What Is Aldehyde C-11 Undecylic?
Aldehyde C-11 Undecylic is a single aroma molecule belonging to the family of long chain aliphatic aldehydes explored by early 20th-century perfumers. It was first reported in the 1920s when chemists were searching for new materials that could boost the radiance of fine fragrances.
The ingredient is produced through modern organic synthesis that builds the required eleven-carbon chain from smaller fragments. This laboratory route allows precise control over purity and is more sustainable than older petrochemical methods. Many manufacturers now apply green chemistry guidelines such as solvent recycling and energy-efficient reactions.
Because it originates from a chemical process rather than a plant, Aldehyde C-11 Undecylic is classed as a synthetic raw material. There is no known natural source that can supply it in usable quantities.
At room temperature the material is a water-clear liquid. Handling is straightforward since it pours easily and does not crystallise in normal warehouse conditions.
In terms of market presence it is one of the staple aldehydes stocked by virtually every fragrance house. Widespread demand keeps the price moderate, making it affordable for large-scale consumer goods as well as prestige perfumes.
Formulators value its long shelf life, reasonable flashpoint and compatibility with both oil-based and water-based fragrance systems, making it a practical workhorse in the laboratory.
What Does Aldehyde C-11 Undecylic Smell Like?
This material falls under the aldehydic olfactory family known for their bright champagne-like sparkle.
On a blotter it opens with a quick burst of fizzy citrus reminiscent of freshly zested lemon coupled with a light watery breeze. Within a few minutes a soft waxy nuance comes forward, smoothing the initial sparkle without losing clarity. The overall impression stays clean and airy rather than soapy or fatty.
Perfumers think in terms of top, middle and base notes which describe how fast ingredients evaporate on skin. Aldehyde C-11 Undecylic sits at the top-middle border. It flashes loudly in the first minutes yet still lingers well into the heart phase, linking the initial freshness to the floral or woody core of a formula.
Projection is strong during the first hour giving a diffusive halo that can fill a room if overdosed. Despite its volatility it shows surprising staying power, often detectable for up to two days on a smelling strip before fading completely.
How & Where To Use Aldehyde C-11 Undecylic
This is a friendly material in the lab. It pours cleanly, does not crystallise and has a tolerable odour strength so you will not be floored the moment you open the bottle.
Perfumers turn to it whenever they need an instant burst of champagne sparkle at the top of a blend. In classic floral bouquets it lifts rose, jasmine or ylang so they feel freshly picked rather than dense. In modern citrus colognes it can extend the lemon or grapefruit note, giving extra fizz that lasts longer than natural zest oils. Woody or musky compositions also benefit because a few drops stop them feeling heavy.
Usage levels run from infinitesimal traces up to about 5 percent of the total fragrance concentrate. At 0.01 percent it becomes almost invisible yet the whole perfume smells more natural and airy. Around 0.5 percent it is clearly detectable, offering a lemony aldehydic flash that quickly blends into the heart. Near the upper limit the note is dominant and can feel metallic or fatty so overdosing should be a deliberate stylistic choice.
Formulators like it for fine fragrance, shampoo and candles where its tenacity survives heat or surfactants. It performs only moderately in bar soap or detergents because high pH environments can dull the sparkle, though it still adds lift if the budget allows. In softeners it brings a crisp top to otherwise creamy accords.
No special pre work is required beyond the usual dilution step. A 10 percent solution in alcohol or a solvent such as dipropylene glycol makes weighing and smelling easier while reducing the risk of nose fatigue.
Safety Information
Working with Aldehyde C-11 Undecylic is straightforward but certain precautions and considerations apply.
- Always dilute before evaluation: prepare a 10 percent or weaker solution so the vapour concentration stays low when smelling
- Avoid direct sniffing from the bottle: use a blotter or scent strip to prevent overwhelming exposure
- Ensure good ventilation: operate near a fume hood or open window to disperse airborne molecules quickly
- Wear personal protective equipment: nitrile gloves and safety glasses keep accidental splashes away from skin and eyes
- Health considerations: some aroma chemicals can irritate skin or trigger allergies. Brief exposure to low levels is generally safe but high or prolonged contact may be harmful. Consult a physician before use if you are pregnant or breastfeeding
Always consult the latest Safety Data Sheet provided by your supplier and review it regularly because the information can change. Follow all current IFRA guidelines for maximum concentration in finished products to ensure consumer safety.
Storage And Disposal
When stored correctly Aldehyde C-11 Undecylic remains in specification for roughly three to five years, sometimes longer if handled with care. Keep the original container tightly closed, limiting the amount of oxygen that can sneak inside and start oxidation.
Refrigeration is helpful but not essential. A shelf in a cool dark cupboard away from direct sun and any heat source is usually adequate. Temperature swings shorten shelf life so try to avoid leaving the bottle on a sunny lab bench between weighing sessions.
Use polycone caps on both neat material and dilutions. The soft insert gives a far better seal than dropper tops which often let volatiles escape and air creep back in. Whenever possible decant into the smallest practical bottle so the headspace stays minimal. Top up partially empty bottles or add inert gas if you have it on hand.
Label every container clearly with the name, date of receipt and any hazard phrases from the Safety Data Sheet. Good labeling saves headaches later and helps anyone in the workspace identify what they are handling at a glance.
For disposal do not pour leftovers down the drain. Small quantities can be absorbed onto sand or cat litter, sealed in a suitable container and handled as chemical waste according to local regulations. Larger volumes should go through a licensed waste contractor. The molecule is moderately persistent in the environment so controlled disposal is the responsible route.
Summary
Aldehyde C-11 Undecylic is a synthetic aroma chemical that delivers bright lemony sparkle with a watery clean twist. It bridges top and heart notes, lifts florals and adds fizz to citrus, woods or musks while staying detectable on a blotter for days.
Easy to handle and reasonably priced, it pops up in everything from luxury fine fragrance to everyday shampoo and candles. A pinch gives natural looking freshness, a higher dose creates the bold metallic edge of classic aldehydic perfumes, making it a fun tool for creative experiments across many accords.
Popularity comes from its versatility and stability, but watch out for oxidation if bottles are left half empty or exposed to heat. Cost is moderate, and the scent is quite specific so balancing it with other materials is key to avoid an overly soapy impression.
Used thoughtfully, Aldehyde C-11 Undecylic is a reliable ally that can brighten, extend and modernise a formula without stealing the spotlight.