Enriched cereal bars are more effective in increasing plasma quercetin compared with quercetin from powder-filled hard capsules
The flavonol quercetin, is one of the major flavonoids found in edible plants. The bioavailability of quercetin in humans may be influenced by the food matrix in which it is consumed as well as by its chemical and physical form. The objective of the present study was to investigate the biokinetics of quercetin from quercetin-enriched cereal bars and quercetin powder-filled hard capsules. In a randomised, single-blinded, diet-controlled cross-over study, six healthy women aged 22–28 years took a single oral dose of approximately 130 mg quercetin equivalents from either quercetin-enriched cereal bars (containing 93·3 % quercetin aglycone plus 6·7 % quercetin-4′-glucoside) or quercetin powder-…
Degradation of heterocyclic aromatic amines in oil under storage and frying conditions and reduction of their mutagenic potential.
Heterocyclic aromatic amines (HAA) were systematically studied concerning their partition behavior in water/oil-systems and their thermostability in different animal derived fats and vegetable oils. Partitioning of IQx-compounds and PhIP in water/oil systems was found to depend on the polarity defined by the molecular structure and on the pH-value of the aqueous phase. In particular, beta-carbolines norharman and harman showed a significant strong lipophilic character at alkaline pH. After heating in frying fats at 130 degrees C, contents of IQx compounds and PhIP were reduced by more than 40% and after heating at 180 degrees C less than 10% of the HAA initial concentration was recovered. B…