Optimization of indirect wastewater characterization using led spectrophotometry: a comparative analysis of regression, scaling, and dimensionality reduction methods.

LED spectrophotometry is a robust technique for the indirect characterization of wastewater pollutant load through correlation modeling. To tackle this issue, a dataset with 1300 samples was collected, from both raw and treated wastewater from 45 wastewater treatment plants in Spain and Chile collected over 4 years. The type of regressor, scaling, and dimensionality reduction technique and nature of the data play crucial roles in the performance of the processing pipeline. Eighty-four pipelines were tested through exhaustive experimentation resulting from the combination of 7 regression techniques, 3 scaling methods, and 4 possible dimensional reductions. Those combinations were tested on the prediction of chemical oxygen demand (COD) and total suspended solids (TSS). Each pipeline underwent a tenfold cross-validation on 15 sub-datasets derived from the original dataset, accounting for variations in plants and wastewater types. The results point to the normalization of the data followed by a conversion through the PCA to finally apply a Random Forest Regressor as the combination which stood out These results highlight the importance of modeling strategies in wastewater management using techniques such as LED spectrophotometry.

Diurnal High Temperatures Affect the Physiological Performance and Fruit Quality of Highbush Blueberry (Vaccinium corymbosum L.) cv. Legacy.

In this study, the physiological performance and fruit quality responses of the highbush blueberry (Vaccinium corymbosum) cultivar Legacy to high temperatures (HTs) were evaluated in a field experiment. Three-year-old V. corymbosum plants were exposed to two temperature treatments between fruit load set and harvest during the 2022/2023 season: (i) ambient temperature (AT) and (ii) high temperature (HT) (5 °C ± 1 °C above ambient temperature). A chamber covered with transparent polyethylene (100 µm thick) was used to apply the HT treatment. In our study, the diurnal temperature was maintained with a difference of 5.03 °C ± 0.12 °C between the AT and HT treatments. Our findings indicated that HT significantly decreased CO2 assimilation (Pn) by 45% and stomatal conductance (gs) by 35.2% compared to the AT treatment. By contrast, the intercellular CO2 concentration (Ci) showed higher levels (about 6%) in HT plants than in AT plants. Fruit quality analyses revealed that the fruit weight and equatorial diameter decreased by 39% and 13%, respectively, in the HT treatment compared to the AT treatment. By contrast, the firmness and total soluble solids (TSS) were higher in the HT treatment than in the AT treatment. Meanwhile, the titratable acidity showed no changes between temperature treatments. In our study, Pn reduction could be associated with stomatal and non-stomatal limitations under HT treatment. Although these findings improve our understanding of the impact of HTs on fruit growth and quality in V. corymbosum, further biochemical and molecular studies are need.

Effect of a lime-based bedding conditioner on physical-chemical characteristics and microbiological counts of recycled manure solids.

Bedding materials are aimed at providing a safe and comfortable resting environment for cows. Control of pathogen proliferation in these substrates is crucial to prevent intramammary infections in dairy cows, as these can significantly impact milk quality, cow health, and farm productivity. This is particularly relevant in the case of organic bedding substrates, including manure-derived materials. This study aimed to evaluate the in vitro effect of a lime-based conditioner (LBC), composed of CaCO3MgCO3 and Ca(OH) 2 * Mg(OH)2, at increasing concentrations on the physical-chemical characteristics and bacterial counts of untreated anaerobically digested manure solids (ADMS) and separated raw manure solids (SRMS). Unused ADMS and SRMS were evaluated at four LBC weight-based concentrations: 0 (as untreated control), 10, 15, and 20% of LBC inclusion. The bedding materials were assessed immediately after LBC addition (0 h) and after 24, 72, and 168 h of storage at 28°C. The dry matter content (DM), and pH were measured for all the time points. Standard microbiological methods were used to assess total bacterial counts (TBC), other Gram-negative bacteria, coliforms, Escherichia coli, and streptococci and streptococci-like organism (SSLO). It was observed a linear increase in both DM and pH with increasing concentrations of LBC. Specifically, for each percentage unit increase of LBC, the DM of ADMS and SRMS increased by 0.73 and 0.71%, respectively. Similarly, for each percentage unit of LBC, the pH of ADMS and SRMS increased by 0.15 and 0.19, respectively. Conversely, a linear decrease in TBC, Gram-negative bacteria, coliforms, E. coli, and SSLO was observed with increasing concentrations of the LBC. Manure-derived materials without the inclusion of the LBC had bacterial counts that tended to remain high or increase over time. Otherwise, bedding materials with LBC application had reduced bacterial counts. Based on the results of the present study, it was observed that the higher the concentration of LBC, the more significant the reduction of bacterial counts. Specifically, bacterial recovery was lower when higher concentrations of LBC were applied. Our findings underscore the potential of LBC in effectively controlling environmental bacteria and improving the physical-chemical characteristics of manure-derived bedding materials to improve cow health and welfare.

Characterization of sugarcane bagasse solubilization and utilization by thermophilic cellulolytic and saccharolytic bacteria at increasing solid loadings.

