Quantitation of Chlorophylls and 22 of Their Colored Degradation Products in Culinary Aromatic Herbs by HPLC-DAD-MS and Correlation with Color Changes During the Dehydration Process

Abstract

Chlorophylls and their green and olive-brown derivatives were successfully separated from culinary herb extracts by HPLC with photodiode-array and mass spectrometry detection. The method involved a ternary gradient elution and reverse-phase separation conditions capable of resolving 24 different pigments (2 chlorophylls and 22 of their derivatives) of different polarities within 28 min. The method was applied to monitor color changes in 50 samples of culinary aromatic herbs subjected to five different drying treatments. Of the 24 pigments, 14 were key to understanding the differences between the primary degradation pathways of chlorophyll a and chlorophyll b in culinary herbs during drying processes. A color degradation ladder based on the total molar percentage of all the remaining green pigments was also proposed as a tool to measure the impact of drying treatments on aromatic herb visual aspects.

Evaluation of the impact of chlorophyll removal techniques on polyphenols in rosemary and thyme by‐products

“…Apart from trace amounts of chlorophyll a and b , other degradation products of chlorophyll that were not identified and quantified in the present study could have led to this pigmentation. Those include the epimers a and b of chlorophylls a and b respectively, as well as additional derivatives including pheophorbide, pyropheophorbide, and pyrochlorphillide (Lafeuille et al, ). However, this method can be still employed for eliminating the green pigmentation of plant extracts before food applications and chromatographic analysis when the target compounds are not phenolic diterpenes or nonpolar and moderately polar compounds.…”

“…In regard to the different decolorization methods (Tables 5 and 6), pheophorbide, pyropheophorbide, and pyrochlorphillide (Lafeuille et al, 2014). However, this method can be still employed for eliminating the green pigmentation of plant extracts before food applications and chromatographic analysis when the target compounds are not phenolic diterpenes or nonpolar and moderately polar compounds.…”

Impact of steam treatment on shelf‐life stability of a xanthone‐rich green herbal tea (Cyclopia maculata Andrews Kies) – identifying quality changes during storage

“…Various factors contribute to chlorophyll degradation, including high temperatures, relative water activity, and integrity of cell membranes. [16][17][18] Chlorophyll breaks down to pheophytin faster at higher water activities (> 0.32). 17 Indeed, a significant negative correlation was found between TC and moisture content.…”

A review on analytical methods for the determination of natural colorants (green) in food commodities and beverages

“…1a). Among the various food processing methods, dehydration promotes minimizing water related problems of the product and freeze-drying among sun-drying, oven-drying and freeze-drying are used preferentially to preserve green color [31]. Hence, the freeze dried system is less drastic than hot-air-dried one, because the higher amounts of oxidized derivatives pyroderivatives, pheophytinization, and epimerization take place in hot-air-dried food materials.…”