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During ripening, ‘Hass’ avocado skin changes from green to purple/black. Low-temperature storage with a controlled atmosphere (CA) is the most widely used method for avocado storage; however, few studies have simulated this technology and considered the days of regular air (RA) storage prior to CA storage. Herein, the effect of delaying the storage of ‘Hass’ avocado (>30% dry matter) in a CA was examined. Long-term storage conditions (5 °C for 50 days) corresponded to (i) regular air storage (RA), (ii) CA (4 kPa O2 and 6 kPa CO2) and (iii) 10 days in RA + 40 days in a CA and (iv) 20 days in RA + 30 days in a CA. Evaluations were performed during storage and at the ready-to-eat (RTE) stage. Skin color remained unchanged during storage, but at the RTE stage, more color development was observed for fruits stored under CA conditions, as these fruits were purple/black (>50%). At the RTE stage, the anthocyanin content increased, and compared to fruit under RA, fruit under a CA contained a five-fold greater content. A 20-day delay between harvest and CA storage increased the fruit softening rate and skin color development after cold storage, reducing the effectiveness of CA as a postharvest technology for extending storage life.

Sweet cherry may develop surface pitting during prolonged cold storage, and susceptibility among varieties is related to metabolites in response to cold and mechanical damage. This study aimed to evaluate the metabolic changes in sweet cherry fruits subjected to melatonin treatment and induced surface pitting. Melatonin (400 µM) was applied to sweet cherries before pitting induction and then stored at 1 °C for 20 d. Melatonin treatment attenuated the severity of pitting damage during cold storage, with an average severity value of 3.1 for cherries with melatonin and 2.6 without melatonin. In addition, melatonin application appeared to modulate metabolic responses due to the regulation of metabolic pathways related to abiotic stress. Upregulation of different secondary metabolites was observed after 16 h of melatonin treatment and cold storage. Moreover, some metabolites of the sphingolipid and sulfur metabolism were upregulated after 10 d. This research is the first to show that melatonin may influence the response of sweet cherries to cold and mechanical damage.

The choice of rootstock has a significant impact, not only on fruit growth and development, but also on avocado fruit quality and postharvest performance. The objective of this study was to evaluate and compare attributes related to the postharvest quality of Hass avocados from “Mexicola” and “Duke 7” rootstocks grown under similar conditions. This study included two harvests: early (23–26% dry matter) and middle (>26–30% dry matter) per season for the 2016/2017 and 2017/2018 seasons and two storage conditions (regular air (RA) at 5 °C and controlled atmosphere (CA) at 4 kPa O2 and 6 kPa CO2 at 5 °C) for 55 days. The results showed significant differences in firmness, color and vascular and flesh browning between storage conditions; in addition to these last three attributes, the rootstock played an important role. The fatty acid profile did not reveal significant differences between fruit from both rootstocks. Finally, the polar metabolite profiles revealed differences only for the storage condition, not associated to the rootstock, which could affect the postharvest performance of Hass avocado fruit. This study is one of the few available showing the interaction of rootstock/Hass cultivar on fruit quality and postharvest performance.

Avocado consumption and trade are increasing worldwide, with North America and Europe being the main importing regions. Spain is the major European avocado producer (90% of the production), yet it only supplies 10% of the market. Consequently, more than 90% of the avocados consumed in Europe are imported from overseas, mainly from Chile and Peru. In this work, the Life Cycle Assessment (LCA) impact associated with the transport of two avocado supply chains (short (Spanish) and long (Chilean)) and the effect of the fruit origin and distance of both chains on primary and secondary metabolites from harvest to edible ripeness were evaluated using a gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled to diode array detection (LC-DAD) based metabolite analysis. The LCA transport impact of the fresh supply chain from production centers in Chile (Quillota) and Spain (Malaga), and then the distribution to several cities in Europe, suggested road export from Spain to European capitals to have the lowest impact (0.14 to 0.22 kg CO2 eq/kg of avocado). When export from Chile was considered, the option of oceanic freight to European ports closer to final destinations was clearly a better option (0.21 to 0.26 kg CO2 eq/kg) than via the Algeciras port in Spain followed by road transport to final destinations in European capitals (0.34 to 0.43 kg CO2 eq/kg), although the situation could be somewhat different if the avocados are transported from the destination ports in northern Europe to long-distance capitals in other European countries. Fruit origin had a significant impact on avocado primary and secondary metabolites. The conditions of the supply chain itself (10 d in cold storage in regular conditions vs. 30 d cold storage + controlled atmosphere conditions) largely influence the fate of some metabolites that certainly affect the pool of metabolites at edible ripeness. The long-assumed hypothesis that the longer the supply chain the more negative impact on nutritional and functional compounds might not hold in this case, as long as transport conditions are adequate in terms of temperature, atmosphere conditions, and time considering distance from origin to destination.