15 resultados para total solids

em Universidade Federal do Rio Grande do Norte(UFRN)


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Milk from different animals can be used for dairy production. Yoghurt is a popular fermented milk product and considered to be one of the greatest importance in terms of consumer acceptance and consumption. The present research deals with the production of strawberry set-type yoghurt by mixing goat and buffalo s milk and it has the objective of taking advantage of the intrinsic characteristics of each milk to produce a final product with desirable attributes. It was conducted by analyzing five experimental groups with different proportions of goat and buffalo s milk: C 100% goat s milk; 7C3B - 70% goat s milk and 30% buffalo s milk, 5C5B - 50% goat s milk and 50% buffalo s milk, 3C7B 30% goat s milk and 70% buffalo s milk; B - 100% buffalo s milk. Each group was evaluated for total solids content and the acidification profile was monitored every 30 minutes by pH analysis. The yoghurt samples were analyzed for physical-chemical (pH, acidity, protein, fat, total and reducing sugars, ash and total solids), rheological (syneresis and viscosity) and sensory characteristics (appearance, odor, consistency and flavour). Samples with higher percentual of bubaline milk reached Vm faster, but the time necessary for pH 4.6 (Te) were similar between groups. Statistical differences (p<0.05) were observed for fat and total solids content of yoghurt, with superior values for groups higher proportions of buffalo s milk. The parameters of behavior reached by the model of Ostwald of Waale pointed yoghurt samples as non-Newtonian and pseudoplastic fluids. Yoghurt made only with goat s milk (C) had higher values (p<0.05) for syneresis, which can be explained by its fragile coagulum. Additionally, this group also had the lowest sensory scores for the attributes consistence and taste, while bubaline yoghurt (B) obtained the best acceptance indexes for all of the appraised parameters

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This work targetet the caprine ice cream production added with probiotic bacteria Bifidobacterium animalis subsp. lactis. It is divided into two parts. In the first one, four caprine ice cream formulations were evaluated, in which it was used hydrogenated fat (F1 and F3) or fat substitute (F2 and F4) in two different flavors (F1 and F2, passion fruit, F3 and F4, guava). Statistical differences (p<0.05) were detected for their physical-chemical properties, mainly for total solids and fat, but no differences were observed for melting test results. When it went to sensory acceptance, all four ice cream formulations reached high acceptance indexes, mostly formulation F4, which was selected for further studies. In the second part, F4 formulation was prepared with the addition of probiotic bacteria Bifidobacterium animalis subsp. lactis. The growth kinetics was studied and it was observed that the cellular concentration peak was reached after four fermentation hours (10.14 log UFC/g). This time was selected for pre-fermentation procedure and posterior addition at ice cream syrup. In this part of the study, two experimental groups were evaluated: group G1, in which the probiotic addition occurred before the maturation step and group G2, which included a pre-fermentation step and probiotic addition after ice cream maturation. The physical-chemical properties of these two ice cream groups were similar, except for pH, which was higher for group G2 (p<0.05). G1 samples had superior melting rate (3.566 mL/min) and both groups presented microbiological and sanitary results in accordance to current Brazilian legislation. Also, G1 and G2 were considered sensory accepted due to their acceptance indexes higher than 70%. G1 and G2 sensory profiles were similar (p>0.05), and both ice cream samples exhibited high creaminess (6.76 to 6.91) and mouth melting sensation (6.53 to 6.67) scores, while low sandiness scores (0.85 to 0.86) were observed, positive characteristics for this kind of food product. During the first 24 hours after ice cream production, the population of B. animalis subsp. lactis decreased, reaching 7.15 e 6.92 log CFU/g for G1 and G2, respectively. Probiotic bacteria counts fluctuated in ice cream samples during the first 108 days at frozen storage, especially for G2 group. Decreased probiotic viability was observed for G1 samples during the first 35 days of frozen storage, mild variation between 35 and 63 days and stabilized counts were observed after this time. After 21 days at frozen storage, ice cream samples of G1 and G2 groups reached 1.2 x 109 and 1.3 x 109 CFU/portion, respectively. After 108 days under these storage conditions, the survival rate of B. animalis subsp. lactis was 94.26% and 81.10% for G1 and G2 samples, respectively. After simulation of gastroenteric conditions, G2 group reached 9.72 x 105 CFU/portion. Considering the current requirements of Brazilian legislation, which stipulates that functional foods must have minimum probiotic count between 108 and 109 CFU/portion and detectable probiotic bacteria after being submitted to gastroenteric conditions, it is concluded that the ice cream with the addition of Bifidobacterium animalis subsp. lactis made as shown in this work, can be considered as a dairy functional food

