Acta Scientiarum Polonorum Technologia Alimentaria

Background. Borage is an edible flower with a very limited shelf-life (approx. 1 day). After harvest, flowers dry and shrink rapidly and become darker. Extending the shelf life of borage will make it more appealing for commercialization and it will enable borage growers to expand their market. The aim of the present work is to evaluate the effect of three post-harvest technologies.

Material and methods. Freeze-drying, hot air convective drying and alginate edible coating were applied to borage petals, and the visual appearance, water activity (aw) and weight loss was evaluated.

Results. Hot air-dried samples had an unsatisfactory visual appearance. Freeze dried flowers were less shrunken and dried while showing the lowest aw (0.25 ±0.01). Alginate coated flowers had a good visual ap- pearance, like fresh flowers, which was maintained during refrigerated storage (for 5 days), four days longer than those which were uncoated. Nevertheless, the flowers became fragile and it was difficult to handle them without causing damage.

Conclusion. Freeze drying may be applied to produce dried borage flowers for infusions, while alginate coat- ing is a promising treatment to increase shelf-life subject to further development.