In Brazil the main feedstock used for ethanol production is sugarcane juice, resulting in large amounts of bagasse. Bagasse has high potential for cellulosic ethanol production, and consolidated bioprocessing (CBP) has potential for lowering costs. However, economic feasibility requires bioprocessing at high solids loadings, entailing engineering and biological challenges. This study aims to document and characterize carbohydrate solubilization and utilization by defined cocultures of Clostridium thermocellum and Thermoanaerobacterium thermosaccharolyticum at increasing loadings of sugarcane bagasse. Results show that fractional carbohydrate solubilization decreases as solids loading increases from 10 g/L to 80 g/L. Cocultures enhance solubilization and carbohydrate utilization compared to monocultures, irrespective of initial solids loading. Rinsing bagasse before fermentation slightly decreases solubilization. Experiments studying inhibitory effects using spent media and dilution of broth show that negative effects are temporary or reversible. These findings highlight the potential of converting sugarcane bagasse via CBP, pointing out performance limitations that must be addressed.

Metabolic and productive parameters of lactating dairy cows under heat stress conditions supplemented with plant polyphenol extract.

The impact of heat stress on dairy cattle leads to significant economic losses and a negative impact on the welfare of the animals. The objective of this research was to evaluate the effect of the nutritional additive (Thermoplus®) in dairy cows under postpartum heat stress conditions, and its effects on the metabolic profile, production and quality of milk. Eighteen lactating Holstein cows (8 multiparous and ten primiparous), in a free-stall system, with a mean body condition score (BCS) of 3.14 ± 0.05, live weight of 624.55 ± 18, 61 kg, with initial mean days in milk (DIM) of 90 ± 10.11, were selected. The animals were grouped into a control (CG, n = 9) and a treatment (TG, n = 9). Both groups underwent 14 days of diet adaptation, the TG received the basal diet supplemented with 50 g of the additive, once a day, individually, while the control group received only the total diet. Data collection of metabolic and productive parameters were evaluated on days -14 (before adaptation), 1 (after the diet adaptation period), 16, 30, and 44. Milk, blood, and body condition score (BCS) were collected once a day, and heart rate, respiratory rate, and rectal temperature were collected twice a day. Serum concentrations of albumin, calcium, magnesium, glucose, gamma-glutamyl transferase (GGT), beta-hydroxybutyrate (BHBA), non-esterified fatty acids (NEFAs), and paraoxonase-1 (PON-1) were evaluated. In the milk, the percentage of fat, protein, lactose, and total solids were determined in each sampling. Milk yield was measured daily. Humidity and ambient temperature values were collected on the days of the collection every 30 min, from 5:30 am to 5:00 pm, to calculate the temperature-humidity index (THI). Statistical analyzes were performed using the SAS software (version 9.3, SAS Institute Inc., Cary, NC, USA). The THI ranged from 62.22 to 79.47. Our findings showed that when the THI was greater than 72, the animals in the TG were able to maintain milk yield (Odds ratio (OD) = -0.0577,), and the animals in the CG had a greater chance of reducing it (OD = -0.2301). Multiparous cows in the TG had higher milk yield than CG (32.57 ± 0.34 vs 30.50 ± 0.36 kg per day; P = 0.0078) and lower SCC (34.110 ± 6,940 vs 665.50 ± 214.41 cells per ml; P = 0.03), with the same percentages of total solids (P > 0.05). In multiparous metabolic markers, TG when compared CG had higher albumin concentrations (2.50 ± 0.07 vs 2.12 ± 0.07 g/dl; < 0.001), equal PON-1 (P > 0.05), and higher BHBA levels (0.49 ± 0.03 vs 0.39 ± 0.04 mmol/l). Primiparous from the CG had higher concentrations of NEFA (0.18 ± 0.02 mmol/l) than multiparous from the same group (0.09 ± 0.02 mmol/l) P = 0.0265. The use of the plant polyphenol extract in postpartum Holstein cows challenged by heat stress had beneficial effects on the production and health of the mammary gland in multiparous cows without decreasing milk solids. The non-reduction of the activities of the acute phase proteins indicates an immunomodulatory and inflammatory-reducing effect of the product used.

Pre-Harvest Salicylic Acid Application Affects Fruit Quality and Yield under Deficit Irrigation in Aristotelia chilensis (Mol.) Plants.

Salicylic acid (SA) application is a promising agronomic tool. However, studies under field conditions are required, to confirm the potential benefits of SA. Thus, SA application was evaluated under field conditions for its effect on abscisic acid levels, antioxidant related-parameters, fruit quality, and yield in Aristotelia chilensis subjected to different levels of irrigation. During two growing seasons, three-year-old plants under field conditions were subjected to full irrigation (FI: 100% of reference evapotranspiration (ETo), and deficit irrigation (DI: 60% ETo). During each growth season, a single application of 0.5 mM SA was performed at fruit color change by spraying fruits and leaves of both irrigation treatments. The results showed that DI plants experienced moderate water stress (-1.3 MPa), which increased ABA levels and oxidative stress in the leaves. The SA application facilitated the recovery of all physiological parameters under the DI condition, increasing fruit fresh weight by 44%, with a 27% increase in fruit dry weight, a 1 mm increase in equatorial diameter, a 27% improvement in yield per plant and a 27% increase in total yield, with lesser oxidative stress and tissue ABA levels in leaves. Also, SA application significantly increased (by about 10%) the values of fruit trait variables such as soluble solids, total phenols, and antioxidant activity, with the exceptions of titratable acidity and total anthocyanins, which did not vary. The results demonstrated that SA application might be used as an agronomic strategy to improve fruit yield and quality, representing a saving of 40% regarding water use.