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In Natal still dominates the use of individual disposal systems for domestic sewage, once only 29% of the city has a sewarage system. Wastes that are accumulated in these individual treatment systems should be exhausted periodically, service provided by collector entrepreneurs. Some of these companies causing major damage to the environment. In Natal, only two companies have their own septage (RESTI) treatment system, which were designed with parameters from domestic sewage generating strain and inefficient systems. Therefore, the characterization becomes essential as a source of parameters for their design. Thus, this work presents the physical-chemical and microbiological characterization of waste pumped from individual sewage treatment systems. Samples collections were made weekly from 5 different trucks at the reception point on the treatment plant on the point of the preliminary treatment. From each truck it was taken 5 samples during the discharge in order to make a composite sample. Afterwards, samples were carried out to laboratory and analyses for determination of temperature, pH, conductivity, BOD, COD, nitrogen (ammonia e organic), alkalinity, oils, phosphorus, solids, faecal coliforms and helminth egg. The results were treated as a single database, and ranked according to its generating source (multi and single house, lodging, health, services and / or food), area of origin (metropolitan, south and north) and type of system (cesspits, septic tank and / or sink). Through these data it was possible to verify that the type of system adopted by most in Natal and the metropolitan region is cesspit, besides to confirm the difference between the septage of areas with a population have different social and economical characteristics. It was found that the septage have higher concentrations than domestic sewage, except for thermotolerant coliforms that showed concentrations of 1,38E+07. Among the parameters studied, is the median values identified for COD (3,549 mg / L), BOD (973mg / L) and total solids (3.557mg / L). The volatile fraction constitutes about 70% of the total solids of the septage. For helminths has been a median of 7 eggs/L. In general, the characteristics of the waste followed the variability found in the literature reviewed for all variables, showing high amplitudes

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The urban drainage is one of the powers of environmental sanitation and its scope is the quantitative and qualitative aspects. In decision making of managers and the engineering aspects of design are almost always taken into account only the quantitative aspects. However, the waters of the runoff have the highest concentrations of pollutants at the beginning of precipitation. Thus, if the plot pollution removed, the remaining portion can be used for other purposes. This work has aimed to present the variation of water quality of two drainage basins in the city of Natal / RN-Brazil to support the implementation of drainage to consider the qualitative aspect, and identify potential for the use of water. The basins (M and C) are analyzed closed-type, are in the urban area, are predominantly residential occupation and its waters are used for detention ponds and infiltration. The samples were divided into three phases, the first two direct to final points in a basin and the third in traps distributed over the surface drainage. The parameters had been analyzed were pH, conductivity, dissolved oxygen, Color, Turbidity, COD, Ammonia, nitrite, nitrate, total phosphorus, orthophosphate, Sediments solids, total solids, chloride, sulfate, alkalinity, calcium, magnesium, sodium, potassium, Heavy Metals (Chromium, Cadmium, Lead, Zinc and Copper), Eschichia coli and total coliforms. The parameters studied showed high initial pollution load, events and located in different proportions, except nitrite, heavy metals and biological indicators. The size of the surface drainage and topographic its features influence the quality of water. However, the form of sampling is crucial in the qualitative study in the basin. The samplers developed at work, were generated economic and representative results. The urban rainwater presents organic faecal indicators. The runoff of water from both basins shows no risk of salinity and sodicity for use in irrigation, should be noted the content of chloride in the choice of method of irrigation

