Distributions of Polycyclic Aromatic Hydrocarbons and Phthalic Acid Esters in Gums and Soapstocks Obtained from Soybean Oil Refinery

Soybean oil gums and soapstocks are important by-products that may potentially be contaminated by persistent organic pollutants (POP) such as polycyclic aromatic hydrocarbons (PAH) and phthalic acid esters (PAE), thus lowering the value when using them as starting materials to produce animal feed additives, food industry ingredients, and pharmaceutical products. In the present work, PAH and PAE distributions in these two types of by-products were detected using solvent extraction–solid phase extraction purification coupled with gas chromatography–mass spectrometry. Total PAH and PAE amounts in the soapstocks were significantly higher than those in the gums, thus indicating that neutralization showed much higher removal efficiency than degumming in terms of PAH and PAE eliminations. Meanwhile, the results proved that the concentrations of these two kinds of contaminants in the soybean oil gums and soapstocks were much higher than those in the soybean oils, suggesting that further investigations were needed and that the contents of PAH and PAE in soybean oil refining by-products should be carefully monitored and regulated.     

基于体积温度系数法测量进口精炼棕榈硬脂体积

为了估算拟卸液油到罐体积,使储油罐区有效配置罐容,避免加热液油卸入岸罐时发生溢冒事故,以进口精炼棕榈硬脂(熔点52.6℃)为例,研究了其在液态下温度变化和体积相对变化的关系,并基于体积温度系数对其在60～75℃范围内的体积进行了估算,同时实测液位和液温,求取体积和密度,计算液货质量,并采用常规密度推算法对精炼棕榈硬脂在60～75℃范围内的体积进行估算,对两种方法估算的体积进行t检验。结果表明：在60～75℃范围内,运用体积温度系数法求得的体积与常规密度推算法求得的体积没有显著差异。因此,可以采用体积温度系数法估算精炼棕榈硬脂的体积。     

The effects of oil,egg and salt content on some physical properties of canned moinmoin

Samples of canned moinmoin were prepared containing different quantities of oil, egg and salt. A uniaxial compression test was carried out on these samples using an Instron UTM. Three measurements were taken from the force-deformation traces, i.e. rupture force (F_R), deformation to rupture (D_R) and stress at yield point (Y_S). Variations in the oil content significantly influenced the values of F_R and D_R obtained. Variations in egg content influenced the values of F_R and Y_S. The salt content had no significant influence on the three measurements. The conclusions were that an increase in oil content softened the moinmoin whereas an increase in egg content resulted in a firmer product.     

Preparation of Docosahexaenoic Acid-Rich Diacylglycerol-Rich Oil by Lipase-Catalyzed Glycerolysis of Microbial Oil from Schizochytrium sp. in a Solvent-Free System

Docosahexaenoic acid (DHA)-rich diacylglycerol (DAG)-rich oil was prepared by lipase-catalyzed glycerolysis of microbial oil from Schizochytrium sp. in a solvent-free system. The reaction parameters including lipase type, substrate molar ratio, temperature, lipase concentration, and reaction time were screened. The selected conditions were determined as follows: Novozym® 435 (Novozymes A/S, Bagsvaerd, Denmark) as biocatalyst at 8 wt%, substrate ratio (DHA-rich microbial TAG/glycerol) of 1:1 mol/mol, temperature of 50 °C, and reaction time of 12 hours. Under these conditions, the triacylglycerol (TAG), DAG, and monoacylglycerol (MAG) contents in the product were 36.4%, 48.2%, and 15.4%, respectively. The lipase was reused successively for 18 cycles without significant loss of activity under the conditions given above. Fatty acid composition analysis of the final product showed that the contents of DHA in TAG, DAG, and MAG were 53.9%, 44.9%, and 34.8%, respectively. DHA-rich DAG has the potential to be used as an ingredient in infant formula to increase the bioavailability of DHA.     

A Comparative Study of Physicochemical and Flavor Characteristics of Chicken Nuggets during Air Frying and Deep Frying

Chicken nuggets were air-fried and deep-fried for various times at the same temperature. The moisture content, oil content, color, texture, volatile compounds, and lipids degradation of the chicken nuggets were investigated. The evolution rate of the moisture content, oil content, color, and texture were much higher during deep frying than during air frying. Air frying required more time to produce similar quality attributes as those of deep-fried chicken nuggets. On average, the oil content of the air-fried chicken nuggets was 25% lower than that of the deep-fried chicken nuggets. Of the 74 volatile compounds identified in the fried chicken nuggets, aldehydes, hydrocarbons, and heterocycles were the main flavor contributors. The total amount of volatile compounds and aldehydes detected in the air-fried chicken nuggets was much lower than that in the deep-fried samples, but the number of heterocycles produced by the Maillard reaction was higher during air frying. Sensory evaluation revealed that the air-fried chicken nuggets had lower oiliness and crispness, and 9 min was the optimal frying time to obtain air-fried chicken nuggets with similar sensory attributes (color, odor, juiciness, and overall acceptance) as those of the best deep-fried chicken nuggets. Air frying was a healthier frying method for the production of fried chicken nuggets, which could reduce oxidative degradation of lipids in chicken nuggets.     

