Threshing wheat (Triticum aestivum L.) at high speeds is the main reason behind abnormal seedlings and vigor reduction of the seeds. This problem is expected to be severe in head‐stripper combines with successive impact loadings of stripping and threshing units. The aim of this study was to simulate the effects of impact velocities (IV), number of impact loadings (NL), and seed moisture content (MC) on percentage of physical damage (PPD) and percentage of loss in germination (PLG) to wheat seeds. Modeling the correlation between dependent and independent variables was performed using mathematical and artificial neural networks (ANN). The result showed that all the three independent variables significantly influenced PPD and PLG (P = 0.01). Increasing the IV from 5 to 30 m s−1 caused an increase in PPD and PLG from 0.17 to 35.8% and from 0.37 to 19.9%, respectively. It was found that the seeds with higher MC could better withstand physical and physiological damage than those with lower MC. With an increase in NL from 1 to 3 times, the mean values of PPD and PLG were increased by 2.9 and 2.6 times, respectively. An ANN model with two hidden layers, trained with a back‐propagation algorithm, successfully learned the relationship between the input and output variables. In comparison with regression models, ANN performed better when predicting PPD and PLG to wheat seeds.

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Introduction Mechanical damage of seeds due to harvest, handling and other process is an important factor that affects the quality of seeds. Objectives To evaluate the impact damage to navy bean seeds. Methods The study was conducted under laboratory conditions, using an impact damage assessment device. Independent variables were: seed moisture content (10, 12.5, 15, 17.5, 20, and 25% wet basis), impact velocity (5, 7.5, 10, 12.5, and 15 m/s) and seed orientation (side and end). Results Impact velocity, moisture content and seed orientation were all significant at the 1% level on the physical damage in seeds. Increasing the impact velocity from 5 to 15 m/s caused an increase in the mean values of damage from 0.17 to 32.88%. The mean values of physical damage decreased significantly by 1.96 times (from 27.09 to 13.79%), with increase in the moisture content from 10 to 15%. However, by a higher increase in the moisture from 15 to 25%, the mean value of damage showed a non-significant increasing trend. It was found that the relationship between beans mechanical damage with moisture content and velocity of impact was non-linear and the percentage damage to seeds was a quadratic function of moisture content and impact velocity, respectively. Impact to the end of the seeds produced the higher damage (20.61%) than side of the seeds (11.14%). Conclusion To minimize physical damage to navy bean seeds, the impact velocity should be limited to 10 m/s or below. The optimum level of moisture, where impact damage was minimized, was about 15%.

The main purpose of the current study was to propose innovative composite films based on a corn starch/polyvinyl alcohol (PVA) blend (starch:PVA 40:60) and loaded with 3 different levels of chitosan nanoparticles (CNPs) (1, 3, and 5% w/v) to strengthen its physical, mechanical, structural, thermal and antimicrobial attributes. The synthesized CNPs were spherical with a particle size of ca. 100 nm as demonstrated by scanning electron microscopy (SEM) micrographs and dynamic light scattering tests. The results showed that the CNPs incorporation within the starch-PVA 40:60 films promoted a uniform surface without any considerable pores. These films were characterized by a homogeneous CNP distribution within the polymer matrix, causing a significant decrease in water vapor permeability (WVP) (e.g., from 0.41 for the control film to 0.28 g.mm/kPa.h·m2 for the composite film loaded with 5% CNPs). The film solubility, transparency, glass transition and melting temperatures, and elongation at break were also reduced by increasing the CNP content from 1% to 5%, while total color and tensile strength parameters increased. The antibacterial effects of CNPs were more effective against Gram-positive bacteria (Staphylococcus aureus) than Gram-negative bacteria (Escherichia coli and Salmonella typhimurium). It can be concluded that the addition of CNPs to the starch-PVA matrix could improve its functional and technological attributes for food packaging applications.

The objective of this research was to evaluate and model the mechanical damage to corn seeds under impact loading. The experiments were conducted at moisture contents of 7.60 to 25% (wet basis) and at the impact energies of 0.1, 0.2 and 0.3 J, using an impact damage assessment device. The results showed that impact energy, moisture content, and the interaction effects of these two variables significantly influenced the percentage of physical damage in corn seeds (p<0.01). Increasing the impact of the energy from 0.1 to 0.3 J caused a significant increase in the mean values of damage from 23.73 to 83.49%. The mean values of physical damage decreased significantly by a factor of 1.92 (from 83.75 to 43.56%), with an increase in the moisture content from 7.6 to 20%. However, by a higher increase in the moisture from 20 to 25%, the mean value of damage showed a non-significant increasing trend. There was an optimum moisture level of about 17 to 20%, at which seed damage was minimized. An empirical model composed of seed moisture content and energy impact was developed for accurately describing the percentage of physical damage to corn seeds. It was found that the model has provided satisfactory results over the whole set of values for the dependent variable.

A b s t r a c t. The objective of this study was the evaluation of the aerodynamic properties of Makhobeli, triticale and wheat seeds as a function of moisture content from 7 to 27% (w.b). The results showed that the terminal velocity of triticale and wheat seeds increased linearly from 5.37 to 6.42 and from 6.31 to 8.02 m s -1 , respectively, as the moisture content increased from 7 to 27%. Over this same moisture content range, the terminal velocity of Makhobeli seeds varied following a polynomial relationship from 4.52 to 5.07 m s -1 . Makhobeli seeds had terminal velocities with a mean value of 4.73 m s -1 , at different moisture contents, compared to the mean values of 5.89 and 7.13 m s -1 for triticale and wheat seeds, respectively. The mean value of drag coefficient was 1.12 for Makhobeli compared to the values of 0.92 and 0.85 for triticale and wheat, respectively. The analysis of variance showed that there were significant differences between the terminal velocity (at 1% probability level) and drag coefficient (at 5% probability level) of Makhobeli with triticale and wheat seeds, which suggests that aerodynamic separation of Makhobeli from triticale and wheat is possible.K e y w o r d s: separation, post harvest operation, Makhobeli, weed control, triticale, wheat

Horticultural crops with the similar weight and uniform shape are in high demand in terms of marketing value that used as food. The knowledge on existing relationship among the mass, length, width, thickness, volume and projected areas of fruits is useful for proper design of grading machines. A part of this research was aimed to present some physical properties of cherry fruit. In addition, in this study the mass of cherry fruit was predicted with using different physical characteristics in four models including: Linear, Quadratic, S-curve, and Power. According to the results, all properties considered in the current study were found to be statistically significant at the 1% probability level. The best and the worst models for mass prediction of cherry fruit were based on geometric mean diameter and thickness of the cherry with determination coefficients (R 2) of 0.938 and 0.484, respectively. At last, mass model of cherry fruit based on first projected area from economical standpoint is recommended.

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