What Is Maltol?
Maltol, a cyclic ketone-ether-alcohol compound, is also known by its IUPAC name, 3-hydroxy-2-methyl-4H-pyran-4-one. Commonly referred to as veltol, palatone, and larixic acid, it naturally occurs in larch bark, pine needles, wood tar and oil, wheat, soybeans, and butter, and is produced as a smoke condensate in malt coffee production.
Uses of Maltol
In the food industry, maltol serves as a versatile flavoring agent, enhancing the aroma and sweetness of baked goods, beverages, and animal feeds. It is effective in small concentrations, varying from 5 to 75 ppm to enrich sweetness and up to 30 ppm in fruit flavorings. Extracts containing 3-8% maltol from Abies sachalinensis leaves are utilized for their caramel notes and flavor-enhancing properties, particularly in strawberry flavor compositions.
Recognized for its low toxicity and irritation levels, the WHO has established an acceptable daily intake of maltol at up to 1 mg/kg body weight.
Properties of Maltol
Maltol’s chemical structure is C6H6O3, with a molecular weight of 126.11, under the CAS number 118-71-8. At room temperature, it presents as white crystals, melting at 161.5°C and capable of sublimation at 93°C. Known for its caramel-like aroma and fruity, strawberry-like flavor in dilution, its taste profiles become more pronounced with increased concentration. Soluble in alcohols such as ethanol and propylene glycol, chloroform, benzene, ether, and acetone, its water solubility is about 10.9 mg/mL at 15°C. Maltol’s acidity is denoted by a pH of 5.3 in a 0.5% aqueous solution and a pKa of 8.6.
Other Information About Maltol
1. How Maltol Is Produced
Maltol is extracted from natural sources like beech wood tar, pine needles, chicory, and young larch tree bark, or synthetically produced from furfural or piperidine. It is purified through recrystallization from chloroform, toluene, or a 50% ethanol solution.
2. Precautions for Handling and Storage
Handling Precautions
Maltol should be handled with care, avoiding exposure to strong oxidizing agents. Use protective equipment, such as gloves and glasses, and a dust mask if necessary. Ensure to wash hands and face after handling.
In Case of Fire
Combat fires involving maltol with water spray, foam, powder fire extinguishers, or carbon dioxide, but avoid direct water spray due to the risk of releasing toxic gases.
For Storage
Store maltol in a tightly sealed container, in a cool, well-ventilated area away from light, heat, and ignition sources. The storage area should be locked to restrict access.