Extending the shelf life of fresh-cut eggplant with a soy protein–cysteine based edible coating and modified atmosphere packaging

• A SPI–Cys edible coating helped control enzymatic browning of fresh-cut eggplants.
• An increase of Cys content from 0.5 to 1% extends the shelf life to 8–9 storage days.
• Conventional MA packaging conditions induced browning of fresh-cut eggplants.
• High O2 MA packaging and atmospheric conditions helped maintain the visual quality.

The effect of a soy protein-based edible coating with antioxidant activity, and conventional and superatmospheric modified atmosphere (MA) packaging, on the quality of fresh-cut ‘Telma’ eggplants, was evaluated during storage. In a first experiment, eggplant pieces were dipped in either a coating composed of soy protein isolate (SPI) and 0.5% cysteine (Cys), or water as an uncoated control. Samples were packed in trays under atmospheric conditions to reach a passive MA (MA-P) or two gas mixtures (MA-A: 15 kPa CO2 + 5 kPa O2; MA-B: 80 kPa O2) and were stored at 5 °C. Atmospheric conditions were used as the control conditions (Control). The coated samples packed under MA-B and Control conditions resulted in the highest whiteness index (WI) values during storage, whereas MA-A did not improve the shelf-life of minimally processed eggplants and had the lowest WI values. The MA-B and atmospheric control conditions helped to maintain firmness, whereas the coating helped to maintain the weight loss under MA-A and MA-B. The maximum commercial shelf-life was reached on day 6 for the coated samples packed under atmospheric conditions. In a second experiment, the commercial shelf-life of fresh-cut eggplants was extended to 8 and 9 storage days by increasing the Cys content in the edible coating from 0.5 to 1% under MA-B and Control storage conditions, respectively.

Soy protein-based edible coating and modified atmosphere packaging to extend the shelf life of fresh-cut Telma’ eggplant.Figure optionsDownload as PowerPoint slide