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Urban growth of metropolitan areas has produced impacts of considerable importance on environment and water resources. Such impacts are in general associated with human activities, such as basin area uncontrolled development. In this context, Pitimbu river watershed, located at Natal metropolitan area, has been affected by uncontrolled development caused by urban expansion. Indeed, such effects have been reflected on water quantity and quality, which may produce social consequences. Pitimbu river is an important water supplier for human consumption, actually supplying a 2600 m3/h water discharge. This study aims to analyze the qualitative and quantitative aspects of water and sediment on Pitimbu river lowland portion. For this purpose, physical-chemical water properties were analyzed, and sediment macro invertebrates benthonic were monitored in two cross sections in a period between November 8th, 2007 and October 3rd, 2008. Monitoring methodology consisted of water and sediment sampling for laboratory analysis. Water quality analysis included Dissolved Oxygen, Oxygen Biochemical Demand, Nitrate, pH and Alkalinity, Suspended and Total Solids. The analysis of heavy metals in the sediment included Cadmium, Cobalt, Copper, Chrome, Silver and Nickel. Dry season water discharge data were measured and used to adjust recession function parameters, whose values reveal quick recession and strong river-aquifer unconfined interaction. Water quality analysis revealed the absence of degradation by organic composites. However, DO and BOD levels indicate that more consistent results could be provided if sampling time interval were reduced. Biomonitoring showed signs of aquatic ecosystem degradation by the absence of sensitive and abundance of resistant benthic organisms. Obtained results demonstrate the urgent need of effective management measures to provide environmental protection. The increase of environmental degradation will certainly make impracticable the use of water for human consumption

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Only 32% of the population of Natal is attended by sewage, while the remaining population use pits and septic tanks. The characterization of the contents of septic tanks and pits contributes to the performance of such system and may guide the decision on treatment of these contents. The main of this research is to characterize the contents of interior residential pits and septic tanks in the greater Natal, with the following specific goals: to develop and manufacture a sampler capable of collecting a representative sample of the entire column (the surface scum, the clarified liquid and sludge bottom); to compare the contents of the tanks with the pits; to compare the contents of the septage from vacuum trucks; to relate the composition content with socioeconomic characteristics of households; to compare the content in both chambers of the septic tanks in series; to assess the situation of the content before and six months after the cleanness; and ultimately propose a pilot scale plant for treatment of septage. Once the sampler was developed, samples were collected within 14 septic tanks and 10 pits in many districts of Natal. Medians of the 24 systems were obtained: temperature, pH, conductivity, oil and grease, total solids, total suspended solids and sediments of 28.0 °C, 6.95; 882 mS/cm, 75.2 mg/L; 10,169 mg/L, 6,509 mg/L and 175 mL/L respectively; 111.0 mgN/L for ammonia, 130.5 mgN/ L for organic nitrogen, 0.2 mgN/L for nitrite, 0.4 mg/L for nitrate; 8935 mgO2/L for COD, 29.2 mgP/L for total phosphorus, thermotolerant coliforms from 9.95 E +06 CFU/100mL helminth eggs and 9.2 eggs/L with a maximum concentration of 688 eggs/L and minimum of 0 eggs/L. Medians of organic nitrogen and TKN were significantly different between groups of tanks and pits. The systems with cleanness gap from 11 and 20 years presented the higher concentrations for most variables. The effluent from the toilets and bathrooms participate more effectively in contributing fractions of solids, alkalinity, nitrogen, COD, total phosphorus, thermotolerant coliforms and helminth eggs. The systems used by socioeconomics class with income from R$ 3,700.00 to R$ 7,600.00, presented higher concentrations for COD, nitrogen, solids and helminth eggs. The first of the two chambers had always presented higher concentrations over the second compartment. The analysis of variance for most variables, showed that the values of septic tanks, pits and septage from vacuum trucks belong to the same group. In the samples taken after cleanness, the median of pH and temperature increased, while alkalinity, COD, organic nitrogen, total phosphorus, ammonia and helminth eggs decreased. The oils and greases and thermotolerant coliforms had slightly varied due to the continuous release of sewage into the systems that maintained their steady state concentrations.