Seasonal quality of milk from Creole grazing goats, stabled Saanen and French-Alpine goats / Calidad estacional de leche de cabras Criollas en pastoreo vs cabras estabuladas Saanen y Alpina-Francesa / Qualidade sazonal do leite de cabras Crioulas em pastagem vs cabras estábuladas Saanen e Franco-alpina

Abstract Background: Goat milk production has been increasing in northern Mexico; however, there is little information available about its quality. Objective: To compare goat milk quality during three seasons among creole goats in a traditional grazing system and stabled Saanen and French-Alpine goats. Methods: An experiment was performed in a completely randomized nested design with seasonality factor (fixed effects) with three levels (rain, transition, and drought) and breed factor (fixed effect with three levels (Creole, Saanen and French-Alpine)) nested within the season-of-the-year factor. Fifteen goats were randomly selected: five Creole in the extensive grazing system, five stabled Saanen, and five stabled French-Alpine. The factors assessed in milk were fat content, non-fat solids, protein, lactose, salts, density, freezing point, conductivity, and pH (using a Lactoscan® device). Results: With respect to season for all the breeds: fat, non-fat solids, protein, lactose, and salt contents were higher (p≤0.05) for goats sampled in the rainy season, followed by drought and transition seasons, respectively. The variables related to milk quality by breed and season showed that milk fat content of creole goats was greater (p≤0.05) in the drought season; salt and non-fat content (p≤0.05) in the three seasons of the year; density and protein increased (p≤0.05) in the transition and rainy seasons, while lactose was greater (p≤0.05) in drought and rainy seasons; protein was greater (p≤0.05) in transition and rainy seasons; and the freezing point was lower (p≤0.05) in the transition season. Regarding conductivity, French-Alpine milk was greater (p≤0.05) in the drought season. Conclusion: Season of the year significantly affects milk quality, with increased quality during the rainy season in creole grazing goats.

Resumen Antecedentes: La producción de leche de cabra se ha venido incrementando en el norte de México,; sin embargo, existe poca información sobre su calidad. Objetivo: Comparar la calidad de la leche de cabra durante tres épocas del año para cabras criollas en pastoreo y cabras puras de dos razas diferentes bajo estabulación. Métodos: El experimento se realizó mediante un diseño anidado completamente aleatorizado, con el factor época del año (efecto fijo) con tres niveles (lluvia, transición y sequia) y el factor raza (efecto fijo) con tres niveles (Criolla, Saanen y Alpino-Francesa) anidado dentro del factor época del año. En el sistema de pastoreo extensivo se eligieron al azar cinco cabras de raza Criolla, en el sistema estabulado se eligieron al azar cinco cabras de la raza Saanen y cinco de la raza Alpino-Francesa. La variables medidas fueron: contenido de grasa, sólidos no grasos, proteína, lactosa, sales, densidad, punto de congelación, conductividad y pH (utilizando el dispositivo Lactoscan®). Resultados: Respecto a la temporada del año para las tres razas se encontró que los contenidos en leche de grasa, sólidos no grasos, proteína, lactosa y sales fueron mayores (p≤0,05) en la época de lluvias, seguido por la leche muestreada en sequía y transición. Las variables por raza y temporada del año arrojaron que la grasa fue mayor (p≤0,05) en cabras criollas en sequía, solidos no grasos fue mayor (p≤0,05) en las tres temporadas del año en cabras criollas, la densidad aumentó (p≤0,05) en cabras criollas en transición y lluvia. La proteína fue mayor (p≤0,05) en cabras criollas en transición y lluvia, mientras que la lactosa fue mayor (p≤0,05) en cabras criollas en sequía y lluvia. El menor punto de congelación (p≤0,05) se presentó en cabras criollas en transición, la conductividad fue mayor (p≤0,05) en cabras Alpina-Francesa en sequía y la concentración de sales fue mayor (p ≤0,05) en cabras criollas durante las tres temporadas. Conclusión: Existe un marcado efecto de la temporada sobre la calidad de la leche, siendo la epoca de lluvias cuando se presenta mejor calidad en cabras criollas en pastoreo.

Resumo Antecedentes: No norte do México a produção de leite de cabra aumentou; no entanto, a qualidade do leite é desconhecida. Objetivo: Comparar a qualidade do leite de cabra durante três estações do ano com cabras crioulas em sistema de pastoreio tradicional e cabras Saanen e franco-alpinas em estábulos. Métodos: O experimento foi realizado através de um delineamento completamente casualizado com o fator de sazonalidade (efeitos fixos) com três níveis (chuva, transição e seca) e fator de raça (efeito fixo com três níveis (crioulo, Saanen e franco-alpino) aninhados dentro do fator estação do ano quinze cabras foram selecionadas aleatoriamente, cinco no sistema de pastejo extensivo, cinco Saanen e cinco Franco-Alpino no sistema estábulo. Os fatores avaliados no leite foram teor de gordura, sólidos desengordurados, proteína, lactose, sais, densidade, ponto de congelamento, condutividade e pH pelo aparelho Lactoscan®. Resultados: Em relação às estações do ano, nas três raças, mostrou que os teores de gordura, sólidos desengordurados, proteínas, lactose e sal foram maiores (p≤0,05) nas cabras cujo leite foi amostrado na ocasião um de chuvas seguido por aquele amostrado nas estações de seca e transição, respectivamente. As variáveis relacionadas à qualidade do leite de cabra por raça e ano, mostraram que nas cabras crioulas o teor de gordura foi maior (p≤0,05) na estação seca; teor de sal e gordura (p≤0,05) nas três estações do ano; a densidade aumentou significativamente e o teor de proteína foi maior (p≤0,05) nas estações de transição e chuvas, enquanto o valor de lactose foi maior (p≤0,05) nas estações seca e chuvosa; o teor de proteína foi maior (p≤0,05) nas estações de transição e chuvas; e o ponto de congelamento foi menor (p≤0,05) na estação de transição. Em relação à condutividade, o leite de cabra franco-alpino apresentou valor significativamente superior (p≤0,05) na seca. Conclusão: A qualidade do leite tem um efeito significativo por estação, sendo que a estação chuvosa aumentou a qualidade do leite em cabras crioulas em pastejo.

