Which citrus cultivars have the highest brix? Break it down into oranges, mandarins, hybrids, etc. if you can.

I'm looking for a recommendation Sunset zone 24, coastal so. Cal. Thanks for any advice.

I prefer SWEET

As far as I know, the Xie Shan (pronounced SHE Shan) Satsuma produces the highest sugar to acid ratio of any citrus, with a sugar to acid ratio as high as 20:1. I presently have two Xie Shan trees, really great fruit. - Millet (790-)

I'm not sure what the goal is, but realize that high ratio and high brix are not the same thing. Ratio is percent sugar divided by percent acid (expressed as citric), so if the acid number is small enough, you can get a very high ratio without much sugar actually being present. Parson Brown oranges often do that -- ratio off the chart, but they are just bland and watery.

Of the oranges, generally the later they mature, the more brix they will produce per unit weight of oranges, but those late maturers also tend to bear less fruit than the earlier kinds. So among oranges, I'd expect 'Valencia' on a high quality rootstock (Sour Orange, Poncirus) to have some of the highest brix achievable.

Surprising. I have alway thought Navels tasted mush sweeter then Valencia. In fact I dug up my 3 year old Valencia about a month ago and added it to the compost pile, and replaced it with a different variety. Xie Shan, ratio or not, is an exceptional fruit (in my humble opinion) and very sweet, that is why I have planted two Xie Shan trees. Originally, growing Xie Shan came as a suggestion from Bonnie Childers. . However, I fully realize taste is very subjective from person to person. - Millet (788-)

Exactly! Human taste perception is not based on brix alone, but on a combination of brix, total acid, and ratio of the two. Many years ago (50s??) Pritchet researched that subject with orange juice, and created the "Pritchet tongue," a bizarre looking graph that looks like an amateurly drawn tongue on the paper -- taste-testers found juices that fell within the figure of the tongue to be pleasant and desirable, whereas juices that fell outside the tongue in any direction were not pleasant. Low-brix, high-ratio juice can taste quite sweet. But the addition of the acid gives perceived strength to the flavor. Since 'Valencia' is quite a high-acid variety, it takes a lot of brix to bring its ratio high.

So that's why I started out with stating that I was not sure of the goal here -- is it really high brix, per se, or is it sweetness of flavor?

Based on Pritchet's tongue, the Florida standards for orange maturity require a minimum of 0.4% acid, a minimum brix level (which varies by date), and a minimum ratio (based on actual brix level measured), as well as a minimum juice content of 4.5 gallons per 90 lb box. A fruit is "mature" only if it meets all of those requirements. Navels often fail to meet the juice requirement even when they're passing in all other ways, so inspectors will generally let them pass, as long as they are perceived to taste good.

Looking at the Citrus Colonal Protection Program's variety list I see that Ponkan shows the highest soluble solid content of 13.9. - Millet (787-)