Coffee By-Products and Chitosan for Preventing Contamination for Botrytis sp. and Rhizopus sp. in Blueberry Commercialization

In blueberry storage, non-biodegradable synthetic plastic packaging is used for commercializing this product. The fungi Botrytis sp. and Rhizopus sp. can cause significant losses in postharvest blueberry commercialization. Consequently, the formulations of degradable polymeric based on polylactic acid (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) 60/40 (PP) with coffee parchment (CP), green coffee bean oil (GCBO), chitosan solution (Ch), chitosan nanoparticles (ChNp), and nanostructured coating (NC) were used to develop biodegradable polymer matrix (PM). Caffeine and hexadecanoic acid were identified as principal compounds in GCBO, and the principal compounds in CP were flavonoids, terpenes, and lignans. The 100% mycelial growth inhibition to Botrytis sp. and Rhizopus sp. was observed using GCBO, Ch, ChNp, and NC in high concentrations. GCBO inhibited 100% of spore production in both fungi at all evaluated doses. In the in vivo tests, when compared to the control, the better treatments were: CP for Botrytis sp., with an incidence of 46.6% and a severity of 16%; and Ch for Rhizopus sp., with an incidence of 13.3% and a severity of 0.86%. The PM in the culture medium presented a fungistatic effect. The principal inhibition of mycelial growth (63%) on Botrytis sp. was with PLA/PBAT+NC (PP+NC), and (100%) was observed with PLA/PBAT+CP+NC (PPCP+NC), PP, and PP+NC on Rhizopus sp. Coffee by-products and PM have potential for the control of postharvest fungi in fruits and vegetables.