138 research outputs found

    Stability of free and immobilized Lactobacillus acidophilus and Bifidobacterium lactis in acidified milk and of immobilized B-lactis in yoghurt

    Get PDF
    This study evaluated the stability of Bifidobacterium lactis (Bb-12) and of Lactobacillus acidophilus (La05) both free and immobilized in calcium alginate, in milk and in acidified milk (pH 5.0,4.4 and 3.8). The stability of immobilized B. lactis in yoghurt (fermented to pH 4.2), during 28 days of refrigerated storage was also evaluated. The efficiency Of two Culture media (modified MRS agar and Reinforced Clostridial Agar plus Prussian Blue) for counting of B. lactis ill yoghurt was determined. Lee's agar was used to count Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus when B. lactis were counted in the MRS medium. B. lactis and L. acidophilus in both free and immobilized forms presented satisfactory rates of survival ill milk and acidified milk because the average reduction of the Population was only one log cycle after 21 days of storage. The number of viable cells of immobilized B. lactis in yoghurt presented a gradual decline throughout the storage period, passing from 10(8) cfu/ml to no Count after 28 days of storage. When the Cultures were not in equilibrium just the selective medium was efficient in counting B. lactis ill yoghurt. The results showed that both microorganisms call be added to milk and acidified milk, because their population was only slightly affected during storage. The presence of traditional culture of yoghurt seems to be harmful for Survival of immobilized B. lactis and the immobilization in calcium alginate failed as an effective barrier to protect the cells in all analysed treatments.354167115115

    Qualidade e características sensoriais de manga osmoticamente desidratada com xaropes de açúcar invertido e a sacarose

    Get PDF
    A desidratação osmótica tem se tornado uma tecnologia cada vez mais usual no processamento de alimentos desidratados, por apresentar vantagens como a redução nas perdas de cor e sabor durante o tratamento térmico, inibição do escurecimento enzimático, prescindindo da adição de agentes sulfitantes, e principalmente economia no consumo de energia. Este trabalho avaliou o efeito da utilização de xaropes de açúcar invertido e sacarose como agentes osmóticos na desidratação de manga. As condições utilizadas no processo de desidratação foram: relação xarope/fruto de 3:1(v/p); temperatura de 45ºC e agitação constante. Os frutos in natura e osmo-desidratados foram avaliados quanto ao pH, umidade, atividade de água (a a) e sólidos solúveis (ºBrix). Determinou-se a incorporação de sólidos e a perda de massa após o processo de desidratação. A aceitação sensorial dos frutos in natura e osmo-desidratados foi avaliada através de um teste com escala hedônica, para os atributos aroma, sabor, textura e aceitação global. A desidratação osmótica resultou na redução da umidade e da a a, no aumento do Brix e na manutenção do pH da manga. Os tratamentos com xarope de açúcar invertido ocasionaram mais alterações na umidade, na a a, no Brix, na incorporação de sólidos e na perda de massa comparado ao tratamento com xarope de sacarose. As mangas osmo-desidratadas com o xarope de açúcar invertido (55,3% de taxa de inversão) obtiveram uma aceitação semelhante às mangas in natura, tendo sido considerado o tratamento mais adequado para esse fim.Osmotic dehydration is becoming more popular as a complementary treatment in the processing of dehydrated foods, since it presents some advantages such as minimising heat damage to the colour and flavour, inhibiting enzymatic browning and thus dispensing the addition of sulphite and, mainly, reducing energy costs. The objective of the present study was to evaluate the effect of using inverted sugar and sucrose syrups as osmotic agents in the dehydration of mango. The conditions used in the dehydration process were: syrup/fruit ratio of 3:1 (v/w); temperature of 45ºC and constant stirring. The in natura and osmo-dehydrated fruits were evaluated in relation to pH, moisture content, water activity (a w) and soluble solids (ºBrix). Solids incorporation and loss in mass after the dehydration process were also determined. The sensory acceptance of the in natura and osmo-dehydrated fruits was determined for the attributes of aroma, flavour, texture and overall acceptance using a hedonic scale. Osmotic dehydration resulted in a reduction in moisture content and water activity, an increase in Brix and maintenance of the pH. The treatment with inverted sugar syrup resulted in more significant alterations in moisture content, a w, Brix, solids incorporation and loss in mass than the treatment with sucrose syrup. Mangos osmo-dehydrated with inverted sugar (55.3% inversion rate) syrup obtained acceptance similar to in natura mangos, this treatment being considered the most adequate for dehydration purposes

