Abstract Extraction of compounds from microalgae requires cell disruption as a pretreatment to increase extraction yield. Botryococcus braunii is a microalga with a significant content of carotenoids and other antioxidant compounds, such as chlorophylls. Cell disruption of B. braunii using CO2 rapid depressurization was studied as a pretreatment for the extraction of carotenoid and chlorophyll pigments. We studied the effect of temperature (21–49 °C) and pressure (6–13 MPa) during static compression on pigment recovery with supercritical CO2 at 40 °C, 30 MPa and solvent flow of 4.7 L NPT/min. Within the experimental region, the extraction yield of carotenoids and chlorophylls increased by 2.4- and 2.2-fold respectively. Static compression conditions of high pressure and low temperature increased the extraction of carotenoids and especially chlorophylls. We selected 21 °C and 13 MPa as the cell disruption condition, which produced 1.91 g/kg d.s. of carotenoids and 14.03 mg/kg d.s. of chlorophylls. Pretreated microalga gave a 10-fold higher chlorophyll extraction yield compared to the untreated sample. While for carotenoids and tocopherols were 1.25 and 1.14-fold higher, respectively. Additionally, antioxidant activity of pretreated microalga (33.22 mmol TE/kg oil) was significantly higher than the value for the untreated samples (29.11 mmol TE/kg oil) (p ≤ 0.05). Confocal microscopy images showed morphological differences between micro-colonies with and without disruption treatment, suggesting that partial cell disruption by rapid depressurization improved the extraction of microalga compounds.

Se estudió el efecto individual y combinado del escaldado a baja temperatura (solución 1% de ácido cítrico, 50ºC por 30 segundos) y la humectación con solución de glicerol (3% p/p, 20 segundos), sobre la calidad de zanahorias frescas peladas y pre-cortadas. Se establecieron cuatro tratamientos: (T1) inmersión por 30 segundos en agua destilada (testigo); (T2) muestras escaldadas; (T3) muestras humectadas con glicerol; (T4) muestras escaldadas y humectadas con glicerol. Durante el almacenamiento de las muestras se evaluó el cambio en el contenido de pigmentos carotenoides, color, sólidos solubles y pérdida de peso. Los tratamientos no afectaron significativamente el cambio en los pigmentos carotenoides (p>0,10) y sólidos solubles (p>0,05); pero sí la pérdida de peso (p<0,05) y el color (p<0,05). Tratamientos que incluyeron muestras escaldadas (T2 y T4) indujeron menos cambios en la intensidad del color naranja en comparación a los tratamientos T1 y T3 (p<0,05).

Effect of blanching and hygroscopic coating on quality of fresh-cut carrots (Daucus carota var. chantenay) during storage. The effect of blanching at low temperatures (solution 1% acid citric, 50°C for 30 seconds) and the application of glycerol as humectant (3% p/p, 20 seconds) to preserve the quality of fresh-cut carrots (Daucus carota) were studied as individual or combined treatments. Four treatments were evaluated: a control by dipping samples for 30 seconds in distilled water (T1); blanching (T2); glycerol application (T3); and blanching plus glycerol application (T4). Total carotenoids content, color, soluble solids and weight loss were monitored during storage. Results showed no differences between treatments in carotenoids content (p>0,10) and soluble solids (p>0,05). However, differences were observed between treatments in weight loss (p<0,05) and color change (p<0,05). Blanched samples (T2 and T4) showed small changes in orange color intensity compared to treatments T1 and T3 (p<0,05).

