Percorrer por autor "Azevedo, Miguel"
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- Antifungal capacity of commercial flavouring agents against spoilage yeastsPublication . Silva, Beatriz Nunes; Carvalho, Teresa Bento de; Azevedo, Miguel; Silva, Beatriz; Teixeira, PaulaIntroduction: Yeasts are involved in the spoilage of foods and beverages, causing undesirable changes in the physicochemical and sensory properties of the products. Prevention of food spoilage requires good manufacturing and hygiene practices, but additives are also frequently used to hinder yeast growth. Nowadays, consumers and companies are moving from chemical additives towards other options that can be perceived as more natural and less harmful to human health: biopreservatives. Objectives: Assess the antifungal capacity of three commercial flavouring agents against: four Zygosaccharomyces yeasts isolated from pastry fillings (Z. bailii, Z. parabailii, Z. bisporus and Z. rouxii); two yeasts isolated from thermo-sealed packaging (Rhodotorula mucilaginosa and an unidentified yeast). Conclusions: While the commercial extracts did not exhibit antifungal activity against all the tested yeasts, the results are still encouraging in several cases. These natural alternatives may be useful to replace the chemical preservatives currently used in the pastry industry (such as potassium sorbate), as they may hamper yeast growth during the manufacturing process.
- Clean label antimicrobial strategies for fungal spoilage of pastry fillingsPublication . Carvalho, Teresa Bento de; Silva, Beatriz Nunes; Azevedo, Miguel; Silva, Beatriz; Teixeira, PaulaIntroduction: Fungal spoilage is a key concern for the food industry, leading to hefty economic losses Consequently, the food waste that follows is also a grave matter not only due to its social or humanitarian aspect but also its environmental impact. Objectives: The aim of this study was to assess the antifungal activity of commercial clean label alternatives to potassium sorbate against moulds isolated from a pastry filling. Methodology: Isolation of fungi from a contaminated product used in antimicrobial activity tests of clean label preservatives. Results and discussion: Fungal growth was not completely inhibited at the concentrations recommended by the manufacturers. The antimicrobial agents are still effective and, therefore, a promising alternative to traditional chemical preservatives for the pastry industry. Conclusions: In this context, the clean label movement is trending to offer natural spoilage control strategies while having their organoleptic characteristics and, most importantly, safety in sight. Future research into the application of these antimicrobial compounds in pastry fillings is an important step to guarantee their efficacy and application in the industry.
- Enhancing carob flour (Ceratonia siliqua L.) for by-product utilization in food industries: carob syrup production, functional profiling and applicationPublication . Vilas-Boas, Ana Martins; Brassesco, María Emília; Quintino, Andreia C.; Medronho, Bruno; Vieira, Margarida C.; Brandão, Teresa R. S.; Silva, Cristina L. M.; Silva, Beatriz; Azevedo, Miguel; Pintado, ManuelaThe focus on by-product valorization in the food industry, particularly from the carob pod, underscores a commitment to sustainability and resource efficiency. This fruit, sourced from the leguminous evergreen carob tree (Ceratonia siliqua L.), is renowned for its adaptable flavour and nutritional value, in Mediterranean regions such as Portugal. Its production yields significant by-products, presenting environmental challenges when not managed efficiently. Innovative approaches, including integral carob flour production, aim to optimize utilization while minimizing waste and energy consumption. This study repurposed carob waste to produce novel, value-added ingredients like carob syrup, by thermal hydrolysis of integral carob flour using water at 1:3 solid-to-liquid ratio - obtaining up to 50 % solubility yield. The resulting syrup exhibited 72 % °Brix, a melting temperature (Tm) of approximately 130 °C and predominantly viscous behavior with minimal elastic (solid-like) response. Lastly, the syrup was incorporated into a carob-based brigadeiro, replacing conventional glucose-fructose syrup. Simulated gastrointestinal digestion revealed enhanced bioaccessibility of sugars and phenolics, and increased antioxidant activity during the intestinal phase. Despite sugar availability, the prebiotic activity of the syrup decreased when embedded in the brigadeiro matrix, potentially due to interactions with polyphenols or organic acids. Cytotoxicity and permeability assays confirmed safety at ?0.5 % (w/v) and supported intestinal barrier integrity. These findings support the use of integral carob flour for producing multifunctional ingredients, contributing to circular economy models while meeting consumer demands for healthier, sustainable food products.
