Thursday, March 11, 2010

Part V: Is High Brix Enough?

Part V: Is High Brix Enough?

by Michael Astera

edited March 14, 2010

Finally the concept of measuring produce quality in degrees Brix (*Brix) is getting some legs. People like the idea of being able to determine quality in their food. Measuring Brix also has some fun geek-appeal, e.g. carrying a scientific instrument in your purse or pocket that can graphically show the difference between a sweet orange and one not worth tasting. When Chefs de Cuisine start meeting food deliveries at the back door with a refractometer in hand, the game changes. When the shopper at the local fruit stand pulls out a refractometer, the game really changes. It's no longer just about having pretty produce. Two green peppers may look identically perfect, but the pepper that "Brixes" 12 is likely going to taste like a green pepper; the one that Brixes 4 is only going to look like the real thing.

Does that mean that a crop that has a high reading in *Brix is high in nutrients? Probably, but which nutrients and in what form? Are those nutrients in the best proportion and amounts for human and animal health? Maybe, maybe not.

The Brix scale was invented to measure sugar content, and is scaled against the equivalent in pure sucrose dissolved in pure water, i.e. if the solution is 32% pure sucrose by weight, it reads 32*Brix. Except: A refractometer measures all dissolved solids that bend incoming light. Caribbean sea water from the beach out front measures 4.8*Brix.

What do other common items measure in *Brix?

Without exceeding my normal science budget, I managed to put together the following "Laboratory Experiment" yesterday:

Laboratory Experiment #1

The boxy thing at the back of the scene is an old worn out car battery. The sulfuric acid in its cells measured 13.2*Brix.

Lined up in front of it, L to R, are a couple of bags of commercial fertilizer, a glass espresso cup with silver spoon, a cake of papelon raw sugar, a 0-32*Brix refractometer, an orange and a banana. Behind, R to L, a box of baking soda, bottle of soy sauce, jar of salt, vanilla extract, refined sugar, and a bottle of Old Tom gin. On top of the battery, L to R, toilet bowl cleaner, phosphoric acid, and ceramic tile cleaner with ammonia.

I spent the late morning and early afternoon taking a *Brix reading of everything in the photo.

The dry items were mixed to saturation with local bottled water (0*Brix) in the glass espresso cup, then sucked up with a plastic pipette and a few drops of the solution were placed on the refractometer prism.

The household chemicals and other liquids were taken up directly from their containers using the suction pipette.

All utensils and the refractometer were carefully washed and dried between tests.

The refractometer was then held up to a good light source (the sky) and the reading in *Brix was noted.
Here are the results:

*Brix of Common Items:
Results of Laboratory Experiment #1
Item Tested
Household Chemicals

Sulfuric acid from old car battery

"MAS" toilet bowl cleaner
(dilute hydrochloric acid + wetting agent)

Laundry bar soap for baby clothes
(not pictured, sorry)

"MAS" Ceramic tile cleaner w/ammonia

Baking soda (Sodium bicarbonate)
(S = saturated solution in H2O)

Refined iodized table salt
White sugar (sucrose)
Raw sugar (papelon)
Vanilla extract, pure

Distilled white vinegar, 5% acetic acid

Orange, local juicing type

Pineapple, commercial

Banana, backyard local

Aloe Vera sap, fresh

Gin "Old Tom" 90 proof

Fertilizer Chamicals

Urea (ammonium carbamate) 46-0-0
High Phos. water soluble (10-40-10?)
Ortho Phosphoric Acid ~50% P
1:1 H2O
1:2 H2O

It is clear that the refractometer measures a lot more than sugars; these results indicate that acids and alkalies raise the brix reading, as does alcohol content. Pure chemical fertilizers also raise the Brix.

It is safe enough to assume that high-Brix produce will have more dissolved solids, but which solids?

Even if we just look at the sugars there can be a lot of variation in nutritional quality. What are the sugars likely to be in hybrid super-sweet corn? Simple sugars. High fructose corn sugar is about as simple as one can get.

Simple sugars metabolize quickly, give a big sugar rush, and cause an insulin spike; they are hyperglycemic. Long chain complex sugars, aka polysaccharides, metabolize slowly; they have a low glycemic index. The longer and more complex the saccharide, the slower it will be digested or metabolized.

Extremely long chain poly-saccharides are called muco-polysaccharides because they have mucus-like slimy qualities. Examples can be found in the sap of aloe vera and other succulents, comfrey, and slippery elm bark.

