Study of Textural, Chemical, Color and Sensory Properties of Organic Blueberries Harvested in Two Distinct Years: A Chemometric Approach

In Portugal, two groups of blueberry plants are of interest: the Northern and the Southern Highbush Blueberry. The short season and short shelf life of blueberries yields excess fruit, and those harvests not destined for the fresh market are frozen or processed, sometimes leading to economic losses for the producers. From a technological point of view, fruit characterization is performed on the basis of physical, chemical properties as well as organoleptic properties (texture, flavor, color/pigmentation). These properties are directly correlated with fruit utilization. Thus, in this work, chemometric tools, such as texture, soluble solids (SS), titratable acidity (TA), fruit surface color and a trained sensory panel, for the exploration of textural, chemical, color and sensory characteristics of four blueberry cultivars harvested in two different years were applied. Surface color, maximum force, SS, TA and SS/TA ratio varied among cultivars and years and, in general, all the fruits presented in 2013 had lower values for SS and TA when compared with those collected in 2011. After analyzing all the parameters and independently of their origin, Duke and Palmetto seem to be more suitable for fresh market consumption since the attribute crispness did not change significantly between the 2 years, while Camellia, a cultivar where the attribute crispness, seems to be weather dependent, and Legacy a cultivar with less odor and flavor, seems to be more suitable for processing into products such juice and jam. Practical ApplicationsBlueberry is a product of interest due to their nutritional and health benefits. Recently, scientists have determined that is the blueberry-like flavor intensity the eating quality that has a much higher correlation to consumer acceptance than the traditional measures of sweetness, acidity or sugar/acid. Ripeness and maturity are the key factors that influence the taste of a fruit. Ripening processes play a key role in flavor development and can affect the chemical and sensory characteristics (acidity, sweetness) of fruits. Thus, with this study we can understand the influence of the harvest year in the textural and sensory attributes of blueberry fruits that can help to determine the optimal use of fruit.