Polyphenols are a class of micronutrients associated with beneficial health effects including positive changes to gut microbiome and “protection against development of cancers, cardiovascular diseases, diabetes, osteoporosis and neurodegenerative diseases.”
The Phenol Explorer is a web-searchable database that can be accessed to explore the polyphenol contents in foods.
“Phenol-Explorer is the first comprehensive database on polyphenol content in foods. The database contains more than 35,000 content values for 500 different polyphenols in over 400 foods. These data are derived from the systematic collection of more than 60,000 original content values found in more than 1,300 scientific publications. Each of these publications has been critically evaluated before inclusion in the database. The whole data on the polyphenol composition of foods is available for download.
Release 2.0 of Phenol-Explorer added comprehensive data on polyphenol metabolism. Pharmacokinetic data on 380 metabolites identified in biofluids after the consumption of polyphenol-rich sources are presented. These data have been extracted from 236 publications and originate from 221 intervention studies in human subjects and experimental animals.
Release 3.0 of Phenol-Explorer introduces data on the effects of food processing and cooking. Retention factors describe changes in polyphenol content upon food transformation and can be used to estimate composition of processed foods when laboratory measurements are missing and the data are absent from food composition tables. Retention factors are available for 155 foods, 139 polyphenols, and 35 processes. They are derived from 129 publications. “- phenol-explorer
The Phenol-Explorer web database (http://www.phenol-explorer.eu) was recently updated with new data on polyphenol retention due to food processing. Here, we analyze these data to investigate the effect of different variables on polyphenol content and make recommendations aimed at refining estimation of intake in epidemiological studies.
Methods and results
Data on the effects of processing upon 161 polyphenols compiled for the Phenol-Explorer database were analyzed to investigate the effects of polyphenol structure, food, and process upon polyphenol loss. These were expressed as retention factors (RFs), fold changes in polyphenol content due to processing. Domestic cooking of common plant foods caused considerable losses (median RF = 0.45–0.70), although variability was high. Food storage caused fewer losses, regardless of food or polyphenol (median RF = 0.88, 0.95, 0.92 for ambient, refrigerated, and frozen storage, respectively). The food under study was often a more important determinant of retention than the process applied.
Phenol-Explorer data enable polyphenol losses due to processing from many different foods to be rapidly compared. Where experimentally determined polyphenol contents of a processed food are not available, only published RFs matching at least the food and polyphenol of interest should be used when building food composition tables for epidemiological studies.