Physical properties and compression loading behaviour of corn seed

Abstract

A b s t r a c t. The aim of this study was to acquire data on the physical properties and compression loading behaviour of seed of six corn hybrid varieties. The mean values of length, width, thickness, geometric diameter, surface area, porosity, single kernel mass, sphericity, bulk and true density, 1 000 kernel mass and coefficient of friction were studied at single level of corn seed moisture content. The calculated secant modulus of elasticity during compressive loading for dent corn was 0.995 times that of the semi-flint type; there were no significant differences in the value of this mechanical property between semi-flint and dent corn varieties. The linear model showed a decreasing tendency of secant modulus of elasticity for all hybrids as the moisture content of seeds increased.K e y w o r d s: corn, physical properties, secant modulus of elasticity INTRODUCTIONThe importance of corn processing industries is increasing. Recent concepts in corn marketing emphasise the identification of the specific, rigorous quality needs of individual users, and there is considerable interest in grain quality as an end-use value. Parameters useful in the evaluation and recognition of such specific values include, among others, the physical properties of corn kernels. These properties include the three perpendicular dimensions, which affect cleaning and grading processing, the kernel surface, which affects drying, sphericity and thousand kernels mass, which affect packaging of seed, bulk density (affecting storage capacity), true density (affecting vehicle load), porosity (aeration possibility, drying), coefficient of static friction (moving on inclined plane) and compression loading behaviour, which affects milling, extruding and flake preparation. Previous studies have described the physical properties of corn kernels. Coskun et al. (2006) determined sweet corn seed properties as a function of moisture content, while Karababa (2006) reported similar results on popcorn kernels; sweet corn kernel properties were reported by Karababa and Coskuner (2007) and those of dent corn by Esref and Nazmi (2007). The quality of corn kernels is not evaluated solely by the physical traits mentioned above. The behaviour of the corn kernel during compressive loading is one of its textual properties. The processing of corn for food and feed requires various types of mechanical treatment that depend on external forces. The main component of corn kernels is starch granules; these have a complex hierarchical structure consisting of polysaccharide macromolecules that are partially arranged in ordered conformations as single and double helices and entangled to form supra-and sub-molecular structures Gaytan-Martinez et al. (2006). Proteins form a matrix surrounding and embedding the starch granules. The endosperm of corn, which is horny and floury, is a complex mixture of starch granules and protein. The proportion of horny and floury endosperm in the kernel differs in different types of corn, the general classes of which are flint corn, dent ...

MLR and experimental testing for characterization and classification of damage resistance of maize hybrids based on mechanical properties

“…There were significant differences in the BR between the half‐dent and dent maize ( p < .01). The data for the averaged BR showed that the half‐dent hybrids had stronger damage resistance than the dent hybrids; this is in agreement with the study by Babić et al, who found that the secant modulus of elasticity for dent maize hybrids was 0.995 times that of half‐dent maize hybrids (Babić et al, ). The elastic modulus is a measure of a material's resistance to elastic deformation.…”

Some Moisture-Dependent Physical and Thermal Properties of Bambara Groundnut

“…They have reported physical and mechanical properties of seeds, nuts, kernels and fruits such as maize (BartPlange et al), arigo seeds (Davies, 2010), tef seed (Ozarslan), chick pea, wheat grains (Aydin, 2002) (Ixtaina et al, 2008), rice (Correa et al, 2007), raw and parboiled paddy (Reddy & Chakraverty, 2004), and hemp seeds (Sacilik et al, 2003; flaxseed (Singh et al, 2012) and corn seed (Babic et al, 2013). Despite these efforts little has been done on the physical properties of BBG seeds talkless of developing simple empirical models for the relationships between these aforementioned properties and moisture content that may cause significant change in their magnitude.…”

Compression loading behaviour of sunflower seeds and kernels

“…Many researchers have studied the mechanical properties of various agricultural materials such as corn seed (Babic et al, 2013), soybean (Bargale et al, 1999), white sesame seed (Darvishi, 2012), and maize (Barnwal et al, 2012). Joshi (1993) observed that the force required to initiate seed coat rupture of pumpkin seed increased as moisture content increased from 5.1 to 10.5% d.b., beyond which it steadily decreased up to a moisture content of 21.7% d.b.…”