Brix over time

[Frosti]

Hey everyone,

this season I got myself a refractometer to more accurately select the plant with the sweetest fruits for my current breeding line, and I thought some of you might find my results interesting, so here they are ...

A quick background:
This is a multiflora line with the original goal of a dwarf multiflora plant, but the best tasting plant last year turned out to be a bit of an oddball. Not really a dwarf, but also not quite tall enough to not call it a dwarf. Anyway, the offspring of this plant also turned out to be very compact and healthy but since I crammed 2 plants in each 40L pot and I pruned them to a single main stem they eventually grew to a normal height. There are 18 plants in 9 pots, all next to each other at the same location. This is what my jungle looks like today, after neglecting it for quite some time already:

jungle.jpg

These are my brix measurements over the last 4-5 weeks:

brix_1-23-F3_20240907.png

I did not expect them to fluctuate this much. I also think the brix took a downward turn when the weather got too hot for tomatoes (about 30°C).
Of my 18 candidates only three are still in the race for next season. The plant with the highest average brix of 12.5 is 5-24. This is also the plant with the highest floor with a minimum brix of 11.9. Its hightest peak was at 13.4, while 18-24 peaked at 14.0, but also plummeted all the way down to 10.2 ...

just for comparison's sake, one of my all-time favorite cherries is "Mexican Honey" which had a brix of 10.5 this season, while "Großes Birnchen", which in all likelyhood is "Yellow Submarine", reached 11.1.

All three remaining contenders have very good taste, so which one would you choose?

[Doffer]

I have noticed that the Brix can also vary greatly per fruit. For example, I had a beef plant that had fruits with Brix 5 that tasted normal and fruits with Brix 8 that were super tasty.

[bower]

Love that sweetness jungle! I've never measured brix, but I do gravitate towards sweeter fruit. Sweetness varies depending on ripeness, which can be difficult to judge. Sweetness may also be affected by water uptake, as many have commented over the years, overwatered plants don't produce tasty fruit. So a period of more rain, for example, could cause variance. And as you mentioned, heat has an effect as well, on ripening and taste development, as does cold.
Since you asked, I would choose the plant with the least variance in brix, that is your red line, to grow forward, given that all have equally excellent taste. But I would save seeds from all of the contenders just in case!
A plant that does best at maintaining its taste in variable conditions, is going to be the top selection IMO, unless it has some other defect in production or quality that can't be eliminated by selection at the next round.

[Frosti]

Love that sweetness jungle! I've never measured brix, but I do gravitate towards sweeter fruit. Sweetness varies depending on ripeness, which can be difficult to judge. Sweetness may also be affected by water uptake, as many have commented over the years, overwatered plants don't produce tasty fruit. So a period of more rain, for example, could cause variance. And as you mentioned, heat has an effect as well, on ripening and taste development, as does cold.
Since you asked, I would choose the plant with the least variance in brix, that is your red line, to grow forward, given that all have equally excellent taste. But I would save seeds from all of the contenders just in case!
A plant that does best at maintaining its taste in variable conditions, is going to be the top selection IMO, unless it has some other defect in production or quality that can't be eliminated by selection at the next round.

This is my current reasoning as well. I took care to always water the plants equally. Regarding the ripeness, this was another revelation for me. In the past I always thought overripe fruits were the sweetest while the texture got worse. Now I realize that peak sweetness and flavor is present when the fruits are ripe but not overripe.

I'll keep measuring the brix up until the end to see how the contenders fare in all conditions.

[Frosti]

I have noticed that the Brix can also vary greatly per fruit. For example, I had a beef plant that had fruits with Brix 5 that tasted normal and fruits with Brix 8 that were super tasty.

While I did notice some variance between the fruits on the same plant, it was mostly +- 0.5 brix iirc. This is why I chose to measure quite often, which is easier done with cherries than beefstakes of course.

[Frosti]

This is my full dataset:

brix_1-23-F3_20241231.png

Some of my plants made a noteworthy comeback at the end of the growing season (both have yellow fruits), but in the end they could not change the overall outcome.

The final daily average brix for 5-24 (winner) was 12.35 and for 18-24 (runner up) it was 12.11.

