Squalene Extraction by Supercritical Fluids from Traditionally Puffed Amaranthus hypochondriacus

Extraction of squalene, a potent natural antioxidant, from puffed A. hypochondriacus seeds was performed by supercritical fluid extraction (SCFE); besides, to have a blank for comparison, extraction was performed also by Soxhlet method using organic solvents (hexane). Chemical proximal composition and seed morphology were determined in raw, puffed, and SCFE-extracted seeds. Extracts were obtained with a 500 mL capacity commercial supercritical extractor and performed between 10 and 30 MPa at 313, 323, and 333 K under constant CO2 flow of 0.18 kg CO2/h during 8 h. The squalene content was determined and the fatty acids present in the extracts were identified by GC-MS. The extract obtained by SCFE from puffed amaranth seeds reached 460 ± 28.1 g/kg squalene in oily extract at 313 K/20 MPa

Revalorization of cactus pear (Opuntia spp.) wastes as a source of antioxidants

Recently, an increased interest in antioxidant activity and health-improving capacity of cactus pear has been registered. The antioxidant capacity of the pulp of cactus-pear fruits has been previously assessed. In this work, total phenolics, flavonoids and tannins of peel and seeds of four cactus pear cultivars were examined as well as their antioxidant capacity. Tannins were the major phenolics in cactus pear seeds accounting for almost fifty percent for all cultivars. Analysis of variance revealed that ripeness, cultivar, and its interaction had highly significant effect on the total phenolics, tannin, and flavonoid contents of cactus pear peel. With regard to the seeds, only the stage of ripeness and interaction (ripeness stage x cultivar) were significant on total phenolics and tannins contents. The flavonoid content in seeds was not affected by any of the factors or their interactions. The antioxidant capacity was higher in the peel than in the seeds. Generally, fruits with light-green or yellow-brown peel have higher antiradical activity and Trolox equivalent antioxidant capacity (TEAC) values compared with those with red-purple peel. Cactus pear by-products can indeed be exploited as a good and cheap source of natural antioxidants

Evaluación de la capacidad antioxidante, características fisicoquímicas y perfil sensorial de Opuntia robusta y O. ficus-indica

Las Opuntia spp. son un recurso fitogenético Mexicano de gran valor nutritivo y alto contenido de betalaínas, compuestos conocidos por sus propiedades antioxidantes. Este estudio evaluó las características fisicoquímicas, el contenido de betalaínas y su capacidad antioxidante (CA), así como el perfil sensorial de frutos de O. robusta y O. ficusindica. Esta última presentó mayor acidez y contenido de sólidos solubles (F= 769,2; P= 0,0001), (F= 360,4; P ≤0,0001), que O. robusta. En humedad y contenido de cenizas no hubo diferencias significativas entre ambas especies. La concentración de betalaínas fue superior en Opuntia robusta (F=529,1; P= ≤0,0001) betacianinas (0,114 mg/mL pulpa) y betaxantinas (0,073 mg/ mL de pulpa), en O. ficus-indica (0,023 mg/ mL de pulpa y 0,0198 mg/ mL de pulpa). Se encontraron diferencias significativas en la CA (F=545,9; P ≤0,0001), en O. ficus-indica hasta 195,38 µmol equivalente Trolox/ mL por el método Ácido2, 2´-azino-bis-(3-etilbenzotiazolina)6-sulfónico (ABTS) y 22% de inhibición de radicales libres por el método 2,2 difenil-1-pricrilhidrazilo (DPPH), para O. robusta 165,6 µmol equivalente Trolox/ mL y más del 36% de inhibición de radicales libres. Los resultados mostraron que la CA está directamente relacionada con la concentración de betacianinas y betaxantinas. Ambas variedades de Opuntia exhiben una tendencia a lo dulce y ácido, con aromas, sabores y resabios con notas frutales y vegetales. Estos resultados sugieren que estas especies pueden ser empleadas para la extracción de betalaínas debido a su gran potencial para utilizarse en la industria como fuente de pigmentos naturales con propiedades antioxidantes y agradables características sensoriales.Opuntia spp. are a Mexican phytogenetic resource with great nutritive value and high betalains (compounds known for their antioxidant properties) content. Our main goal was to evaluate the physicochemical characteristics, betalains concentration and antioxidant capacity (AC), as well as sensory profiles of Opuntia robusta and O. ficus-indica, where the later one showed higher acidity and soluble solids content (F= 769.2; P= 0.0001 and F= 360.4; P ≤0.0001 respectively) than O. robusta. There was no significant difference between the species in terms of humidity and ash content. Betalains concentrations were higher in Opuntia robusta (F=529.1; P= ≤0.0001), while betacyanins (0.114 mg/ mL pulp) and betaxantins (0.073 mg/ mL de pulp) were higher in O. ficus-indica (0.023 mg/ mL pulp and 0.0198 mg/ mL de pulp). Significant differences for AC were found (F=545.9, P ≤0.0001), with O. ficus-indica showing up to 195.38 µmol Trolox equivalent / mL by the method 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 22% of free radicals inhibition by the method 2, 2 diphenyl-1-pricrylhydrazyl (DPPH), while 165.6 µmol Trolox equivalent / mL and more than 36% free radicals inhibition were found for O. robusta. Results showed that the antioxidant capacity is directly related with betacyanins and betaxantines concentration. Both Opuntia varieties exhibit a tendency to sweetness and acidity, with aromas, flavors and scents within fruity and vegetable notes. These results suggest that both species could be used in the extraction of betalains due to their great industrial potential as a source of natural pigments with antioxidant properties and pleasant sensorial characteristics

