Estudio microbiológico y estructural de papas deshidratadas por métodos combinados y envasadas en atmósfera modificada

Teniendo en cuenta los hábitos actuales de consumo de alimentos mínimamente procesados, en este trabajo se analizaron los resultados microbiológicos y estructurales de papas secadas por métodos combinados (microondas y convección con aire caliente) pretratadas por deshidrataciónosmótica, las que posteriormente fueron envasadas en bolsas de material multicapa (polietilenopoliamida-polietileno) en atmósfera modificada (70 % de N2 y 30 % de CO2) y conservadas en refrigeración a 4 ºC. El pretratamiento consistió en la deshidratación osmótica de cubos de papas de 1 cm de arista en una solución de xilitol al 40 % m/m y de cloruro de sodio al 5 % m/m a una temperatura de 40 ºC. Posteriormente, las papas fueron llevadas al equipo de microondas, el que se hizo operar en condiciones de secado combinado, microondas junto con convección con aire caliente a una potencia de 60 % respecto de la máxima del equipo. El producto obtenido es conservado en atmósfera modificada y refrigeración. El mismo requiere para su consumo una posterior rehidratación y cocción en un tiempo mínimo con agua en ebullición. Este tiempo se estimó en 5 min aproximadamente, luego de ensayos de rehidratación y sensoriales.Considering current habits of consumers, the minimally processed foods were analyzed by the mycrobiological and structural results of the potatoes dryed by combined dry (microwave and hot air convection), pretreated by osmotic dehydration which were latter packaged into multilayers bags (polyethylene-polyamide-polyethylene) under modified atmosphere (70 % of N2 and 30 % of CO2) and preserved in refrigeration at 4 ºC. Pretreatment consists of osmotic dehydration of cubes of potatoes of 1 cm of edge in a solution of xylitol 40% m/m and sodium chloride 5% m/mat a temperature of 40 °C. Then, potatoes were dryed in the microwaves equipment, in conditions of combined drying, microwave and convection with hot air at a power of 60 % from the maximum power of the microwave equipment. The obtained product is preserved in a modified atmosphere and cooling. For consumption, later it requires rehydration and cooking in a minimum time with boiling water. This time was estimated at 5min, after rehydration and sensory tests.Fil: Mateucci, Ricardo Rafael. Universidad Tecnológica Nacional; ArgentinaFil: Della Rocca, Patricia Andrea. Universidad Tecnológica Nacional; ArgentinaFil: Mascheroni, Rodolfo Horacio. Universidad Tecnológica Nacional; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin

Effect of decontamination treatment on the quality of dehydrated thyme, coriander, and mustard

The objective of this work was to evaluate the effects of different decontamination treatments on the quality of dehydrated thyme, coriander, and mustard. Treatments applied were: (i) ultraviolet radiation treatment irradiation; (ii) steam, (iii) steam–ultraviolet radiation treatment; (iv) humidification–ultraviolet radiation treatment, and (v) steam–humidification–ultraviolet radiation treatment. Their effectiveness to control indigenous aerobic mesophiles and yeasts and molds population was assessed by plate count. The effect of proposed treatments on total polyphenol contents and antioxidant activity was also evaluated. Furthermore, the effect of treatments on spices performance to prevent canola oil oxidation was also analyzed. The use of steam– ultraviolet radiation treatment in aqueous medium was the most effective for decontamination, reducing the aerobic mesophiles and yeasts and molds counts between 1.0 and 2.2 log CFU/g dry spice. This treatment decreased significantly the polyphenol content and the antioxidant capacity of the three spices analyzed. However, in the case of mustard, the residual antioxidant compounds were able to control canola oil oxidation more efficiently than butylated hydroxytoluene. Results suggest that the use of steam–ultraviolet radiation treatment in aqueous medium can be useful in food preservation processes.Fil: Ferriccioni, Natalia. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Mateucci, Ricardo Rafael. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Zangrando, Agustina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Santana, Susana Noemi. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Campos, Carmen Adriana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; Argentin

Chlorella vulgaris cultivation using ricotta cheese whey as substrate for biomass production

The batch production of Chlorella vulgaris and its potential to profit the remnant nutritional components from ricotta cheese whey (RCW) were evaluated. From a first screening test, undiluted ricotta cheese whey was selected to be used as a growth media in the subsequent assays. Three different RCW pre-treatment methods were tested and compared: centrifugation, heat treatment (HT) and tangential flow microfiltration (TFMF). Based on the results of the screening test, a macronutrient supplementation assay was performed to increase the biomass production. A central composite design was used to analyse the effect of supplementing the media with nitrogen (0; 3.3 and 6.6 g L−1) and phosphorous (0; 0.27 and 0.55 g L−1). Chlorella vulgaris was able to grow in all tested RCW concentrations. All RCW pre-treatment methods resulted in an enhancement of the growth kinetic parameters (GKP) of Chlorella vulgaris. Among them, TFMF technology presented the best performance. The macronutrient supplementation did not show an enhancement in GKP. The scaled-up production until 400 mL batch using micro-filtered RCW showed a μmax value of 0.41 ± 0.05 h−1 (9.9 ± 1.2 day−1), a lag period of 19.9 ± 0.7 h and a Cmax of 2.52 ± 0.09. A final biomass concentration of 2.28 g L−1 was obtained. In addition, chemical oxygen demand (COD), phosphorus and nitrogen removals of 26 ± 1%, 75 ± 1% and 55 ± 1% were respectively achieved. The use of TFMF and Chlorella vulgaris cultivation represents a sustainable proposal for contributing to the circular economy.Fil: Casá, Nahuel Esteban. Universidad Tecnológica Nacional; ArgentinaFil: Lois Milevicich, Julieta. Universidad Tecnológica Nacional; ArgentinaFil: Alvarez, Paola. Universidad Tecnológica Nacional; ArgentinaFil: Mateucci, Ricardo Rafael. Universidad Tecnológica Nacional; ArgentinaFil: de Escalada Pla, Marina Francisca. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad Tecnológica Nacional; Argentin

Chlorella vulgaris biomass production using brewery wastewater with high chemical oxygen demand

The aim of the work was to use an effluent with high chemical oxygen demand (COD) from small brewery as substrate for the production of Chlorella vulgaris biomass. A non-axenic strain from a Patagonian river was employed, and the effects of COD and pH value on the microalga growth were studied through a central composite design. A medium with COD 18300 mg O2 mL−1 and initial pH: 6.5 optimized microalga growth. With the optimal condition, C. vulgaris adapted rapidly to medium and stationary phase was attained at 75 h. Moreover, lack of illumination did not affect μmax, neither final biomass concentration, while supplementation with BG11 enhanced the biomass productivity at 0.47 ± 0.07 g L−1 h−1, and pigment contents at least four times respect to the heterotrophic mode. For the first time, a brewery wastewater with high COD could be successfully used as substrate for C. vulgaris production, without presenting inhibitions, which represents a significant advance contributing toward more sustainable promising perspectives.Fil: Lois Milevicich, Julieta. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Casá, Nahuel Esteban. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Alvarez, Paola. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Mateucci, Ricardo Rafael. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: Busto, Víctor Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Nanobiotecnología. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Nanobiotecnología; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; ArgentinaFil: de Escalada Pla, Marina Francisca. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentina. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentin