Bioactive phenols from feverfew may boost functional drinks: Study
The research, published in Journal of Functional Foods, tested the stability of phenol rich infusions of feverfew in order to assess the infusions ability to perform as a functional ingredient in healthy food and drink formulations.
“Feverfew (Tanacetum parthenium) is a medicinal plant that has been used traditionally to treat various conditions including prophylaxis of migraine headaches, relief of pain and inflammation from arthritis,” said the ressearchers, led by senior author Professor Dolores O’Riordan, of the Institute of Food and Health at University College Dublin, Ireland.
However, prior to incorporation into an acidic product (such as a functional juice drink), O’Riordan and co-workers explained that the storage and stability of such infusions needs to be examined – as they may affect the potency and consumer acceptability of the final product.
Functional phenols
Prof O’Riordan and her colleagues said the incorporation of bioactive compounds into functional foods is a rapidly growing market. They noted that in the functional food category, functional beverages are the fastest growing segment, “with strong consumer interest in foods with energy enhancing, anti-ageing, relaxing and general well being properties,” in addition to a demand for traditional products and beverages with organic plant ingredients.
Previous studies have suggested that extracts of feverfew could be a rich source of phenolic compounds, which may be used for the enrichment of foods and beverages – especially to enrich the phenolic content of functional beverages.
The authors noted, however that little is known about the stoarage stability of feverfew infusions, post extraction. They said that such information is important to know how the bioactive ingredients will perform in a functional drink
The new study evaluated the effect of pH on the degradation of the phenolic compounds at storage temperatures of 5 and 22 °C, in acidified aqueous solutions. The pH range studied was representative of that found in non-alcoholic beverages.
Stability study
Feverfew powder (5.0 g) was extracted in 200 ml of distilled water at 100 °C for 10 minutes, with the aim of maximising the bioactive constituents and minimising polyphenol oxidase (PPO) activity.
O’Riordan and her colleagues reported that the colour of the infusions at acidic pH levels (2.9, 3.7 and 4.6) did not change significantly with time or storage temperature.
However, they observed storage temperature to have “a major influence” on the colour evolution of infusions at pH 6.0 with storage time (up to nine months).
Storage temperature also had a major effect on the chroma (saturation) of the infusions. The researchers found storage at 22 °C caused a significant decrease in the chroma – from 11.5 to 1.0 after 56 days of storage. Whereas they found storage at 5 °C caused only a slight decrease, from 11.5 to 8.7.
“Phenolic content of feverfew infusions at pH 2.9–6.0 stored at 5 °C was not significantly affected after 56 days of storage. In contrast, the phenolic content of the infusions (pH 6.0) stored at 22 °C showed a significant decrease from 73.1 to 43.6 mg/100 ml GAE after 56 days of storage,” said the authors.
“Therefore, refrigerated storage of mildly acidic infusions (pH 4.6) was found to be the optimum for colour retention, phenolic and parthenolide content with a shelf-life of approximately 4 months,” said O’Riordan and her co-workers.
Source: Journal of Functional Foods
Published online ahead of print, doi: 10.1016/j.jff.2011.01.004
“Feverfew as a source of bioactives for functional foods: Storage stability in model beverages”
Authors: E.N. Marete, J.C Jacquier, D. O’Riordan
