Microfluidized emulsions

The samples (ca. 2500 g for each sample) were spray dried in a Niro Utility drier with the inlet temperature at 200 C and outlet at 100 C. The drier temperatures were allowed to stabilize before samples were collected for analysis. The dried samples were analyzed for total oil, surface oil, moisture, emulsion size and emulsion stability. Samples were also stored at an elevated temperature for shelf-life determination. Sensory analysis of rehydrated powder from the coarse and Microfluidized emulsions was performed to determine if differences in emulsion size affects the perceived flavor intensity. 

S. Okushima, T. Nisisako, T. Torii, and T. Higuchi Controlled Production of Monodisperse Double Emulsions by Two-Step Droplet Breakup in Microfluidic Devices. Langmuir 20, 9905 (2004). 

The dispersed droplet size, referred to as emulsion or particle size, can be reduced in the spray drier infeed matrix by more vigorous mixing or homogenization. There is also a new technique for creating small emulsions termed microfluidization which will be discussed later. This research was designed to determine whether the size of emulsion in the infeed solution will affect the characteristics of the final spray dried powder. Materials and Methods... 

Newton, MA). Microfluidization based on patented technology in which a split feed stream flows into an interaction chamber at ultrahigh velocities and pressures (up to 1500 ft and 16,000 psi respectively). The two streams collide head-on and exit the chamber at a right angle to the collision. The force of the collision creates cavitation and shear forces to decrease the particle size. The feed stream was prepared in a manner similar to the coarse emulsion in which the orange oil was blended into the carrier solution with a whisk. The Microfluidizer was operated at a pressure of 11,000 psi and the sample was collected after one pass through the interaction chamber. 

Sensory Analysis. A paired comparison test was run to determine if the difference in oil droplet size in the emulsion changed the perceived intensity of the orange flavor. The coarsest emulsion (3.87 pM) and the Microfluidized sample (0.90 pM) from the third set of spray dried samples were compared. The solutions were prepared using 200 ppm flavor in a 10% (w/v) sucrose solution with 0.30% of a 50% citric acid solution added. The amount of each powder required to attain 200 ppm orange oil was calculated on the basis of percent oil in each powder (determined by Clevenger analysis). A pair of samples at approximately 10 C was given to each of 24 untrained panelists. The samples were coded with random numbers. Half the panelists were asked to taste the coarsest sample first while while the other half tasted the Microfluidized sample first. This was done to determine whether or not adaptation was a factor. The panelists were asked to indicate which sample had the most intense orange flavor. 

Emulsion sizes determined only on first and third trials Microfluidized sample not prepared for first trial... 

McCrae, C.H. 1994. Homogenisation of milk emulsions use of microfluidizer. J. Soc. Dairy... 

Fig. 7 Emulsion droplet size versus number of passes through the microfluidizer for a 10% oily phase emulsion processed at 10,000 psi. (Adapted from Ref. l)...

Microfluidizer M-llOY (Microfluidics) Laboratory scale Pressure range Batch (>60ml) Dispersions, emulsions. 

Washington, C. Davis, S.S. The production of parenteral feeding emulsions by microfluidizer. Int. J. Pharm. 1988,... 

Dalgleish, D.G., Tosh, S.M., and West, S. (1996). Beyond homogenization The formation of very small emulsion droplets during the processing of milk by a microfluidizer. Neth. Milk Dairy J. 50,135-148. 

Lidgate DM, Fu RC, Fletiman JS. Using a microfluidizer to manufacture parenteral emulsions. 

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