Poly(lactic acid)/polycaprolactone nanofibrous packaging containing different functional agents for blackberry...

Area of Science:

• Food Science
• Materials Science
• Agricultural Science

Background:

• Postharvest losses in blackberries are substantial, driven by microbial spoilage and physiological deterioration.
• Active packaging offers a promising strategy to mitigate these losses and extend shelf-life.
• Nanofibrous films provide a versatile platform for incorporating active agents to enhance food preservation.

Purpose of the Study:

• To develop and evaluate electrospun nanofibrous films incorporating various active agents for blackberry preservation.
• To compare the efficacy of different active agents, including essential oils, phenolic acids, microbial antagonists, and plant growth regulators, within a poly(lactic acid)/polycaprolactone (PP) nanofilm matrix.
• To assess the impact of these active agents on the physical, chemical, and antimicrobial properties of the nanofilms and their performance in extending blackberry shelf-life.

Main Methods:

• Preparation of poly(lactic acid)/polycaprolactone (PP) nanofibrous films loaded with oregano essential oil (OPP), chlorogenic acid (CPP), natamycin (NPP), and methyl jasmonate (MPP).
• Evaluation of antimicrobial activity against common bacteria and fungi, and assessment of mechanical, thermal, water contact angle, and water permeability properties of the nanofilms.
• Investigation of active agent release, antioxidant activity, and biosafety of the developed nanofilms.
• Application of selected nanofilms to blackberries during postharvest storage to evaluate their effect on appearance, decay rate, weight loss, and softening.

Main Results:

• The addition of active agents altered the mechanical properties of the nanofilms, generally decreasing tensile strength while increasing elastic modulus and elongation at break.
• Most active agents did not significantly affect thermal stability, but some variations were observed in water contact angle and permeability (notably for NPP and MPP).
• The OPP nanofilm demonstrated superior performance in inhibiting blackberry deterioration, showing the lowest impact on appearance, 'red small drupelets' phenomenon, decay rate, weight loss, and softening compared to other treatments.
• All tested nanofilms exhibited controlled release of active agents, antioxidant activity, and biosafety.

Conclusions:

• Poly(lactic acid)/polycaprolactone (PP) nanofibrous films incorporating active agents can effectively enhance blackberry postharvest quality.
• Oregano essential oil/PP (OPP) nanofilms were most effective in extending blackberry shelf-life by significantly reducing spoilage and maintaining overall quality attributes.
• Active packaging using OPP nanofilms presents a viable strategy for improving the storage stability and marketability of fresh blackberries.