Effects of solid retention time and exposure mode to electric current on Remazol Brilliant Violet removal in an electro-membrane bioreactor.

The performance of an electrochemically assisted anoxic-oxic membrane bioreactor (A/O-eMBR) was assessed as an alternative for azo dye (Remazol Brilhant Violet (RBV)) removal from simulated textile wastewater. The A/O-eMBR was operated under three experimental conditions (runs I, II, and III), in which different solids retention time (SRT) (45 and 20 d) and exposure mode to electric current (6'ON/30'OFF and 6'ON/12'OFF) were assessed. The reactor exhibited excellent decolorization performance for all runs, with average dye removal efficiency ranging from 94.3 to 98.2%. Activity batch assays showed that the dye removal rate (DRR) decreased from 16.8 to 10.2 mg RBV L-1 h-1 when the SRT was reduced from 45 to 20 d, likely attributed to the lower biomass content under lower sludge age. At the electric current exposure mode of 6' ON/12'OFF, a more substantial decrease of DRR to 1.5 mg RBV L-1 h-1 was noticed, suggesting a possible inhibitory effect on dye removal via biodegradation. By reducing the SRT to 20 d, a worse mixed liquor filterability condition was observed, with a membrane fouling rate (MFR) of 0.979 kPa d-1. In contrast, using the electric current exposure mode of 6'ON/12'OFF resulted in lower membrane fouling propensity, with an MFR of 0.333 kPa d-1. A more attractive cost-benefit ratio for dye removal was obtained using the exposure mode of 6'ON/30'OFF, for which the energy demand was estimated at 21.9-22.6 kWh kg dye-1 removed, almost two times lower than that observed for the mode of 6'ON/12'OFF.

Composição de cana-de-açúcar para alimentação animal em função da aplicação de bactérias diazotróficas / Composition of sugarcane for animal feeding with the application of diazotrophic bacteria

A cana-de-açúcar pode ser empregada na alimentação animal devido ao seu alto rendimento de matéria seca. No entanto, há muitas recomendações para evitar o emprego como alimento para animais de bom potencial genético, pois apresenta baixo teor proteico e de minerais, bem como e fibra de baixa qualidade. Desta forma, o objetivo deste trabalho foi avaliar os efeitos da aplicação de uma mistura de cinco bactérias diazotróficas (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) e da adubação nitrogenada sobre a produção, maturação e composição químico-bromatológica de cinco variedades de cana-de-açúcar com potencial para serem empregadas na alimentação animal. Os tratamentos foram formados conforme a combinação dos cinco genótipos de cana-de-açúcar (RB867515, RB966928, RB106814, RB106818 e RB106819) com quatro condições de inoculação e adubação nitrogenada em cobertura. Os teores de sólidos solúveis totais foram determinados dos 180 dias após o transplante até a colheita do experimento, onde foi avaliada a produtividade e a amostragem de material foi coletada para as avaliações químico-bromatológicas: matéria seca, nitrogênio acumulado, proteína bruta, fibra em detergente neutro, fibra em detergente ácido, holocelulose, celulose, hemicelulose, lignina, extrativos totais e cinzas. De acordo com os resultados deste estudo, conclui-se que a aplicação de bactérias diazotróficas de forma isolada ou em conjunto com a adubação nitrogenada, aumenta a produtividade e os sólidos solúveis totais, antecipando a maturação, além de melhorar a composição químico-bromatológica das plantas de cana-de-açúcar.

Sugarcane can be used in animal feed due to its high dry matter yield. However, there are many recommendations to avoid its use as food for animals with good genetic potential, since it has a low contents of protein and minerals, as well as fiber of low quality. Therefore, this work aimed to evaluate the effects of applying a mixture of five diazotrophic bacteria (Gluconacetobacter diazotrophicus; Herbaspirillum seropedicae; Herbaspirillum rubrisubalbicans; Paraburkholderia tropica; Nitrospirillum amazonense) and nitrogen fertilization on the production, maturation, and chemical-bromatological composition of five sugarcane varieties with potential to be used in animal feed. The treatments were formed according to the combination of the five sugarcane genotypes (RB867515, RB966928, RB106814, RB106818, and RB106819) with four conditions of inoculation and nitrogen fertilization in coverage. The levels of total soluble solids were determined from 180 days after transplantation until the harvest of the experiment, where productivity was evaluated and the sample material was collected for chemical-bromatological evaluations: dry matter, accumulated nitrogen, crude protein, neutral detergent fiber, acid detergent fiber, holocellulose, cellulose, hemicellulose, lignin, total extracts, and ashes. According to the results of the present study, it is concluded that the application of diazotrophic bacteria alone or in conjunction with nitrogen fertilization, increases productivity and total soluble solids, anticipating maturation, in addition to improving the chemical-bromatological composition of sugarcane plants.

Transesterification of castor oil catalyzed by a fermented solid produced by Burkholderia contaminans using a bioreactor coupled with ultrasound irradiation.

