The determination technique of the geographic origin of Welsh onions by mineral composition and perspectives for the future

Scientific techniques for determining the geographic origin of agricultural products have attracted considerable attention in recent years. The most popular origin-determining technique is based on the composition of inorganic elements, and the technique has been applied to Welsh onions (Allium fistulosum L.). The technique on Welsh onions has been developed and compiled in a manual for monitoring market merchandise earlier than other origin-determining techniques in Japan. This technique makes use of chemometric analysis on concentration ratios of 19 elements (Na, P, K, Ca, Mn, Fe, Cu, Zn, Sr, Ba, Co, Ni, Rb, Mo, Cd, Cs, La, Ce, and Tl) to Mg to determine whether the geographic origin of Welsh onions sold in Japan is Japan or China. The technique is quite practical in that it can screen geographic origin within 2 days by the analysis of inorganic elements by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry.