrico
Vicenzo
Camuna Small
Bisirri Dark
Valley Negra
Conadria
Florea
Sal's Corleone
Brooklyn Dark
Paradiso "Gene"
Sicilian Red
Dauphine unknown

Obviously these represent absolutely nothing that's valid.

Just for fun:
Main crop figs

Florea 26.0
Ronde de Bordeaux 32+ (my meter stops at 32)
Lemon 15
Brown Turkey 8.0

Okay well as much as that was fun, the meter's manufacturer made it very clear that anything but 2 drops of clear, clean liquid without any solids will produce invalid and worthless results. I am still in touch with the manufacturer as they are trying to find one of their customers that has found a working solution to this dilemma. 

Pino,
The Lemon was really tasty. I'm really impressed with this fig. It's big (90 grams) and pretty (light greenish yellow) and solid enough to be handled. I think it would be a great fig for selling at farmer's markets.
The RdB continues to try and convince me it's the best fig I own. I have 3 large ones but one always ripens ahead of the others. Early ripening is a big plus in my collection.

really interesting instrument  Michael, and more interesting the outcome. Thanks for giving this information.

I have one, don't know the name, given to me by a friend,
laboratory instrument that extracts liquid from a sample using a vacuum.
I quarter the fig, scrape the meat out, leaving the skin behind.
Sample is placed in the unit, and liquid is extracted into a small plastic cylinder.

Before I had this unit,
I would quarter and scrape the figs,
then use metal micron mesh filters,
massage the pulp through the filters,
then I would leave the  sieved pulp sitting on
the finest micro screen placed on top of the electronic brix meter,
within a few minutes, it would produce liquid.

From my testing,
average is  10-16 brix
good  is  18-24
once you get above 25  its special.

Generally people that consider a 16 brix fig as "really good"
most likely have never tasted a higher brix variety.
Human taste is also effected by current emotional state,
surroundings, temperature and many other factors.

thx waynea

BJ,
hhhm do you know who made it?

Michael,
Thanks for letting me know about Bass and Harvey.  Your lemon fig is sounding better all the time!

Some of your readings were low were some of these not ripe?

BJ,
To me your procedure before you had the unit looks very promising and your readings seem consistent!  

Maybe a member who has lab experience knows what
this apparatus is called.

BJ,
Skin on or off?

I never use the skin of any fruit or vegetable I test.

You can also use a brix meter to monitor your plants.
You can do crude leaf analysis with brix meter.
Lets say you want to test the results of adding a soil amendment,
fertilizer or some other mineral or additive.
Take a leaf before you add anything,  mash up the leaf to extract a couple of drops,
get your brix reading.
Now add your amendment, give it the allotted time to start working,
then test a leaf again.
If the brix went up,  the plant is responding favorably to your treatment.

HJ,
Very interesting. thx.

This has been/is a real informative thread, I have learned a lot and really impressed with the procedures and different instruments, that's what this forum is all about, thanks all.

I did a test on Strawberry Verte and grapes to see if diluting the fruit pulp with water would provide the clear liquid needed to allow brix measurement.

Grapes were my control. Cut 4 berries in half and measured brix on one half of each berry. Result was an average brix of 24.6. On the other half of each berry, skin was removed and 16 g water was added to 8 g of berries. This was mashed up and left in fridge overnight to equilibrate. That juice was strained thru Agribon 19 fabric and tested 8.8 brix. Since volume was 3 times original berries, 3 x 8.8 = 26.4 brix.  7% difference is within measurement error as scale used only reads to whole grams.

For the fig, 10 g pulp was extracted from a 21 g SV. 20 g water added, mashed up, and left in fridge just like the grapes. Brix of resulting clear liquid tested 13.4. Taking 3 x 13.4 = 40.2 brix.

I think 40.2 is a very reasonable brix number for a shriveled up fig. The upper limit of brix for a non dehydrated fruit is near 30. Plants can't concentrate liquid in there cells higher than that. Many of my fruits approach that as an upper limit. The SV fig would be near 30 when it goes limp but is boosted to 40 by dehydration.

As per previous post I tested my 2nd breba fig. 

I realize this is not a comprehensive measurement as Steve post explains. 
However there may be some merit to this simple Brix reading obtained by just wiping the overripe, juicy but transparent fig nectar unto the lens of the refractometer and getting a reading.   When the main crop finally gets here and I have lots of figs to play with I will try Steve's method to get the true Brix of all the fig parts. 

This reading just measures the Brix of the juice(fig nectar) not the pulp and skin...

The photo showed the breba hanging nice with it's 6 other siblings (very promising for a 3yr old fig tree). 


 

The fig turned out to be overripe and juicy , skin was still chewy the rest melted in your mouth, no seed crunch, mildly sweet and jammy with some berry tones.  It was OK maybe a 7.


The refractometer Brix reading: 21 
Not as sweet as it normally would be since overall we have had a cool wet summer so far.