Explore the vast range of titles available.

With the aim of identifying new sources to produce cellulose nanofibers, olive tree pruning biomass (OTPB) was proposed for valorization as a sustainable source of cellulose. OTPB was subjected to a soda pulping process for cellulose purification and to facilitate the delamination of the fiber in the nanofibrillation process. Unbleached and bleached pulp were used to study the effect of lignin in the production of cellulose nanofibers through different pretreatments (mechanical and TEMPO-mediated oxidation). High-pressure homogenization was used as the nanofibrillation treatment. It was observed that for mechanical pretreatment, the presence of lignin in the fiber produces a greater fibrillation, resulting in a smaller width than that achieved with bleached fiber. In the case of TEMPO-mediated oxidation, the cellulose nanofiber characteristics show that the presence of lignin has an adverse effect on fiber oxidation, resulting in lower nanofibrillation. It was observed that the crystallinity of the nanofibers is lower than that of the original fiber, especially for unbleached nanofibers. The residual lignin content resulted in a greater thermal stability of the cellulose nanofibers, especially for those obtained by TEMPO-mediated oxidation. The characteristics of the cellulose nanofibers obtained in this work identify a gateway to many possibilities for reinforcement agents in paper suspension and polymeric matrices.

Under climate change threats, there is a growing need to adapt the conventional agronomic practices used in rainfed olive orchards by sustainable practices, in order to ensure adequate crop yield and olive oil quality and to preserve soil health. Therefore, for two years, the effects of conventional tillage practice (T) and two sustainable soil management strategies, a leguminous cover crop (LC) and its combination with natural zeolites (ZL), on the yield, fatty acid composition, polyphenolic profile and quality indices of olive fruits and oil were evaluated. Crop yield was significantly increased by LC and ZL in the first year. Although in the second year no significant differences were verified, the cumulative yield increased significantly by 31.6% and 35.5% in LC and ZL trees, respectively. LC enhanced the moisture and size of olives, while ZL increased, in general, the concentrations of oleuropein, verbascoside, caffeic acid and epicatechin, as well the oleic/linoleic ratio in fruits and the levels of 3,4-dihydroxyphenylglycol, tyrosol, verbascoside and caffeic acid in olive oil. Despite the higher concentration of total phenols in the fruits and oil from T trees in the warmer and dryer year, the quality of the oil decreased, mainly when compared with ZL, as evidenced by the peroxide value and K232 and K270 coefficients. In short, both sustainable soil management strategies appear to be promising practices to implement in olive orchards under rainfed conditions, but the innovative strategy of combining zeolites with legume cover crops, first reported in the present study, confers advantages from a nutritional and technological point of view. Nevertheless, studies subjected to the long-term use of these practices should be conducted to ensure the sustainability of the crop yield and olive oil quality.

In the production sector, the usefulness of predictive systems as a tool for management and decision-making is well known. In the agricultural sector, a correct economic balance of the farm depends on making the right decisions. For this purpose, having information in advance on crop yields is an extraordinary help. Numerous predictive models infer accurate crop yield data from aerobiological variables and pollen analysis; this is around spring, in the middle stage of the crop year, when planning and investments are already done. The aim of this study is to anticipate accurate crop yield data at an early stage of the cropping season. In the case of olive groves in Spain, this period is in February. This work is developed for an entire province, Jaen, belonging to the region of Andalusia, in Southern Spain. The methodology uses Machine Learning algorithms together with an exhaustive analysis of predictor variables. Temporal data come from public web services, such as spatial data infrastructures of some state agencies. The processing of the satellite imagery is carried out by the geospatial processing service Google Earth Engine. The result is the early prediction of kilograms of both olive crop and olive oil, eight months prior to the beginning of the first harvesting campaigns of the year, with an average absolute error of prediction better than 26%. The relevance of this work is the early availability of predicted crop yield data together with the multi-scale applicability of the predictive models. This makes this model a useful tool for all the agents involved in olive grove management. From farmers, to agricultural technicians, researchers and scientists dedicated to the study of the olive tree, to governmental institutions and agricultural associations that provide technical support, advice and regulation to ensure responsible practices and the long-term viability of the olive industry.

