E160e: properties, uses, pros, cons, safety
(Typically referring to β-apo-8'-carotenal, a carotenoid colourant, often listed as E160e)

Description

• Carotenal (commonly β-apo-8'-carotenal) is a fat-soluble carotenoid used primarily as an orange to reddish-orange colouring agent in foods, beverages and supplements.

• Chemically related to β-carotene, it has a shorter carbon chain and an aldehyde group, which modifies its colour and solubility profile.

• It is usually produced by chemical synthesis or via fermentation/biotechnological routes, then formulated in oils, emulsions, or powders for easy dispersion.

• Used where a vivid orange hue is desired and can partially substitute or complement other carotenoids (β-carotene, paprika, annatto).

Indicative nutritional values per 100 g

(For pure Carotenal; in practice used at very low levels)

• Energy: ~600–700 kcal (fat-like, but irrelevant at use levels)

• Protein: 0 g

• Carbohydrates: 0 g

• Lipids: 90–100 g (as carotenoid and carrier oils in formulations)

  • SFA (first occurrence): depends on carrier oil in commercial preparations

  • MUFA: variable (carrier-dependent)

  • PUFA: variable

  • TFA: not expected in pure carotenoid; traces possible from carriers if poorly controlled

• Fibre: 0 g

• Vitamins/minerals: not nutritionally relevant at typical doses

• In real food products, Carotenal contributes negligible calories because used at ppm (mg/kg) levels.

Key constituents

• β-Apo-8'-carotenal (or related carotenal structures):

  • polyene chain with conjugated double bonds (chromophore);

  • terminal aldehyde group.

• Possible isomers (all-trans and cis forms) depending on processing and storage.

• In formulated products:

  • carrier oils (e.g., vegetable oils) or

  • encapsulating agents (e.g., starch, gum arabic, maltodextrin)

  • emulsifiers and stabilisers (mono- and diglycerides, antioxidants, etc.).

Production process

• Starting materials: carotenoid intermediates from petrochemical, fermentation, or plant-based sources (depending on manufacturer).

• Synthesis or biotransformation of Carotenal via controlled reactions (for synthetic routes) or fermentation and subsequent conversion (for biological routes).

• Purification by crystallisation and/or chromatography to achieve high carotenoid purity.

• Formulation:

  • oil solutions (Carotenal dissolved in edible oil);

  • emulsions or suspensions for beverages;

  • spray-dried powders for dry mixes.

• Standardisation to a defined active content (% Carotenal).

• Produced under GMP/HACCP, with controls for identity, purity, residual solvents (if relevant), and contaminants.

Physical properties

• Appearance (pure): deep orange to red crystals or crystalline powder.

• Solubility: fat-soluble; insoluble in water but dispersible via emulsions or encapsulation.

• Melting point: moderately high (depends on isomeric composition).

• Light and oxygen sensitivity: prone to oxidation and fading; requires protection.

• Stability: better in low-oxygen, low-light, cool conditions; stability varies by formulation.

Sensory and technological properties

• Colour: provides orange to reddish-orange tones; intensity depends on dosage and matrix.

• Generally no significant flavour or odour at normal use levels.

• Effective at low concentrations, giving strong tinting strength.

• Works well in fat-containing systems (margarine, spreads, cheese analogues) and in beverages using emulsified/encapsulated forms.

• Sensitive to heat, light, oxygen, and pro-oxidant metals; antioxidants and appropriate packaging enhance stability.

Food applications

• Beverages: soft drinks, juice drinks, sports and energy beverages (as an orange shade).

• Dairy and dairy analogues: flavoured milks, yoghurt, cheese spreads, processed cheese, ice cream.

• Bakery and confectionery: cakes, fillings, icings, sugar confectionery.

• Fats and oils: margarine, spreads, salad dressings.

• Snacks and savoury products: extruded snacks, seasoning blends, sauces, soups.

• Dietary supplements: capsules, tablets, gummies, especially where a carotenoid colour is desired.

Nutrition & health

• Carotenal is a carotenoid, but is not normally used or positioned as a vitamin A source in the same way as β-carotene; its provitamin A activity, if any, is limited and not usually a primary function claim.

• In practical use levels, it does not significantly impact energy or macronutrient intake.

