Engineering in Agriculture, Environment and Food最新文献

The phosphine flow during fumigation of wheat in a Chinese horizontal warehouse is studied by computational fluid dynamics modeling. The Renormalization Group k-ε turbulence model is adopted to simulate the three-dimensional airflow field and the species transport model is used to calculate the species mixing. The phosphine concentrations in the warehouse with different leaky area positions during the fan-forced fumigation and the tablet fumigation are continuously predicted for 28.5 days. Also, the effects of the fumigation methods and the leaky area positions on the phosphine concentrations are discussed. The results reveal that the phosphine concentration in the tablet fumigation takes longer time to be uniform than that in the fan-forced fumigation. The maximum value of the phosphine concentration in the fan-forced fumigation is larger and appears earlier than that in the tablet fumigation. We also found that the fumigation methods have greater impact on the phosphine concentration than the leaky area positions in this study. And the impacts of the leaky area positions on the phosphine concentration could be further influenced by the fumigation methods.

Hatching window and the gender of hatching eggs were investigated in relation to the yolk content and yolk ratio (yolk to egg ratio) of the eggs. To quantify the amount of yolk noninvasively, a regression model from absorbance spectra (600–900 nm) was developed using known yolk content. This model was then used to determine the yolk content subsequently the yolk to albumen ratio of the hatching eggs. This yolk information of hatching egg was then correlated with hatching time and the gender of the egg. The results showed a significant correlation between estimated yolk-albumen ratio and hatching time, but no significant correlations were obtained with the gender of the eggs.

Accurate grain and food moisture content (mc) estimation is an issue of great economic importance in agro-food industry operations such as drying, storage, and processing. Nonetheless, there is a high level of unmet need for on-line mc sensing that could lead to more reliable grain processing automation. Dielectric models that relate product mc to its relative permittivity ε′ and loss factor ε" are considered promising solutions for continuous measurement of moisture in grain. The object of this paper was to investigate the applicability of three dielectric models derived from the function [(ε' – 1)/ε"] for mc measurement of sorghum from 7 to 23% w.b. Of the three dielectric models tested, the most satisfactory was the function [(ε′-1)/ε"]/[(2√ε′)/(1+√ε′)] at 0.1 and 1.0 MHz. However, the moisture range had to be divided into two intervals. The corresponding equations could estimate sorghum mc with standard errors of calibration of 0.6 and 0.7, and standard errors of prediction of 0.6 and 0.8 percentage point moisture, for calibration and validation sets respectively. Comparison of the results obtained here with those reported in literature revealed that the function [(ε′-1)/ε"]/[(2√ε′)/(1+√ε′)] produced mc values which are well within the performance of commercial moisture meters.

Plum (Japanese Apricot) having various economic importances, has been mainly processed for valuable products from its fleshes. To obtain plum flesh, seed removing is necessary but serious obstacle is to remove seeds. Therefore, an automatic plum seed remover (APSR) was identified, designed, manufactured and evaluated. The introduced APSR was comprised with an automatic plum supplying unit, plum positioning unit, punching and cutting unit, discharging unit, and controlling unit. The cutting unit was equipped with zero, two, or four blade cutters. The performance parameters of the APSR were assessed including in terms of flesh recovery, seed breakage, deseeding efficiency, and machine efficiency. In order to the performance evaluation of APSR, experiments were conducted at different conditions based on positioning competency on both fresh and frozen plums. The APSR was exhibited the better results comparing with Japanese and traditional plum seed remover. The test results of the developed machine showed 100% deseeding efficiency for ripe and hard plums. The capacity of APSR was 80 kg h⁻¹ without seed breakage. Flesh amount of plums were significantly different between four and zero blade cutters with positioning angles nearly, 0°, 15° and 180°. The developed APSR was recorded 87.90% flesh recovery for ripe plums and 83.02% flesh recovery for hard plums, respectively. APSR is preferred, because of its minimal flesh loss, rapid operation, increased productivity, low seed breakage and low labor expenditure. Hence, this APSR will take in advanced plum technology and be useful to flourish the plum industry for post-harvest processing of plum seeds.

Biofilm formation in processing equipment can lead to higher costs due to more frequent cleaning events as well as the contamination of processed foods and is a concerning issue. It is necessary to establish new methods for the detection of biofilms formation on surfaces. The use of electrochemical microsensors for biofilm detection could be a strategy for real time biofilm control in processing equipment. In this study, voltammetric methods, cyclic voltammetry (CV) and square wave voltammetry (SWV), were employed to detect P. polymyxa biofilms and CIP cleaning solutions on platinum-based interdigitated ring array microelectrodes. The differences between the current responses of the uncovered sterile microelectrodes and the microelectrodes after Paenibacillus polymyxa attachment for 18 h were determined. The surface coverage of microelectrodes was visualized using microscopy techniques. The results of this study demonstrated that cyclic voltammetry revealed the most promising results for P. polymyxa biofilm detection, while square wave voltammetry can be recommended for the detection of CIP cleaning solutions.

