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ObjectiveTo quickly and accurately assess the situation of crop lodging disasters, it is necessary to promptly obtain information such as the location and area of the lodging occurrences. Currently, there are no corresponding technical standards for identifying crop lodging based on UAV remote sensing, which is not conducive to standardizing the process of obtaining UAV data and proposing solutions to problems. This study aims to explore the impact of different spatial resolution remote sensing images and feature optimization methods on the accuracy of identifying wheat lodging areas.MethodsDigital orthophoto images (DOM) and digital surface models (DSM) were collected by UAVs with high-resolution sensors at different flight altitudes after wheat lodging. The spatial resolutions of these image data were 1.05, 2.09, and 3.26 cm. A full feature set was constructed by extracting 5 spectral features, 2 height features, 5 vegetation indices, and 40 texture features from the pre-processed data. Then three feature selection methods, ReliefF algorithm, RF-RFE algorithm, and Boruta-Shap algorithm, were used to construct an optimized subset of features at different flight altitudes to select the best feature selection method. The ReliefF algorithm retains features with weights greater than 0.2 by setting a threshold of 0.2; the RF-RFE algorithm quantitatively evaluated the importance of each feature and introduces variables in descending order of importance to determine classification accuracy; the Boruta-Shap algorithm performed feature subset screening on the full feature set and labels a feature as green when its importance score was higher than that of the shaded feature, defining it as an important variable for model construction. Based on the above-mentioned feature subset, an object-oriented classification model on remote sensing images was conducted using eCognition9.0 software. Firstly, after several experiments, the feature parameters for multi-scale segmentation in the object-oriented classification were determined, namely a segmentation scale of 1, a shape factor of 0.1, and a tightness of 0.5. Three object-oriented supervised classification algorithms, support vector machine (SVM), random forest (RF), and K nearest neighbor (KNN), were selected to construct wheat lodging classification models. The Overall classification accuracy and Kappa coefficient were used to evaluate the accuracy of wheat lodging identification. By constructing a wheat lodging classification model, the appropriate classification strategy was clarified and a technical path for lodging classification was established. This technical path can be used for wheat lodging monitoring, providing a scientific basis for agricultural production and improving agricultural production efficiency.Results and DiscussionsThe results showed that increasing the altitude of the UAV to 90 m significantly improved flight efficiency of wheat lodging areas. In comparison to flying at 30 m for the same monitoring range, data acquisition time was reduced to approximately 1/6th, and the number of photos needed decreased from 62 to 6. In terms of classification accuracy, the overall classification effect of SVM is better than that of RF and KNN. Additionally, when the image spatial resolution varied from 1.05 to 3.26 cm, the full feature set and all three optimized feature subsets had the highest classification accuracy at a resolution of 1.05 cm, which was better than at resolutions of 2.09 and 3.26 cm. As the image spatial resolution decreased, the overall classification effect gradually deteriorated and the positioning accuracy decreased, resulting in poor spatial consistency of the classification results. Further research has found that the Boruta-Shap feature selection method can reduce data dimensionality and improve computational speed while maintaining high classification accuracy. Among the three tested spatial resolution conditions (1.05, 2.09, and 3.26 cm), the combination of SVM and Boruta-Shap algorithms demonstrated the highest overall classification accuracy. Specifically, the accuracy rates were 95.6%, 94.6%, and 93.9% for the respective spatial resolutions. These results highlighted the superior performance of this combination in accurately classifying the data and adapt to changes in spatial resolution. When the image resolution was 3.26 cm, the overall classification accuracy decreased by 1.81% and 0.75% compared to 1.05 and 2.09 cm; when the image resolution was 2.09 cm, the overall classification accuracy decreased by 1.06% compared to 1.05 cm, showing a relatively small difference in classification accuracy under different flight altitudes. The overall classification accuracy at an altitude of 90 m reached 95.6%, with Kappa coefficient of 0.914, meeting the requirements for classification accuracy.ConclusionsThe study shows that the object-oriented SVM classifier and the Boruta-Shap feature optimization algorithm have strong application extension advantages in identifying lodging areas in remote sensing images at multiple flight altitudes. These methods can achieve high-precision crop lodging area identification and reduce the influence of image spatial resolution on model stability. This helps to increase flight altitude, expand the monitoring range, improve UAV operation efficiency, and reduce flight costs. In practical applications, it is possible to strike a balance between classification accuracy and efficiency based on specific requirements and the actual scenario, thus providing guidance and support for the development of strategies for acquiring crop lodging information and evaluating wheat disasters.

