No abstract

Degreening treatment is normally applied to early-season citrus varieties grown in the Mediterranean area in order to enhance the external colour when fruits have already reached internal maturity. Despite profound knowledge about the effect of ethylene on the physico-chemical quality of citrus fruit, less is known about its effect on consumers' expectations in the supermarket or consumer quality perceptions when they eat such fruit. In this study, three mandarin cultivars ('Owari', 'Clemenules' and 'Oronules') with two initial colours at harvest, and one orange cultivar, 'Navelina', were submitted to the degreening treatment under commercial conditions. The effect of treatment on both external and internal qualities perceived by consumers was evaluated. The main physico-chemical parameters were also determined. The degreening treatment slightly affected firmness, total soluble solids or acidity level in 'Owari' and 'Navelina'. However, sensory triangle tests, in which 100 to 122 consumers compared the internal quality of degreened fruit and control fruit, did not show significant differences between treatments for any of the studied cultivars. A survey based on images of citrus fruit was responded by 340 consumers; it showed that the degreening treatment strongly affected consumers' maturity expectations, which resulted in improved fruit liking expectations and increased the number of consumers willing to buy. The extent of this effect depended on the initial colour of the fruit submitted to degreening. In order to improve liking expectations, fruit should arrive on the market with an external colour index (CI=1000a/Lb) between +10 and +20. We conclude that the ethylene degreening treatment, which did not have any effect on the internal quality that consumers perceive, is a potent postharvest tool to increase citrus fruit sales at the beginning of the season.

Citrus rootstocks are a relevant tree part that contributes to crops adapting to biotic and abiotic conditions, it becoming a key factor to face the current era of climate change.Although the emphasis of most studies on rootstocks has been placed on the yield and optimization of the citrus fruit grown in different environments, other studies have paid attention to the effect of rootstock on fruit quality. Hence the quality of citrus fruit is becoming increasingly more relevant as consumers demand high internal and external qualities to eat citrus fruit fresh. To better understand how rootstock influences citrus fruit quality, the literature that focuses on physico-chemical parameters, nutritional compounds and physiological disorders has been revised. This review points out the influence that the external aspects surrounding plants has on fruit quality, such as the rootstock/scion interaction, the water uptake capacity of roots, the modification of the photosynthetic rate or availability of nutrients minerals.

A comparative study of the primary and secondary metabolites of the juice of several mandarin cultivars with different pollination, seed production and parthenocarpic abilities was carried out, and the antioxidant capacity of the hydrophilic fraction was measured. Correlation by a Principal Component Analysis and a Cluster Analysis was used. By a multivariate analysis, the 15 citrus cultivars were clustered into four groups consistently with citrus types. The presented data are an important factor for choosing varieties with high potential as a nutraceutical source. These aspects are necessary as consumers demand prevention of health problems through nutrition and certain fruit quality traits, including fruit size, internal quality, good rind color and easy peeling.

The aim of this study was to establish DRIS (Diagnosis and Recommendation Integrated System) norms and Nutritional Optimal Ranges (NOR) for ‘Rojo Brillante’ Protected Designation of Origin (PDO) ‘Ribera del Xúquer’. The database contained 800 leaf samples collected in different crop phenological stages [after flowering (AF), fruit enlargement (FE), fruit colouring (FC), and harvesting HV)]. DRIS norms (78) were established for macronutrients: N, P, K, Ca, Mg and S; micronutrients B, Cu, Fe, Mn, and Zn and salinity elements: Na and Cl. The Nutrient Balance Index (NBI; the absolute value of the sum of the DRIS indices) was used to determine the optimal sampling period. Fruit enlargement was the period during which persimmon trees were more nutritionally balanced regardless of sprout origin (vegetative or floral) and irrigation type (drip or flood) in orchards