Browsing by Author "Amaro, Ana"
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- Antioxidant and anti-browning activity of different bioactive compoundsPublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo; Rocha, Sílvia M.; Silvestre, Armando; Isidoro, Nelson; Pintado, Manuela
- Antioxidant and anti-browning activity of different bioactive compoundsPublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo; Rocha, Sílvia M.; Silvestre, Armando; Isidoro, Nelson; Pintado, Manuela
- Antioxidant extracts from natural sources as potential enzymatic browning inhibitors in fruitsPublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo C.; Rocha, Sílvia M.; Silvestre, Armando J. D.; Isidoro, Nélson; Pintado, Manuela
- Cereal bars functionalized through Bifidobacterium animalis subsp. lactis BB-12 and inulin incorporated in edible coatings of whey protein isolate or alginatePublication . Pereira, Joana Odila; Soares, José; Monteiro, Maria J. P.; Amaro, Ana; Gomes, Ana; Pintado, ManuelaCurrently, cereal bars are gaining interest globally because of their nutritionally balanced and convenient nature. One healthy strategy is to add probiotics to cereal bars, to make them a functional food product. So, in this study a cereal bar functionalized with edible coatings of whey protein isolate (WPI) and alginate (ALG) incorporated with Bifidobacterium animalis subsp. lactis BB-12 and inulin was developed and evaluated for its consumer acceptability and physicochemical and microbiological properties, throughout 90 days of storage. WPI-coated cereal bars were shown to be the solution that better maintained the level of the incorporated probiotic strain when compared to the ones coated with ALG, throughout storage and throughout in vitro gastrointestinal digestion. The physicochemical properties of the bars, namely aw, moisture content, color and texture, were not altered during the storage period. The sensory evaluation showed that coated bars were accepted as well as control bars. Moreover, the consumers appreciated better the odor and flavor of WPI-coated bars than those of ALG-coated bars.
- Effect of processing and storage on nutritional and functional quality of strawberryPublication . Pereira, Maria João Valle; Amaro, Ana; Carvalho, Susana; Vasconcelos, Marta; Pintado, M. E.
- Evaluation of natural extracts as potential enzymatic browning inhibitorsPublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo; Rocha, Sílvia M.; Silvestre, Armando; Isidoro, Nelsón; Pintado, Manuela
- Evaluation of natural extracts as potential enzymatic browning inhibitorsPublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo; Rocha, Sílvia; Silvestre, Armando; Isidoro, Nélson; Pintado, ManuelaEnzymatic browning in fruits represents a difficult problem for Food Industry, especially with recent restrictions in the use of synthetic antioxidants. It is often associated with undesirable off-flavors and negative effects on taste and nutritional value. This physiological disorder is mainly due to the oxidation of natural phenolic compounds into quinones that are polymerized to brown pigments by polyphenol oxidase (PPO). Peroxidase (POX) is also alleged to be related to browning development, by inducing H2O2 oxidation of phenolic compounds. Prevention of browning reactions, catalyzed by these enzymes, has traditionally been accomplished by various chemicals, as ascorbic and citric acids. Partial control of this disorder can be obtained with the application of antioxidants, which compete with common substracts for the enzymatic activity. This study assessed the potential of natural extracts, with antioxidant properties (such as soy protein concentrate, extracts of apple byproduct and olive leaves) as novel enzymatic browning inhibitors. The antioxidant capacity was assessed by the radical scavenging assay using ABTS+ radical. The natural extracts inhibitory effect on PPO and POX activity was evaluated using a spectrophotometric assay by reaction of the natural extracts with the pure enzymes, using catechol and guaiacol as substrates, respectively. The present study demonstrated that olive leaves had the highest antioxidant capacity (2.688 ± 0.006 mg/mL TEAC equivalent), however, apple byproduct was the most effective on PPO and POX activity inhibition. The study has practical implications in generating novel natural extracts with potential application as anti-browning agents.
- Nutritional and functional audit to the process of fresh-cut strawberryPublication . Amaro, Ana; Pereira, Maria João; Carvalho, Susana; Vasconcelos, Marta; Pintado, M. E.
- ReStoragePear: development of strategies to the prevention of superficial scald and internal browning in the Rocha pear and quality assurance in long-term storagePublication . Dias, Cindy; Amaro, Ana; Salvador, Ângelo; Rocha, Sílvia M.; Silvestre, Armando; Isidoro, Nélson; Pintado, Manuela
- ß-Farnesene exogenous application as a novel damage induction model to fast explore the effectiveness of postharvest strategies: the case study of the ‘Rocha’ pear DOPPublication . Dias, Cindy; Amaro, Ana; Fonseca, Alexandre; Ferrante, António; Silvestre, Armando; Rocha, Sílvia M.; Isidoro, Nélson; Pintado, ManuelaSince the prohibition of diphenylamine, replacement strategies have been needed for long-term disorder prevention, namely superficial scald (SC), in fruit. However, as this disorder only appears after months under cold storage, the assessment of effective strategies to prevent this disorder requires long periods. To tackle this challenge, we report in this paper a rapid and reliable system to induce symptoms, such as SC, based on storage under a β-farnesene-enriched atmosphere. Using this model, SC symptoms in ‘Rocha’ pear were induced after 15 d at 20◦ C. As proof of concept, this model system allowed the study of the efficiency of antioxidant natural-based coatings on ‘Rocha’ pear quality maintenance. Pears treated with the coatings were submitted to 4 months of commercial storage under normal atmosphere conditions and the results were compared with those obtained using the induction model system. A PCA of chemical data allowed us to conclude that the model developed simulates the potential of certain strategies to prevent disorders.