The family of compounds nobody discusses

There is a third family of molecules in this plant, and it appears on almost no certificate. Neither the cannabinoids nor the terpenes cover it: these are the flavonoids.

They smell of nothing, or nearly. What they do is give colour — the yellows, reds and purples of a flower or a petal. They occur in tea, apples, onions, parsley, and in thousands of other plants.

This page describes what they are, where they sit, the two compounds that appear to be specific to this plant, what measuring them would require, why it is almost never commissioned, and what can and cannot be said about them.

⚠️ Scope. This page describes a process and what can be verified from documents. It does not describe what a product does to a person, gives no amounts, and does not replace a healthcare professional.

🔴 What a flavonoid is

The structure

A fifteen-carbon architecture organised in three rings. It is that shared structure that defines the family, independently of the chemical variations distinguishing its members.

The number

Several thousand distinct compounds have been described across the plant kingdom. Around twenty have been identified in this plant, which makes for a relatively modest profile.

Their role in the plant

They contribute to pigmentation, filter part of the ultraviolet spectrum, and participate in interactions with insects. These are surface and signalling functions.

What they do not do

They do not carry the aroma, which belongs to the terpenes, and they are not responsible for anything attributed to the cannabinoids. Three families coexist and do different things.

Where they sit

In the tissue

Unlike cannabinoids, they are not confined to the glands. They distribute through the leaves, stems and bracts, integrated into ordinary plant tissue.

The practical consequence

They cannot be concentrated by sieving the way trichome heads can. Mechanical separation does not recover them at all.

Their quantity

Measured in tenths of a per cent of dry mass, sometimes less. It is an order of magnitude comparable to the minor components of a terpene profile.

The variation

It depends on the variety, the light received and the temperature at the end of the cycle. Cold nights in particular alter their expression.

The cannaflavins

What the name covers

Three compounds, designated A, B and C, which have not been described in any other species to date. That is what makes them botanically interesting.

Their chemical particularity

They belong to a rare subgroup, the prenylated flavonoids, with few known equivalents elsewhere.

Their quantity

Very low, in the order of hundredths of a per cent. Isolating them requires large volumes of material and specific processes.

What can be said about them

That they exist, that they are documented, and that no authorised claim concerns them. The EU Register contains no entry for cannabidiol and none for these compounds either.

The other members

Quercetin

Present in onion, apple, caper and a great many plants. It is among the most studied flavonoids in the world, very far from this plant.

Kaempferol

Widespread in brassicas, tea and spinach. Its presence here is unremarkable: it is an ordinary compound of the plant kingdom.

Apigenin

Associated with chamomile and parsley. Like the others it occurs at low content and with no particular specificity.

Orientin and vitexin

Two glycosylated compounds also found in hawthorn and millet. They appear in detailed analytical work on the plant.

Anthocyanins and colour

What they are

A subgroup of the family, responsible for red, blue and purple shades depending on the acidity of the medium they sit in.

What triggers their expression

Cold at the end of the cycle, principally. A drop in night temperatures promotes their accumulation in the tissue, which produces purple flowers.

The genetic share

Some varieties produce them regardless, others never. Cold amplifies an existing predisposition rather than creating one.

What colour does not indicate

Neither cannabinoid content, nor quality, nor aromatic profile. A purple flower is neither more nor less concentrated than a green one of the same variety.

🔴 Why they are never measured

No obligation

Regulation addresses total THC. Nothing requires flavonoids to be measured, either for batch compliance or for labelling.

The cost of the analysis

It requires a dedicated liquid chromatography run with specific reference standards. It is a separate commission, added to the analyses already ordered.

The absence of demand

Almost no buyer asks for it, because almost nobody knows these compounds exist. Demand creates the supply of analysis, and here it is non-existent.

The result

Across thousands of published certificates it is rare to find one carrying a flavonoid row. That is not an omission but a rational economic choice.

What an analysis would show

The method

High-performance liquid chromatography with ultraviolet detection or mass spectrometry. A laboratory accredited to ISO/IEC 17025 can perform it.

The format of the result

A list of compounds with their contents, in milligrams per gram. The values would be low, often close to the limit of quantification.

What could be drawn from it

A variety signature, potentially useful for distinguishing two closely related genetics. That is the most plausible use.

What could not

Any information about compliance, batch cleanliness or use value. The rows that matter for those questions are elsewhere.

What processing does to them

Drying

They resist considerably better than terpenes. Not being volatile, they do not evaporate and they tolerate temperatures that would destroy an aromatic profile.