The production of olive oil involves the sustainable management of the waste produced along the entire production chain. This review examines the developments regarding cultivation techniques, production technologies, and waste management, highlighting the goals to be achieved and the most reasonable prospects. The results show that cultivation and production technology have evolved to an almost final solution to meet economic feasibility, keeping the oil’s high quality. Continuous horizontal decanters will coexist with traditional mills in many countries with old olive oil production and consumption traditions. High-quality products have conquered markets, especially in the wealthiest countries. At the same time, the exploitation of dried pomace by solvent extraction is increasingly an obsolete practice. However, waste management is still looking for one or a few reasonable solutions that meet modern society’s constraints. The enhancement of some experienced technologies and the full-scale application of emerging technologies and strategies should solve this problem in the short–medium term. A short discussion is reported on the possibility of unifying the nature and the quality of the waste, whatever the olive oil production method is. Furthermore, modern thermochemical treatment for solid wet organic waste disposal is examined and discussed.

Phenolics, volatiles, squalene, tocopherols, and fatty acids of virgin olive oils (VOO) from adult and young olive trees of the Oueslati variety, typically cultivated in the Center of Tunisia, were analyzed at three different harvesting periods. Significant differences in contents of saturated fatty acids ( p  < 0.05), squalene ( p  < 0.05), alpha-tocopherol and total tocopherol ( p  < 0.02) and oxidized form of decarboxymethyl oleuropein aglycon ( p  < 0.05) were seen between VOO from adult and young trees during maturation. Moreover, the volatile profiles of VOO from adult and young trees showed significant differences in the amounts of hexanal, 1-penten-3-ol ( p  < 0.05), ( Z )-3-hexenal and ( Z )-2-penten-1-ol ( p  < 0.01). Principal component analysis showed that olives from adult trees should be harvested at the cherry stage of maturation to obtain a satisfactory level of oil quality, while olives from young trees should be harvested at the black maturation stage.

A mathematical analysis was conducted to predict the power requirements of the olive trunk shaker. The predicted required power of the olive trunk shaker is influenced by shaking displacement, fruit detachment force, fruit mass, stem length, damping ratio, unbalanced mass of the tree shaker, and exciting shaking frequency. The Olive trunk shaker was tested in the field at five attachment heights, 400, 500, 600, 700, and 800 mm, and six levels of olive trunk diameter: 78, 84, 101, 143, 158, and 186 mm. The results indicated that the theoretical shaking power was 12.8 kW while the actual required shaking power ranged from 7.1 to 17.8 kW, with an average of 12.6 kW due to variations in tree trunk diameters and different attachment heights. Multiple regression using the least squares method was employed to establish a statistical relation between the theoretical equation and the actual required power as a function of the clamp attachment height and trunk diameter. The regression coefficient of the predicted equation was 93.6% for attachment height values between 400 and 800 mm and tree trunk diameter values between 78 and 186 mm, with a mean absolute error of the prediction model was 0.5009 kW.

In Lebanon, olive oil plays an essential role at both economic and social levels. However, factors influencing its quality are rarely addressed. This preliminary study is the first analysis to show a comparison between ancient and adult virgin olive oil trees in Lebanon. Analysis of pedo-climatic conditions and physicochemical parameters of virgin oil samples taken from ancient and adult trees from three Lebanese regions (Bechmizine, Kfaraaka, and Kawkaba) and at two different harvest periods showed that these parameters differed significantly among cultivation regions, while the tree age and harvest time had a lower effect. We observed that the oil obtained from adult trees of Kawkaba region during the first harvest period (green to reddish stage of fruit maturity) had the best quality, compared to all other samples. Oil produced from these trees showed the highest polyphenol content, a relatively higher composition of tocopherols, oleic acid, monounsaturated fatty acids, and trans fatty acids C18: 1–C18: 2, with relatively low acidity and peroxide values. It was concluded that the quality of virgin olive oil was associated with its chemical composition, and was the result of a complex interaction between several environmental factors associated with the area of cultivation, tree age, and harvest time.

