The effect of gelatin-based edible coating incorporated with Mentha pulegium essential oil (MEO) on physicochemical (pH, titratable acidity (TA), weight loss, total soluble solids (TSS), and total phenolic content (TPC)), microbiological (total aerobic mesophilic flora (TAMF) and yeasts and moulds (YM)), and sensorial (color and firmness) characteristics of strawberries stored under refrigeration was studied. Strawberries were coated with gelatin alone (4%) and/or gelatin combined with two concentrations (0.5 and 1%) of MEO and stored at 4°C for 13 days. Gelatin coating and MEO combination significantly inhibited total flora and moulds and yeasts with comparison to control (uncoated strawberries) and had better hygienic quality at the end of storage. The effect was MEO concentration dependent. Our results also showed that the bioactive coating used in this investigation slowed down changes in pH, TA, weight loss, TSS, firmness, TPC, and color of strawberries. Gelatin coating incorporated with MEO at 1% protected at least 60% of strawberries from deterioration after 13 days of storage and could be used as bioactive packaging to prolong the shelf life and an alternative of pesticides use.

We have carried out our study on the chemical composition and antimicrobial activity of Thymus vulgaris and Origanum compactum essential oils that were harvested in the northeast of Morocco. Carvacrol was the major component in the two investigated essential oils. A high antimicrobial activity has been shown on all tested bacterial strains. The effect of the incorporation of these two essential oils at concentrations of 0.05% and 0.1% on physicochemical, microbiological and sensorial characteristics of goat fresh cheese stored at 8°C has also been studied. No significant differences have been showed between control and aromatized cheeses with respect to pH, titrable acidity, dry matter, lactic acid bacteria and aerobic mesophylic flora. However, coliforms were completely inhibited by the presence of both essential oils from the first storage day. Shelf life estimation has been determined by the reparameterized Gompertz equation by monitoring the growth of molds and yeasts. Origanum compactum essential oil was more effective on extending the shelf life of fresh goat cheese than Thymus vulgaris essential oil. Nevertheless, the aromatized cheese with Thymus vulgaris essential oil was the most appreciated by the tasting panel.