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The detention and infiltration ponds of urban drainage system has function to protect the population from undesirable effects of floods. In general these ponds are not completly used and it potential is wasted. As it are disseminated at different places at cities it can reduce costs with water transport and permit water preservation of best quality. Some it utilities includes use in green areas irrigation, industrial among than cooling towers and boiler, soil compaction, cleaning urban road, pisciculture and fire fighting system. The quality these water is influenced by anauthorized sewage in the drainage system. This study was performed in six detention and infiltration ponds at drainage system of Natal, which aim was to verify the non-portable use these ponds on urban environment. As indirect aim would to incentive the water utilization these ponds as a water source to another uses in urban environment. These ponds represents the characteristics of detention and infiltration of Natal city and consequently of Brazil. As the water quality, the ponds presents following characteristics: three has apparently good quality, other showed intermediate condition and two had water polluted. Were performed twenty sample in each ponds and the following parameters assessed: pH, temperature, dissolved oxygen, turbidity, electrical conductivity, coliform thermotolerant, ammonia, organic nitrogen, TKN, nitrate, total phosphorus and alkalinity, bicarbonate, chloride, total hardness, calcium and magnesium hardness, total solids, TSS, TDS, COD and SAR°. To utilization on pisciculture we recommend use in ponds which presents the best quality. Only one pond presented higher pollutants and it not being appropriated for use in cooling tower. The content of solids suspension restricted the water use in all ponds in boilers. As water use in soil compaction, cleaning urban road and fire fighting system the water from these ponds are not appropriated. However, the recommended limits from literature are to domestic sewage, due to this, the parameters are restrictive to diminish the sanitary risk that could be offered with it utilization. The infiltration velocity of water these assessed ponds restrict a moderato use, however the effects are potentiated only in soil less sandy, which not occur in Natal. It is recommend the unrestricted irrigation utilization in ponds with best quality of water, and a restricted irrigation to ponds with worst quality of water. As load of pollutants, it is recommended a complementary treatment in those ponds whit higher load to diminish sanitary risks. In only one pond was found one helminth eggs and due to the convention formula of results, it was found for all ponds less than 1 helminth/liter eggs.

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The direct relationship with the processing, industrial yield and price of milk, the importance of the centesimal composition of milk and their protein fractions has increased for both the dairy industry and for the producers, so it is important to identify the possible causes on variation of these components. The aim of this study was to evaluate the effect of the seasons, order of calving and lactation phase on milk composition and protein fractions in dairy farms in the Agreste and Leste meso-regions, of Rio Grande do Norte State (RN). Milk samples were taken in seven milk farms directly from the bulk tanks except for one farm where samples were taken from higher milking cows producers and heifers. The experiment was done in seven properties with milk samples taken directly from the bulk tanks and in one property were collected from higher production cows and heifers. Composition analyses were carried out for both experiments and sensorial trial was performed for the second experiment only. The data results were submitted to analysis of variance (ANOVA) and Tukey test performed for 5% significance level. In the first experiment was observed response of the seasons, dry and rainy season; while in the second, the effect of the order of calving and lactation phase had influence on milk composition and protein fractions. There was significant response (p < 0.05) for season effects but due to farms. The rainy season had higher averages in the protein, lactose, total solids and nonfat dry extract. Multiparous cows had higher CCS, NUL and PCAS milk contents; while, first calving heifers showed higher average for the sensory attribute, color of milk. The final third of lactation was responsible for the elevation of the levels of almost all milk components and their protein fractions

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Goats are social animals which groups are organized from dominance hierarchies, established by agonistic behaviors. The quality and productivity of the goat s milk can be influenced by the dominance hierarchy. In this context, the objectives of our work were describe the social and food behavior of Saanen goats in a semi-extensive production system; characterize the social organization from the assessment of dominance hierarchies in two seasonal periods and correlate the physicochemical quality of the goats milk according hierarchical position. The experiment was conducted in the EMPARN s experimental station, located in the district of Cruzeta/RN. We utilized 17 multiparous goats of the Saanen race, with different age and weight. The observations were performed in precipitation and drought phases. The scan method recorded the trough permanence and agonistic interactions by method "all occurrences" in the pasture the alimentary behaviors of eat, ruminate on foot, ruminate lying, leisure on foot, leisure lying and walk, by the focal animal sampling method. The goats milk was submitted to analyzes of: density, protein, fat, lactose, CSS and total solids. The animals spend most of the time feeding themselves, and the activities that demand greater energy expenditure are done in the morning. The animals changed the hierarchical structure during the seasonal periods because of the withdrawal of some individuals of the group, having more aggressive behavior in the rainy season. The dominant animal the lowet production, the more CSS and the lesser fat, the goat in the middle of the hierarchy was the one that obtained the best production and quality. We conclude that the Saanen goats adapt to the environment and the conditions of the group to ensure better survival and its production is influenced by the internal dynamics of the group

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The aim of this study was to evaluate the potential of near-infrared reflectance spectroscopy (NIRS) as a rapid and non-destructive method to determine the soluble solid content (SSC), pH and titratable acidity of intact plums. Samples of plum with a total solids content ranging from 5.7 to 15%, pH from 2.72 to 3.84 and titratable acidity from 0.88 a 3.6% were collected from supermarkets in Natal-Brazil, and NIR spectra were acquired in the 714 2500 nm range. A comparison of several multivariate calibration techniques with respect to several pre-processing data and variable selection algorithms, such as interval Partial Least Squares (iPLS), genetic algorithm (GA), successive projections algorithm (SPA) and ordered predictors selection (OPS), was performed. Validation models for SSC, pH and titratable acidity had a coefficient of correlation (R) of 0.95 0.90 and 0.80, as well as a root mean square error of prediction (RMSEP) of 0.45ºBrix, 0.07 and 0.40%, respectively. From these results, it can be concluded that NIR spectroscopy can be used as a non-destructive alternative for measuring the SSC, pH and titratable acidity in plums

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The pulps are products that add economic value enjoy the fruits of the surplus productions of the same. Have good market acceptance because of its practicality and diversity of flavors available year round. In order to assess the quality of the fruit pulp through the physical and chemical parameters and the characteristics of manufacturing industry, we analyzed 36 samples of frozen fruit pulp of three brands marketed in RIO Grande do Norte, 14 brand A, 12 of 10 brand B and brand C, which corresponded to 14 different flavors, of which 10 have identity Standards and Quality (ISQ S) established by the Ministério da Agricultura, Pecuária e Abastecimento (MAPA), totaling 27 samples with ISQ s. We conducted the following physicalchemical analyzes on samples of fruit pulp: Total solids, total soluble solids, pH, titratable acidity, total sugars and the determination of ascorbic acid. The percentage of failure for each parameter evaluated was 37, 04% in total soluble solids, 22,22% for total solids and titratable acidity, 7,40% in relation to pH. The total sugars were within the requirements demanded by the MAPA and ascorbic acid content, determined only in the pulp of acerola and cashew, presented a non compliance in the pulp of brand B. The percentage of failures of the pulps with ISQ S was 59% with brand A, B and C accounted for 3,70%, 33,33% and 22,22% respectively. The pulps which have no established atandards such as pineapple pulp, showed similar values between brands and literature data unlike the pulp of plum, jackfruit and tamarind which diverged greatly in parameters such as total solids and total soluble solids. The study demonstrates the need for greater quality control by the producers with respect to raw materials, processing, packing, stored and the importance of ISQ S to establish the flavors have not yet covered by existing legislation, but already highly commercialized