- From ingredient characterization to clinical evaluation: developing protein- and fiber-enriched food products for a 65+ population (Diet65+ Project)Publication . Salsinha, Ana Sofia; Silva, Isa; Correia, Marta; Oliveira, Isabel; Azevedo, Miguel; Pintado, Manuela
- Modification of carob powder (Ceratonia siliqua L.) for by-product valorisation in the food industriesPublication . Vilas-Boas, Ana M.; Brassesco, María Emilia; Brandão, Teresa R. S.; Azevedo, Miguel; Silva, Cristina L. M.; Pintado, Manuela E.Carob fruit originates from the carob tree, is a leguminous evergreen tree (Ceratonia siliqua L.) cultivated in the Mediterranean area, namely in Portugal [1]. Its production is highly relevant, extensive, and sustainable. Carob pods contain various relevant nutrients, which include proteins, carbohydrates, and fibers [2]. In this study, after applying an innovative milling process to obtain an integral carob flour [3], carob powder with granulometry >100 µm, which is composed principally of insoluble fiber, was modified by a two-step acidic/thermal and enzymatic hydrolysis to improve its functional properties as a result of the cleavage and degradation of cellulose, hemicellulose, and lignin compounds [4],[5]. The optimal time and solvent concentration were considered as experimental factors for the acidic/thermal hydrolysis, as well as the ratio of enzyme-substrate for the enzymatic hydrolysis. The selected response variable was the solubility. The assessed solvents were sulfuric, lactic, and acetic acids, deionized water at 100 °C, and the enzymes were cellulase and xylanase. Furthermore, it was assessed how the industrial steps at industrial level could be minimized in order to decrease process’s costs and runtime.The acidic/thermal hydrolysis results show that the lower solvent concentration and the higher hydrolysis time were optimal conditions for increasing the solubility. However, using an acidic solvent did not differ significantly from using deionized water, a greener and more environmentally solvent for industrial scales. As for the enzymatic hydrolysis, results suggest that when applied as an individual step, it could improve the solubility by 30%, but when applied uninterruptedly after the thermal hydrolysis, no significant improvement in solubility was detected. In conclusion, the optimal modification process for carob powder encompasses a single thermal hydrolysis using water to obtain 50% solubility of the initial carob powder. The resulting liquid by-product can be used to produce sweeteners, fillings, creams, etc., highlighting the importance of food-chain valorization in food industries.
- Modification of carob powder (Ceratonia siliqua L.) for by-product valorisation in the food industriesPublication . Vilas-Boas, Ana M.; Brassesco, María Emilia; Brandão, Teresa R. S.; Azevedo, Miguel; Silva, Cristina L. M.; Pintado, Manuela
- Natural preservation strategies for fruit: based bakery fillingsPublication . Teixeira, Paula; Tomé, Elisabetta; Carvalho, Maria Teresa Bento de; Sousa, Pedro; Oliveira, Isabel; Azevedo, MiguelThe storage stability of an industrial banana-based filling commonly used in bakery applications was evaluated over 70 days at 22 °C and 62% relative humidity. Potassium sorbate (0.095%) was replaced with a commercial red fruit extract (0.5%) as a natural preservative. Microbiological characteristics, including total viable counts, molds and yeasts and spore-forming bacilli, were assessed throughout storage. Additionally, physicochemical and rheological properties were evaluated. The results suggest that the commercial red fruit extract is a promising “clean label” alternative to potassium sorbate, effectively maintaining the desired quality and safety of the banana-based filling during storage.
- Particle size effect of integral carob flour on bioaccessibility of bioactive compounds during simulated gastrointestinal digestionPublication . Vilas-Boas, Ana M.; Brassesco, María E.; Quintino, Andreia C.; Vieira, Margarida C.; Brandão, Teresa R. S.; Silva, Cristina L. M.; Azevedo, Miguel; Pintado, ManuelaCarob fruit is native to the Mediterranean region and produced mainly in Portugal, Italy, Morocco and Turkey. The production of the carob fruit in Portugal is highly extensive and sustainable. Currently, carob flour (CF) production is mainly achieved after pulp separation, despite it having been demonstrated that the seeds improve the extraction efficiency of bioactive compounds such as polyphenols, promoting human health. This study aimed to produce an integral CF through an innovative process and assess its physicochemical and bioactive properties at different particle sizes throughout simulated gastrointestinal tract (GIT) digestion. The sugar content profile obtained throughout GIT digestion indicated that sucrose, the sugar present at the highest concentration in undigested CF, was digested and broken down into simple sugars, namely glucose and fructose. The total phenolic content (TPC) and antioxidant activity obtained for the ≤100 µm fraction were in accordance and gastric digestion promoted an increase in the TPC value compared to the undigested sample. The >100 µm fractions displayed a distinct profile from the ≤100 µm fraction. This study showed that the particle size affects the sugar, antioxidant and total phenolic content of CFs and also their gastrointestinal tract digestion. The ≤100 µm fraction demonstrated the most suitable profile as a functional food ingredient.
- Sensory evaluation, acceptability, and consumer insights of protein- and fiber-enriched foods tailored for older adults: the diet65+ projectPublication . Salsinha, Ana Sofia; Ferreira, Miguel Magalhães; Correia, Marta; Oliveira, Isabel; Azevedo, Miguel; Pintado, Manuela; Oliveira-Silva, Patrícia
- Substituição de sorbato de potássio por conservantes naturais em recheio de banana: avaliação da estabilidade durante o armazenamentoPublication . Carvalho, Teresa Bento de; Silva, Beatriz Nunes; Silva, Beatriz; Oliveira, Isabel; Azevedo, Miguel; Tomé, Elisabetta; Teixeira, PaulaIntrodução :Os conservantes de síntese química, como o sorbato de potássio, têm sido utilizados pela indústria alimentar para prevenir a deterioração microbiana. Contudo, a crescente exigência dos consumidores por alimentos 'naturais' e 'sem químicos', bem como as preocupações ambientais, têm levado tanto os consumidores como a indústria a procurar conservantes naturais alternativos, denominados 'clean label', para substituir os aditivos químicos convencionais. Objectivos: O presente estudo teve como objetivo avaliar a estabilidade durante o armazenamento (22 ℃ e 62% de humidade relativa) de um recheio de banana produzido a nível industrial, comercializado para utilização em produtos de pastelaria e panificação. O sorbato de potássio comumente utilizado foi substituído por conservantes "clean label" existentes no mercado, à base de extratos vegetais.