Various aromatic plants and spices as well as fruits constitute valuable phytogenic sources. In recent years, the use of
phytogenic compounds has gained momentum for their potential role as natural alternatives to antibiotic growth promoters
(AGP) in animal nutrition. The rather generic term “phytogenic compounds” may refer either to their utilised parts and/or
to their respective plant extracts (e.g. essential oils, oleoresins, and flavonoids). So far, the essential oils (EO) or their main
active principles are the most widely utilised category of plant extracts in animal nutrition (Kamel, 2000; Windisch et al.,
2008; Brenes and Roura, 2010). According to the European Union legislation (EC 1831, 2003), phytogenic compounds have
been categorised as “sensory additives” and in particular as flavouring compounds.