Note that aloe vera, comfrey, and slippery elm are all well-known healing plants. It is largely their muco-polysaccharide long-chain sugars that give them their healing qualities. These "sugar molecules" can have 30,000 or more individual sugar molecules "chained together", versus only two sugar molecules, glucose and fructose, that are joined together in refined sucrose. Sucrose burns fast and hot; long chain sugars burn slow and steady. It has been shown that while simple sugars cause or aggravate diabetes, long-chain polysaccharides heal the pancreas and counter diabetes.

The refractometer, unfortunately, can't tell tell us whether the sugars are simple or complex, and it's not likely that we are going to be willing to pay for the elaborate chemistry needed to sort them out, so what to do?

As has been mentioned before, one can get a plant tissue test for minerals; essentially the same thing as a soil test, but measuring the mineral elements that the plant has taken in.

One thing we know about complex micro-biological structures like polysaccharides and amino acids is that they require mineral catalysts in order to be formed or made. Phosphorus is necessary for all complex sugar formation. Zinc is known to be necessary for over three hundred enzymatic functions and likely plays a part in sugar complexity too. Calcium, Magnesium, Potassium, Boron, Iron, Manganese, and Copper are all essential for both plant and animal health. A crop that is deficient or unbalanced in any of them will not be truly healthy, nor will it make truly healthy food, despite cosmetic appearances.

At the present time most commercial and home garden agriculture is focused on high Nitrogen and Potassium fertilization. Mammals such as humans use around three times as much Phosphorus P as Potassium K, and over four times as much Calcium Ca as K. So why are we fertilizing with Potassium and Nitrogen?

Because they are common, easy, reasonably cheap, and give a good growth response, i.e. high yield. No real consideration is given to the nutritional quality of what is grown. How many tons per acre is the standard. We have already gone over all of that; just getting more detailed here.

Warning: Chemistry ahead!! (but stay with me please)

Back in the 1940s, Firman Bear and crew working at Rutgers U in New Jersey observed that alfalfa (lucerne) and other crops took in a fixed total sum of the cation (cat-eye-on) elements Ca++, Mg++, K+, and Na+. Those +plus signs indicate the charge on the different ions. Cations have a + positive charge, anions (an-eye-ons) have a - negative charge. Living things balance + and - in their body fluids to regulate pH, acidity or alkalinity. Plants and animals use Ca++, Mg++, K+ and Na+ to raise the pH and make the biology more Alkaline; they use the anion - elements NO3- (nitrate), SO4-- sulfate, and Cl- Chlorine, along with carbonic acid, to lower pH and make their fluids more Acid.

Note that Ca++ has two positives, K+ only has one. Cl- has one negative, SO4-- has two. To achieve a stable compound with SO4--'s two negatives would take one Ca++ or two K+'s.

The sum of the negative and positive charges equals the pH. A plant can take in 200 parts of Ca++ Calcium to balance its pH, if Calcium is freely available, or it can take in 400 parts of K+ Potassium, or 400 parts of Na+ Sodium to do the same job.

The question becomes, what do we want in our food? Once a plant has the minimal requirements of an element for its physiological processes, enough Ca, Mg, and K to function, it doesn't seem to care which "extra" cations it uses to balance its pH; it will use whatever is freely available. If that is Na Sodium, that is what it will use. If K Potassium is abundant while Mg Magnesium is scarce, the plant will pack on the K and be Mg deficient.

The same rule seems to apply to anion balance. If NO3 nitrate and Cl Chlorine are freely available while SO4 sulfate is rare, the plant will load up with what is easy to find and will be deficient in Sulfur. Sulfur is needed to synthesize at least two essential amino acids. Low Sulfur means a lack of complete protein.

Why does this matter? Because it seems that when plants take in lots of Potassium they are only able to make simple sugars, and when they take in lots of Nitrogen they only make simple amino acids and proteins.

Lacking the necessary catalysts such as Zinc and Phosphorus, lacking Calcium, Magnesium, or Sulfur, the plants can only produce simple and incomplete nutrients.

By focusing on the Nitrogen and Potassium levels of our soils we sacrifice nutritional completeness in order to achieve high yield. That sort of reasoning may work if one is growing fiber such as cotton; it does not work for growing good food.

Again the question, if high Brix is the sole goal, is it possible to grow high-Brix crops in depleted soils with chemical fertilizers like N and K? The super-sweet hybrid corn proves it can be done. If a high Brix reading is going to be where the money is, one can expect to see heads of broccoli and cabbage that Brix 12* yet have no more complete nutrients than the sweet corn.

That is why we need proof of mineral content via a laboratory plant tissue test. If that test shows a well balanced abundance of essential minerals, chances are the saccharides and the amino acids/proteins will be complete and varied, simply because the plants had everything they needed to grow to their fullest potential of flavor, aroma, and real food value.