I decided to give both a chance next year, so I'll plant 9 offspring each.

To be continued in 2025!

[karstopography]

I need to get a brix meter. Just for fun. I understand cherry tomatoes tend to rule the brix battles. Brix isn’t the end all and be all of judging tomatoes, but it’s a hard point measure.

[Frosti]

I need to get a brix meter. Just for fun. I understand cherry tomatoes tend to rule the brix battles. Brix isn’t the end all and be all of judging tomatoes, but it’s a hard point measure.

Exactly. I do however heavily favor sweet tomatoes, so this measurement is really useful to me.

Regarding the battle between cherries and other tomatoes: There was one super sweet beefstake this season that could battle with the cherries ... Kellogg's Breakfast with an amazing brix of 9.5. Usually the larger tomatoes seem to be down at 5-6.

[karstopography]

I need to get a brix meter. Just for fun. I understand cherry tomatoes tend to rule the brix battles. Brix isn’t the end all and be all of judging tomatoes, but it’s a hard point measure.

Exactly. I do however heavily favor sweet tomatoes, so this measurement is really useful to me.

Regarding the battle between cherries and other tomatoes: There was one super sweet beefstake this season that could battle with the cherries ... Kellogg's Breakfast with an amazing brix of 9.5. Usually the larger tomatoes seem to be down at 5-6.

The plan is to grow KBX this year, a derivative of Kellogg’s Breakfast.

The problem I perceive with cherry tomatoes is the texture.

I’ll continue to search out those tomatoes that check the texture box, but Brix readings would interesting to know about regarding my favorite tomatoes.

[Uncle_Feist]

I planted my crop of an F10 determinate for canners and juicers this past summer to mature in the peak harvest window to maximize sugars and soluble solids in the final product. The crop was also planted in a high tunnel to limit foliar disease and they were also kept well fed.

Harvest and processing of fully colored fruit began weekly on Aug.19th and continued through mid September at which point I pulled the plants to utilize the space for fall/winter crops.

Four, 15 gallon batches of juice were made on almost weekly intervals and each batch was checked with the refractometer. The first batch in August gave a reading of 8.5 brix, each successive batch steadily climbed the scale and reached 10 and 11 brix just before the plants were removed. This kinda caught me off guard as I expected the exact opposite heading into late September.

[Frosti]

I planted my crop of an F10 determinate for canners and juicers this past summer to mature in the peak harvest window to maximize sugars and soluble solids in the final product. The crop was also planted in a high tunnel to limit foliar disease and they were also kept well fed.

Harvest and processing of fully colored fruit began weekly on Aug.19th and continued through mid September at which point I pulled the plants to utilize the space for fall/winter crops.

Four, 15 gallon batches of juice were made on almost weekly intervals and each batch was checked with the refractometer. The first batch in August gave a reading of 8.5 brix, each successive batch steadily climbed the scale and reached 10 and 11 brix just before the plants were removed. This kinda caught me off guard as I expected the exact opposite heading into late September.

Thanks for your input! A brix of 8.5 - 11 is super good for canning tomatoes. What exactly was the variety? I see you said F10, is this a variety you bred yourself?

[MrBig46]

I'm curious how you measure Brix. Do you take the juice directly from the tomato or do you process the whole tomato somehow, strain the juice and then use it for measurement?
Vladimír

[Frosti]

I'm curious how you measure Brix. Do you take the juice directly from the tomato or do you process the whole tomato somehow, strain the juice and then use it for measurement?
Vladimír

I'm still working on the optimal method of measuring brix, but this is how I currently do it:

1. Select fruits at peak ripeness (letting them go to overripeness results in a noticeable decline in brix).
2. Select fruits of average size, if possible
3. Preferably select up to three fruits and average the results. No cheating! If the last one is less sweet then that's the way it is!
4. Cut off the very top or the very bottom, so that a very small area of fruit flesh is exposed
5. Squeeze very gently
6. Press the fruit a few times against the glass plate of the refractometer to cover the entire area in juice. If you're careful no seeds will end up on the glass plate.
7. Close the plastic lid, open it again, and close it again to spread the juice evenly

I don't blend the tomatoes or process them in any way. The measured brix is from the raw fruit juices.