The objective of this study was to develop a generator-powered self-propelled automatic tray loading/unloading machine for rice seedling nurseries by using a gantry as the transport system to automate seedling tray placement and harvesting. During input operations, seedling trays are transported by conveyor belts to the nursery, and the tray loading/unloading machine automatically places the trays in rows in the nursery. During output operations, the tray loading/unloading machine automatically gathers the seedling trays from the nursery and transports them on conveyor belts to an automatic seedling mat roller. The entire system comprises mechanical components that achieve high operational stability and few malfunctions. Using a programmable logic controller for automation can effectively alleviate the inconvenience of laying heavy power cables. The tray loading/unloading machine automatically moves along the trusses of the gantry transport system, placing seedling trays in rows in the nursery. Alternatively, it can reverse directions and gather seedling trays from the nursery and transport them to the conveyor belts. The tray unloading capacity is 741 trays per hour, and tray loading capacity is 763 trays per hour. The tray loading/unloading machine enhances the automation operation of rice seedling nursery and alleviates the difficulty in hiring workers in farming villages where there are a shortage of labor.

This paper describes an applied research established in response to farmer's request for improvement of performance of tractor-implement in tillage operations. An effort for decrement of variations in plowing depth as well as increment of tractive efficiency of a moderate power tractor in tillage operations with mounted implements led to development of a fuzzy depth and draft control system for tractor-implement. The fuzzy control system consisted of an electrical sensing, control, and electro-hydraulic actuator unit. A command set including four fuzzy rules were programmed for the control unit. To determine merits of the fuzzy control system, the field experiments were carried out at three levels of plowing depth (10, 20 and 30 cm), forward speed (2, 4 and 6 km/h), and implement types (moldboard, disk, and chisel plow) utilizing the system mounted on a tractor (MF-399). Some performance parameters of tractor-implement were then determined in the field experiments. The results indicated application of the fuzzy control system rather than available draft control system of the tractor resulted in increment of tractive efficiency and overall energy efficiency up to 20 and 73%, respectively. Meanwhile, plowing depth error, driving wheel slip, and fuel consumption decreased up to 53, 34 and 34%, respectively. The performance of the fuzzy control system was not sensitive to implement type and plowing depth, while it was influenced by forward speed (P ≤ 0.01). The fuzzy control system adequately improved performance of tractor-implement in tillage operations and satisfied farmer's requirements. Hence, it is recommended to industrialize and commercialize the fuzzy control system in order to mount it on any moderate power tractor.

The purpose of this study was to develop extruded snack products using a blend of rice flour, corn flour and deoiled rice bran. Effects of feed moisture (12%–18%), barrel temperature (86^⁰C-154 °C) and screw speed (116–284 rpm) on the product properties like lateral expansion (LE), bulk density (BD), water absorption index (WAI), water solubility index (WSI) and hardness (H) were investigated. All these physical properties of extruded snacks were found to be significantly affected by changes in moisture, temperature and screw speed. The regression models for product responses like lateral expansion, bulk density, water absorption index, water solubility index and hardness were highly significant (p ≤ 0.001). The optimized extruded product was obtained at moisture content of 13%, barrel temperature 140 °C, and 203 rpm of screw speed. It was revealed that deoiled rice bran can be incorporated to produce snack products with desirable quality characteristics.

Aiming at the issue that it is easy to cause visual fatigue to count the quantity of milk somatic cells by microscope artificially, this paper raised automatic detection methods of counting milk somatic cells. To improve the quality of milk somatic cell's image, filtering and strengthening images with the method of DFT (Discrete Fourier Transformation). In order to increase the accuracy and speed of segmentation for somatic cell of milk images, and adjust the rapid testing requirement, it came up with the optimal threshold of image segmentation method based on niching particle swarm optimization Otsu(maximum class square error method). This method overcame the disadvantage of easily trapping in local solution and low rate in later convergence, improved the global optimization ability of the algorithmic. Using niche particle swarm optimization to optimize fitness function, it got the best segmentation threshold of Otsu, which could be used for image segmentation. At last, this paper provided handling methods for cell overlap and adhesion, through segmentation experiments using three different kinds of images of dyed milk somatic cell. Experiments showed that the methods raised in this paper are workable.

Sugar industry wastewater has the complex characteristic. Wastewater from the sugar industry, if discharged without treatment, poses pollution problems in both aquatic and terrestrial ecosystems. An attempted has been made to treat the sugar industry wastewater in an economical way with a combination of thermal and chemical treatment by aluminium salt. Results showed thermal treatment of sugar industry wastewater were 72% COD and 74% color removal at optimum pH 4.5, working temperature 85 °C, catalyst mass loading 5 kg/m³ and treatment time 9 hrs. The treated wastewater again treated with commercial alum shows 98% COD and 99.9% color removal at pH 6.5 and mass loading 6 mM. The filterability results show combined treated wastewater having 3.64 kg/m³ cake resistance and 5.26 × 10⁻¹² medium resistance. Nearly 80% of supernatant settling was achieved at 40 min of settling time. Overall combined treatment was found to be more suitable to treat sugar industry wastewater up to the dischargeable limit.