    Desenvolvimento de queijo minas frescal de leite de búfala com adição de L. acidophilus

    Get PDF
    Effective incorporation of a probiotic into foods requires the culture to remain viable all along processing and storage, without adverse alterations to sensory characteristics. The objective of this work was developing Minas-type fresh cheese with probiotic properties from buffalo milk. Four batches of Minas-type fresh cheese were prepared using buffalo milk: batch T1 in which neither culture nor lactic acid added; batch T3 in which only lactic acid added; batches T2 and T4 , both added of Lactobacillus acidophilus LAC 4, but T4 was also acidified. Resulting cheeses were evaluated for probiotic culture stability, texture profile, sensory acceptance, and changes in pH. The T4 probiotic cheese presented hardness, gumminess, and chewiness significantly lower than the other treatments. However, values for springiness and cohesiveness did not differ between all cheeses, and no sensory differences (p >; 0.05) were found between treatments for texture, taste, and overall acceptance. The addition of probiotic to the acidified cheese (T4) yielded best aroma. The populations of L. acidophilus were greater than 10(6) CFU g-1 after 28 days of storage all products. Minas-type fresh cheese from buffalo milk is a suitable food for the delivery of L. acidophilus, since the culture remained viable during the shelf life of the products and did not negative affect analysed parameters.Para incorporação efetiva de probióticos em alimentos é imprescindível que a cultura mantenha-se viável durante todo o processamento e a estocagem e que não ocorram alterações adversas nas características sensoriais do produto. O objetivo deste trabalho foi desenvolver queijo Minas frescal com propriedades probióticas a partir do leite de búfala. Foram avaliados quatro tratamentos (T1 a T4), sendo T1 e T3 controles, sem e com acidificação, respectivamente em T2 e T4 foram adicionados da cultura probiótica Lactobacillus acidophilus (LAC 4), porém T4 foi também acidificado. Todos os queijos foram avaliados quanto ao perfil de textura, aceitação sensorial e evolução do pH. Nos queijos dos tratamentos T2 e T4 foi determinada a viabilidade da cultura probiótica, durante 28 dias de estocagem refrigerada. O tratamento T4 apresentou valores para dureza, gomosidade e mastigabilidade menores que aqueles obtidos para os demais tratamentos. Não houve diferenças entre os tratamentos (p >; 0.05) em relação à elasticidade, coesividade, assim como para os atributos textura, sabor e aceitação global. O tratamento adicionado de probiótico e ácido foi o melhor aceito em função do aroma. A população de L. acidophilus permaneceu maior que 10(6) UFC g-1 depois de 28 dias de estocagem mesmo no produto acidificado. Queijo Minas frescal de leite de búfala é um alimento adequado para incorporação de L. acidophilus, uma vez que esta cultura permaneceu viável no mesmo durante seu "shelf-life" e não interferiu negativamente nos parâmetros analisados

    Encapsulation of active pharmaceutical ingredients in lipid micro/nanoparticles for oral administration by spray-cooling

    Get PDF
    Nanoencapsulation via spray cooling (also known as spray chilling and spray congealing) has been used with the aim to improve the functionality, solubility, and protection of drugs; as well as to reduce hygroscopicity; to modify taste and odor to enable oral administration; and many times to achieve a controlled release profile. It is a relatively simple technology, it does not require the use of low-cost solvents (mostly associated to toxicological risk), and it can be applied for lipid raw materials as excipients of oral pharmaceutical formulations. The objective of this work was to revise and discuss the advances of spray cooling technology, with a greater emphasis on the development of lipid micro/nanoparticles to the load of active pharmaceutical ingredients for oral administration.This research was funded by the Portuguese Science and Technology Foundation (FCT/MCT) and European Funds (PRODER/COMPETE), under the project reference UIDB/04469/2020 (strategic fund), co-financed by FEDER, under the Partnership Agreement PT2020, granted to Eliana B. Souto. This work was also supported by the National Science Centre within the MINIATURA 4 for a single research activity carried out by Aleksandra Zieli ´nska (grant no: 2020/04/X/ST5/00789), and by the Institute of Human Genetics, Polish Academy of Sciences by the internal grant for the implementation of a single scientific activity.info:eu-repo/semantics/publishedVersio