If the crop is high in Potassium and/or Nitrogen, but low in Calcium, Magnesium, Phosphorus, and essential trace elements, we can safely assume that it is not going to be excellent food, regardless of its Brix reading.

For lots more Info on Soil Minerals, to peruse our selection of organic approved amendments and fertilizers, or to read Chapter 1 of Michael Astera's The Ideal Soil Handbook, please check out the website that's all about soil minerals,


Farmer Allan said...

A much needed discussion! Good job, as usual, Michael -Allan

Kris Johnson said...

That's why I think it's important to consider the other readily observable factors associated with high quality - taste, keeping quality, healthy growth, and pest resistance. Those complex organic molecules the plant makes when a good plentiful supply of balanced minerals is available give wonderful flavor. Some folks who've had lots of experience say they can tell high brix simply by tasting.

Johnny said...

EXCELLENT! A leap into a higher level of thinking/research. Too bad most people don't even get the importance of basic Brix.


Anonymous said...

I was covering BRIX with my brother-in-law in the Philippines the past few weeks. He works with the department of Forestry (linked to agriculture) & this is going to spread to the farmers there like wildfire.

Also covering soil fertility and many other issues addressed here and elsewhere.

Great site - keep up the ground-breaking work.


Anonymous said...

Astera I don't know what in the heck you are talking about but I do throw everything I can get my hands on my garden. Manure, calcium, blood mix, lime and garbage. It is hard to get the soil up to par in Florida as it is mostly sand.

Last year the squash and tomatoes had some kind of fungus. Only the cherry tomatoes seemed immune to it.

m_astera said...

What I'm talking about is getting the soil minerals tested and measured by a lab, so one knows exactly what is there. Then they can add the right amount of the amendments that are needed, instead of "everything" which can mean adding things you already have too much of and throwing things further out of balance.

Plants get diseases for the same reason animals and people do, usually malnutrition that weakens the immune system.

Hubert Karreman, VMD said...

Thank you for presenting a balanced approach. I have heard about Brix from farmers and how wonderful it is. I see its value for sure but i also like to temper all out belief with a rational balance i.e. your showing the brix values of various household items. To most of the people i know, Brix is sugar and that is that. Thanks for reminding folks that it the dissolved solids in solution is what is read on a refractometer. I've used refractometers for total protein of serum, and that can be about 6-8. That is not "Brix" although there may be sugars in there. The point being, like you said, its not just about sugar but also minerals being taken up. I agree fully with the calcium, sulfur and boron that you mention. I have heard the same things from Gary Zimmer and Jerry Brunetti (both of who I'm a big fan), they are also 'students' of the Albrecht method.
As I start checking Brix for farmers, I thought the end of the afternoon was the best time to allow for the photosynthetic activity to have peaked (and thus sugar formation), but you mention at about 2 hours after the sun comes up. Can you explain?

Hubert Karreman, VMD

m_astera said...

Hello Doc Hubert-

Thanks for the kind words. I don't remember writing that 2 hours after sunrise was the best time to check Brix; can you point me to it please?

Good info about total protein in serum; that's probably a lot of what is being measured when people use a refractometer to check the Brix of milk.

I think you would also be interested in Barb Lee's blog, Albrecht's Animals:

Barb has done some great things with her leached out pastures in Oregon and gets the mineral message across well.

She and I have been coming to the idea that the main problem in feed and animal health is high Potassium, especially the use of Potassium chloride fertilizers. These days I'm thinking that a pasture or hayfield should ideally have K saturation between 2 and 3% of CEC, no higher or one is looking for trouble.

Hubert Karreman, VMD said...

Hi Michael,
Without doubt, potassium is well known to cause problems dairy cows. It should be kept at less than 2% of the feed ration, especially for dry cows to prevent milk fever (hypocalcemia). Potassium chloride is definitely not a good source K - very detrimental.
Sorry about tagging you with reading the brix at 2 hours after sunrise, must have been another site i was reading last night on brix also. It just seems to make sense to check it in later afternoon after the photosynthesis has been happening. Is there a chart of common brix values for clover, alfalfa, orchard grass, timothy, sorghum-sudan grass, triticale, etc.?
Hubert Karreman, VMD

m_astera said...

Doc K-

As far as I know, the only Brix charts are those that are found on Rex Harrill's site and elsewhere on the web.

Part of the High Brix Project is to gather that sort of data. We have at least three participants who are working with pastures, but the info is just starting to come in.

Of the two reports I've gotten so far, both early spring in the Pacific NW, forage in an untreated pasture measured 0* Brix. That from a pasture that has had regular soil tests and minerals added for a few years measured 5* Brix.

