Rooibos Extract Starts Fading the Moment It Is Made
The label on a supplement bottle or a jar of face cream says "rooibos extract." Here is what that actually means, how a factory makes it, and the one problem the powder creates for itself the moment it is made.
A packet of rooibos is not the only thing the harvest becomes. Read the ingredient list on a rooibos supplement capsule, a soothing face cream, or a bottle of ready-to-drink iced tea, and you will often find the same two words: rooibos extract. It is not simply crushed leaf. It is a separate product with its own factory step, made by soaking purified leaf and stem in hot water, filtering out the solids, concentrating what is left, and spray-drying it into a fine, water-soluble powder, the South African Rooibos Council describes. That powder, not a teabag, is where a real and growing slice of each year's harvest disappears to, and it comes with a problem the leaf in your cupboard does not have: it starts breaking down almost as soon as it is made.
From sieve dust to soluble powder
The raw material for an extract does not usually come from the best of the harvest. When rooibos is graded after drying, the finest material a sieve run leaves behind, the dust too small to steep loose without leaving grit in the cup, is sold on for exactly this purpose rather than wasted, an industry standard the site has described before. Rooibos Ltd, the Clanwilliam-based processor descended from the old state control board, runs its own on-site extraction plant for turning that material, along with purpose-grown leaf, into what it calls water-soluble, spray-dried powder extracts, the company's own product page states. The finished extract ships in bulk, 2.5 or 18 kilogram bags (about 5.5 or 40 pounds) inside food-grade plastic, with a stated shelf life of three years, for buyers who blend it into their own products rather than sell it as tea themselves.
The hot-water soak is the step that actually separates an extract from a cup of tea. Steeping a teabag pulls flavour and colour into water you then drink whole, leaf and all left behind in the bag. Making an extract pulls the same compounds out on an industrial scale, then throws the spent leaf away and keeps only the liquid, which is reduced by evaporation and dried into a powder concentrated enough that a small amount reconstitutes into a full-strength cup, or disappears invisibly into a cream, a capsule, or a baked good.
Two extracts, the same as the two teas
Rooibos extract is not one product. It comes in red and green, the same divide that runs through the leaf itself. Red extract is made from fermented, oxidised leaf, the everyday reddish-brown tea. Green extract is made from leaf dried quickly to skip that oxidation, the SA Rooibos Council notes, the same distinction the Ministry has set out for the leaf itself. The industry markets green extract specifically for its higher retained level of aspalathin, rooibos's signature antioxidant, largely broken down during the fermentation that makes red rooibos red, so a buyer who wants the compound rather than the familiar taste generally reaches for the green version.
What it actually ends up in
Once it is a powder, rooibos extract stops being recognisable as tea at all. The South African Rooibos Council lists it going into flavoured water, energy drinks, baked goods, dairy products, and sauces on the food side, and into anti-ageing creams and soothing balms for sensitive skin on the cosmetic side, alongside emerging use in supplement capsules aimed at heart health and relaxation. Two recent laboratory studies give a sense of how far from the teapot this goes: a Spanish team dosed anxious zebrafish and roundworms with a standardised green-rooibos preparation, not a cup at all, and a University of Malaga lab folded rooibos extract into sunscreen formulations and found it slowed the breakdown of the sun filters already in the mix. Neither result says anything about drinking the tea itself, and the Ministry will not stretch either one into a health claim it does not support. What both studies confirm is simply how far the extract travels once it leaves the leaf behind.
A market-research estimate the Rooibos Council itself cites put the global market for the green form of the extract at roughly 141 million US dollars, projected to reach around 227 million dollars within five years at a growth rate near 6.3 percent a year, as of a January 2025 industry snapshot. The number will have moved by the time you read this, the way any market estimate does, but the direction is the point: the extract side of the industry has grown into a business in its own right, running alongside the packet of tea in your cupboard rather than underneath it.