Effect of the Instant Controlled Pressure Drop Technology in Cardamom (Elettaria cardamomum) Essential Oil Extraction and Antioxidant Activity

Green cardamom (Elettaria cardamomum) is an outspread spice native to Asia, which is well appreciated for its sensory characteristics, delicate aroma, and unique taste. Currently, the main cardamom extracts are essential oils (EOs), and regarding current market tendencies, this market is in high growth. For this reason, technologies such as the instant controlled pressure drop (DIC) have been applied to reach higher yields and better quality of EO. Then, this study explores the impact of DIC as a pretreatment before hydrodistillation (HD) on the EO yield and their antioxidant activity. Obtained results showed that the coupling of DIC-HD increased the yield of essential oil and also had a positive impact on their antioxidant capacity. The EO yield of DIC-HD (140 °C and 30 s) was 4.43% vs. 2.52% for control; the AOX of DIC-HD (165 °C and 30 s) was 86% inhibition vs. 57.02% for control, and the TEAC of DIC-HD (140 °C and 30 s) was 1.44 uMTE/g EO vs. 13.66 uMTE/g EO

Effect of aqueous, acid and alkaline thermal treatments on antinutritional factors content and protein quality in Lupinus campestris seed flour

Lupinus campestris seeds grown in Mexico have a similar composition to soybean (44% protein, 13% lipids). Use of lupin seed in human and animal diets is limited by its quinolizidine alkaloids (QAs) and other antinutritional factor contents. The effect of aqueous, acid and alkaline thermal debittering treatments with L. campestris seeds flour was evaluated on QAs, oligosaccharides (RFOs), and phenolic compounds (PCs) contents, as well as protein quality. The alkaline treatment most effectively eliminated QAs. Protein content increased from 430 g/kg in untreated seeds to 543 in the aqueous treatment, 567 in the alkaline treatment and 563 g/kg in the acid treatment. RFOs were eliminated in all treatments. The obtained sample with alkaline treatment had the best protein quality (2.04); this value was 17% lower than that of casein (2.45). The apparent digestibility was over 90% in all treatments, with the aqueous treatment exhibiting the best value (93%). © 2010 American Chemical Society

A Preliminary Study on the Effect of the Instant Controlled Pressure Drop Technology (DIC) on Drying and Rehydration Kinetics of Maize Kernels (Zea mays L.)

Maize is one of the three worldwide cereal crops with the most outstanding production; however, its postharvest losses range from 2 to 40% due to inadequate harvesting, drying, and storage technologies. This study focuses on the Instant Controlled Pressure Drop technology (DIC) effect on maize kernels’ drying and rehydration kinetics. In total, 19 different DIC treatments were carried out on maize kernels (~25% d.b.). The DIC parameters studied were steam pressure (0.1 to 0.4 MPa) and treatment time (10 to 90 s). After DIC treatment, drying kinetics were carried out by Convective Air Drying (CAD) at 50 °C and 0.4 ms−1 airflow. Rehydration kinetics and Water Holding Capacity (WHC) were evaluated at 20 °C. In comparison to CAD samples, DIC (0.4 MPa and 90 s) reduced the drying time from 180 min to ~108 min. Additionally, regarding the rehydration and WHC results, DIC achieved the same moisture content in only 3.5 min that controls achieved after 1 h of rehydration (0.40 g H2O/g dry matter). Moreover, DIC (0.4 MPa and nine cycles of 10 s) increased the WHC 2.3 times compared to the control. In this way, DIC could be a postharvest technology to improve maize kernels’ drying operations and functional properties

Evaluation of Biological, Textural, and Physicochemical Parameters of Panela Cheese Added with Probiotics

Biological, physicochemical and textural parameters of a Panela cheese with and without probiotics (LSB-c and C-c) were analyzed during 15 days of storage at 4 °C. Changes in cohesiveness, hardness, springiness, and chewiness were measured by texture profile analysis. Additionally, moisture, pH, nitrogenous fractions (nitrogen soluble in pH 4.6, non-protein nitrogen, 70% ethanol-soluble nitrogen, and water-soluble extract) were evaluated. The peptide profile of nitrogenous fractions was also analyzed. Finally, biological activity was evaluated by ABTS (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and DPPH (2,2-diphenyl-1-picrylhydrazyl), as well as the Inhibition of Angiotensin-Converting Enzyme. Analysis of variance showed significant differences for most of the evaluated parameters. By principal component analysis (PCA), two groups were separated, one corresponding to LSB-c and the other corresponding to C-c. The separation was given mostly by hardness, chewiness, and ABTS of all nitrogenous fractions. LSB-c showed higher biological activities than C-c

Antioxidant and angiotensin-converting enzyme inhibitory activity in fresh goat cheese prepared without starter culture: a preliminary study

Proteolysis is specific for each type of cheese and might be affected by heat treatment. Studies have shown the ability of cheeses to produce bioactive peptides with antioxidant or anti-hypertension bioactivities, which have been related to ripening time or activity of starter cultures, however, little is known about their production in fresh cheeses. Our objective was to evaluate antioxidant and angiotensin-converting enzyme inhibitory (ACEI) activities in fresh goat cheeses elaborated without starters using pasteurized and raw milk from different seasons. Proteolysis was measured by acid-soluble nitrogen, non-protein nitrogen and ethanol-soluble nitrogen indexes, using the Kjeldahl method and reverse phase high performance liquid chromatography (RP-HPLC). Each fraction’s antioxidant and ACEI activities were measured. Analysed cheeses showed high biological activities and slight differences between them were associated with heat treatment. Our results suggested that fresh goat cheese had important biological activity due to peptides present originally in the milk or released by rennet action during cheese manufacture