Effects of passive and active modified atmosphere packaging conditions on quality parameters of minimally processed table grapes during cold storage

BACKGROUND: Table grape is a non-climacteric berry, sensitive to water loss and gray mold during postharvest storage. OBJECTIVE: To assess the effect of passive and active modified atmosphere packaging on quality parameters of minimally processed table grapes. METHODS: 'Red Globe' minimally processed table grapes were dipped in a sodium hypochlorite solution and irradiated with ultraviolet-C, before being packaged in a rigid polypropylene boxes, sealed with a micro perforated polypropylene film (PP) or a continuous polyethylene film, with: a) 5% O-2 + 15% CO2 + 80% N (PET1); b) 20% CO2 + air (PET2). Samples were stored at 5 degrees C for 21 days plus and additional 6-day period at 20 degrees C to simulate shelf-life. RESULTS: No chemical and sensory changes during storage occurred in fruit sealed in PP packages. The high in-package CO2 partial pressure which increased in PET1 and PET2 combined with the reduced concentration of O-2, increased decay incidence, stimulated anaerobic respiration, hastened soluble sugars degradation, produced higher weight loss and altered sensory quality. CONCLUSIONS: Quality of minimally processed 'Red Globe' was better maintained in PP packaging where air-composition was not changed than in PET1 and PET2 where toxic levels of CO2 and reduced tension of O-2 hastened quality loss and increased decay incidence.