A trunk-vibrating screen is widely used in olive harvesting machinery. Because of the irregularity of fruit recovery efficiency, the recovery efficiency fluctuates greatly. Vibration harvesting parameters are important factors affecting the percentage of olive harvest. Therefore, the study of vibration picking parameters is of great significance for olive harvest. Vibration parameters, governed by tree morphological parameters, strongly influence the efficiency of vibration harvesting. In this study, a combination of response surface simulation and harvesting experiments was used to investigate the relationship between morphological and vibration harvesting parameters in \"three open-center shape\" olive trees. First, force analysis and experimental measurements were performed on the olive fruit, and the Box-Behnken design was used to obtain the vibration parameters through finite element simulation and to establish the response surface model of the parameters (main trunk diameter, main trunk height, main branch angles A and E) and the vibration parameters (vibration frequency and vibration force) of the \"three open-center-shape\" olive trees. In addition, the mapping relationship between tree shape parameters and vibration parameters was obtained. The results show that the 90% quantile of the acceleration of abscission of olives is 1113.35 m/s2; the average correlation coefficient between the simulation and the experiment results was 0.73, and the simulation was a good representation of the experimental results. When the tree shape was \"three open-center\", the trunk diameter and height were related to the vibration harvesting parameters; the average harvesting efficiency of olives was 91.22%, and the resonance frequency of the monitoring points was similar to that of the simulation results. This study provides a reference for the design of vibration harvesting equipment and fruit tree shaping.

The production of olive oil in Portugal and other countries of the Mediterranean region has greatly increased in recent years. Intensification efforts have focused on the growth of the planted area, but also on the increase of the orchards density and the implementation of irrigation systems. Concerns about possible negative impacts of modern olive orchard production have arisen in the last years, questioning the trade-offs between the production benefits and the environmental costs. Therefore, it is of great importance to review the research progress made regarding agronomic options that preserve ecosystem services in high-density irrigated olive orchards. In this literature review, a keywords-based search of academic databases was performed using, as primary keywords, irrigated olive orchards, high density/intensive/hedgerow olive orchards/groves, irrigation strategies, and soil management. Aside from 42 general databases, disseminated research, and concept-framing publications, 112 specific studies were retrieved. The olive orchards were classified as either traditional (TD) (50–200 trees ha−1), medium-density (MD) (201–400 trees ha−1), high-density (HD) (401–1500 trees ha−1), or super-high-density (SHD) orchards (1501–2500 trees ha−1). For olive crops, the ETc ranged from 0.65 to 0.70, and could fall as low as 0.45 in the summer without a significant decrease in oil productivity. Several studies have reported that intermediate irrigation levels linked with the adoption of deficit irrigation strategies, like regulated deficit irrigation (RDI) or partial rootzone drying (PRD), can be effective options. With irrigation, it is possible to implement agroecosystems with cover crops, non-tillage, and recycling of pruning residues. These practices reduce the soil erosion and nutrient leaching and improve the soil organic carbon by 2 to 3 t C ha−1 year−1. In this situation, in general, the biodiversity of plants and animals also increases. We expect that this work will provide a reference for research works and resource planning focused on the improvement of the productive and environmental performance of dense irrigated olive orchards, thereby contributing to the overall enhancement of the sustainability of these expanding agroecosystems.

This study investigated the maturity and optimal harvest interval of the ‘Kalinjot’ olive cultivar in the Vlora region. Fruit samples were collected from six randomly selected trees over nine harvest dates at 10-day intervals from September to December 2024. Physical, chemical, and instrumental analyses were conducted to evaluate parameters related to olive ripening and oil quality. Destructive methods measured the fruit diameter, fresh weight, maturity index, flesh firmness, and detachment index, while non-destructive techniques assessed the color and absorbance indices using portable Vis/NIR devices. Chemical analyses determined the fruit moisture, oil content, and total polyphenols. The results showed that the fruit diameter, fresh weight, and oil content increased with ripening, whereas the flesh firmness and detachment index decreased significantly. A negative correlation between the maturity index and color index was observed, along with strong positive correlations between the Kiwi-Meter’s IAD values, maturity index, and oil content. The optimal harvest interval was identified when olives reached up to 25.42% oil content and 1820.89 mg GAE/kg FW total polyphenols, ensuring both the technological and nutritional quality of the oil.