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The objective of this research was to evaluate the influence of the supply of five types of native and exotic cacti Brazilian semiarid northeast on the sensory characteristics of milk of Saanen goats. Five multiparous goats were used with nine weeks of lactation, average live weight of 50 kg ± 4 kg., confined and distributed in a Latin square design 5 x 5 with five experimental diets and five periods. Each period lasted 17 days, with 10 days of adaptation to the diets of the animals and seven days for the data collection. The treatments were defined based on dry matter consisted of: 47.33 to 50.12% of a cactus (“Xiquexique”, “Mandacaru”, “Facheiro” or two species of forage cactus “Miúda” or “Orelha de Elefante Mexicana”) more 18.78 to 19.79% hay of plant “Sabiá” and 31.10 to 32.89% of concentrate. There was not effect of the experimental diets in the physical and chemical composition of milk for fat, total solids and salts, which showed mean values of 3.24%; 11.30% and 0.66%, respectively. However the protein, lactose, nonfat dry extract and freezing point were affected by diets. In the profile of fatty acids was higher concentration of fatty short and medium chain fatty acids, however, there were not changes between treatments, except for the butyric acid (C4:0), with mean values of 4.24% (“Orelha de Elefante Mexicana”) to 6.05% (“Facheiro”). The diets also did not provide sensory changes in milk for the parameters: odor, flavor, aftertaste and overall assessment. The use of the five cactus in the diet of dairy goats do not influence the sensory characteristics and lipid profile of milk. The physical and chemical composition of milk was showed within the minimum requirements of current legislation, except for nonfat dry extract and freezing point.

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This work evaluated the fresh, spray dried (with 10 % of Arabic Gum) and freeze dried jambolan pulp (Eugenia jambolana Lam.) in regard to physicochemical (pH, moisture, water activity, average particle diameter, solubility and color), bioactive [total phenolic content (TPC), monomeric anthocyanin, pronathocyanidin (PA), total elagic acid (TEA), myricetin and cyanidin] and in vitro functionality (antioxidant, antienzymatic and antimicrobial activities]. In addition, the in vivo functionality of jambolan pulp was investigated using the Caenorhabditis elegans model for insulin signaling, longevity and induced neurodegeneration (Alzheimer’s disease and Parkinson’s disease related symptoms). The dried jambolan pulp presented TPC retention (50% to 75%), PA (90% to 98%), TEA (31% to 83%), myricetin (40% to 84%), cyanidin (72% to 84%) and antioxidant activity (15%). The fresh jambolan pulp, the freeze dried pulp and the spray dried jambolan pulp presented high enzymatic inhibitory activity against pancreatic lipase (4,4 to 5,8 mg/mL), alpha-glycosidase (10,3 to 13,8 mg/mL) and alpha-amylase (8,9 to 11,2 mg/mL). They also were active inhibitors against the pathogen S. aureus. The dried jambolan experimental samples were able to increase the expression of several genes linked to the insulin signaling pathways (SIR-2.1, PPTR-1, DAF-16, SOD-3, e CTL) and increased the lifespan in C. elegans (18,07 % - 24,34 %), besides decreasing the amyloid AB1-42 aggregation induced paralysis and MPP+ (1-methyl-4-phenylpyridinium) induced neurodegeneration. Based on that, the jambolan pulp and the spray dried jambolan pulp were further selected for the production of caprine frozen yogurt with the addition of Bifidobacterium animalis subsp. lactis BI-07. The final product were evaluated in regard to their physicochemical (pH, acidity, total solids, protein, total reducing sugars, fat, ashes, overrun, melting test), bioactive (TPC and monomeric anthocyanin, antioxidant activity, probiotic viability and sensory analysis (sensory acceptance). The results showed that samples with probiotic had lowest pH and higher acidity, TPC, anthocyanin and antioxidant activity. It was also observed low overrun (14.2% to 22.6%). vi Samples with probiotic had lower flavor scores. Overall, this research presents the jambolan as a highly functional bioactive-rich fruit with the potential to modulate important biological pathways, extend lifespan and retard the development of neurodegenerative diseases. Jambolan is an underexploited exotic fruit with a high colorant potential and this thesis shows for the first time in the literature important technological, biological and scientific data about this fruit that could be used towards the development of health-oriented food products.

