Interest in the flavour components of garlic led to the isolation of some volatile constituents from garlic oil, mainly diallyl sulphide and smaller amounts of diallyl trisulphide and diallyl polysulphide, by Wertheim in 1884-1885 and later Semmler, in 1892. Rundqvist (1909) was the first to attempt to isolate the basic principle in garlic which gives rise to diallyl sulphide when garlic is crushed, while Cavallito and Bailey isolated allicin by ethanol extraction and steam distillation in 1944. 1
The major effort in the elucidation of the flavour precursors of intact onion and garlic tissue came through the efforts of Virtanen and co-workers in Finland, and the synthesis work of Carson in the United States of America, during the period 1955-1970. During this same period Schwimmer, Mazelis and others worked extensively on the enzymes involved in converting the flavour precursors to the active compounds. The general features of the biosynthesis of the flavour constituents, their enzymatic conversion to primary products, and the rearrangement, decomposition and interaction into the secondary products responsible for the flavour and odour of garlic are generally understood and agreed.
One of the outstanding features of the chemical composition of garlic and of Allium species in general, is the large amount of organically bound sulphur. The number of sulphur compounds found in garlic is much larger than that found in most organisms and one of the reasons for the attention they have received is their potential flavour and antibiotic properties. 2
The world-wide production of garlic (approximately 7 million tons) is concentrated for beyond 80% in the Asian countries (above all China, with approximately 60%), while Europe concurs with little more than 6%. Between the European countries, the greater producer is Spain, followed by France and Italy. The cultivations in our country, Italy, are localized mostly in Campania (21% of the national production), Veneto (18%), Emilia Romagna (17%), Sicily (13%), Puglia (9%) and Abruzzi (7%).
This website studies the development of flavour and odour in garlic through the biosynthesis of flavour precursors, their enzymatic conversion to primary flavour compounds and the final breakdown to the secondary compounds that typify garlic odour and flavour. Besides that, the website contains some information about the agronomy of this plant and the effects of its organic compounds on the human health.