Microwaves to control Callosobruchus maculatus in stored mung bean (Vigna radiata)

Disinfestation of stored grains using microwaves can be an alternative to chemical methods for controlling insects in grains and pulses. Mung bean of 12% moisture content (m.c.) was infested with different life stages of the cowpea weevil (Callosobruchus maculatus) and exposed to 200, 300 or 400 W microwave power levels for 14, 28 and 42 s. One hundred percent insect mortality for all life stages (egg, young larva, old larva, pupa and adult) was achieved with exposure to 400 W power level for 28 s, which caused a surface temperature of mung bean of 68.1 °C. Eggs were the most susceptible and adults were the least susceptible life stages to microwave treatments. No significant difference was observed between mortality of larvae and pupae stages and their mortality was between eggs and adults. Mung bean temperatures increased and germination decreased with increased power level or exposure time.     

Stable auto-tuning of hybrid adaptive fuzzy/neural controllers for nonlinear systems

In direct adaptive control, the adaptation mechanism attempts to adjust a parameterized nonlinear controller to approximate an ideal controller. In the indirect case, however, we approximate parts of the plant dynamics that are used by a feedback controller to cancel the system nonlinearities. In both cases, “approximators” such as linear mappings, polynomials, fuzzy systems, or neural networks can be used as either the parameterized nonlinear controller or identifier model. In this paper, we present an algorithm to tune the adaptation gain for a gradient-based hybrid update law used for a class of nonlinear continuous-time systems in both direct and indirect cases. In our proposed algorithm, the adaptation gain is obtained by minimizing the instantaneous control energy. Finally, we will demonstrate the performance of the algorithm via a wing rock regulation example.     

Detecting and measuring rings in banknote images

Various intelligent systems show a rapidly growing potential use of visual information processing technologies. This paper presents an example of employing visual information processing technologies for detecting and measuring rings in banknote images. The size of the rings is one of parameters used to inspect the banknote printing quality. The approach developed consists of two phases. In the first phase, based on histogram processing and data clustering, image areas containing rings are localized and edges of the rings are detected. Then, in the second phase, applying the hard and possibilistic spherical shell clustering to the extracted edge pixels the ring centre and radii are estimated. The experimental investigations performed have shown that even highly occluded rings are robustly detected. Several prototypes of the system developed have been installed in two banknote printing shops in Europe.     

草鱼鱼油微胶囊芯材释放条件及缓释特性研究

以草鱼鱼油为芯材,大豆分离蛋白和壳聚糖为壁材,采用超声辅助均质和喷雾干燥法制备鱼油微胶囊;应用Avrami’s公式对微胶囊在不同贮藏温度、相对湿度及光照强度下的芯材释放率进行拟合,并对释放动力学、释放速率常数和释放机制参数进行分析。结果表明,鱼油微胶囊芯材释放率拟合程度良好(R20.97),当贮藏温度4~50℃,相对湿度34%时,释放机制参数n1,说明鱼油微胶囊芯材释放动力学介于扩散限制动力学和一级释放动力学之间;当相对湿度54%~92%,光照强度0~10 000lx时,释放机制参数n1,鱼油微胶囊芯材释放动力学属于一级释放动力学,表明在低温、干燥和避光的条件下能更好地保存鱼油微胶囊。通过微胶囊在体外模拟消化道中的缓释行为发现,经270min,粒径从起始的15.82μm减小到2.98μm,释放率达80.6%,说明微胶囊在模拟消化道中有缓释行为。     

α-生育酚、γ-谷维素及植物甾醇在乙酸乙酯 介质中清除自由基相互作用研究

利用Bliss模型,研究不同含量复配的3种脂质伴随物α-生育酚、γ-谷维素和植物甾醇在乙酸乙酯非极性介质中清除DPPH自由基能力和相互作用类型,采用傅里叶变换红外光谱初步阐释相互作用机理。结果表明:3种脂质伴随物单独清除DPPH自由基能力强弱为α-生育酚γ-谷维素植物甾醇;3种脂质伴随物两两复配后清除DPPH自由基主要呈现拮抗作用。动力学研究发现,非极性介质复配体系清除DPPH自由基的反应速率快慢由体系中主抗氧化剂决定;采用傅里叶变换红外光谱仪检测复配脂质伴随物光谱,发现羟基右移,推测氢键的形成可能是导致3种脂质伴随物在乙酸乙酯中产生拮抗作用的原因。