Each analytical sample (2 g, in triplicate) added with 1.0 g of magnesium hydroxide carbonate to neutralize any organic acids and internal standard (-apo-8-carotenal for fruits or echEach analytical sample (2 g, in triplicate) added with 1.0 g of magnesium hydroxide carbonate to neutralize any organic acids and internal standard (-apo-8-carotenal for fruits or echinenone for green vegetables) was extracted four times with
50mL MeOH:THF (1:1, v/v) containing BHT (0.01%),inenone for green vegetables) was extracted four times with 50mL MeOH:THF (1:1, v/v) containing BHT (0.01%),