Quality characterization of Andean blackberry fruits (Rubus glaucus Benth.) in different maturity stages in Antioquia

Abstract

<p>Product quality and safety are two essential characteristics for the fruit market, making it necessary to normalize and standardize processes in order to improve their commercialization. In this study, the quality of two Andean blackberry cultivars grown in two regions of Antioquia (Envigado and Guarne), Colombia, from different maturity stages as defined by the Norma Tecnica Colombiana 7146 (NTC Spanish) was characterized. The parameters that were found suitable for the fruit quality characterization were: weight, total solid soluble content (TSS), titratable acidity (TA), maturity index (MI), color index (CI) and firmness (F). The equatorial diameter (ED) maintained its importance relative to the standard and the market, along with the juice yield (JY). The quotient a*/b* presented the best correlation with the visual color scale as defined in the standard. The TSS ranges defined in NTC 4106 were not verified in this studied for fruits grown in the agro-climatic conditions of Antioquia. Linear regression models are a useful tool for making quick and easy comparisons and estimations of the quality parameters. As a general recommendation, we propose the following minimal requirements for harvesting Andean blackberries in the Antioquia region of Colombia for the domestic fresh market: <span style="text-decoration: underline;">&gt;</span> class I, CI <span style="text-decoration: underline;">&gt;</span> 3, MI (citric acid) ≥ 2.5, JY ≥ 35%, size (diameter and/or weight) established by the market or NTC; for the export market: class supreme, 2 <span style="text-decoration: underline;">&lt;</span> CI &lt; 3, MI (citric acid) ≥ 1.5, JY ≥ 35%, F <span style="text-decoration: underline;">&gt;</span> 0,6 N, size (weight and/or diameter) established by the importer; and for the processing industry: class II, CI <span style="text-decoration: underline;">&gt;</span> 3, ºBrix <span style="text-decoration: underline;">&gt;</span> 6, JY <span style="text-decoration: underline;">&gt;</span> 40%.</p>