• Safety evaluations by authorities typically consider Carotenal acceptable within specified ADI (acceptable daily intake) or use-level limits.

• No known direct adverse health effects at permitted doses in the general population, though long-term high intakes of some carotenoids have specific considerations (not normally relevant here due to low use levels).

Portion note

• Typical use levels in foods: a few mg/kg (ppm range), depending on desired colour intensity and matrix.

• Contribution per portion is extremely low (micrograms to low milligrams), nutritionally negligible.

Allergens and intolerances

• Carotenal itself is not an allergen.

• Potential allergenic risks come from:

  • carriers or emulsifiers (e.g., milk-derived proteins, soy lecithin) used in formulated products;

  • cross-contamination in production lines.

• Finished products should be checked for allergen declarations related to carriers, not to Carotenal itself.

Storage and shelf-life

• Store in cool, dry conditions, away from heat and direct light.

• Protect from oxygen (nitrogen-flushed packaging, antioxidants) to minimise oxidation.

• Shelf-life: often 12–24 months for commercial formulations, depending on:

  • packaging;

  • antioxidant system;

  • storage temperature;

  • product form (oil, emulsion, powder).

• Colour loss over time is the main degradation marker.

Safety & regulatory

• Regarded as a colour additive; subject to specific regulations (e.g., often designated as E160e in the EU and allowed as a food colouring under defined conditions).

• Must comply with purity criteria:

  • minimum active Carotenal content;

  • limits for solvents, heavy metals, and other contaminants.

• Inclusion in foods must respect:

  • maximum permitted levels or quantum satis, according to local law and category;

  • labelling rules for colours and additives.

• Manufacturing sites follow GMP/HACCP, with batch traceability and quality control.

The Panel on Food Additives concluded that E160e was not of concern with respect to genotoxicity, but indicated an ADI (Acceptable Daily Intake) of 0.05 mg/kg bw/day (1).

Labeling

• Typically declared in ingredient lists as:

  • “Carotenal” or “β-apo-8'-carotenal”;

  • sometimes with regulatory code, e.g. “colour: E160e”.

• In some regions may be grouped under “colouring (Carotenal)”.

• Any carriers or additives in the colour preparation must also be listed (e.g., vegetable oil, emulsifiers, antioxidants).

Troubleshooting

• Colour fading in product:

  • likely due to light/oxygen/heat → improve packaging (light barrier, oxygen barrier), add antioxidants, reduce processing temperature/time.

• Non-uniform colour distribution:

  • insufficient mixing or inappropriate dosage form → use better dispersion/emulsion, adjust mixing conditions.

• Colour shift (orange to dull/brown):

  • oxidation of carotenoid → enhance antioxidant system, monitor storage and metal contaminants.

• Sedimentation in beverages:

  • unstable emulsion or incorrect particle size → use stabilisers, adjust emulsifier system and homogenisation.

Sustainability & supply chain

• Environmental impact depends on the source route (synthetic vs fermentation/plant-derived) and on:

  • energy for synthesis, purification and drying;

  • solvents and reagents used (and their recovery);

  • packaging and transport.

• Manufacturers should manage process effluents, employing wastewater treatment monitored with BOD/COD indicators, and minimise solvent emissions where applicable.

• Encapsulation/ carriers often use plant-based materials (starches, gums), which can be sourced from more sustainable supply chains.

Main INCI functions (cosmetics)

(when used as “Carotenal”, “β-Apo-8'-Carotenal” or similar)

• Colourant (orange/red shades) in lipsticks, balms, creams, and makeup.

• Antioxidant-related aesthetic claims due to carotenoid nature (primarily marketing).

• Adds a “carotenoid” or “provitamin-like” image in cosmetic formulations, particularly in sun- and skin-care lines (even if real vitamin A activity is limited or not claimed).

Conclusion

Carotenal is a specialised carotenoid colourant that delivers bright orange to reddish hues in a wide range of foods, beverages, and supplements. Used at very low levels, it has negligible nutritional impact but strong technological value as a stable, intense colour source when appropriately formulated and protected from oxidation. Compliance with regulatory limits, careful formulation (emulsions/encapsulation), and suitable storage and packaging are essential to maintain colour intensity and product quality over shelf-life.

