No abstract

This study evaluates the use of spray drying to produce microparticles of Lactobacillus casei. Microorganism was cultivated in shaken flasks and the microencapsulation process was performed using a laboratory-scale spray dryer. A rotational central composite design was employed to optimise the drying conditions. High cell viability (1.1 × 10(10) CFU/g) was achieved using an inlet air temperature of 70 °C and 25% (w/v) of maltodextrin. Microparticles presented values of solubility, wettability, water activity, hygroscopicity and humidity corresponding to 97.03 ± 0.04%, 100% (in 1.16 min), 0.14 ± 0.0, 35.20 g H2O/100 g and 4.80 ± 0.43%, respectively. The microparticles were spherical with a smooth surface and thermally stable. Encapsulation improved the survival of L. casei during storage. After 60 days, the samples stored at -8 °C showed viable cell concentrations of 1.0 × 10(9) CFU/g.

RESUMO -Resíduos agroindustriais, provenientes da extração de sucos de frutas cítricas, são ricas fontes de substâncias pécticas. Objetivando o aproveitamento desses resíduos como uma alternativa de baixo custo para a produção de biopolímeros, foi estudado o uso de hidrolisados pécticos para crescimento celular e produção de polihidroxialcanoatos por Cupriavidus necator. Nesse trabalho foi empregada uma pectina cítrica comercial (Vetec ® ) e uma endo-poligalacturonase (Sigma ® ), sendo realizado um estudo das condições de hidrólise que favorecessem a obtenção de compostos redutores (CR) por meio da aplicação de planejamento fatorial e metodologia de superfície de resposta. As variáveis investigadas foram a concentração de enzima e a agitação, mantendo-se a concentração de substrato em 1% (p/v). Os resultados obtidos foram comparados com a performance enzimática realizada a uma maior concentração de substrato (10% p/v) empregando-se diferentes concentrações de enzima. Ambos os resultados indicaram que a concentração enzimática de 10 UI/g de pectina favoreceu a obtenção de CR, permitindo atingir em média 70 g/L de CR a partir de 100 g/L de pectina. O meio de cultura formulado a partir desse hidrolisado foi satisfatório para o crescimento celular de C. necator, sendo obtida uma concentração de células acima de 10 g/L e o acúmulo intracelular de polihidroxialcanoatos.

Incorporação de Lactobacillus casei microencapsulado em queijo tipo coalhoIncorporation of encapsulated Lactobacillus casei into type curd cheese

No abstract

Brazil is the world's largest producer of orange and passion fruit, which are destined mainly for industrialization, generating grand volumes of wastes. The solid portion of these residues is a rich source of pectin -composed mainly of galacturonic acid and neutral sugars, which through the hydrolysis process can be used in biological conversion processes, as the production of polyhydroxyalkanoates (PHAs). This way, we characterized these wastes, followed by the extraction and hydrolysis of pectin for employ as a substrate for the cell growth of Cupriavidus necator. The results confirmed the large portion of pectin (almost 40 g.100g -1 ) and soluble sugars, present in these wastes. The hydrolyzed extract showed as a good source of carbon for the cell growth of C. necator with Y X/S 0.56 and 0.44, µ Max 0.27 and 0.21 for orange and passion fruit wastes respectively, similar to other carbon sources. This way, the extraction and hydrolysis of orange and passion fruit wastes for the cellular growth of C. necator, can be a good alternative to converting of residues in high value added product. ORCid: https://orcid.org/0000-0002-5109-7485 INTRODUTIONThe increase in world population and the awareness of a healthier lifestyle have enhanced the fruit and vegetables consumption. In this scenario, Brazil stands out between the major producers of fruits and juices, being the world's largest producer of oranges (17,251,291 tons) and passion fruit (703,489 tons) in 2016 (IBGE 2016).

How to cite: lOCATellI gO, FINKleR l AND FINKleR Cll. 2019. Comparison of acid and enzymatic hydrolysis of pectin, as inexpensive source to cell growth of Cupriavidus necator. An Acad Bras Cienc 91: e20180333.

The aims of the study were to develop and apply alginate and pectin-based edible coatings on minimally processed mango (Mangifera indica L.) variety 'Espada'. A full experimental design was performed using alginate, pectin and glycerol concentrations as independent variables and total soluble solids as response variable. Minimally processed mango was immersed in each film forming solution, calcium chloride and glycerol solutions pretreated with 1% (w/v) solution of ascorbic acid, dried at 25 ± 2 °C for 24 h and then refrigerated at 8 ± 1 °C for 14 d. Based on the results of the experimental design, the following formulations were evaluated: 2% (w/v) alginate/3% (w/v) pectin (with and without glycerol) and 3% (w/v) alginate/ 0.5% (w/v) pectin (with and without glycerol). Fruits coated with biopolymers had lower total soluble solids content and titratable acidity compared to the control group. The formulation containing 2% (w/v) alginate, 3% (w/v) pectin and 5.5% (w/v) glycerol showed the best performance for long-term refrigerated storage of minimally processed mango for a period of 16 d.