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The disposal of effluents from food industries into surface waters represents a serious environmental problem, mainly due to the presence of dyes in their composition, which alters the photosynthetic capacity of aquatic plants. In addition, many of the by-products generated by their degradation can be toxic and non-biodegradable. In this research, a photocatalytic reactor constructed from quartz tubes was designed and built to be applied in an advanced oxidation processes (UV/TiO2), for the degradation of indigo carmine blue food dye, in an aqueous solution. A factorial design 2³ was performed, where three variables were studied: the dye concentration (20 and 30 mg/L); the pH of the solution (4 and 10), and the TiO2 dosage (20 and 30 mg/L). The aqueous solution was subjected to constant circulation, inside the quartz tubes in order to carry out the experiments. The results showed that pH is the parameter with the greatest impact on degradation efficiency, which showed that at basic pH (10) a degradation rate of 99.91% was achieved, against 34.95% at acidic pH (4). It was concluded that the photo reactor using solar energy, presented itself as a strategic alternative for the removal of contaminants, including recalcitrant, such as synthetic dyes, which contribute to agro-industrial sustainability. [ABSTRACT FROM AUTHOR]

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The objective of this work was to study different treatments for the elimination of phenol compounds (PHE) and diethyl phthalate (DEP), comparing the efficiency of each treatment used individually and when mixed, to more complex matrices where these pollutants are in competition with each other. The treatment methods studied included adsorption with activated carbon (AC); advanced oxidation processes using UV-C/H2O2 and coupling (UV-C/H2O2/AC). The results obtained showed that the adsorption process using AC revealed that there was a greater elimination of the PHE pollutant in both synthetic effluent and tap water, with competition among the molecules. The results obtained in the UV-C/H2O2/AC coupling between the different activated carbons used in this study revealed that AC2 showed reduced efficiency in the removal of PHE. It showed a slower elimination rate when compared to AC1, which was justified by the properties of the AC, but the results showed a degradation rate higher than 90% in the two ACs used. The kinetic degradation constants of the micro-powder in the two matrices by AOP (UV-C/H2O2) and coupling (UV-C/H2O2/ AC1) in tap water effluent with DEP were all higher – ranging from 0.0673 to 0.1289 min–1 in comparison with synthetic multi-component laboratory effluent (DEP). The results of the kinetic curves allowed us to conclude that the AC adsorption process delays the elimination of the micropollutants understudy when compared with the other UV-C/H2O2 and UV-C/H2O2/AC processes, but it can be a positive material in the generation of efficient hydroxyl radicals in these treatment processes. [ABSTRACT FROM AUTHOR]

Summary: Rice is a staple food for a great part of the world's population, and its processing generates a great volume of low value by‐products, such as bran and broken grains. This work aimed to elaborate fermented rice by‐products extracts with probiotic strains and with different waxy maize starch (WMS) contents (0%, 4%, 8%, 12% and 16% w/w), in order to select one with texture profile similar to Greek‐style yogurt, and to characterise the chemical composition and sensory acceptance of the selected extract added with artificial strawberry aroma and fresh strawberry syrup. The texture profile of the extract changed with WMS content and the 4% WMS fermented rice by‐products extract was the most similar to Greek‐style yogurt. The flavoured fermented rice by‐products with WMS product presented 72.67% moisture, 2.55% protein, 0.2% lipid, 0.8% ash (340 mg 100 g−1 of potassium), 27.4 µmol Trolox g−1 and 134.74 mg GAE 100 g−1 of phenolic compounds. The flavoured fermented rice by‐products extract did not show microbiological risk and presented probiotic characteristic. Regarding the sensory analysis, it was observed that the aroma stood out among the other attributes, obtaining the highest score and acceptance index, while colour, flavour and texture scored 'liked regularly to moderately'. The flavoured fermented rice by‐products extract is an innovative product and feasible regarding the technological, physical, chemical, microbiological and sensory characteristics, having great potential to be inserted into the market. [ABSTRACT FROM AUTHOR]

In this study, the performance the treatment for the degradation of the pollutant diethyl phthalate (DEP) in synthetic effluent by the application of advanced oxidative process (AOP)-UV-C/H2O2 was verified. The study of oxidation kinetics followed a factorial design of eleven trials to understand the oxidation phenomena of DEP by AOP under experimental planning conditions. In this way, the influence of the H2O2 concentration, pH, temperature, and its effects were verified. The highest results were in the K9, K10 and K11 tests, which presented approximately 99.91; 96.18; 98.17% DEP degradation percentage (%), at pH 7, with 20 mM of H2O2 at 30°C in 120 min, respectively. For the DEP degradation percentage (%) there was a significant difference for pH with (p < 0.5) and the central points presented the results repeatability. Therefore, AOP as a treatment proposal for the degradation of DEP in agro-industrial effluent is efficient. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the efficiency of UV/H2 O2 /AC coupling processes and adsorbent behavior in coupling to eliminate phenol. Activated carbon was characterized for the textural analysis by isotherms of N2 adsorption and desorption at 77K, Scanning Electron Microscopy, infrared spectroscopy, elemental analysis, Boehm’s method and point of zero charge. Adsorption kinetics was performed for each 11 tests, according to the experimental design 23 + 3 central points, in which there were variations in pH, temperature and the quantity of activated carbon. The pseudo-second order model was the one that best represented the adsorption process. The best tests for H2 O2 /UV and H2 O2 /UV/AC processes were the central points with phenol elimination rates of 89% and 94%, respectively. The kinetic contribution of the hydroxyl radicals was calculated with the presence of tert-butanol showing that 78% of phenol elimination in the H2 O2 /UV/AC treatment was caused by their action. The H2 O2 /UV/AC coupling process is acceptable and presents a higher removal rate than the adsorption process with much shorter removal time. [ABSTRACT FROM AUTHOR]