In this work, ultrasound was used to assist the ethanolysis of castor oil in a solvent-free system, catalyzed by a dry fermented solid containing the lipase from Burkholderia contaminans (BCFS). Reactions were done at 45°C. The maximum conversion in Erlenmeyer flasks was 71% in 96 h, using a loading of 9% (mass of BCFS in relation to the mass of triacylglycerols in the castor oil) and a molar ratio of ethanol:oil of 6:1, with addition of ethanol in 12 steps. In a packed-bed reactor containing 12 g of BCFS, the conversions were 78% in 48 h, and 83% in 72 h with an ethanol to oil molar ratio of 3:1 and treatment with an ultrasound probe, with maximum power of 500 W, frequency of 20 kHz, and 75% of the maximum power. These results are promising given that, with an ultrasound assisted bioreactor, a higher conversion in a shorter time was achieved, with a lower ethanol to oil molar ratio than was the case in the Erlenmeyer flasks without ultrasound.

Improving postharvest life, quality and bioactive compounds of strawberry fruits using spermine and spermidine / Melhorando as condições de vida pós-colheita, qualidade e compostos bioativos de frutos de morango usando espermina e espermidina

Abstract Small fruits such as strawberries, are a good source of natural antioxidants. In recent decades, many efforts have been made to increase the shelf life of strawberries and maintain its nutritional value in post-harvest conditions. In the present study, the effects of spermine (Spm) and spermidine (Spd) (0, 1.0 and 1.5 mM) on the post-harvest life and quality of strawberry fruits during the 3rd, 6th, and 12th days of storage, were investigated. Applications of Spm and Spd decreased the rate of weight loss, fruit decay, soluble solids content, fruit juice pH and taste index during the storage period in compared to the control. However, titratable acids and vitamin C contents, tissue stiffness, phenolic compounds and antioxidant activity increased in compared to the control. These growth regulators prevented the aging and loss of bioactive compounds of the fruit by increasing the antioxidant activity and preventing the destruction of the fruit tissue. Among the studied treatments, applications of 1.5 mM of Spm and Spd were the most effective treatments to enhance the storage life and quality characters of strawberry fruits.

RESUMO Frutas pequenas como morangos são uma boa fonte de antioxidantes naturais. Nas últimas décadas, muitos esforços têm sido feitos para aumentar sua vida útil e manter seu valor nutricional em condições de pós-colheita. No presente estudo, foram investigados os efeitos da espermina (Spm) e espermidina (Spd) (0, 1,0 e 1,5 mm) pós-colheita e na qualidade dos frutos de morango durante o 3º, 6º e 12º dias de armazenamento. Aplicações de Spm e Spd diminuíram a taxa de perda de peso, podridão dos frutos, teor de sólidos solúveis, pH do suco de frutas e índice de sabor durante o período de armazenamento em comparação com o controle. No entanto, os teores de ácidos tituláveis e vitamina C, rigidez tecidual, compostos fenólicos e atividade antioxidante aumentaram em relação ao controle. Esses reguladores de crescimento preveniram o envelhecimento e a perda de compostos bioativos da fruta, aumentando a atividade antioxidante e evitando a destruição do tecido da fruta. Entre os tratamentos estudados, as aplicações de 1,5 mm de Spm e Spd foram os tratamentos mais eficazes para aumentar a vida de armazenamento e as características de qualidade dos frutos de morango.

Peligros microbiológicos relacionados con alimentos fermentados de elaboración artesanal comercializados en Tunja, Nariño y Cauca / Microbiological risks related to artisanal fermented foods marketed in Tunja, Nariño and Cauca

RESUMEN Varios factores intervienen en la calidad de los alimentos, como los físicos, químicos, nutricionales, sensoriales y microbiológicos. Este último es importante, ya que, afecta las propiedades organolépticas del producto terminado y, además, puede ocasionar riesgos de salud pública asociados a peligros microbiológicos. Colombia es un país rico en gastronomía, incluyendo alimentos fermentados de elaboración artesanal (AFEA), los cuales son una alternativa actual para sistemas agroalimentarios que buscan alimentos más naturales. El objetivo de este estudio fue evaluar los criterios microbiológicos en AFEA y el cumplimiento de requisitos sanitarios para sensibilizar a productores de bebidas artesanales y revalorizar los productos. Se tomaron en cuenta 11 productores artesanales de Masato, Champús y Almidón agrio de yuca en zonas rurales del país, que voluntariamente aceptaron participar. Se midieron los parámetros de pH, humedad, sólidos solubles y recuentos microbiológicos. Con estos resultados, se pudo calcular el porcentaje de conformidad de los alimentos, de los cuales el 36 % de productos evaluados fueron aptos para el consumo. Se incumplieron los límites establecidos para Escherichia coli, Staphylococcus aureus, Bacillus cereus y Salmonella sp. Los análisis fisicoquímicos mostraron que el Masato y el Champús aportan condiciones abióticas para el crecimiento microbiano. Además, los productores Almidón agrio de yuca tuvieron mayor valoración en el cumplimiento de requisitos sanitarios y menor cumplimiento que los productores de Champús. Los análisis realizados indican que la mayoría de los alimentos incumplieron los límites permitidos por lo cual se debe capacitar a los productores en buenas prácticas de manufactura.