I agree that mid-afternoon of a warm day would give the highest Brix readings.

I expect some problems and resistance from those people keeping horses with metabolic disease problems when we start promoting high Brix feed. Right now people are soaking hay to try to lower the Brix before they feed it to their horses.

Something is wrong with that picture.


Cat said...

I have been told that the more "fuzzy" the brix reading line is, the more minerals and complex sugars are in the sample. Do you agree with this notion?

m_astera said...

Hi Cat-

The way I first heard it, a fuzzy line on the refractometer meant high Calcium. A friend did a few tests with that idea last year, to see if other things would make the line fuzzy. As I recall she tried Epsom salts in water and some sort of Potassium supplement. Even at saturation levels the line was still crisp and clear. So maybe it is just Calcium that makes the line fuzzy.

More research is needed! (as always)


a GrebBear said...

Hey m_astera,
Have you seen this before ??

ORMUS or m-state elements

This is no bullshit ... and the reason my rosemary plant looks like a Dr. Seuss knock off. The smell, texture and intense flavor, would convince the most skeptical of minds. ))

Anyways, just in the process of making a new 'wet trap', see: super concentrator ))

a GrebBear

Peace Love Light Truth
(- ;
; -)

MSc said...

When you started talking about mineral element cations and anions affecting pH, thats when I knew for sure that you have no idea what you're talking about. Perhaps you mean eltrochemical potential.

Also generally farmers apply fertilizer, mostly minerals mined and refined from the earth, to obtain maximum economic yield. Note the word economic and not just maximum. This can only be accomplished with balanced plant nutrition. What a plant needs is different to what a homo sapiens needs. A crop is the most productive and ultimately nutritious (to humans) when you balance its requirements optimally. PS. pH is a logorithmic measure of available H+ ions in solution and is not at all related to the amount of ionic mineral elements in solution.

m_astera said...

Hmmm. Is this supposed to be a joke or what?

Try reading this essay and see if things become a little more clear to you:

Michael Astera

陳雲惠 said...

IS VERY GOOD..............................

elhnad said...

since you've read the rex harril charts, i don't understand why you didn't mention that each vege/fruit has its own brix levels so (the following's a hypothetical example with made up numbers) to compare a "sweet" corn hybrid that is on its low end of the brix value but still has say a brix of 12 to a squash that is on the high end of its brix value of say 14 doesn't really mean much. maybe i read too fast but your article makes it seem that you can compare across foods.

Second, i love the enthusiasm and your passion to try to know all about this topic but i feel for the most part as long as we keep the soils fertilized with a bunch of nutrients but not flooding them with any to excess, ppl will be way better off than they are on their standard american diets. I suppose brix may be too simplistic but A lot of ppl get too carried away with the minute details (i know I have this kind of disorder with human nutrition but it's gettin better) when in reality human nutrition is in its infancy. I guess im speaking from the view of a very small scale farmer or individual, not somebody trying to make it extremely technical. Also I don't know much about plants and i know they aren't humans, but humans have pretty good self regulation and can excrete excess nutrients.

Third, your comment about the glycemic index was humourous. Anybody who has diabetes, if they're making strides to just eat fresh produce and whole foods alone, then it doesn't matter the difference between a lower or higher glycemic potato. If they are stuck in mostly junk food depending on medicine, then i can see why a lower glycemic potato would be better
in any case the glycemic index is misleading. Heres some interesting info
The fructose index is where you should be focusing on

Farukbd said...

Very important think.
"High Brix"
high brix

Farukbd said...

Very important think.
"High Brix"
high brix

Phosphorus Mineral said...

Phosphorus is found nutrition foods and carbonated soft drinks.

agriculture investments said...

Wow, looks facinating!

Anonymous said...

I think your making the assumption that a plant given fertilizers lacking in nutrients would produce a high brix reading in its fruit, however a simple trip to the grocery store with a refractometer will refute that. You can give your plant enough junk to have a high yield but unless the soil energy is high and minerals and nutrients present you won't get a high brix reading.
Also, a hybrid sweet corn's brix reading is irrelevant. Of course it will have a reading above 12, it was developed to shuttle more sugar into its fruit. Get that sweet corn above 30 then you can talk about nutrition. The 12+ brix benefit is most relevant when talking about the foliar brix levels.

m_astera said...

What I'm saying are two things:

1.That the super sweet hybrid corn proves that high Brix can be achieved simply by breeding, and

2.That so far there is no scientific evidence whatsoever that high Brix = high nutrient values or high mineral content.

Anonymous said...

What about brix level differences between morning and evening also taking samples from different parts of plants to determine defeiciency

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