Evaluation of the Antioxidant Activity and Phenolic Content of Chamomile (Chamomilla recutita L) Extract

Nowadays, there is a great intetest to use natural additives in food products especially compunds that are extracted from plants. Chamomile (Matricaria chamomilla L.) is an annual herbaceous flowering plant native to Europe. It has been used traditionally as a medicinal and pharmaceutical preparation due to its anti-inflammatory and antispasmodic properties.
The amount of polyphenolic compounds and radical-scavenging activity of the aqueous extract of chamomile were studied under different conditions of heating, pH alterations and storage.
Heat treatment of 70-120°C at pH of either 5.6 or 2.6 for 5 and 15 minutes did not influence the phenolics content. However, acidification of the extract from the inherent value of 5.6 to 2.6 decreased the polyphenols content by 10%. The antioxidant activity of the extract decreased due to heating at 70, 80 and 90°C and the higher the heating temperature and the longer the heating duration, the lower was the antioxidant activity of the heat-treated extract. The amount of polyphenols in the extract with the inherent pH of 5.6 was increased over 25-day storage period that was attributed to the release of some phenolic compounds being bound to other compounds.
The results of this study showed that polyphenols present in aqueous extract of chamomile are resistance to thermal process. But, the antioxidant activity of extract was reduced as the result of heating. However, it can be concluded that the phenolic compounds of chamomile extract had a high resistance to heat and showed a significant antioxidant activity after pasteurization process. Moreover, the phenolic compounds of the extract were stable in acidic pH during long-term maintenance.