Mini-glossary

• SFA – Saturated fatty acids: may be present in small amounts, depending on the carrier oil used in formulated Carotenal preparations.

• MUFA – Monounsaturated fatty acids: part of the fatty acid profile of vegetable carrier oils.

• PUFA – Polyunsaturated fatty acids: more oxidation-prone lipids sometimes present in carrier oils.

• TFA – Trans fatty acids: not intrinsic to Carotenal; any presence relates to carrier fats and should be controlled.

• GMP/HACCP – Good Manufacturing Practices / Hazard Analysis and Critical Control Points, systems to ensure safety, hygiene, and quality in production.

• ADI – Acceptable Daily Intake, the estimated amount of a substance that can be ingested daily over a lifetime without appreciable health risk.

• BOD/COD – Biological / Chemical Oxygen Demand, indicators of the impact of wastewater on the environment.
  
  References_____________________________________________________________________

  (1) EFSA Scientific Opinion on the re-evaluation of β-apo-8’-carotenal (E 160e) as a food additive EFSA Journal 2012;10(3):2499  doi 10.2903/j.efsa.2012.2499

  Abstract. The Panel on Food Additives and Nutrient Sources added to Food provides a scientific opinion re-evaluating the safety of β-apo-8’-carotenal (E 160e) as a food additive in the EU. β-Apo-8’-carotenal was previously evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1974 and the EU Scientific Committee for Food (SCF) in 1975 and 2000. Both committees established an Acceptable Daily Intake (ADI) of 0–5 mg/kg bw/day, which was withdrawn by the SCF in 2000. The Panel concluded that the available in vitro and in vivo genotoxicity studies do not give reason for concern with respect to genotoxicity. Upon a public call for data two subchronic toxicity studies in rats performed according to OECD guidelines and under GLP became available for evaluation. Based on the 13-week study the Panel established that based on increased incidence of eosinophilic droplets in the kidneys the LOAEL was 10 mg β-apo-8’-carotenal active ingredient/kg bw/day. Upon a public call for data two additional studies on reproductive and developmental toxicity became available revealing a NOAEL of 500 mg/kg bw/day, the highest dose level tested. Overall, the Panel concluded that the present database on β-apo-8′-carotenal provides a basis to revise the ADI. The Panel concluded that based on the LOAEL of 10 mg/kg bw/day from the 13 week study in rats and an uncertainty factor of 200, an ADI for β-apo-8’-carotenal of 0.05 mg/kg bw/day can be established. Exposure estimates at Tier 3 indicate that the newly set ADI is reached for adults on average and exceeded by adults at the 95th percentile and by children on average and at the 95th/97.5th percentile.

  Ragnoni E, Di Donato M, Iagatti A, Lapini A, Righini R. Mechanism of the intramolecular charge transfer state formation in all-trans-β-apo-8'-carotenal: influence of solvent polarity and polarizability. J Phys Chem B. 2015 Jan 15;119(2):420-32. doi: 10.1021/jp5093288. 

  Abstract. In this work we analyzed the infrared and visible transient absorption spectra of all-trans-β-apo-8'-carotenal in several solvents, differing in both polarity and polarizability at different excitation wavelengths. We correlate the solvent dependence of the kinetics and the band shape changes in the infrared with that of the excited state absorption bands in the visible, and we show that the information obtained in the two spectral regions is complementary. All the collected time-resolved data can be interpreted in the frame of a recently proposed relaxation scheme, according to which the major contributor to the intramolecular charge transfer (ICT) state is the bright 1Bu(+) state, which, in polar solvents, is dynamically stabilized through molecular distortions and solvent relaxation. A careful investigation of the solvent effects on the visible and infrared excited state bands demonstrates that both solvent polarity and polarizability have to be considered in order to rationalize the excited state relaxation of trans-8'-apo-β-carotenal and clarify the role and the nature of the ICT state in this molecule. The experimental observations reported in this work can be interpreted by considering that at the Franck-Condon geometry the wave functions of the S1 and S2 excited states have a mixed ionic/covalent character. The degree of mixing depends on solvent polarity, but it can be dynamically modified by the effect of polarizability. Finally, the effect of different excitation wavelengths on the kinetics and spectral dynamics can be interpreted in terms of photoselection of a subpopulation of partially distorted molecules.

