Establishment of a criterion to determine the optimal harvest date of 'Gala' apples based on consumer preferences

Abstract

In order to define a rational criterion to harvest 'Gala' apples based on consumer preferences, an experimental study was carried out with two objectives: (1) to determine the most important fruit quality parameters and their optimal values at harvest to satisfy 'Gala' apple consumers after long term storage, and (2) to identify groups of consumers with different organoleptic preferences and to establish the optimum harvest date depending on the target market. A sample of fruits from twelve commercial orchards of Girona and Lleida were harvested every week for six weeks. At harvest time, fruit quality parameters (background colour, firmness, starch index, soluble solids content and acidity) were measured, and after storage, a consume preference consumer survey was carried out. Starch index and background colour were the best predictors of optimum harvest date in 'Gala' apples based on average consumer preferences. Four groups of consumers with different organoleptic preferences were found. 26% of people preferred firm, crisp and acid apples. 24% of consumers preferred very ripe apples, with a softer texture and a high level of soluble solids. 45% of consumers preferred firm apples with not very high level of soluble solids, and the 5% preferred very sweet firm apples. Excluding the two first groups of people who could be satisfied with other apple cultivars on the market ('Granny Smith', 'Red Delicious' and 'Starking', among others), apples harvested when the starch index was between 5 and 7 on a scale of 1 to 10, and a skin background colour of F2 to F3 on the CTIFL scale, were the apples most preferred by consumers.