Study and characterization of a product based on a vegetable extract of quinoa fermented with water kefir grains.

This work aimed to study and characterize a product based on vegetable extract of quinoa (WVEQ) fermented with water kefir grains. The effect of sucrose concentration (SC), inulin concentration (IC), and xanthan gum (XG) concentration were evaluated using a central composite design (CCD) 23. They were subsequently characterized regarding cellular growth of the grains, beverage yield, pH, soluble solids, carbon dioxide (CO2) production, lactic acid, and ethanol production. Therefore, for the final stage, two formulations (F1 and F8) of the CCD were chosen to be characterized in terms of proximate composition, microbiological composition of the kefir culture, analysis of organic compounds, sensory analysis, and enzymatic and microbiological characterization before and after simulation of in vitro gastrointestinal digestion. In the two chosen products, one can see that fermentation optimized the bioavailability of proteins due to the high proteolytic activity of the microorganisms in kefir and the increase in lipid content. In identifying microorganisms, there was a prevalence of Saccharomyces sp. yeasts. In the sensory analysis, the F8 formulation showed better results than the F1 formulation. In vitro, gastrointestinal digestion showed reduced lactic acid bacteria and yeast and increased acetic acid bacteria in the liquid phase for both formulations. In the enzymatic profile, there was a reduction in all enzymes analyzed for both formulations, except for amylase in F1, which went from 14.05 U/mL to 39.41 U/mL. Therefore, it is concluded that using WVEQ as a substrate for the product appears to be a viable alternative with nutritional and technological advantages for serving a specific market niche.

Effect of the addition of Euterpe oleracea Mart. extract on the properties of starch-based sachets and the impact on the shelf-life of olive oil.

This study aimed to produce and characterized active biodegradable packages by extrusion of cassava starch, biodegradable polyester, plasticizer, and acai extract (EA 0, 1, 2, 3 and 4%) and to evaluate its effects on extra virgin olive oil (EVOO) for 120 days. All analyses were performed at the beginning (day 0) and the end of the experiment (day 120). The oil was characterized for acidity index (IA), peroxide index (IP), thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD), phenolic compounds (PC) and color parameters. The incorporation of EA at the initial time caused increased thickness, mechanical properties, solubility in water and oil in all formulations. The some values of properties increased or decreased, due to the interaction of the stored product and packaging. At the end of the storage period, the values of IA and IP were below the limits established by current legislation. The EVOO showed a gradual decrease in PC from day 1 to day 120, for all treatments.

Bioactive Compounds from Jambolan (Syzygium cumini (L.)) Extract Concentrated by Ultra- and Nanofiltration: a Potential Natural Antioxidant for Food.

Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.

Red araçá pulp microencapsulation by hydrolyzed pinhão starch, and tara and arabic gums.

BACKGROUND: Red araçá is a Brazilian native species whose fruits are rich in phenolic acids, flavonoids, anthocyanins, and carotenoids. To preserve the properties of compounds during processing, red araçá pulp (RAP) was encapsulated by hydrolyzed pinhão starch (PS), tara gum (TG), and arabic gum (AG) in different blends in equal proportions, serving as a coating material. RESULTS: Fresh RAP had a gallic acid equivalent of 3098 mg per 100 g of dry weight, 156.29 µg ß-carotene per gram of dry weight, total anthocyanins of 18 mg per 100 g of dry weight and exhibited high antioxidant activity. The highest encapsulation efficiency achieved with the PS, TG, and AG blend was 80.4% for the total carotenoids, and that for the total anthocyanins was 76% with the TG and AG blend. Only one step of antioxidant activity degradation was identified, and the carrier system PSTG was efficient at maintaining the antioxidant activity, with half-life of 23.60-37.27 days. CONCLUSION: The use of PS alone as a coating material or associated with TG and AG gums resulted in improved retention of bioactive compounds, these being an excellent alternative coating material since they improved the stability of the antioxidant activity of RAP. © 2020 Society of Chemical Industry.

The use of electrothermal vaporizer coupled to the inductively coupled plasma mass spectrometry for the determination of arsenic, selenium and transition metals in biological samples treated with formic acid.

A fast method for the determination of As, Co, Cu, Fe, Mn, Ni, Se and V in biological samples by ETV-ICP-MS, after a simple sample treatment with formic acid, is proposed. Approximately 75 mg of each sample is mixed with 5 mL of formic acid, kept at 90°C for 1 h and then diluted with nitric acid aqueous solution to a 5% (v/v) formic acid and 1% (v/v) nitric acid final concentrations. A palladium solution was used as a chemical modifier. The instrumental conditions, such as carrier gas flow rate, RF power, pyrolysis and vaporization temperatures and argon internal flow rate during vaporization were optimized. The formic acid causes a slight decrease of the analytes signal intensities, but does not increase the signal of the mainly polyatomic ions ((14)N(35)Cl(+), (14)N(12)C(+), (40)Ar(12)C(+), (13)C(37)Cl(+), (40)Ar(36)Ar(+), (40)Ar(35)Cl(+), (35)Cl(16)O(+), (40)Ar(18)O(+)) that affect the analytes signals. The effect of charge transfer reactions, that could increase the ionization efficiency of some elements with high ionization potentials was not observed due to the elimination of most of the organic compounds during the pyrolysis step. External calibration with aqueous standard solutions containing 5% (v/v) formic acid allows the simultaneous determination of all analytes with high accuracy. The detection limits in the samples were between 0.01 (Co) and 850 µg kg(-1) (Fe and Se) and the precision expressed by the relative standard deviations (RSD) were between 0.1% (Mn) and 10% (Ni). Accuracy was validated by the analysis of four certified reference biological materials of animal tissues (lobster hepatopancreas, dogfish muscle, oyster tissue and bovine liver). The recommended procedure avoids plasma instability, carbon deposit on the cones and does not require sample digestion.