Assessment of Glucosinolates in Broccoli by Three Different Methodologies

Three different methodologies were used to assess the glucosinolate content in four broccoli cultivars. The assessment was performed by the thymol, enzyme immobilization and gas liquid chromatography (GLC) techniques. The cultivars used were Green Valiant, Green Duke, Marathon and Samurai. The three techniques demonstrated that Samurai and Green Valiant were the cultivars with the highest content of glucosinolates. It was also evident that, compared to stem and leaves, the floret of the four cultivars exhibited in general the highest amount of this component. Of the tested methodologies, the GLC technique showed the lowest data variability, although this technique was unable to estimate all the glucosinolates present in the broccoli samples because of its poor performance for the quantitation of indole and sulfinyl glucosinolates. In conclusion, the thymol technique appeared the most adequate procedure for the assessment of glucosinolates in broccoli samples.