Light

Prolonged exposure degrades the anthocyanins in particular. It is visible: a purple flower left in light progressively loses its tint.

Extraction

Their solubility differs from that of the cannabinoids. A carbon dioxide extract recovers few; ethanol processes carry more, which contributes to the colour of the finished product.

The colour of an oil

It comes partly from these compounds and partly from residual chlorophyll. A dark tint indicates neither concentration nor a defect.

The full-spectrum connection

The argument commonly made

That the presence of the whole set of plant compounds is worth more than an isolated molecule. It is a widespread sales argument and it frequently includes the flavonoids.

What the document allows checking

The cannabinoid composition, row by row, and sometimes the terpene profile. Almost never the presence of flavonoids.

What follows

The argument concerns a composition part of which is not measured. The promise exceeds what the certificate demonstrates.

The defensible position

Noting that raw material contains these compounds, without asserting what their presence contributes. The distinction is narrow and it separates a description from a claim.

What the framework says

The food setting

An ingested product falls within the scope of rules on novel foods. The question turns on consumption history, independently of which molecule is featured.

Labelling

Food information rules require a complete ingredient list. A plant extract appears as such, without a breakdown of its flavonoid composition.

Claims

No authorisation exists for these compounds in this context. The European register is the reference and it contains nothing on the subject.

What remains sayable

The botanical and chemical description: which compounds, at what contents, in which part of the plant. Everything beyond that leaves the framework.

What light changes

The filter role

These compounds absorb part of the ultraviolet spectrum. A plant exposed to intense sunlight produces more of them, which is a protective response of an entirely ordinary kind.

Indoor against outdoor

Cultivation under artificial light receives a spectrum poorer in ultraviolet than sunlight. Their expression is generally lower there, without any bearing on cannabinoid content.

What this produces visually

Outdoor flowers sometimes more coloured, with shades that indoor cultivation rarely reproduces. It is a documented aesthetic difference, not an indicator of value.

The limit of the observation

Nothing permits deducing a growing method from a colour. Too many factors intervene, beginning with the genetics themselves.

Stability

Against heat

They tolerate temperatures that would destroy a terpene profile. Drying at thirty degrees barely affects them, while it appreciably thins the aroma.

Against oxygen

Oxidative degradation exists but proceeds slowly. It shows over months rather than weeks and does not alter the smell, since they do not contribute to it.

Against light

This is their principal weakness, particularly for the anthocyanins. A purple flower stored near a window visibly loses its tint within weeks.

What follows

The opaque container recommended for other reasons also protects the colour. No additional precaution is required.

What separates the three families

Location

Cannabinoids and terpenes sit in the trichome glands, outside the tissue. Flavonoids distribute through the tissue itself, which rules out mechanical concentration.

Volatility

Only the terpenes evaporate at room temperature. The other two families stay put, which is why a flower loses its smell long before it loses its colour or its content.

Measurement

Cannabinoids are always measured, terpenes sometimes, flavonoids almost never. That hierarchy follows exactly the one of regulatory obligation and commercial demand.

What the buyer perceives

The terpenes are smelled, the flavonoids are seen, and nothing of the cannabinoids is perceived. The only family that matters in regulation is also the only one entirely invisible.

Common errors

Confusing them with terpenes

Two distinct families. One carries colour, the other smell; one sits in the tissue, the other in the glands.

Attributing purple to something else

Neither a stronger variety nor a particular process. It is a response to cold on a genetic that permits it.

Believing a product is verified because it mentions them

A commercial mention is not a measurement. Without a row on the certificate the assertion rests on nothing.

Looking for an effect

The subject invites assertions the European register does not permit. Describing the molecule remains possible; saying what it does is not.

What it would take for this to change

The demand side

Buyers would have to ask for the row often enough that its absence became a commercial disadvantage. That is how the terpene profile went from rare to common on certificates over the last few years.

The cost side

The analysis would have to become cheap enough to bundle. Laboratories price by run, and a dedicated liquid chromatography pass with its own standards is not something that gets thrown in.

The regulatory side

Nothing suggests a requirement is coming. The framework addresses total THC and contaminants, and there is no obvious reason for it to extend to pigmentation compounds.

The realistic assessment

It will stay unmeasured. That is not a scandal, it is a rational allocation of analytical spending, and the honest response is to stop citing what nobody measures.