ABSTRACT Several factors intervene in the quality of the food, such as physical, chemical, nutritional, sensory, and microbiological. The latter is important as it affects the sensory properties of the finished product, and it can also cause public health risks associated with microbiological hazards. Colombia is a country rich in gastronomy, including artisanal fermented foods (AFEA), which are a current alternative for agri-food systems seeking for more natural foods. The objective of this study was to evaluate the microbiological criteria in AFEA and its compliance with the sanitary requirements to raise the awareness among crafted beverages producers and revalue the products. Eleven artisan producers of masato, champús and sour cassava starch in rural areas of the country, who voluntarily agreed to participate, were considered. The parameters of pH, humidity, soluble solids, and microbiological counts were measured. With these results, it was possible to calculate the compliance rate of the food, from which 36% of the products evaluated were fit for consumption. The limits established for Escherichia coli, Staphylococcus aureus, Bacillus cereus and Salmonella spp were breached. Physicochemical analysis showed that Masato and Champús provide abiotic conditions for microbial growth. In addition, the Sour cassava starch producers had higher compliance ratings regarding sanitary requirements but lower compliance ratings than champús producers. The performed analysis indicates that most of the food did not comply with the permitted limits, which is why producers must be trained in good manufacturing practices.

Establecimiento de biofloc a tres relaciones carbono/nitrógeno, tendiente a la producción de zooplancton / Establishment of biofloc at three carbon/nitrogen ratios, tending to the production of zooplankton

RESUMEN El objetivo de esta investigación fue establecer el biofloc a tres relaciones carbono/ nitrógeno (C/N): 10/1, 15/1 y 20/1, determinando la secuencia de remoción de N, el perfil de sólidos y la caracterización del zooplancton, para tal fin se dispuso de tres tanques con volumen de 7000 L, incorporando oxígeno al agua a través de un aireador tipo soplador. Se utilizó como fuente de N balanceado, fuente de carbono melaza y bicarbonato de sodio como fuente alcalinizante. Al inicio se incrementó el nitrógeno amoniacal total NAT a 2 mg/L, la alcalinidad total (AT) a 120 mg/L y se adicionó como inóculo 10 litros/tanque de agua proveniente de un estanque de cultivo, al sexto y décimo días se adicionó balanceado incrementando teóricamente el NAT en 4 mg/L y a partir del día 12 en 1 mg/L. En las tres relaciones C/N se evidenciaron procesos de nitrificación durante la estabilización del biofloc, hasta llegar en el tiempo a concentraciones no letales de amonio y nitrito para peces, menores a 1 mg/L. En cuanto a los sólidos volátiles, se encontró una mayor concentración en la relación 20/1, lo cual puede atribuirse a la mayor adición de melaza, con la consecuente producción de SSV a partir de la dominancia de comunidades heterotróficas, en los tres macrocosmos se presentaron comunidades del zooplancton, no obstante, el T2 presentaron la mayor abundancia y riqueza de organismos. Las tres relaciones C/N en biofloc establecieron condiciones de calidad de agua y alimento vivo.

ABSTRACT The objective of this research was to establish the biofloc at three carbon/nitrogen (C/N) relationships: 10/1, 15/1 and 20/1, determining the N removal sequence, the solids profile and the characterization of the zooplankton, for this purpose three tanks with a volume of 7000 L were available, incorporating oxygen into the water through a blower-type aerator. It was used as a source of balanced N, a source of carbon molasses and sodium bicarbonate as an alkalizing source. At the beginning, the total ammoniacal nitrogen NAT was increased to 2 mg/L, the total alkalinity (AT) to 120 mg/L and 10 liters / tank of water from a culture pond was added as inoculum, on the sixth and tenth days it was he added balanced, theoretically increasing the NAT by 4 mg/L and from day 12 by 1 mg/L. In the three C / N relationships, nitrification processes were evidenced during the stabilization of the biofloc, until reaching non-lethal concentrations of ammonium and nitrite for fish, less than 1 mg/L in time. Regarding volatile solids, a higher concentration was found in the 20/1 ratio, which can be attributed to the greater addition of molasses, with the consequent production of SSV from the dominance of heterotrophic communities, in the three macrocosms there were Zooplankton communities, however, T2 presented the highest abundance and richness of organisms. The three C / N relationships in biofloc established conditions of water quality and live food.

Estimation of Soluble Solids for Stone Fruit Varieties Based on Near-Infrared Spectra Using Machine Learning Techniques.

The quality control for fruit maturity inspection is a key issue in fruit packaging and international trade. The quantification of Soluble Solids (SS) in fruits gives a good approximation of the total sugar concentration at the ripe stage, and on the other hand, SS alone or in combination with acidity is highly related to the acceptability of the fruit by consumers. The non-destructive analysis based on Visible (VIS) and Near-Infrared (NIR) spectroscopy has become a popular technique for the assessment of fruit quality. To improve the accuracy of fruit maturity inspection, VIS−NIR spectra models based on machine learning techniques are proposed for the non-destructive evaluation of soluble solids in considering a range of variations associated with varieties of stones fruit species (peach, nectarine, and plum). In this work, we propose a novel approach based on a Convolutional Neural Network (CNN) for the classification of the fruits into species and then a Feedforward Neural Network (FNN) to extract the information of VIS−NIR spectra to estimate the SS content of the fruit associated to several varieties. A classification accuracy of 98.9% was obtained for the CNN classification model and a correlation coefficient of Rc>0.7109 for the SS estimation of the FNN models was obtained. The results reported show the potential of this method for a fast and on-line classification of fruits and estimation of SS concentration.

Adsorption of basic fuchsin using soybean straw hydrolyzed by subcritical water.

