No abstract

Ultrasonic-assisted extraction (UAE) of the oil from the seeds/peel mixture of pumpkin using ethanol as solvent was investigated. The effects of the ultrasound, solvent volume, time, and temperature on the oil yield were evaluated. Oil extraction from the seeds by ultrasound and the mixture by Soxhlet extraction (SE) was also performed. The use of ultrasound and higher availability of ethanol (up to 6 mL g −1 sample) favored the oil removal. In the extraction kinetics, the washing step was verified in the first 20 min, corresponding to 79-89% of the total oil yield. The diffusion coefficient increased from 30 to 75 C, as well as the spontaneity of the extraction, achieving 71% of the SE. Linoleic and oleic acids were found in higher concentrations in the oils. UAE made possible the greater extraction of β-carotene, tocopherols, and fistosterois, and the peel addition provided higher contents of these compounds.

This study investigated the extraction of betalains from red beet by an ultrasoundassisted process using water as solvent. For this purpose, the effect of time and temperature on ultrasound-assisted extraction (UAE) was evaluated, and together the effect of ultrasound on the process was investigated by comparing the results with orbital shaking extraction (OSE). From the ideal conditions of these parameters, defined in the UAE, the effects of the ultrasound power and the solvent/sample ratio were evaluated and the experimental data obtained in the kinetics with different solvent/sample ratios were correlated with the diffusion coefficient of betalain in water. The results showed that the betalains content present in the extract decreased with temperature and the same occurred with the increase in time at higher temperatures, therefore, 30°C and 30 min were the first conditions established. Under these conditions, the UAE showed better results in obtaining betalain compared to OSE. The increase in ultrasound power improved the extraction and 83 W was sufficient for maximum removal of the compounds. The highest betalains content was obtained using solvent/sample ratio of 75 ml/g and this result is attributed to the highest diffusion coefficients determined in this condition. This extract showed high sugar content, being sucrose the main component (~96%), and also exhibits high antioxidant activity by ABTS, DPPH, and FRAP methods.

The objective of this work was to evaluate the efficacy of ethyl acetate as a solvent in the extraction of macauba kernel oil (MKO) using ultrasonic-assisted extraction (UAE). It was shown that more MKO oil could be extracted with the use of larger amounts of solvent, higher temperatures and longer extraction times. Thus the maximum oil yield (40.61%) was obtained by UAE at 60 °C for 45 min, using a solvent to kernel ratio of 12 (mL g-1), obtaining a higher yield than that obtained with n-hexane under the same experimental conditions. UAE was favorable for this oil extraction (p < 0.05), presenting a yield close to that reported for classical extraction but with a shorter extraction time and smaller solvent volume. Lauric acid corresponded to ~44% of the MKO composition. The oils presented low free fatty acid contents (<0.80% wt), and the phytosterols, campesterol and β-sitosterol, were identified in the MKO with higher levels in the oil obtained by UAE.

The aim of this study was to evaluate the effect of hydrolysate collagen (HC), cheese whey (CW), and açaí pulp (AP) content on the characteristics of probiotic dairy beverages. Higher levels of CW and AP decreased beverage ash and protein content, and increased lipid and carbohydrate content and energy values. HC and AP positively affected the viscosity of the formulations, which exhibited pseudoplastic behavior. In terms of quality parameters, higher levels of CW and AP increased both the syneresis (2.56–5.74%) and sedimentation index values (1.80–1.87%) of the formulations. The beverages presented adequate stability of physicochemical and microbiological parameters during 28 days storage. Formulations containing average levels of CW (22.5%), AP (30%), and HC (1.0%) achieved the best results regarding sensory analysis, with acceptability index values above 70% for most parameters. Practical applications Demand for probiotic foods is currently increasing due to their potential health benefits. Although the utilization of cheese whey in dairy beverage development is a challenge to the food industry because of the viscosity of the final product, this situation can be improved via the use of selected ingredients. Açaí pulp, hydrolyzed collagen, and cheese whey, when used in the production of probiotic dairy beverages, offer to the market a new functional product of adequate quality and acceptability.