Effects of Harvesting Date and Storage on the Amounts of Polyacetylenes in Carrots, Daucus carota

Abstract

The amounts of three main polyacetylenes in carrots; falcarinol, falcarindiol, and falcarindiol-3-acetate, were determined by HPLC, during three seasons, in carrots harvested several times per season and at different locations in Sweden. The amounts of falcarindiol first decreased from a relatively high level and then increased later in the harvest season. The amounts of falcarindiol-3-acetate showed similar variations, whereas the amounts of falcarinol did not exhibit any significant variation during the harvest season. During storage the amount of polyacetylenes leveled off, increasing in samples initially low and decreasing in samples initially high in polyacetylenes. The amounts of all polyacetylenes varied significantly due to external factors and between stored and fresh samples. This variation opens up possibilities to achieve a chemical composition of polyacetylenes at harvest that minimizes the risk of bitter off-taste and maximizes the positive health effects reported in connection with polyacetylenes in carrots.

Handbook of Plant Food Phytochemicals

“…For example although high light can increase flavonoid synthesis, high temperature has been reported to decrease anthocyanin synthesis [116]. In carrot levels of polyacetylenes were significantly different in different harvest years indicating a seasonal effect on falcarinol and falcarindiol [81], however no meteorological data is presented and the underlying mechanism is unclear.…”

“…An influence of soil type on phytochemical accumulation including glucosinolates and phenolic compounds is commonly mentioned anecdotally in the literature [24,56,75,81,129,156] and in a study by Jones et al (2007) higher levels of glucosinolates were found in broccoli florets of the cultivar Marathon grown in light clay soils as compared to those grown in sandy loam type soils [75]. However such observations are complicated to interpret as crops grown in different areas will also experience different climatic and other agronomic conditions.…”

“…In the most recent study [81] levels of falcarinol, falcarindiol and falcarindiol-3-acetate in roots of two carrot varieties (Kampe and Bolero) were reported to stabilize during storage with an increase noted in samples that were initially low and a decrease in samples initially high in polyacetylenes [81].…”

“…Levels of both falcarindiol and falcarindiol-3-acetate were found to be significantly higher in small/immature (50-100g) than in large (>250g) carrot roots in an analysis of 6 Nantes type carrot varieties, however levels of falcarinol were unaffected [79]. Similarly, in a three year field study on two carrot varieties (Bolero and Kampe) harvested at different maturity stages (103)(104) days, 117-118 days, 131-133 days, and 146-147 days), maturity had no effect on levels of falcarinol in fresh carrots [81].…”

“…Few studies have been carried out to evaluate the effect of storage on carrot polyacetylenes [62,79,81].…”