The valorization of agro-industrial residues can be improved through their full use, making the production of second-generation ethanol viable. In this scenario, hydrolyzed soybean straw generated from a subcritical water process was applied to the basic fuchsin adsorption. At pH eight, a high adsorption capacity was obtained. The mass test results showed that basic fuchsin's removal and adsorption capacity could be maximized with an adsorbent dosage of 0.9 g L-1. The linear driving force model was suitable for predicting the kinetic profile, and the kinetic curves showed that equilibrium was reached with only 30 min of contact time. Besides, the Langmuir model was the best to predict the adsorption isotherms. The thermodynamic parameters revealed a spontaneous and endothermic process. At 328 K, there is maximum adsorption capacity (72.9 mg g-1). Therefore, it can be stated that this material could be competitive in terms of adsorption capacity coupled with the idea of full use of waste.

A video processing and machine vision-based automatic analyzer to determine sequentially total suspended and settleable solids in wastewater.

The monitoring of total suspended (TSS) and settleable (SetS) solids in wastewater is essential to maintain the quality parameters for aquatic biota because they can transport pollutants and block light penetration. Determining them by their respective reference methods, however, is laborious, expensive, and time consuming. To overcome this, we developed a new analytical instrument called Solids in Wastewater's Machine Vision-based Automatic Analyzer (SWAMVA), which is equiped with an automatic sampler and a software for real-time digital movie capture to quantify sequentially the TSS and SetS contents in wastewater samples. The machine vision algorithm (MVA) coupled with the Red color plane (derived from color histograms in the Red-Green-Blue (RGB) system) showed the best prediction results with R2 of 0.988 and 0.964, and relative error of prediction (REP) of 6.133 and 9.115% for TSS and SetS, respectively. The constructed models were validated by Analysis of Variance (ANOVA), and the accuracy and precision of the predictions by the t- and F-tests, respectively, at a 0.05 significance level. The elliptical joint confidence region (EJCR) test confirmed the accuracy, while the coefficient of variation (CV) of 6.529 and 10.908% confirmed the good precisions, respectively. Compared with the reference method (Standard Methods For the Examination of Water and Wastewater), the proposed method reduced the analysis volume from 1.5 L to just 15 mL and the analysis time from 12 h to 24 s per sample. Therefore, SWAMVA can be considered an important alternative to the determination of TSS and SetS in wastewater as an automatic, fast, and low-cost analytical tool, following the principles of Green Chemistry and exploiting Industry 4.0 features such as intelligent processing, miniaturization, and machine vision.

Qualidade do leite cru refrigerado avaliado por diferentes laboratórios credenciados pelo MAPA / Quality of refrigerated raw milk evaluated by different laboratories accredited by MAPA

O objetivo deste trabalho foi analisar e correlacionar os resultados de qualidade do leite cru refrigerado de dez propriedades rurais de Viçosa (MG) obtidos por métodos de referências do Ministério da Agricultura, Pecuária e Abastecimento e por espectrofotômetros de luz infravermelha em três laboratórios (A, B e C) credenciados pelo mesmo órgão de fiscalização. As amostras de leite foram analisadas quanto à contagem bacteriana, contagem de células somáticas (CCS) e teores de gordura, proteína e extrato seco desengordurado (ESD). Não houve discordância de amostras de leite quanto aos teores de proteína e gordura. Porcentagens diferentes de discordância foram observadas entre os resultados dos laboratórios e método de referência quanto à CCS, contagem bacteriana e teores de ESD. Os teores médios de proteína dos laboratórios A e B e os teores médios de ESD de todos laboratórios não foram estatisticamente iguais (p<0,05) aos teores obtidos pelo método de referência. Os teores de gordura obtidos no laboratório B não tiveram correlação estatística (p>0,05) com os teores obtidos pelo método de referência. Observou-se que as CCS e contagens bacterianas médias de todos os laboratórios foram estatisticamente iguais (p>0,05) e correlacionadas (p<0,05) às contagens médias obtidas pelos métodos de referência. Conclui-se que os teores de proteína em dois laboratórios e ESD em todos os laboratórios não são equivalentes com os métodos de referência do MAPA. É importante que os laboratórios revejam a calibração dos seus equipamentos quanto à quantificação dos teores de sólidos do leite.

The objective of this study was to analyze and to correlate the results of refrigerated raw milk quality in ten farms of Viçosa (MG). The milk was analyzed by the Ministério da Agricultura, Pecuária e Abastecimento standard methods and by infrared spectrophotometers in three laboratories (A, B and C) accredited by the same institution. The milk samples were analyzed for bacterial counts, somatic cell count (SCC) and fat, protein and solids not fat (SNF) tenors. There were no disagreement milk samples as the protein and fat tenors. Different percentages of disagreement were observed between the results of laboratory and standard method as the SCC, bacterial count and SNF tenor. The protein mean tenor of A and B laboratories and the SNF mean tenor of all laboratories were not statistically equal (p<0.05) the tenors obtained by standard method. The fat tenors obtained in B laboratory were not statistically correlated (p>0.05) with tenors obtained by the standard method. It was observed that the means of SCC and bacterial counts of all laboratories were statistically the same (p>0.05) and correlated (p<0.05) to the means counts obtained by standard methods. It is concluded that the protein tenors in two laboratories and SNF in all laboratories are not equivalent with the reference methods of MAPA. It is important that laboratories review the calibration of the equipment on the quantification of milk solids tenors.

Esmeralda Peach (Prunus persica) Fruit Yield and Quality Response to Nitrogen Fertilization.