Se aplicó un recubrimiento comestible basado en carboximetilcelulosa y ácido esteárico sobre pimentones verdes (Capsicum annuum L.), para determinar su efecto como agente protector y estabilizador de las características naturales del fruto. Los pimentones se dividieron en tres lotes de acuerdo al tratamiento: (T1) sin recubrir; (T2) con recubrimiento en la base del pedúnculo o tallo; (T3) recubrimiento sobre toda la superficie del fruto, y se almacenaron a 5± 1ºC por 28 días. Durante este tiempo se evaluó la calidad sensorial y la pérdida de peso. Características sensoriales tales como el color, apariencia, firmeza y calidad, se evaluaron mediante una prueba de puntaje compuesto, en la que participa un panel de 10 jueces entrenados (p>0,05). Al final del estudio, los pimentones del tratamiento T3 mostraron mejor estabilidad sensorial que el control T1 (p<0,05); no observándose ningún cambio significativo entre T2 y T3. Los pimentones recubiertos mostraron menor deterioro de la firmeza comparado con el control. El color fue el atributo que experimentó menor cambio, no existiendo diferencias significativas entre los tratamientos (p>0,05)

Edible coating effects on the sensory quality of green bell pepper fruits (Capsicum annuum L.) during storage. Edible coating based on carboxymethyl cellulose (CMC) and stearic acid were applied on green bell peppers (Capsicum annuum L.) samples in order to investigate its effects as protecting agent to enhance natural characteristics of products. Samples were submited to three lots according to: (T1) uncoated; (T2) coated in lower part of the stem; (T3) coated all over the surface (T3). During storage at 5 ± 1ºC, for 28 days, sensory quality and weight loss were evaluated. Sensory characteristics such as color, appearance and firmness were controlled using a composite scoring test. At the end of the study, T3 treatment showed better sensory stability than T1 (p<0.05), none significant changes between T2 and T3 were found. The coated samples showed less firmness deterioration compaired with control samples. The color was the attribute that changed less, without significant difference between treatments (p>0.05)

Se optimizó la formulación de premezclas en polvo de queque y bizcocho dietéticos, aplicando la metodología superficie de respuesta (MSR). La calidad sensorial fue determinada para ambas formulaciones utilizando el método de puntaje compuesto con un panel entrenado de 18 jueces. Las variables seleccionadas para queque fueron: % agente emulsionante y tiempo de horneo; y para bizcocho % agente emulsionante y % harina clorada. Analizando el mapa de contorno y teniendo en cuenta aspectos económicos se determinó que la mejor respuesta para la formulación de queque dietético, estuvo dada por la combinación de variables: agente emulsionante 2% y 48 minutos de tiempo de horneo. Para el caso del bizcocho dietético, los niveles óptimos fueron agente emulsionante 6.2% y harina clorada 48.2%. Ambos productos demostraron ser estables bajo condiciones aceleradas de almacenamiento de 30°C durante 75 días, no encontrándose diferencias sensoriales significativas (p<0,05) en los productos horneados con relación a formulaciones recién preparadas. El índice de peróxido se mantuvo por debajo de los valores señalados por la bibliografía para detectar rancidez organoléptica. Datos obtenidos por la prueba hedónica muestran que estos productos dietéticos tienen una buena aceptabilidad, ampliando por consiguiente el rango de oferta de productos dietéticos de pastelería para satisfacer demandas del mercado actual.

Optimization of dietetic formulations for pastry products. Optimized formulations of dietetic pastry products such as cake and sponge cake premixes were formulated using the surface response methodology. % Emulsifier agent and baking time were the selected independent variables for cake, as well as % emulsifier agent % chlorinated flour the variables selected for sponge cake. Three different level of each variable summing up thirteen experimental formulae of each product were assessed to optimize the variables that could have some influence in the sensory characteristics of these dietetic products. The total sensory quality was determined for both dietetic products using the composite scoring test and a panel of 18 trained jugdes. Lookin at the contour graphic and considering economic aspects the best combination of variables for cake formulation was 2% emulsifier agent and 48 minutes for baking time, With respect to sponge cake, the best combination was 6% emulsifier agent and 48% chlorinated flour. Shelf life studies showed that both dietetic formulations remained stable during storage conditions of 75 days at 30°C. During this period, significant differences in sensory characteristics were not found (p<0.05). Data of peroxide values were kept under the critical value reported for detection of organoleptic rancidity. Reported values of hedonic test showed that these dietetics pastry products had good acceptability, and open up marketing opportunities for new produtcs with potencial health benefits to consumers.