Spices and fragrances

Physical and chemical properties

Spices are substances that can be smelled by the sense of smell or tasted by the sense of taste, and are used to prepare essences or add fragrance directly to products. They can be classified as natural spices and synthetic spices based on their source. Natural spices are further divided into animal spices (such as musk, civet musk) and plant spices (such as rose oil, lavender oil); according to their form, they can be classified as essential oils, refined oils, extracts, resins, tinctures, single isolated spices, powders, etc. Synthetic spices are various single molecules with pure fragrance, classified by functional groups as aldehydes (such as vanillin, citral), ketones (such as dihydrojasmone, musk ketone), acids (such as propionic acid, caprylic acid), alcohols (such as menthol, camphene), esters (such as ethyl acetate), etc.; according to the framework, they can be classified as aliphatic, aromatic, terpene, etc. The preparation methods of natural spices mainly include steam distillation method, pressing method, soaking method, supercritical extraction method, etc.

Essence is a mixture containing two or even dozens of fragrances (sometimes with suitable solvents or carriers) that has a certain aroma. Essence can be classified into daily use essence, edible essence and other-purpose essence according to its use. According to the aroma or fragrance, it can be classified into types such as orange, sweet orange, cream, vanilla, etc. According to the solubility, it can be divided into water-soluble (including alcohol-soluble) and oil-soluble categories. According to the form, it can be classified into liquid (including paste, emulsion) and solid (including powder, block) types. Fixatives are an important component in essence preparation, and their function is to make the aroma components of various single fragrant substances in the essence volatilize evenly, maintain the stability of the aroma and prevent rapid evaporation, and keep the essence with a certain duration of retention effect [10].

The substances contained in essence are quite diverse. They are affected by factors such as temperature, light, and pH. Reactions may occur between fragrant materials and each other, or between fragrant materials and the base material, causing changes in aroma and color, and even generating some harmful substances. When selecting essence, it is necessary to strictly conduct physical and chemical properties and safety tests on the essence and the products after adding fragrance, and consider the compatibility of essence/product, color change of the product, solubility, and reactions between the essence and the base material. 

Application fields

Food flavorings and fragrances, as important food additives, are mainly used in the food industry to create, modify or enhance the flavor of food. Food flavorings are substances added to food to produce, modify or enhance the aroma; food fragrances are concentrated and formulated mixtures composed of food flavorings and food fragrance auxiliaries, which are used to produce aroma. They are used in the food production and processing process, with a relatively small addition amount.

The use of food flavorings and fragrances follows the following principles: they should not cause any health hazards to the human body; they should not mask food spoilage and deterioration; they should not mask the quality defects of the food itself or the processing process or be used for the purpose of adulteration, adulteration, forgery, etc.; they should not reduce the nutritional value of the food; they should minimize the use amount in the food as much as possible while achieving the expected effect.

According to the "Food Safety National Standard - Use Standards of Food Additives" (GB 2760), food flavorings and fragrances are used in various foods in an appropriate amount as needed for production [5-7]. However, the standard clearly stipulates that the foods listed in Table B.1 do not require flavoring and shall not add food flavorings and fragrances, except where otherwise specified by laws, regulations or national food safety standards.

For infant food, there are more strict regulations: any infant formula food with a usage range covering infants aged 0-6 months shall not add any edible flavorings. For larger infant and toddler formula foods, vanillin, ethyl vanillin and vanilla bean extract (extract) can be used, with the maximum usage amounts of 5 milligrams per 100 milliliters, 5 milligrams per 100 milliliters and as needed for production, respectively. Infant cereal supplementary foods can use vanillin, with a maximum usage amount of 7 milligrams per 100 grams.

For import and export procedures, flavorings and fragrances as food additives must comply with the inspection and quarantine requirements such as "Inspection and Quarantine Procedures for Imported and Exported Food Additives - Part 22: Flavorings and Fragrances" (SN/T 2360.22-2009).