'Esmeralda' is an orange fleshed peach cultivar primarily used for juice extraction and secondarily used for the fresh fruit market. Fruit yield and quality depend on several local environmental and managerial factors, mainly on nitrogen, which must be balanced with other nutrients. Similar to other perennial crops, peach trees show carryover effects of carbohydrates and nutrients and of nutrients stored in their tissues. The aims of the present study are (i) to identify the major sources of seasonal variability in fruit yield and qu Fruit Tree Department of Federal University of Pelotas (UFPEL), Pelotas 96010610ality; and (ii) to establish the N dose and the internal nutrient balance to reach high fruit yield and quality. The experiment was conducted from 2014 to 2017 in Southern Brazil and it followed five N treatments (0, 40, 80, 120 and 160 kg N ha-1 year-1). Foliar compositions were centered log-ratio (clr) transformed in order to account for multiple nutrient interactions and allow computing distances between compositions. Based on the feature ranking, chilling hours, degree-days and rainfall were the most influential features. Machine learning models k-nearest neighbors (KNN) and stochastic gradient decent (SGD) performed well on yield and quality indices, and reached accuracy from 0.75 to 1.00. In 2014, fruit production did not respond to added N, and it indicated the carryover effects of previously stored carbohydrates and nutrients. The plant had a quadratic response (p < 0.05) to N addition in 2015 and 2016, which reached maximum yield of 80 kg N ha-1. In 2017, harvest was a failure due to the chilling hours (198 h) and the relatively small number of fruits per tree. Fruit yield and antioxidant content increased abruptly when foliar clrCu was >-5.410. The higher foliar P linearly decreased total titratable acidity and increased pulp firmness when clrP > 0.556. Foliar N concentration range was narrow at high fruit yield and quality. The present results have emphasized the need of accounting for carryover effects, nutrient interactions and local factors in order to predict peach yield and nutrient dosage.

Anaerobic co-digestion of swine manure and forage at two harvesting ages / Co-digestão anaeróbia dos dejetos de suínos e forragem em duas idades de colheita

The co-digestion of swine manure with vegetable waste is an alternative that can increase the production of biogas and methane generated by the isolated digestion of manure. However, recommendations that are based on the best ratio between manure and forage, as well as the age of harvest, are still scarce in the literature. This study was conducted to evaluate inclusions (0, 25, 50, 75 and 100%) of the total solids (TS) of Elephant grass (Pennisetum purpureum Schum) harvested at two ages medium age (MA) at 45 days of growth and advanced age (AA) at 90 days in co-digestion with swine manure, using an entirely randomized design in a 5x2 factorial scheme. Batch digesters were used and biogas production was monitored for 12 weeks. There was influence of forage age (P <0.05) on the degradation of solids and neutral detergent fiber, with higher values for the substrates containing MA forage. The highest CH4 yields were obtained by the substrates containing MA forage in the inclusion of 27.7 and 31.6%, being 253.7 and 222.2 L of CH4 per Kg of total or volatile solids. The age of the forages influenced the onset and persistence of biogas production, being advantageous only in the inclusion of 25% of MA forage. The AA forage inclusion is not recommended for co-digestion with swine manure.

A co-digestão dos dejetos suínos associados a resíduos vegetais é uma alternativa que pode elevar as produções de biogás e metano alcançadas pela digestão isolada do dejeto. No entanto, recomendações que se baseiem na melhor proporção entre dejeto e forragem, assim como na idade de colheita ainda são escassas na literatura. O objetivo do trabalho foi avaliar inclusões crescentes (0, 25, 50, 75 e 100% dos sólidos totais (ST) de capim elefante (Pennisetum purpureum Schum.) colhido em duas idades de corte mediana (MA) aos 45 dias de crescimento e avançada (AA) aos 90 dias, empregado em co-digestão com o dejeto suíno, adotando-se delineamento inteiramente ao acaso, em esquema fatorial 5x2. Foram utilizados biodigestores batelada de bancada, sendo as produções de biogás acompanhadas durante 12 semanas. Houve influência da idade da forragem (P<0,05) na degradação de sólidos e fibra em detergente neutro, com maiores valores para os substratos que continham a forragem MA. Os maiores rendimentos de CH4 foram alcançados pelos substratos que continham forragem MA na inclusão de 27,7 e 31,6 %, sendo de 253,7 e 222,2 L de CH4 por Kg de ST ou sólido volátil adicionado. A idade das forragens influenciou o início e a persistência das produções de biogás ao longo do período de digestão, sendo vantajosa apenas na inclusão de 25% de forragem com MA.

Temporal Gene Expression in Apical Culms Shows Early Changes in Cell Wall Biosynthesis Genes in Sugarcane.

Multiple genes in sugarcane control sucrose accumulation and the biosynthesis of cell wall components; however, it is unclear how these genes are expressed in its apical culms. To better understand this process, we sequenced mRNA from +1 stem internodes collected from four genotypes with different concentrations of soluble solids. Culms were collected at four different time points, ranging from six to 12-month-old plants. Here we show differentially expressed genes related to sucrose metabolism and cell wall biosynthesis, including genes encoding invertases, sucrose synthase and cellulose synthase. Our results showed increased expression of invertases in IN84-58, the genotype with lower sugar and higher fiber content, as well as delayed expression of secondary cell wall-related cellulose synthase for the other genotypes. Interestingly, genes involved with hormone metabolism were differentially expressed across time points in the three genotypes with higher soluble solids content. A similar result was observed for genes controlling maturation and transition to reproductive stages, possibly a result of selection against flowering in sugarcane breeding programs. These results indicate that carbon partitioning in apical culms of contrasting genotypes is mainly associated with differential cell wall biosynthesis, and may include early modifications for subsequent sucrose accumulation. Co-expression network analysis identified transcription factors related to growth and development, showing a probable time shift for carbon partitioning occurred in 10-month-old plants.