Impact of Production Methods and Storage Time on the Bioactive Compounds and Antioxidant Activity of Confitures Made from Blue Honeysuckle Berry (Lonicera caerulea L.)

The blue honeysuckle berry is a fruit known as a rich source of many bioactive substances with proven health-promoting effects. Due to its sour taste with a noticeable hint of bitterness, fruits of this plant are rarely consumed and the consumer prefers the processed form. The purpose of this study was to evaluate the effect of the cooking method on the biological quality of honeysuckle berry confiture. The selected recipe was used to make confiture in a vacuum evaporator using lowered pressure and in a thermomix vessel under atmospheric pressure. Then, the content of the chosen compounds and antioxidant activity of the two types of confitures were compared. The confitures were analyzed right after production and through 180 days of refrigerated storage. The pH, TA and TSS parameters remained unchanged regardless of the production process and storage time. Ascorbic acid, polyphenol and anthocyanin concentrations were greater in the confiture from vacuum cooking. Also, the same confiture showed a lower rate of degradation of bioactive substances during storage. The antioxidant activity of the two types of confiture was significantly different shortly after production, but equal at the end of 180-day storage. HMF content was four times higher in confitures cooked under atmospheric pressure than under vacuum. The confiture made from the honeysuckle berry was very rich in bioactive compounds, especially polyphenols. Vacuum cooking proved to be the best method for confiture production as a result of lower temperatures used and less aeration of the mass.