کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
223679 | 464393 | 2011 | 10 صفحه PDF | دانلود رایگان |
This study investigated the diffusion of peanut oil and counter-diffusion of cocoa butter when cylindrical tempered or untempered samples, composed of cocoa butter with or without addition of cocoa powder, were suspended in peanut oil and stored at 23 °C. Oil migration kinetics was monitored using a novel pipette technique while diffusion and counter-diffusion were measured using gas chromatography. Tempering significantly lowered (p < 0.05) the peanut oil diffusion in the samples but did not influence the counter-diffusion of cocoa butter in peanut oil. Addition of cocoa powder at a volume fraction of 0.45 significantly increased (p < 0.05) peanut oil diffusion and decreased counter-diffusion. Due to the ingress of peanut oil, the solid fat content of tempered and untempered cocoa butter samples dropped from 75% to 59% after 7 weeks and resulted in corresponding dimensional changes in the samples which were also measured using image analysis. Diffusion, counter-diffusion and lipid phase changes were combined to develop a mass balance model to predict the volume changes occurring during oil migration.
Journal: Journal of Food Engineering - Volume 104, Issue 2, May 2011, Pages 186–195