  Harrison EH. Carotenoids, β-Apocarotenoids, and Retinoids: The Long and the Short of It. Nutrients. 2022 Mar 28;14(7):1411. doi: 10.3390/nu14071411. 

  Abstract. Naturally occurring retinoids (retinol, retinal, retinoic acid, retinyl esters) are a subclass of β-apocarotenoids, defined by the length of the polyene side chain. Provitamin A carotenoids are metabolically converted to retinal (β-apo-15-carotenal) by the enzyme β-carotene-15,15'-dioxygenase (BCO1) that catalyzes the oxidative cleavage of the central C=C double bond. A second enzyme β-carotene-9'-10'-dioxygenase cleaves the 9',10' bond to yield β-apo-10'-carotenal and β-ionone. Chemical oxidation of the other double bonds leads to the generation of other β-apocarotenals. Like retinal, some of these β-apocarotenals are metabolically oxidized to the corresponding β-apocarotenoic acids or reduced to the β-apocarotenols, which in turn are esterified to β-apocarotenyl esters. Other metabolic fates such as 5,6-epoxidation also occur as for retinoids. Whether the same enzymes are involved remains to be understood. β-Apocarotenoids occur naturally in plant-derived foods and, therefore, are present in the diet of animals and humans. However, the levels of apocarotenoids are relatively low, compared with those of the parent carotenoids. Moreover, human studies show that there is little intestinal absorption of intact β-apocarotenoids. It is possible that they are generated in vivo under conditions of oxidative stress. The β-apocarotenoids are structural analogs of the naturally occurring retinoids. As such, they may modulate retinoid metabolism and signaling. In deed, those closest in size to the C-20 retinoids-namely, β-apo-14'-carotenoids (C-22) and β-apo-13-carotenone (C-18) bind with high affinity to purified retinoid receptors and function as retinoic acid antagonists in transactivation assays and in retinoic acid induction of target genes. The possible pathophysiologic relevance in human health remains to be determined.

  Gordon HT, Bauernfeind JC. Carotenoids as food colorants. Crit Rev Food Sci Nutr. 1982;18(1):59-97. doi: 10.1080/10408398209527357. 

  Abstract. The carotenoids are a chemically related group of pigments which occur widely and abundantly in nature. Fruits, vegetables and vegetable oils, dairy products, leaves, shrimp, lobster, the plumage of exotic birds, all contain carotenoids. Chemically, the carotenoids may be divided into carotenes, made up of carbon and hydrogen only, and oxycarotenoids containing oxygen in addition to carbon and hydrogen. The use of carotenoid-containing plant extracts for coloring foods has been practiced for centuries and continues today. Advances in chemical synthesis resulted in the complete laboratory synthesis of beta carotene in 1950. Since then the commercial synthesis of several carotenoids has been accomplished. In the U.S. three of these commercially synthesized carotenoids, beta-carotene, beta-apo-8'-carotenal, and canthaxanthin, are accepted color additives for use in foods and are exempt from certification. These three carotenoids are also widely accepted for food use in other countries. This paper deals with the chemistry and synthesis of these three carotenoids, with special emphasis on their numerous commercially available market forms and their characteristics, and on the application of these carotenoids in the coloring of food products.

  Šebelík V, Kuznetsova V, Šímová I, Polívka T. Carotenoid radical formation after multi-photon excitation of 8'-apo-β-carotenal. Phys Chem Chem Phys. 2025 Mar 6;27(10):5080-5086. doi: 10.1039/d4cp04373a. 

  Abstract. Carotenoids containing a conjugated CO group exhibit complex excited-state dynamics that are influenced by solvent polarity due to the involvement of an intramolecular charge transfer (ICT) state. Our study explores the excited-state behavior of 8'-apo-β-carotenal under multi-photon excitation conditions. Using near-infrared (1300 nm) multi-photon excitation, we observe the formation of a cation radical of 8'-apo-β-carotenal, a process distinct from those following one-photon visible or UV excitation. Our findings suggest that this radical formation results from multi-photon excitation involving a higher-lying dark state, supported by intensity-dependent experiments. This work demonstrates that radical generation is a characteristic of this higher excited state and is not produced during relaxation from the S1/ICT state. The results open new pathways for understanding carotenoid radical formation mechanisms under intense multi-photon excitation.