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This work was performing effluent degradation studies by electrochemical treatment. The electrochemical oxidation (EO) hydroquinone (H2Q) was carried out in acid medium, using PbO2 electrode by galvanostatic electrolysis, applying current densities of 10 and 30 mA/cm2 . The concentration of H2Q was monitored by differential pulse voltammetry (DPV). The experimental results showed that the galvanostatic electrolysis process performance significantly depends on the applied current density, achieving removal efficiencies of 100% and 80 % and 10 applying 30 mA/cm2 , respectively. Furthermore, the electroanalytical technique was effective in H2Q be used as a detection method. In order to test the efficiency of PbO2 electrode, the electrochemical treatment was conducted in an actual effluent, leachate from a landfill. The liquid waste leachate (600ml effluent) was treated in a batch electrochemical cell, with or without addition of NaCl by applying 7 mA/cm2 . The efficiency of EO was assessed against the removal of thermo-tolerant coliforms, total organic carbon (TOC), total phosphorus and metals (copper, cobalt, chromium, iron and nickel). These results showed that efficient removal of coliforms was obtained (100%), and was further decrease the concentration of heavy metals by the cathode processes. However, results were not satisfactory TOC, achieving low total removal of dissolved organic load. Because it is considered an effluent complex were developed other tests with this effluent to monitor a larger number of decontamination parameters (Turbidity, Total Solids, Color, Conductivity, Total Organic Carbon (TOC) and metals (barium, chromium, lithium, manganese and Zinc), comparing the efficiency of this type of electrochemical treatment (EO or electrocoagulation) using a flow cell. In this assay was compared to electro streaming. In the case of the OE, Ti/IrO2-TaO5 was used as the anode, however, the electrocoagulation process, aluminum electrodes were used; applying current densities of 10, 20 and 30 mA/cm2 in the presence and absence of NaCl as an electrolyte. The results showed that EO using Ti/IrO2–TaO5 was anode as efficient when Cl- was present in the effluent. In contrast, the electrocoagulation flow reduces the dissolved organic matter in the effluent, under certain experimental conditions.

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The unstable non acid milk (UNAM) is characterized by coagulation in the alcohol test and wanted acidity (14-18°D). Among Brazilian regions, the South and Southeast have the highest occurrence of LINA, which has been causing problems for both producers and for industries, due to the disposal or undervaluation of milk. In the Northeast there are few studies that indicate their occurrence and quality. The objective of this study was to identify the occurrence of unstable non-acid milk in the west and central mesoregions of Rio Grande do Norte, determine their physicochemical characteristics, test alcoholic graduations and evaluate their correlation with the quality of milk. 176 raw milk samples were analyzed in the period from September to December /2014 from 23 APASA’s cooling tanks, located in 7 cities of west and central mesoregions RN. The samples were collected in duplicate, one sample used for alcohol testing at 68, 72 and 76%, measurement of pH, acidity, electrical conductivity and boiling proof, made in LABOLEITE / UFRN; and the other sample containing Bronopol® preservative, was sent to the APCBRH (Cattle Breeders Association Paranaense Holstein) laboratory in Curitiba-PR, which were analyzed fat, protein, total solids, lactose, casein, urea nitrogen and somatic cell count. The test alcohol samples disapproved 31.82%, of which 30% proved to be non-acid, and 30% had high acidity. The samples were divided into three classes: Stable Milk, UNAM and acid milk. 3% Tukey test was used for comparison of stable milk components and UNAM and there was no significant difference between them. Both classes obtained averages within the standard required by IN 62. The average value of electric conductivity was 4.84 mS/cm for stable milk, 4.55 mS/cm for unstable and acid milk and 4.53 mS/cm for non-acid unstable milk. The electrical conductivity was positively correlated with alcohol stability of milk and negative correlation with acidity and pH. Could not observe direct relationship between the electrical conductivity and the somatic cell count.The boiling test was negative for all samples UNAM. It can be concluded that the incidence of UNAM in the studied region is low, although the predisposing factors such as heat stress, drought and nutritional deficiency. In conclusion, the UNAM has quality similar to stable milk, conform the norms required by Agriculture Ministry, and with adequate thermal stability, which proves that there is no reason to reject this milk by industry.