为提高亚麻籽二酯油的稳定性和利用率，以抗性糊精和酪蛋白酸钠为复合壁材，单硬脂酸甘油酯（MG）和柠檬酸脂肪酸甘油酯(CITREM)为复合乳化剂，制备亚麻籽二酯油乳液，并进一步采用喷雾干燥法制备亚麻籽二酯油微胶囊。通过单因素实验考察固形物含量、MG与CITREM质量比、乳化剂添加量（以芯材质量计）和载油量对亚麻籽二酯油乳液粒径大小以及稳定性的影响，采用Box-Behnken设计响应面实验优化亚麻籽二酯油乳液的制备工艺，并采用钨丝灯扫描电子显微镜、傅里叶变换红外光谱仪、热重分析仪和体外模拟消化模型等对亚麻籽二酯油微胶囊的性质进行了分析。结果表明: 亚麻籽二酯油乳液最佳制备工艺条件为固形物含量50%、MG与CITREM质量比5∶ 4、乳化剂添加量2.5%、载油量50%，在此条件下亚麻籽二酯油乳液粒径为267.40 nm，亚麻籽二酯油微胶囊包埋率为97.85%; 亚麻籽二酯油微胶囊结构完整，整体呈球形，外部无明显损伤，且具有良好的热稳定性和溶解性；亚麻籽二酯油微胶囊在体外模拟胃肠道消化过程中芯材释放率达到84.59%。综上，微胶囊化有利于提高亚麻籽二酯油的稳定性，扩大其应用范围。 To improve the stability and utilization of linseed oil diglyceride, using resistant dextrin and sodium caseinate as composite wall materials, glycerol monostearate (MG) and citric acid fatty acid glyceride (CITREM) as composite emulsifiers, linseed oil diglyceride emulsion was prepared, and linseed oil diglyceride microcapsules were prepared by spray drying method.The effects of solid content, mass ratio of MG to CITREM, emulsifier dosage(based on core material mass) and oil load on the particle size and stability of linseed oil diglyceride emulsion were investigated by single factor experiment. Box-Behnken design response surface was used to optimize the preparation process of linseed oil diglyceride emulsion, the properties of linseed oil diglyceride microcapsules were analyzed by scanning electron microscope with tungsten filament lamp, Fourier transform infrared spectrometer, thermogravimetric analyzer and simulated digestion model in vitro.The results showed that the optimal preparation conditions of linseed oil diglyceride emulsion were obtained as follows:solid content 50%, mass ratio of MG to CITREM 5∶ 4, emulsifier dosage 2.5% and oil load 50%. Under these conditions, the particle size of linseed oil diglyceride emulsion was 267.40 nm, and the encapsulation rate of linseed oil diglyceride microcapsules was 97.85%. The linseed oil diglyceride microcapsules had complete structure, spherical shape, no obvious external damage, good thermal stability and solubility. The core material release rate of microcapsules in simulated gastrointestinal digestion in vitro reached 84.59%. In conclusion, microencapsulation is beneficial to improve the stability of linseed oil diglyceride and expand its application range.