Do you guys do it differently?

[Uncle_Feist]

Thanks for your input! A brix of 8.5 - 11 is super good for canning tomatoes. What exactly was the variety? I see you said F10, is this a variety you bred yourself?

You are very welcome, @Frosti and thanks!

My F10 was a red, F1 fresh market determinate called Fabulous. I loved it and grew it for many years for market and discovered along the way it was also a great canner. I heard it was pulled off the market by the supplier because their distributor was bought out by Monsanto sometime in the early 2000's, I don't recall the exact year.

Anyhow..
I've been messing with it off and on since. Sometimes I will grow a generation for several years, then decide that I will make selections again. They are nowhere near stabilized at F10, but are still tasty, productive and most importantly, make a great juicer!

This is them on the left July 21st last summer.

This is the first partial picking the evening of August 19th, and I finished up the next morning with an additional 3 buckets of fruit.

Here's the first 60 quart stockpot of juice just before going into jars.

And then in jars.

[Uncle_Feist]

I find that brix readings are somewhat higher in processed fruit than in raw. The explanation I understand is cell walls break down with heat thus allowing more sugars to be released and absorbed into the surrounding liquid.

[Frosti]

Thanks for your input! A brix of 8.5 - 11 is super good for canning tomatoes. What exactly was the variety? I see you said F10, is this a variety you bred yourself?

You are very welcome, @Frosti and thanks!

My F10 was a red, F1 fresh market determinate called Fabulous. I loved it and grew it for many years for market and discovered along the way it was also a great canner. I heard it was pulled off the market by the supplier because their distributor was bought out by Monsanto sometime in the early 2000's, I don't recall the exact year.

Anyhow..
I've been messing with it off and on since. Sometimes I will grow a generation for several years, then decide that I will make selections again. They are nowhere near stabilized at F10, but are still tasty, productive and most importantly, make a great juicer!

This is them on the left July 21st last summer.

This is the first partial picking the evening of August 19th, and I finished up the next morning with an additional 3 buckets of fruit.

Here's the first 60 quart stockpot of juice just before going into jars.

And then in jars.

Wow, those look really delicious! Both raw and in the sauce, I love the color. Since I always mix multiple varieties my sauce color is a lot lighter, more orange than red.

So you measure the brix after cooking the tomatoes? Do you add sugar / garlic / oil prior to your brix measurements?

I'm not sure what effect this has on the brix, since I never have enough plants of the same variety to make a sauce consisting of only one variety. But you could meassure the brix of some of your tomatoes just before processing and after in the coming season. I'd be interested in the result!

[Uncle_Feist]

Wow, those look really delicious! Both raw and in the sauce, I love the color. Since I always mix multiple varieties my sauce color is a lot lighter, more orange than red.

So you measure the brix after cooking the tomatoes? Do you add sugar / garlic / oil prior to your brix measurements?

I'm not sure what effect this has on the brix, since I never have enough plants of the same variety to make a sauce consisting of only one variety. But you could meassure the brix of some of your tomatoes just before processing and after in the coming season. I'd be interested in the result!

I measured the brix just after the juice came to a boil, not reduced and nothing added. I'll try to remember to get some raw readings next year and post back here. Thanks!

[rdback]

What a nice looking tomato and a beautiful looking sauce, @Uncle_Feist! If you by chance participate in MMMM, I hope you send in some seeds, even as "Experimental". I'd love to give this one a grow.

[Frosti]

What a nice looking tomato and a beautiful looking sauce, @Uncle_Feist! If you by chance participate in MMMM, I hope you send in some seeds, even as "Experimental". I'd love to give this one a grow.

@Uncle_Feist same here.

[MrBig46]

I'll come back to measuring Brix. Of course, measuring Brix in cherry or slicers is easier than measuring Brix in beefsteaks. I think that if a sample of tomato pulp can be frozen in the freezer, the Brix will not change (all enzymatic processes, etc. will stop). The pulp will be torn apart by the freeze, everything will be strained and can be measured. It's not a problem to verify this.
Vladimír