What brix really means

This spring I’m noticing my brix readings not exactly coinciding with how much I enjoy my peaches. I just ate a Goldust peach that was plenty sweet enough and gushing with juice with a fibrous, meaty texture you expect from later ripening, quality peaches. Way too much rain made sure that the pit was so badly split that it deformed the shape of the peach, widening it considerably.

Anyway the brix reading was only at 10 which is quite a bit lower than readings I was getting from Desiree peaches that weren’t as good to me. Later peaches will probably average between 12 and 13 when picked a day from perfect ripeness.

The thing is that the peach was extremely juicy, in the manner J. plums are juicy compared to E. plums. E plums consistently get higher brix readings so I think that extra juiciness brings down brix percentage.

Maybe this is an obvious correlation to anyone with a lot of experience evaluating stone fruit (fruitnut?). Until a couple years ago, I just judged the fruit by how much I liked it, but the refractometer brings another dimension that is less subjective to the discussion and descriptions.

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I’ve noticed that for some fruits, a brix of 10-12 is considered sweet but for others the preferred sweetness is in the 16-19 range.

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Brix is the measurement of dried solids, including non sugars, but mostly sugars. Fruit contains many sugars, mostly fructose, but also others. All are read by the meter, but sweetness by taste will vary by composition of sugars. Some fruits contain Erythritol. a sugar alcohol. Which I’ll be using to combat SWD. Waiting for 5 pounds to get here in the meantime dry spraying DE.
I like the idea of filling my sprayer with Erythritol and licking my fingers clean.

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The population in your area is not good.

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I can’t see that well these days and when I’m spotting SWD around my blackberries, I sprayed the DE ASAP. the Erythritol which we talked about here. Will be here tomorrow.
Darn things are thick this year. i still eat the fruit. If you put it in the fridge they crawl out, but I eat them while I’m picking too. It has stopped me from giving away fruit.Also fruit softens before ripe, some cultivar do, others do not. I tried to attract humming birds too, but have yet to see one. I’ll keep trying that too.
I’m going on vacation and will be going in a couple weeks. I’ll spray real insecticides before I leave since I won’t be harvesting the fruit produced while gone.

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You mean dissolved solids.

How much Erythritol are you using per gallon? If my calculations are correct from the studies, it looks like you should use 1-2 lbs per gallon for best results which gets expensive if you are spraying. 1 lb of Truvia is about $7 around here. Maybe not so expensive if baiting.

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:cry:

yes, I meant to say dried solids dissolved. to distinguish between wet solids. .

Well waiting on the product, In their trial at USDA they dissolved 1/2lb into a gallon of water and sprayed it on the berries 1 time / week. I’m not paying that much 5 bucks a pound.
So $2.50 a spray I figure 2-3 sprays should be plenty. It takes 3 days to kill adults. Although they stop laying eggs right away. I would think you could not dissolve 2 pounds in a gallon, it would fall out of solution. I know that would be true for sugar as I make humming bird food all the time.

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I’m considering upgrading my meter from the handheld electronic type to a “lab in a box” – i.e. fruit sample goes in, lots of data comes out. Anyone have experience with these?

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Looking forward to your results.

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Yeah nothing is working great, so have to try something.

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OK, so I just enjoyed a nearly perfect (to me) silver gem nectarine. It only had a brix reading of 12-13 so here’s what I think. Brix is not an absolute measure of sweetness at all because of the issue of relative wetness. More water does not necessarily dilute the sense of sweetness so a drier fruit needs higher brix to taste as sweet as a wetter one. The nectarine I just ate was wetter than a Shiro plum!

The other issue is acid, of course, as more sugar should be required to detect the same level of sweetness, but this just doesn’t add up to my palate. Silver Gem has typical nectarine acidity (at least before the breeders started shooting for low-acid), but even with that acid zing the sugar showed through.

Waddaya think FN?

Do you have an example of a “lab in a box”?

You could have a point. A 14 brix watermelon is very sweet. I guess what I’d disagree with is the idea that sweeter fruit isn’t generally more flavorful. Sweeter usually tastes better and not just sweeter. There are exceptions. Some fruit just have no flavor regardless of how sweet it is. That perception of flavor is likely a personal experience.

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Also things like extreme bitterness and extreme sourness can make sweetness less obvious.

I have seen them in the office of a few growers (wine grapes, citrus) and apparently there’s one at county Ag. I thought Atago made such a device but their meters are generally single task.

Actually this concept is what led to bland tomatoes, peaches, etc. Back in the 50’s distributors and markets wanted fruit with longer shelf life, so fruits were bred for this characteristic. But in retrospect it was the proteins that were bred out those fruits along with structure that led to rotting – and further it is the proteins that carry much of the flavor (there’s a number of papers on the subject). So breeders such as Zaeger have gotten smarter and now we have flavorful fruits such as Pluots that also have a long shelf life.

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With tomatoes, part of the problem is breeding to harvest all toms at the same time. This vastly reduces the leaf to tomato ratio as leaves of indeterminate toms keep growing as new fruit forms. To bad no one has bred an indeterminate peach that forms new peaches all season long served by new leaves. Of course I can see how this would be almost impossible, but mulberries can do this.

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Yes.

Notice the evolutionary history of Solanum vs. Prunus. The Solanum genus (esp. tomatoes) evolved in a tropical environment where they are an evergreen plant. The typical lifespan of tomato plants in those areas is 7 years. Here in mild areas of San Diego county it can be 2-3 years. But deciduous Prunus – these evolved in 4-season climates. The path to evergreen there is much more difficult.

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