S23 - Session P2 - Impact of shocks and vibrations on the strawberry quality in the supply chain

Authors: Sophie Annibal *, Ellyn Dubecq, Jean-Baptiste Nolot

During a road transport, strawberries are subject to two types of mechanical stress: shocks, mainly during load breaking and handling operations, and vibrations, in the truck. The aims of this study were to evaluate the influence of these stresses on strawberry quality and to identify adapted packaging to limit fruit losses. Shocks and vibrations were recorded on 8 logistical circuits representative of long-distance strawberry transport in France. These data were then synthesized and used in simulators to reproduce the pattern in laboratory in order to follow fruit quality evolution, using a degradation index. The recorded shocks in real supply chain were mostly very short, between 2 and 8 milliseconds, with intense accelerations of up to 20 G. In the 0-20 G range, out of 20 'Gariguette' strawberries tested under punnet packaging conditions, 37% were marked just after the shock and 72% two days later. Under conditions of packaging in a single-row mini-tray, the quality was better preserved with only 10% of the fruits were marked just after the shock and 33% two days later. Two vibration simulation paths, medium and severe, were applied to 3 strawberry batches and 4 types of packaging (single-row mini-trays, punnets of 250 g placed in crates made of wood, plastic or cardboard). Vibration damages were clearly visible after 3 days at 5°C and depended on the sensitivity of the strawberry batch, the severity of the circuit, and the packages material (strawberry in plastic crates were more damaged than those in mini-trays, wooden and cardboard crates). The vibration amplification coefficient of plastic crates, between the bottom and the top of the pallet, was at least 4 times higher than other material. However, the impact on the quality of the strawberries placed on the top of the pallet has not been showed in this trial.