This study aimed to produce biochar with an energy value in the range of sub-bituminous carbon by investigating the effect of oxidative and non-oxidative torrefaction on the torrefaction yield and fuel properties of wheat straw. Three independent variables were considered at different levels: temperature (230, 255, 280, 305 °C), residence time (20, 40, 60 min), and reaction atmosphere (0, 3, 6 vol% O₂; N₂ balance); and three dependent variables: mass yield, energy yield, and percentage increase in higher heating value (HHV). The results showed that it is possible to produce a sub-bituminous carbon type C biochar using oxidative torrefaction, significantly reducing time and temperature compared with non-oxidative torrefaction. The optimum torrefaction conditions were 287 °C–20 min–6.0% O₂, which increased the HHV of wheat straw from 13.86 to 19.41 MJ kg⁻¹. The mass and energy yields were 44.11 and 61.78%, respectively. The physicochemical and fuel properties of the obtained biochar were improved compared with the raw biomass. The atomic O/C ratio was reduced from 1.38 to 0.86. In addition, the hydroxyl groups in the lignocellulosic structure decreased and the hemicellulose content decreased from 26.08% to 1.61%. This improved grindability, thermal stability, porosity, and hydrophobicity.

The capacity of untreated cotton stalk to remove and adsorb Cu²⁺ ions in synthetic and natural aqueous solutions was evaluated. The influence of three sensitive parameters of the adsorption process—solution pH, adsorbent dosage, and contact time—on the percentage of Cu²⁺ removal in agricultural wastewater, livestock wastewater, and synthetic samples was studied. Physicochemical and morphological properties were studied using thermogravimetry, Fourier infrared spectrophotometry, and scanning electron microscopy. The elemental composition, proximal composition, zero charge point, and acid–base sites were determined. In addition, kinetic studies were performed, and the adsorption equilibrium was analyzed. The optimum conditions for Cu²⁺ adsorption were the following: solution pH = 5.5, adsorbent dosage of 0.6 g, and contact time of 60 min. Under these conditions, the percentage of Cu²⁺ removal in synthetic samples was 66.5% when the initial copper concentration was 50 mg/L. The removal percentage in agricultural and livestock wastewater samples was 87.60% and 85.05%, respectively, when the initial copper concentration was 25 mg/L. The adsorption data are consistent with the Freundlich isotherm model, which achieved a quadratic fit of 0.991 compared to 0.5542 for the Langmuir model. The experimental results indicate that the adsorption adequately fits the pseudo-second-order kinetic model. The results suggest that cotton stalks are a promising adsorbent for the ecological and economical removal of Cu²⁺ in wastewater. This research, therefore, provides relevant information that contributes to the sustainable management of agricultural waste and instills hope for a reduction in water pollution from heavy metals derived from agricultural activities.

Selenium is an essential micronutrient which is found in many foods and beverages in low concentrations. Craft beer, one of the most widely consumed fermented beverages globally, presents a strategic opportunity for selenium intake through organic nanoparticles. This study aimed to confirm the presence of selenium nanoparticles in the fermentation process of an ale-style beer using S. boulardii yeast selenized with Na₂SeO₃ (74 ppm), through spectroscopic analysis and TEM. The yeast accumulated 5.92 mg/g of dry cell mass, and the beer contained 0.642 mg/g of selenium. UV-VIS detected nanoparticles with a peak at 300 nm and FT-IR at a wavelength of 1398.85 cm⁻¹. The particle size ranged between 74 to 175 nm, with a maximum ζ-potential of −4.2 mV, an electrophoretic mobility of −0.3492 μm × cm Vs⁻¹, and a conductivity of 2.656 mS cm⁻¹. TEM analysis revealed that the nanoparticles exhibited circular/ovoid shapes. The fermentation process, combined with the ingredients used to produce ale-type craft beer, proved to be a feasible method for the biosynthesis of selenium nanoparticles using S. boulardii, offering a reliable option for developing and innovating functional craft beers.

The style of a beer is determined by the combination of malts and hops, and the type of yeast used. The incorporation of date fruits into the fermentation process with non-conventional yeasts such as Lachancea spp. results in effective fermentation, influencing the kinetic parameters of yeast growth and prompting different physicochemical properties in the resulting beverage. The brewing process for a sour beer with Lachancea spp. yeast was optimized using a central composite rotational design and response surface methodology, and the growth kinetics were calculated. The optimal conditions required 500 g of dates, incorporated 59.46 h after starting the fermentation process. The results revealed a total phenolic content of 254.81 mg GAE/g, and the amount of titratable acidity was 2.66%. Under favorable operating conditions, the growth kinetic parameters of Lachancea spp. yeast revealed a rate of 0.78 μ.h⁻¹ and a growth constant of 3.29 k (g/h). The addition of dates 60 h into fermentation with Lachancea spp. allows for technical control of acidity and efficient fermentation kinetics for the creation of sour craft beers.

Objective: To assess date losses during harvest and identify the factors causing them. Design/methodology/approach: A complete randomized block design with ten repetitions was used; the different farms where data on the evaluated variables were taken were the treatments. In each treatment, 10 plants were selected from which data on average fruit weight, polar and equatorial fruit diameter, fruit weight, number of clusters per plant, and yield in tons per hectare were taken. Results: For yield in tons per hectare of good fruits during the date harvest in the 2023 cycle, an average of 11 t ha-1, 14 t ha-1, 8 t ha-1, and 15 t ha-1 was found for the plantations of El Pólvora, El Pino, Las Palmas and Cucapah respectively. In losses during the harvest, Cucapah Farm presented the highest losses with an average of 1.2 t ha-1, while El Pino was the one that presented the lowest losses with an average of 0.7 t ha-1. Fruits with a percentage greater than 10% of peeled skin are also considered losses during the harvest, because they cannot be marketed for fresh consumption. Limitations on study/implications: Data were collected only from the harvest; exact dates of irrigation and fertilizer application are not available as the study was conducted with cooperating producers. This factor is crucial for the quality and yield of date palm cultivars. Findings/conclusions: The age of the plant represents a significant difference in the yield per hectare due to the number of clusters it has; the more clusters it has, the higher the yield. The relative humidity directly affects the quality of the dates, and there are a more significant number of bulging fruits (with peeled skin). In this evaluation, we found that the rains during August and September 2023 significantly affected the losses during the date harvest in that season.