甘油二酯（DAG）作为一种低热值的功能性脂质，因其特殊的理化性质和生理功能被广泛应用于食品体系中。为了考察DAG油作为煎炸油的可行性，以橄榄油基二酯油(ODO，82.3%)和橄榄油(OO，92.43%)煎炸薯条，对比研究两种油煎炸后的薯条在水分含量、质构、油含量、色泽、淀粉糊化度以及体外模拟消化淀粉水解率等方面的差异，并用扫描电子显微镜观察消化过程中薯条表面的微观形态变化,最后对两种油煎炸的薯条进行感官评价。结果表明： ODO煎炸薯条的水分含量（57.07%）、油含量（28.15%）、淀粉糊化度（90.7%）、体外模拟消化淀粉水解率（63.02%）分别高于OO煎炸薯条的水分含量（49.93%）、油含量（25.74%）、淀粉糊化度（88.3%）和体外模拟消化淀粉水解率（53.47%）；在质构和色泽上，与OO煎炸薯条相比，ODO煎炸薯条具有更高的脆度、更低的硬度及更好的色泽；从微观形态看，ODO煎炸薯条外表面淀粉颗粒的收缩、分散和变形更明显，经体外模拟消化后，OO和ODO煎炸薯条均发生了较大的细胞破裂，其中ODO煎炸薯条显微结构破坏更严重；OO和ODO煎炸薯条在口感、外观、风味、油腻性、脆度、硬度和整体接受度方面不存在显著差异。总体说来，ODO能够在一定程度上改善薯条品质，具有作为煎炸油的潜力。Diacylglycerol (DAG), as a functional lipid with low calorific value, is widely used in food system because of its special physicochemical properties and physiological functions. In order to investigate the feasibility of DAG oil as frying oil, French fries were fried with olive-based diacylglycerol oil (ODO,82.3%) and olive oil (OO,9243%), and the differences in moisture content, oil content, color, texture, starch gelatinization rate and starch hydrolysis rate in vitro simulated digestion of French fries were studied. In addition, the surface micromorphology changes of French fries during digestion were observed by scanning electron microscope (SEM). Finally, sensory evaluation of two kinds of French fries was carried out. The results showed that the moisture content (57.07%), oil content (28.15%), starch gelatinization rate (90.7%) and starch hydrolysis rate in vitro simulated digestion(63.02%) of French fries fried in ODO were higher than those in OO(49.93% moisture content, 25.74% oil content, 88.3% starch gelatinization rate, and 53.47% starch hydrolysis rate in vitro simulated digestion). As for color and texture, French fries fried in ODO possessed higher crispness, lower hardness and better color compared with that in OO. The microscopic morphology showed that the shrinkage, distraction and deformation of the starch granules on the outer surface of French fries fried in ODO were more obvious. After in vitro digestion, large cell rupture occurred in both OO and ODO French fries, and French fries fried in ODO had more serious damage to the microstructure. There were no obvious differences in mouthfeel, appearance, flavor, oilyness, crispness, hardness and overall acceptability between OO and ODO French fries. In general, ODO can improve the quality of French fries to a certain extent, so ODO has potential for application in frying.

旨在为山茶油的加工和储藏提供参考，采用Schaal烘箱法对4种工艺山茶油加速氧化，测定山茶油在储藏过程中酸值、过氧化值、p-茴香胺值、脂肪酸、甘油酯以及脂质伴随物的变化情况，并对山茶油质量指标与脂质伴随物进行Pearson相关性分析。结果表明：4种工艺山茶油在储藏过程中的酸值略微升高，上升为初始值的1.09~2.60倍；过氧化值、p-茴香胺值迅速上升，分别上升为初始值的10.31~16.49倍和3.06~4.43倍；α-生育酚含量大幅度下降，损失率为96.19%~100.00%，而角鲨烯、植物甾醇含量下降幅度不大，损失率分别为14.71%~51.79%和4.96%~19.49%，其中浸出-精炼山茶油的脂质伴随物含量最低，损失较多；由Pearson相关性分析可知，山茶油的质量指标（酸值、过氧化值、p-茴香胺值）与其α-生育酚含量呈显著或极显著负相关。综上，不同工艺山茶油的品质和营养价值在储藏过程中均明显下降，浸出-精炼山茶油的储藏稳定性不如压榨山茶油。In order to provide reference for the processing and storage of oil-tea camellia seed oil, the Schaal oven method was used to accelerate the oxidation of oil-tea camellia seed oil prepared with four processing techniques, and the changes of acid value, peroxide value, p-anisidine value, fatty acid, glyceride and lipid concomitants were measured. In addition, Pearson correlation analysis was performed on the quality indexes of oil-tea camellia seed oil and lipid concomitants. The results showed that the acid value of oil-tea camellia seed oil with different processing techniques increased slightly during the storage process, rising to 1.09-2.60 times of the initial value; while the peroxide value and p-anisidine value increased rapidly, rising to 10.31-16.49 times, 3.06-4.43 times of the initial value, respectively. At the same time, the content of α-tocopherol decreased significantly, with a loss rate of 96.19%-100.00%; while the content of squalene and phytosterol decreased slightly, with a loss rate of 14.71%-51.79% and 4.96%-19.49%, respectively. The lipid concomitants content of the leached-refined oil-tea camellia seed oil was the lowest with significant loss. In addition, the Pearson correlation analysis showed that the quality indexes (acid value, peroxide value and p-anisidine value) of oil-tea camellia seed oil were strongly negatively correlated with its α-tocopherol content. Overall, the quality and nutritional value of oil-tea camellia seed oil with different processing techniques decreased significantly during storage, and the storage stability of leached-refined oil-tea camellia seed oil was not as good as that of pressed oil-tea camellia seed oil.