Strawberries produced in the semi-arid region of Minas Gerais, Brazil: quality of the frozen fruit and pulp

Abstract The freezing of whole strawberries or pulp can provide raw material for the out of season use of strawberries in yogurts, fillings, toppings, ice cream and juices. However, although the consumption is not in natura, the quality of the final product should be satisfactory. This study aimed to evaluate the quality of strawberries produced in the semi-arid region of Minas Gerais, Brazil, frozen either whole or in the form of pulp, during storage. Fruits of the cultivars Tudla, Oso Grande, Albion and Portola were produced in the semi-arid region of Minas Gerais, and after harvesting, were washed, vacuum packed (whole or pulp) and frozen for up to 180 days. The treatments consisted of cultivars (c) and days of storage (d), constituting a double factorial c × d design, using three repetitions of 10 fruits per batch or three pulp-packs, respectively, for the frozen whole fruit assessments. The intensity of the red colour of the whole strawberries or strawberry pulp reduced during storage (reduction of hue). When whole, the cultivars 'Tudla', 'Oso Grande' and 'Portola’ were a lighter red than' Albion ', but in the form of pulp, there was no difference between 'Tudla' and 'Albion'. The 'Oso Grande' strawberries, stored whole or in pulp, showed higher soluble solids contents than those of the other cultivars, and 'Portola' showed the lowest content and also the lowest titratable acidity (when whole). The fruits and pulp of the ‘Tudla’ cultivar were more acidic. During the storage of frozen whole or pulped strawberries produced in the semi-arid region of Minas Gerais, changes occurred in the colour, soluble solids and titratable acidity.

摘要 整颗草莓或草莓果泥经冷冻处理后，可作为非应季草莓原料应用于酸奶、馅料、顶料、冰淇淋及果汁的生产。但即便产品不直接鲜食，其最终品质仍需符合要求。本研究旨在评估巴西米纳斯吉拉斯州半干旱地区种植的草莓，分别以整果或果泥形式冷冻后，在贮藏期间的品质变化。供试栽培品种为Tudla、Oso Grande、Albion及Portola，均在米纳斯吉拉斯州半干旱地区种植。采收后，样品经清洗、真空包装（整果或果泥形态），并进行最长180天的冷冻贮藏。试验设置栽培品种（c）与贮藏天数（d）两个因素，采用双因子c×d试验设计；整果冷冻品质评价组每批次设置3次重复，每次重复包含10颗草莓，果泥组则对应3份果泥包装。贮藏期间，整颗草莓或草莓果泥的红色色泽强度均出现下降，色相（hue）降低。整果形态下，‘Tudla’、‘Oso Grande’与‘Portola’的红色色泽较‘Albion’更浅；但在果泥形态下，‘Tudla’与‘Albion’之间无显著色泽差异。‘Oso Grande’品种无论以整果还是果泥形式贮藏，其可溶性固形物（soluble solids）含量均高于其余品种；‘Portola’的可溶性固形物含量最低，且整果形态下的可滴定酸度（titratable acidity）亦为最低。‘Tudla’品种的果实及果泥酸度最高。综上，在巴西米纳斯吉拉斯州半干旱地区生产的冷冻整果或果泥草莓，其贮藏过程中色泽、可溶性固形物及可滴定酸度均发生显著变化。