Falagán Natalia, Miclo Tiana, Terry Leon A
Plant Science Laboratory, Cranfield University, Cranfield, United Kingdom.
Front Plant Sci. 2020 Mar 17;11:221. doi: 10.3389/fpls.2020.00221. eCollection 2020.
Blueberries ( L.) are highly valued for their health-promoting potential, yet they are extremely perishable. Controlled atmosphere (CA) strategies reduce blueberry respiratory metabolism, slowing down senescence. However, the sudden change of atmosphere could elicit a physical abiotic stress in the fruit, negatively affecting quality. We propose an innovative approach based on controlled graduation to slowly reach optimum gas storage conditions as an alternative to standard CA. For two consecutive seasons, "Duke" blueberries were subjected to four different storage conditions: control (air); standard CA (sudden exposure to 5 kPa O and 10 kPa CO across the experiment); GCA3 and GCA7 (gradually reaching 5 kPa O and 10 kPa CO in 3 and 7 days, respectively). Fruit were stored for 28 days at 0 ± 0.5°C. Real-time respirometry provided an in-depth insight to the respiratory response of blueberries to their gas environment. Blueberries subjected to the graduated application of CA (GCA) treatments had a lower steady-state respiration rate compared to control and standard CA fruit. This indicated a reduction in metabolic activity that positively impacted quality and storage life extension. For example, GCA3 and GCA7 blueberries had a 25% longer storage life when compared to control, based on reduced decay incidence. In addition, GCA fruit were 27% firmer than control and CA fruit after 28 days of cold storage. GCA3 had a positive effect on maintaining individual sugars concentrations throughout the experiment, and both GCA treatments maintained ascorbic acid content close to initial values compared to a decrease of 44% in the control fruit at the end of the experiment. This work provides a paradigm shift in how CA could be applied and a better understanding of blueberry physiology and postharvest behavior.
蓝莓（L.）因其促进健康的潜力而备受重视，但它们极易腐烂。气调（CA）策略可降低蓝莓的呼吸代谢，减缓衰老。然而，气氛的突然变化可能会在果实中引发物理非生物胁迫，对品质产生负面影响。我们提出了一种基于控制渐变的创新方法，以缓慢达到最佳气体储存条件，作为标准气调的替代方法。在连续两个季节中，“公爵”蓝莓被置于四种不同的储存条件下：对照（空气）；标准气调（在整个实验过程中突然暴露于5 kPa氧气和10 kPa二氧化碳）；GCA3和GCA7（分别在3天和7天内逐渐达到5 kPa氧气和10 kPa二氧化碳）。果实于0±0.5°C下储存28天。实时呼吸测定法深入了解了蓝莓对其气体环境的呼吸反应。与对照和标准气调处理的果实相比，采用渐变气调（GCA）处理的蓝莓具有较低的稳态呼吸速率。这表明代谢活性降低，对品质和延长储存寿命产生了积极影响。例如，基于腐烂发生率降低，GCA3和GCA7处理的蓝莓与对照相比，储存寿命延长了25%。此外，冷藏28天后，GCA处理的果实比对照和气调处理的果实硬27%。在整个实验过程中，GCA3对维持单个糖浓度有积极作用，与实验结束时对照果实中维生素C含量下降44%相比，两种GCA处理均使维生素C含量接近初始值。这项工作在气调的应用方式上实现了范式转变，并增进了对蓝莓生理学和采后行为的理解。
