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Cardoso Freitas Lopes de Freitas, Ana Cristina
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- Incorporation and survival of probiotic bacteria in whey cheese matricesPublication . Madureira, Ana R.; Gião, Maria S.; Pintado, Manuela E.; Gomes, Ana M. P.; Freitas, A. Cristina; Malcata, F. XavierThe viabilities of probiotic strains of Lactobacillus acidophilus, Lactobacillus paracasei, Bifidobacterium animalis, and Lactobacillus brevis were studied following incorporation in a whey cheese matrix. Experimental production of plain, as well as sugar-added or salt-added whey cheeses, was based on the traditional manufacture protocol of Requeijäo, a Portuguese whey cheese that essentially results from protein denaturation via heating of whey at about 85°C. After inoculation, the experimental whey cheeses were incubated at 7°C for 28 d. Our results have shown that all strains considered were able to maintain (or even increase) their initial viable numbers; L. paracasei ssp. paracasei strain LCS-1 and L. acidophilus strain Ki exhibited the highest cell viability in plain Requeijão by the end of the storage period—an increase of ca. 2 log cycles in their viable numbers was actually recorded. Among the parameters studied, bacterial species and matrix nature had the most important effect upon viable counts, whereas time of storage was the least important.
- Sweet whey cheese matrices inoculated with the probiotic strain Lactobacillus paracasei LAFTI® L26Publication . Madureira, Ana Raquel; Soares, José Carvalho; Pintado, M. E.; Gomes, Ana M. P.; Freitas, A. C.; Malcata, F. XavierConsumption of dairy products containing viable probiotic strains has increased dramatically in recent years, owing to general health claims associated therewith. This trend has boosted diversification of the portfolio of said products, including whey cheese matrices. However, taking into account the relatively poor organoleptic and textural features of these matrices, improvement is in order via incorporation of selected additives, provided that viability of the strains is duly assayed. Lactobacillus paracasei LAFTI® L26 was accordingly incorporated into whey protein solid matrices, in the presence of several additives aimed at enhancing their organoleptic appeal and textural performance. These matrices were produced from a combination of either ovine or bovine whey (or a mixture thereof) with ovine milk, and were inoculated at 10% (v/v) with the probiotic strain. Sugar, sugar and aloe vera, sugar and chocolate, and sugar and jam were further added, and the resulting products were then stored at 7 ◦C for 21 d. In general, viable cell numbers remained high in all experimental matrices throughout storage. Despite the observed low extents of breakdown, proteolytic activities by the end of storage were higher in matrices containing jam. Furthermore, L. paracasei partially converted lactose into lactic acid in these matrices. Additives enhanced the organoleptic features of whey cheeses, and produced different textural patterns. The higher sensory scores were attained by matrices containing sugar: sugar and aloe vera received the best scores by 3 d of storage, but these scores decreased as storage time elapsed.
- Review: Technological and organoleptic issues pertaining to cheeses with denomination of origin manufactured in the Iberian Peninsula from ovine and caprine milksPublication . Freitas, A.C; Macedo, A. C.; Malcata, F. X.A few European countries have created Appélations d'Origine Protegée (AOP) in order to support legal protection and hence promote enforcement of high-quality standards of selected food products. This paper comprehensively reviews and updates fundamental and applied aspects encompassing tech nological and organoleptic characteristics of AOP traditional cheeses manufactured in the Iberian Peninsula, from ovine and/or caprine milks. Those cheeses from Portugal and Spain can be divided into four distinctive groups, based on milk source and rennet type: (i) Azeitão, Castelo Branco, Évora, Nisa, Serpa, Serra da Estrela and La Serena cheeses, manufactured with raw ovine milk and coagulated via plant rennet; (ii) Terrincho, Idiazábal, Manchego, Roncal and Zamorano cheeses, elaborated with raw ovine milk and coagulated via animal rennet; (iii) Cabra Transmontano and Majorero cheeses, manufac tured with raw caprine milk and coagulated via animal rennet; and (iv) Amarelo da Beira Baixa, Picante da Beira Baixa and Rabaçal cheeses, manufactured with mixtures of raw ovine and caprine milks and coagulated via animal rennet. Considerable differences between Portuguese and Spanish AOP cheeses exist; the former are, in general, characterized by softer consistencies and similarities to one another in terms of manufacturing protocols (usually encompassing coagulation of plain raw milk followed by slow draining of the curd), whereas the latter are, in general, larger and firmer.
- Produção por tecnologias optimizadas de lacticínios tradicionais certificados: PROLACTISPublication . Reis, Patrícia M.; Domingos, Tiago D.; Freitas, A. Cristina; Macedo, Ângela C.; Trigueiros, José J. B. L.; Malcata, F. Xavier