The powder's own problem: it does not keep
Turning rooibos into a shelf-stable powder does not preserve aspalathin, the compound the whole green-extract trade is built on. It puts the compound under measurable stress instead, a fact the marketing on a jar or a bottle rarely says out loud. Chantelle Human's 2019 doctoral research at Stellenbosch University, later published with the same research team in the journal Molecules, tracked exactly how much aspalathin a spray-dried green powder loses in storage, and the range is wide enough to matter. Sealed in glass at 40 degrees Celsius (about 104°F) for twelve months, different iced-tea powder formulations lost between roughly 9.7 percent and 90.3 percent of their aspalathin, the study found, depending entirely on what else was mixed into the powder and how it was packaged. Semi-permeable sachets fared worse than sealed glass at the same temperature. Citric acid, a common flavouring and preservative, measurably sped the loss. So did swapping ordinary sugar for xylitol. Ten degrees of extra heat, from 30 to 40 Celsius (about 86 to 104°F), made the decline sharply worse across every formulation tested.
How a processor fights back
The industry's answer is to trap the compound before it can escape. Human's thesis tested both microencapsulation, coating the extract in a protective carrier before spray-drying, and the newer, finer nanoencapsulation, and found the two carriers behave very differently. Maltodextrin and inulin, both ordinary carbohydrate carriers, held up well: over 76 percent of the powder survived processing as a usable yield, moisture stayed under 3.5 percent, and better than 95 percent of the aspalathin was retained straight out of the dryer. Chitosan, a carrier drawn from crustacean shells that works well for some other plant compounds, performed poorly here, with lower yield and weaker retention. At the smaller, nanoencapsulation scale, particles built from a polymer called Eudragit S100 held about 55 percent of the aspalathin loaded into them at a particle size of roughly 190 nanometres, though the thesis found this finer encapsulation did not actually help the compound cross the gut wall any better than plain, unencapsulated aspalathin did. The engineering solves the storage problem. It does not, on its own, make the compound work any harder once swallowed.
The researchers' own recommendation is plain rather than technical: keep the finished powder at or below 30 degrees Celsius and protect it from moisture, the two conditions that matter most regardless of which carrier a formulator chose. It is the same advice the Ministry would give a reader about a tin of loose leaf, said instead about a product built to survive a much longer, much less forgiving supply chain, a capsule bottle on a warm shelf or a sachet in a delivery van, rather than a kettle a few steps from the cupboard.
The leaf on your shelf is not the extract
None of this changes what the leaf in your own cupboard is doing. Loose or bagged rooibos, kept dry and out of direct heat, is stable tea. It is still caffeine-free, and it still carries its full share of aspalathin, the very compound the extract above works so hard just to keep, and none of the degradation described above happens meaningfully at that pace or scale. Extract is a different product, built for industrial use where a steeped cup would be impractical, and it is engineered, imperfectly, to survive a much harder supply chain than the box in your kitchen ever faces. The next time "rooibos extract" turns up on an ingredient list, a supplement bottle or a jar of cream, that is the process behind it: a hot-water extraction, a spray dryer, and a formulator working out how much of the plant's own signature compound will actually survive to reach you.
Sources
- Rooibos Extracts, South African Rooibos Council, on the extraction process (hot-water soak, filtration, concentration, spray-drying), the red/green extract distinction, market applications, and the cited market-size estimate for green rooibos extract.
- Products, Rooibos Ltd, on the company's on-site extraction plant, packaging formats (2.5 and 18 kilogram bags), and stated three-year shelf life.
- Rooibos Production and Processing, Carmién Tea International, on the four-stage sieving process (rolling, vibrating, maxi, and indent) that sorts the tea by size and quality during grading.
- Human, C., The physicochemical properties and stability of aspalathin in micro- and nanoencapsulated green rooibos extract formulations, PhD thesis, Stellenbosch University (2019), on microencapsulation yield, moisture content, and aspalathin retention for maltodextrin, inulin, and chitosan carriers, and on Eudragit S100 nanoencapsulation's efficiency, particle size, and intestinal-permeability findings.
- Human, de Beer, Muller et al., Shelf-Life Stability of Ready-to-Use Green Rooibos Iced Tea Powder, Molecules 26(17):5260 (2021), on measured aspalathin degradation (9.67 to 90.3 percent at 40°C over twelve months) across packaging types and formulation ingredients, and the resulting storage recommendation.