The colour question at purchase

What a buyer actually sees

A shade, and nothing else. The pigments producing it are real compounds with a documented botanical role, and none of that role concerns anything a buyer is purchasing the product for.

Why purple sells

Because it looks unusual and unusual reads as special. The premium attached to it is a straightforward aesthetic premium, and there is nothing wrong with paying it knowingly.

What settles the value question

The per-milligram calculation, which is indifferent to colour. Where two products differ in shade and agree on their certificates, the cheaper one is the rational choice on the evidence.

The honest summary

Colour is worth what you enjoy paying for it. It is not worth anything a document would recognise, and those two statements are compatible.

A short glossary

Flavonoid

A plant compound with fifteen carbon atoms in three rings, involved notably in pigmentation.

Cannaflavin

A subgroup of three compounds, designated A, B and C, described to date only in this plant.

Anthocyanin

A pigment of the flavonoid family, responsible for red, blue and purple shades depending on medium acidity.

Liquid chromatography

The separation method used to measure these compounds. Distinct from the gas chromatography used for terpenes.

Glycosylated

Said of a molecule with a sugar attached. This is the case for several flavonoids present here.

The five checks that apply to any product

The batch certificate

Request it with the number printed on the packaging. A general document for the product line does not cover this batch, and those differences are exactly what it should record.

Total THC

Delta-9-THC plus THCA multiplied by 0.877, because THCA becomes THC under heat and the limit applies to the sum, not to either value alone.

Price per milligram

A division, not an opinion. The only figure that makes two products comparable, whatever the format, process and pack size.

The claims

Without an authorisation number in the EU Register these are assertions, not data — and for cannabidiol that register contains no authorised entry to this day.

The seller’s details

Company name, address and contact. Without them there is also no counterparty to turn to if something turns out to be wrong.

How this connects to the rest

With flower colour

It is the complete explanation of the purple phenomenon, often wrongly attributed to other causes. Cold reveals a genetic predisposition.

With terpenes

Two families that coexist without overlapping. One is routinely measured, the other almost never, for economic rather than technical reasons.

With full spectrum

The commercial argument rests on a partly unmeasured composition. The certificate shows how far the demonstration actually goes.

With reading a certificate

Their absence from reports illustrates a general rule: what is not measured is not verifiable, whatever a seller’s conviction.

What this is for in practice

To understand a colour

A purple flower is explained by cold at the end of the cycle. That is botanical information, not a purchasing criterion.

To evaluate an argument

When a product foregrounds its flavonoid richness, ask for the corresponding row on the certificate. The answer is instructive.

To place a family

Knowing that three families of compounds exist, and that only two are routinely measured, helps in reading what a report covers and what it leaves aside.

Not to overpay

A mention of unmeasured compounds justifies no price difference. The per-milligram calculation stays grounded in what is quantified.

Frequently asked questions

What is a flavonoid? A plant compound with fifteen carbon atoms, present in nearly all plants, involved in pigmentation and ultraviolet protection.

Are they specific to hemp? No, with two exceptions. Cannaflavins A, B and C have not been described in any other species to date.

Do they give the smell? No, that is the terpenes. Flavonoids are not volatile and contribute practically nothing to aroma.

Do they explain purple colour? Yes, through the anthocyanins, whose expression is promoted by cold at the end of the cycle on certain genetics.

Are they measured on certificates? Almost never. Nothing requires it, the analysis is separate and costly, and practically no buyer asks for it.

How much does a flower contain? Tenths of a per cent of dry mass, sometimes less. Cannaflavins are measured in hundredths.

Can a benefit be claimed for them? No. No authorised entry appears in the European register, for them or for cannabidiol.

Do they survive drying? Far better than terpenes, since they are not volatile. Light degrades them more than heat does.

Do they end up in an oil? Partly, depending on the extraction process. Ethanol carries more of them than supercritical carbon dioxide.

Does an oil’s colour come from them? Partly, along with residual chlorophyll. A dark tint indicates neither concentration nor a defect.

What we check and what we do not

We check what can be checked from documents: official registers, declared contents, certificates of analysis, arithmetic. We test no products, rank nothing, and assert no effects.

This family of compounds occupies an unusual position: it is real, documented for decades, specific for two of its members, and yet absent from virtually every document accompanying a product. It is therefore simultaneously an established fact and an unverifiable one for a buyer.

What stays usable is modest: understanding where a colour comes from, knowing that a third family exists, and asking for the corresponding row when a seller invokes it. In most cases there will not be one, which is itself an answer.