    Protection of Bifidobacterium lactis and Lactobacillus acidophilus by microencapsulation using spray-chilling

    Get PDF
    The aim of this study was to produce and evaluate solid lipid microparticles containing Bifidobacterium lactis or Lactobacillus acidophilus. Survival assays were conducted to evaluate the resistance of the probiotics to spray-chilling process, their resistance to simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) and their stability during 90 d of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. lactis were resistant to SGF and SIF. The microencapsulation, however, provided protection for L. acidophilus against SGF and SIF. The free and encapsulated microorganisms lost their viability when they were stored at 37 degrees C. However, promising results were obtained when refrigerated and frozen storage was applied. The study indicates that spray-chilling using fat as carrier can be considered an innovative technology and matrix, respectively, for the protection, application and delivery of probiotics. (C) 2012 Elsevier Ltd. All rights reserved.FAPESP in Brazil [Process 2009/11713-2, Process 2009/03140-2

    A new way of valorizing biomaterials: the use of sunflower protein for 1 a-tocopherol microencapsulation

    Get PDF
    Biopolymer based microparticles were efficiently prepared from sunflower protein (SP) wall material and a-tocopherol (T) active core using a spray-drying technique. Protein enzymatic hydrolysis and/or N-acylation were carried out to make some structural modifications to the vegetable protein. Native and hydrolyzed SP were characterized by Asymmetrical Flow Field-Flow Fractionation (AsFlFFF). Results of AsFlFFF confirmed that size of proteinic macromolecules was influenced by degree of hydrolysis. The effect of protein modifications and the influence of wall/core ratio on both emulsions and microparticle properties were evaluated. Concerning emulsion properties, enzymatic hydrolysis involved a decrease in viscosity, whereas acylation did not significantly affect emulsion droplet size and viscosity. Microparticles obtained with hydrolyzed SP wall material showed lower retention efficiency (RE) than native SP microparticles (62-80% and 93% respectively). Conversely, acylation of both hydrolyzed SP and native SP allowed a higher RE to be reached (up to 100%). Increasing T concentration increased emulsion viscosity, emulsion droplet size, microparticle size, and enhanced RE. These results demonstrated the feasibility of high loaded (up to 79.2% T) microparticles

    PERCEPÇÃO DO ENFERMEIRO SOBRE ASSISTÊNCIA ÀS CRIANÇAS COM NECESSIDADES ESPECIAIS DE SAÚDE NA ATENÇÃO PRIMÁRIA

    Get PDF
    RESUMO OBJETIVO: apreender como os enfermeiros da Estratégia Saúde da Família se percebem em relação ao conhecimento e preparo para assistir as crianças com necessidades especiais de saúde e suas famílias e como avaliam o acesso delas aos serviços de saúde. MÉTODOS: estudo descritivo, exploratório de abordagem qualitativa, realizado na atenção primária à saúde. Os dados foram coletados por meio de entrevista semiestruturada com 14 enfermeiros das equipes da Estratégia Saúde da Família. As entrevistas foram transcritas na íntegra e depois submetidas à análise de conteúdo, modalidade temática. RESULTADOS: da análise emergiram duas categorias (despreparo para assistência e suas implicações e acesso aos serviços de saúde da rede de atenção às crianças com necessidades especiais de saúde), as quais mostram que os enfermeiros, em sua maioria, não se sentem capacitados para oferecer assistência de qualidade; avaliam o acesso dessas crianças e suas famílias aos serviços de saúde como dificultado, devido à multiplicidade de condições apresentadas por elas. CONCLUSÃO: a inexistência de protocolo específico e a deficiência no estabelecimento de uma rede que priorize a continuidade, integralidade e qualidade da assistência restringem e dificultam o acesso a exames específicos, consultas com especialistas, além de acompanhamento adequado na atenção primária
    corecore