No abstract

This study evaluated the effect of pasteurization followed by storage under different conditions on the sensory attributes of frozen juçara pulp using quantitative descriptive analysis (QDA). Pasteurization of packed frozen pulp was performed by its immersion in stainless steel tank containing water (80°C) for 5 min, followed by storage under refrigerated and frozen conditions. A trained sensory panel evaluated the samples (6°C) on day 1, 15, 30, 45, 60, 75, and 90. Sensory attributes were separated as follows: appearance (foamy, heterogeneous, purple, brown, oily, and creamy), aroma (sweet and fermented), taste (astringent, bitter, and sweet), and texture (oily and consistent), and compared to a reference material. In general, unpasteurized frozen pulp showed the highest score for foamy appearance, and pasteurized samples showed highest scores to creamy appearance. Pasteurized samples remained stable regarding brown color development while unpasteurized counterparts presented increase. Color is an important attribute related to the product identity. All attributes related to taste and texture remained constant during storage for all samples. Pasteurization followed by storage under frozen conditions has shown to be the best conservation method as samples submitted to such process received the best sensory evaluation, described as foamy, slightly heterogeneous, slightly bitter, and slightly astringent.

Devido ao processo de expansão das fronteiras agrícolas, principalmente de monoculturas, o bioma Mata Atlântica vem perdendo espécies constantemente. A uvaieira (Eugenia pyriformis Cambess) é uma árvore frutífera nativa, possui frutos carnosos e aveludados sendo muito apreciada na forma de sucos, geléias e doces em geral; logo, a ciência e a tecnologia dos alimentos se tornam uma ferramenta fundamental para estudar a potencialidade dos alimentos oriundos deste bioma e assim contribuir com a preservação dessas espécies. Este trabalho objetivou caracterizar o fruto in natura e a polpa de uvaia congelada através da determinação do seu teor de ácido ascórbico e carotenoides, bem como da qualidade da sua polpa congelada através de avaliações físico-químicas. Os resultados indicaram que o fruto in natura e sua polpa congelada possuem elevados teores de ácido ascórbico (100,73 mg 100 g -1 e 84,74 mg 100 g -1 respectivamente), carotenoides (0,91 µg carotenóides totais g -1 e 0,366 µg carotenóides totais g -1 respectivamente) e compostos fenólicos (4,89 mg ác. gálico 100 ml -1 e 6,07 mg ác. gálico 100 ml -1 respectivamente), podendo ser empregada para a dieta alimentar.

Dedico este trabalho aos meus filhos, Davi e Pedro, que estiveram comigo do ventre ao nascimento durante o mestrado. Dedico também ao meu esposo, Luís, pela paz, companheirismo e sabedoria de todos os dias.

Camu-camu (Myrciaria dubia), a fruit native to the Brazilian Amazon, is considered a source of antioxidant compounds. Due to its high perishability, postharvest studies aimed at increasing its shelf life are required. The aim of this study was to evaluate the influence of harvesting time on the conservation of the physicochemical characteristics and antioxidant compounds of camu-camu during cold storage. The fruits, harvested at different ripening stages (red and reddish-green peel), were stored in polyethylene terephthalate trays at 15 °C and 90% relative humidity. The following analyses were carried out on days 1, 2, 5, 7, 9 and 13 after harvest: luminosity, hue angle and chromaticity, pH, soluble solids content, titratable acidity, SS/TA, ascorbic acid content, total phenolic content, total anthocyanin content and free-radical-scavenging activity by the 1,1-diphenyl-2-picryl-hydrazil method. The data were submitted to a multivariate analysis. The fruits harvested at different ripening stages showed different postharvest characteristics, highlighting the parameters of colour, flavour and antioxidants. The reddish-green fruits, despite their low concentration of anthocyanins during storage, showed high levels of phenolic compounds, ascorbic acid and antioxidant activity, which were maintained for nine days of cold storage. Due to the flavour characteristics and antioxidant compounds, it is recommended that camu-camu be harvested in the reddish-green maturation stage to extend its shelf life.

Camu-camu (Myrciaria dubia) is a wild Amazon native fruit, with great nutritional potential due to high ascorbic acid content. As transport reduces its shelf life and fresh consumption is limited because of high acidity, posing obstacles to commercialization, pulping and pasteurization can enhance its shelf life. This study aimed to verify camu-camu pulp stability after postpackage pasteurization, using laminated packaging, assessing physical and chemical alterations caused by refrigerated (5 °C), frozen (-18 °C), and room temperature (28 °C) storage for 45 days. Samples were pasteurized in tanks at 75 °C for 1 min and rapidly cooled to room temperature. Frozen pulp presented the best physical and chemical characteristics at the end of 45 days storage (about anthocyanins: 0.8 mg equivalent to cianidine 3-glucoside 100 g-1 pulp; 2.2 g ascorbic acid 100 g-1 pulp and 7% of phenolic compounds), but refrigerated stored samples also showed promising results at 45 days, maintaining the initial characteristics throughout the study. Even the pulps at roomtemperature storage are cheaper option to preserve the product, they were degraded at 30 days of storage.