Browsing by Author "Marques, Filipe M."
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- Determination of shelf life of table olive flours produced from Cobrançosa cultivarPublication . Ramalhosa, Elsa; Marques, Filipe M.; Pereira, J.A.; Rodrigues, NunoIn the present work, flours from table olives from the cultivar Cobrançosa subjected to natural fermentation were prepared. These flours will be added to several dishes or sauces, such as mayonnaises. Only the pulp of the table olives was used to produce the fours. The product's shelf life was determined when subjected to storage (with and without exposure to light) at room temperature. Several parameters were evaluated, such as colour; water activity; moisture, ash and fat contents; total phenols (TP); antioxidant activity percentage of DPPH radical scavenging activity; oxidative stability - peroxide value (PV) and ultraviolet spectrophotometry analysis (extinction coefficients (K) at 232 and 268 nm); and sensory analysis, over 0, 1, 2 and 3 months. For each condition, three independent samples were always analysed. Water activity varied between 0.110 and 0.369, having increased over time. The moisture content rose from the beginning to one month. The TP varied between 221 and 1015 mg gallic acid/kg of oil, with no defined trend. No significant differences were detected among the samples for the percentage of DPPH radical scavenging activity and PV. However, this parameter increased over time, indicating the occurrence of oxidation. No significant changes on K232 and K268 values were observed over time and among samples. Regarding the sensory analysis, until one month, the samples presented a reasonable overall assessment, while after one and two months, the samples had an intense rancid smell. Thus, it was concluded that the storage time had a more significant effect than light on the quality of the flours and the shelf life was about one month.
- Determination of shelf life of table olive flours produced from Cobrançosa cultivarPublication . Ramalhosa, Elsa; Marques, Filipe M.; Pereira, J.A.; Rodrigues, NunoIn the present work, flours from table olives from the cultivar Cobrançosa subjected to natural fermentation were prepared. These flours will be added to several dishes or sauces, such as mayonnaises. Only the pulp of the table olives was used to produce the fours. The product's shelf life was determined when subjected to storage (with and without exposure to light) at room temperature. Several parameters were evaluated, such as colour; water activity; moisture, ash and fat contents; total phenols (TP); antioxidant activity percentage of DPPH radical scavenging activity; oxidative stability - peroxide value (PV) and ultraviolet spectrophotometry analysis (extinction coefficients (K) at 232 and 268 nm); and sensory analysis, over 0, 1, 2 and 3 months. For each condition, three independent samples were always analysed. Water activity varied between 0.110 and 0.369, having increased over time. The moisture content rose from the beginning to one month. The TP varied between 221 and 1015 mg gallic acid/kg of oil, with no defined trend. No significant differences were detected among the samples for the percentage of DPPH radical scavenging activity and PV. However, this parameter increased over time, indicating the occurrence of oxidation. No significant changes on K232 and K268 values were observed over time and among samples. Regarding the sensory analysis, until one month, the samples presented a reasonable overall assessment, while after one and two months, the samples had an intense rancid smell. Thus, it was concluded that the storage time had a more significant effect than light on the quality of the flours and the shelf life was about one month.
- Dose-response effects of copper, potassium silicate, potassium fosfonate, metalaxil-m and fosetil-al on Phytophthora Mycelial growth in vitro and on chestnut seedlings under greenhouse conditionsPublication . Marques, Filipe M.; Coelho, Valentim; Moura, Luísa; Gouveia, Maria EugéniaEuropean Chestnut (Castanea sativa) is one of several tree species that is affected by Phytophthora root rot. Disease syndrome include root rot that is evidenced above soil by yellow discoloration of leaves, die-back and continuous and severe tree decline. Apoplectic symptoms also occur and tree suddenly collapse during hot weather conditions of summer. Phytophthora root rotting of fruit trees are frequently treated with fungicides which inhibits the growth of pathogens. For chestnut, in Portugal, there is currently no authorized chemical substances for direct control of soilborne Phytophthora species. However, strictly avoidance of disease spread is a basic requisite for disease management of initially localized spots of infected trees which can be largely improved by direct applications of efficient active substances. In this work we focused on the study of direct effects of copper, potassium silicate, potassium fosfonate, metalaxil-M and fosetyl-Al on Phytophthora mycelial growth to improve IDC therapeutic of localized treatment. Crop management still remains the most efficient measure to maintain tree vigor during the long-life span of chestnut trees and conservation tillage methods to reduce inoculum potential and waterborne inoculum spread. A collective management approach integrating all sanitary measure will be necessary to control IDC in chestnut ecosystem.