Background. The use of natural plant antioxidants has been an alternative approach to synthetic antioxidants for food applications. This study investigated the antioxidant properties of the leaves of Curcuma longa L. against the oxidation of soybean oil using leaf extracts obtained from seven different types of organic solvents and compared to the action of efficient synthetic antioxidants which are widely used and low cost but with toxicity risk. The application of natural alternatives from sources still little studied is a proposal and the extraction of compounds with high antioxidant capacity may vary according to the type of solvent, its mixture, its polarity and other factors that burden or harm the health of the consumer. Materials and methods. The leaf extracts were sanitized, dried, and obtained for solvent selection. The quantification of total phenolic compounds (TPC) and antioxidants was performed by using different combinations and proportions of solvents: water (100%), ethanol (100%), methanol (100%), ethanol/water (70%:30%), methanol/water (70%:30%), methanol/acetic acid (99.5%:0.5%), and acetone/water/acetic acid (70%:28:2%). The solvent selected was the one that extracted the highest content of phenolic and antioxidant compounds (using the free radical DPPH scavenging method and FRAP assay). It used an accelerated storage test and experimental design to assess oxidative stability (using peroxide index (PI), thiobarbituric acid reactive substances (TBARS), dienes (DC) and triple conjugates (TC) and statistical analysis). Results. The ethanol/water solvent was efficient in the extraction of TPC (2422 mg GAE 100 g-1). The mixture of solvents extracted an average of 23.65% more TPC when compared to the single solvents. Regarding the antioxidant capacity, the ethanol/water solvent showed 1847 mg TE 100 g-1 using the DPPH and 217 µmol of FeSO4 100 g-1 using the FRAP assays. In addition, the oxidation of soybean oil was delayed by the accelerated storage test showing equivalent results to BHT at 0.02% for the values of PI, TBARS and DC/TC. Conclusion. The E/W extract showed the highest yield in the extraction of phenolic compounds and is a safe solvent for food. The addition of Curcuma longa L. leaf extract to soybean oil caused reductions in PI, TBARS, CD and CT values. The leaf extract of C. longa L. is considered to be a good alternative to synthetic antioxidants against the oxidative degradation of soybean oil. [ABSTRACT FROM AUTHOR]

Background. The diet of most of the population is limited to a reduced number of plants, even in areas that have a varied and extensive diversity, such as Brazil. Unconventional Food Plants (UFPs) are plants considered exotic, native, and wild that grow naturally and can be used as food. Among these is Talinum paniculatum (Jacq.) Gaertn., which is widespread throughout Brazil and can be a potential source of nutrients. Due to the potential of utilization of UFPs in human food and the lack of studies regarding the composition of T. paniculatum, this study aimed to assess the nutritional value of T. paniculatum leaves, their antioxidant capacity, and their antimicrobial activity for possible use in food. Materials and methods. The characterization of the leaves of T. paniculatum was carried out through analyses of proximal composition, color, ascorbic acid, mineral profile, and antinutritional factors showing the presence of condensed and hydrolysable tannins and nitrates in low concentrations. Solvents of water, ethanol, ethanol/water, methanol, methanol/water, methanol/acetic acid and acetone/water/acetic acid were used to evaluate the extraction yield of phenolic compounds, antioxidant capacity, and antibacterial activity of the extracts. Results. High contents of protein (18.61 g 100 g-1), insoluble dietary fiber (34.75 g 100 g-1), ascorbic acid (81.03 mg 100 g-1), magnesium, potassium, and calcium (649.600, 411.520 and 228.117 mg 100 g-1, respectively) were observed. Extraction using the mixture of solvents of methanol/acetic acid showed the highest yield of phenolic compounds (432.73 mg EAG 100 g-1) and antioxidant capacity using the DPPH assay (3144.92 mg 100 g-1). Bacillus cereus growth was inhibited by the T. paniculatum extracts. Conclusion. T. paniculatum leaves are a source of nutrients and their extracts have antioxidant and antibacterial potentials which can be used as supplements in food to improve one's health. [ABSTRACT FROM AUTHOR]