Ortiz Abel, Echeverría Gemma, Graell Jordi, Lara Isabel
Area de Post-Collita, XaRTA, UdL-IRTA, Lleida, Spain.
J Agric Food Chem. 2009 Jun 10;57(11):4931-8. doi: 10.1021/jf9003576.
Despite the relevance of volatile production for overall quality of apple (Malus x domestica Borkh.) fruit, only a few studies have focused on the effects of calcium treatments on this quality attribute. In this work, 'Fuji Kiku-8' apples were harvested at commercial maturity, dipped in calcium chloride (2%, w/v), stored at 1 degrees C and 92% relative humidity for 4 or 7 months under either air or ultralow oxygen (ULO; 1 kPa of O(2)/2 kPa of CO(2)), and placed subsequently at 20 degrees C. Ethylene production, standard quality parameters, emission of volatile compounds, and the activities of some related enzymes were assessed 7 days thereafter. Calcium concentration was higher in CaCl(2)-treated than in untreated fruit, suggesting that the treatment was effective in introducing calcium into the tissues. Higher calcium contents were concomitant with higher flesh firmness and titratable acidity after storage. Furthermore, calcium treatment led to increased production of volatiles in middle-term stored apples, probably arising from enhanced supply of precursors for ester production as a consequence of increased pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) activities. After long-term storage, higher volatile emission might have arisen also from the enhancement of alcohol o-acyltransferase (AAT) activity, which was increased as a result of calcium treatment. In addition to storage period, the effects of calcium treatment were also partially dependent on storage atmosphere and more noticeable for fruit stored in air.
尽管挥发性物质的产生对苹果（苹果属苹果种）果实的整体品质具有重要意义，但仅有少数研究关注钙处理对这一品质属性的影响。在本研究中，“富士菊八”苹果在商业成熟时采收，浸入氯化钙（2%，w/v）中，于1℃和92%相对湿度下在空气或超低氧（ULO；1 kPa O₂/2 kPa CO₂）环境中储存4或7个月，随后置于20℃下。7天后评估乙烯生成量、标准品质参数、挥发性化合物的释放以及一些相关酶的活性。经氯化钙处理的果实中钙浓度高于未处理的果实，表明该处理有效地将钙引入了组织。储存后，较高的钙含量伴随着较高的果肉硬度和可滴定酸度。此外，钙处理导致中期储存苹果中挥发性物质的产生增加，这可能是由于丙酮酸脱羧酶（PDC）和乙醇脱氢酶（ADH）活性增加，从而增强了酯类生成前体的供应。长期储存后，较高的挥发性物质释放量也可能源于钙处理使醇酰基转移酶（AAT）活性增强。除储存时间外，钙处理的效果还部分取决于储存气氛，且对空气中储存的果实更为明显。
