showed that sweetness was high and negatively related to the total glucosinolate
content, which in turn coincided closely with bitter and pungent taste.
Hydroxycinnamic acids and flavonoids had a slight relationship with the sensory
traits evaluated in turnip tops. Therefore, it’s worth pointing out that flavonoids
kaempferol-3-O-(caffeoyl)sophoroside-7-O-glucoside and quercetin-3-O-
(caffeoyl)sophoroside-7-O-glucoside displayed correlations highest than R=0.60 for leaf
and stalk firmness (once again negatives) and for taste traits (acid, salty, bitter and
aftertaste persistence). The highest coefficient correlation was found between salty taste
and quercetin-3-O-(caffeoyl)sophoroside-7-O-glucoside (R=0.82). The highest
difference between turnip greens and turnip tops was found in the hydroxycinnamic
acids content. Turnip greens had 27 m g-1 of hydroxycinnamic acids concentration and
turnip tops 19.3 m g-1, which can partially explain the less importance of this
compounds on the flavor of turnip tops.
As summary, indolic and aromatic glucosinolates seem to be more related to
traits indicative of texture while all glucosinolate types (indolic, aliphatic and aromatic)
seems to affect considerably flavor traits, mainly bitterness, acid taste and aftertaste.
Selection of sensorial traits
Simple correlation coefficients among all sensory traits were calculated to
determine which trait gives a better measure of sensorial value in turnip greens and turnip
tops (Table 7). Two attributes related to product appearance, i.e. aroma intensity and
leaf brightness and one trait related to preference, i.e. sharpness, were not correlated
with any other trait. Therefore, these traits have not been useful to describe the flavor
attributes of turnip tops and turnip greens but, depending on the consumer preferences
may play a main role in the evaluation of the products.