A novel process for the manufacture of .beta.-keto alcohols from aldehydes comprising reacting a conjugated polyene aldehyde under basic conditions with a cyclocarbonate or derivative thereof. Certain carotenoid products of this process are novel compounds and are also an object of the present invention. The products, which for the most part belong to the carotenoid field, find corresponding use, for example, as colorants or pigments for foodstuffs, egg yolk, integuments and/or subcutaneous fat of poultry and flesh and/or integuments of fish and crustaceans.