Peat replacement is an increasing demand in containerized and transplant production, due to the environmental constraints associated to peat use. However, despite the wide information concerning the use of alternative materials as substrates, it is very complex to establish the best materials and mixtures. This work evaluates the use of mixture design and surface response methodology in a peat substitution experiment using two alternative materials (green compost and palm fibre trunk waste) for transplant production of tomato (Lycopersicon esculentum Mill.); melon, (Cucumis melo L.); and lettuce (Lactuca sativa L.) in organic farming conditions. In general, the substrates showed suitable properties for their use in seedling production, showing the best plant response the mixture of 20% green compost, 39% palm fibre and 31% peat. The mixture design and applied response surface methodology has shown to be an useful approach to optimize substrate formulations in peat substitution experiments to standardize plant responses.

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Maintaining the cold chain during long-term storage is important for the preservation of fresh food quality. Arils are usually extracted from freshly harvested pomegranates or after short storage period. Nevertheless, pomegranate fruit may be stored for several weeks before being marketed as ready-to-eat aril (REA). In this study, the effect of different postharvest storage periods (30, 45, and 60 days) and temperatures (2°C and 6°C) on the quality of arils after storage of fruit and then after 10 days storage were investigated. The fruit storage period significantly affected total phenols, antioxidant activity, and vitamin C content of REA from stored fruit and after 10 days storage. Color, anthocyanins, and organic acids of REA varied significantly with the fruit storage period mainly after 10 days. The highest changes were observed after 60 days of fruit storage period. Generally, storage temperature has no effect on bioactive properties and has minimal influence on REA after 10 days storage period. Sensory and volatiles changes were affected not only by storage temperature but also by long storage duration. Thus, aroma profile was markedly separated in heatmap by storage time and temperature. Similar aroma profiles for REA extracted immediately after each storage period or from freshly harvested fruit were distinguished. However, changes were observed for stored fruit after 10 days storage at 6°C, with more abundance of terpenes such as (Z)β-farenesene, (E)α-bergamotene, and α-pinene. PracticalapplicationsReady-to-eat arils (REA) quality is generally affected by several postharvest treatments and conditions. This study used a combination of storage temperatures and duration of "Gabsi" pomegranate fruit to determine the quality of arils after shelf-life.Results of aril sensory analysis showed that the overall flavor and appearance were highly rated in aril when the fruit was stored for 2 months at 2°C. Similarly, results of instrumental measurements showed that the fruit could be stored for 2 months at 2°C without significant reduction in compounds that are beneficial for health and aril color. Storing fruit for 60 days at 6°C led to a reduction in overall quality and changes in aroma profile of REA. The outcomes of this study suggest that a storage period Howtocitethisarticle: Ben Amara M, Abdelli S, De Chiara MLV, et al. Changes in quality attributes and volatile profile of ready-to-eat "Gabsi" pomegranate arils as affected by storage duration and temperatures.