Influence of Fluidized Bed Jet Milling on Structural and Functional Properties of Normal Maize Starch

Abstract

Normal maize starch samples with moisture contents of 11.24%, 6.18%, and 1.5% are ground using a fluidized bed jet mill at classifier frequencies of 2400, 3000, 3600, and 4200 to produce micronized starch powder. The changes in structural and functional properties of the starch after jet milling process are studied. The particle size of starch significantly (p < 0.05) decreases after jet milling and as the classifier frequency increases. Also, the bulk and tap density decreases; while the specific surface area increases and the flowability of the milled samples becomes quite poor as the classifier frequency increases. The microscopy analysis shows that the jet milling destroys the crystalline areas and promotes amorphous areas of starch granules. The micronized starch samples show a significant (p < 0.05) increase in their water solubility, swelling power, water and fat holding capacities, and pasting temperature compared with native starch. However, a decrease in viscosity parameters of starch is found after jet milling and as classifier frequency increases. The initial moisture content of starch shows a slight effect on the functional properties of the micronized starch. The obtained results suggest that modified starch can be produced by fluidized bed jet milling.

Preparation of octenyl succinic anhydride‐modified cassava starch by the ultrasonic‐assisted method and its influence mechanism

“…After ultrasonic treatment for 1 min, the surfaces of some starch granules became rough and small fragments flaked off on the surfaces (Figure B). After ultrasonic treatment for 8 min, the free vibration amplitude of starch molecules improved and the surface activity of starch granules increased (Wang et al, ). Therefore, starch granules with higher surface activity tended to aggregate, so some bulges formed on the surfaces at this stage.…”

Relationship between sorption characteristic and selected functional properties of chemically modified waxy maize starches

“…Starch granules with low surface area exhibited higher swelling capability probably due to the presence of phosphate groups and absence of lipids on the granule surface. Wang et al () found that jet‐milling of normal maize starch led to the increase in mean weight specific area followed by the increase in pasting temperature caused by the destruction of starch, decrease in particle size and weaker intramolecular interactions of starch dispersed in water. On the contrary, it was established that amylose content had major influence on pasting temperature than granule size and phosphorus content using multiply linear regression analysis of 105 potato starch samples (Zaidul et al, ).…”

Fluidized Bed Jet Milling Process Optimized for Mass and Particle Size with a Fuzzy Logic Approach

“…The granular material is fed to the cylindrical grinding chamber (6) gravitationally from the charging container (8). The fed material undergoes extensive fluidization employing air jets from the nozzles (5). The nozzles inject air concentrically at a controlled flow rate and overpressure p with flow velocity u.…”

“…It depends on many parameters, such as different physical and chemical properties of the material being ground: homogeneity, strength, hardness, humidity, viscosity, forces and stresses occurring in said particles, internal particle structure, material defects of ground particles, and mill construction. A random occurrence often characterizes these variables [ 1 , 4 , 5 , 6 ].…”

“…On the basis of the experimental data, a simple Kapur’s model for batch grinding was applied. The authors in [ 5 ] described changes in the structural and functional properties of starch after the jet milling process. The results of jet milling efficiency of various inorganic materials (white sand, glass, iron oxide, hard coal, potassium and aluminum) with a narrow particle size distribution were considered in [ 6 ].…”