A cost analysis of encapsulated spray-dried milk fat.
Anhydrous butter oil or cream was encapsulated in all-purpose flour, modified cornstarch, or sucrose and then spray-dried. We estimated the processing cost for a plant designed to produce 57,000 kg/d (125,000 lbs/ d) of encapsulated milk fat powder. Powder with a 50% milk fat content could be produced for about $0.23/kg plus the cost of the butter oil or cream, the encapsulant selected, and the other ingredients. Spray-drying of milk fat improved ease of handling and reduced storage costs.
Single droplet analysis for spray drying of foods
Many food ingredients, such as enzymes and probiotics, are spray dried to provide shelf-life. Major hurdle to apply spray drying is the lack of scientific insight on the inactivation mechanisms of components and the extensive optimization required for formulation and drying conditions to obtain powders of acceptable quality. This thesis reports on the development of an alternative approach to study drying behaviour involving single droplet experimentation in combination with predictive modelling. During single droplet drying, conditions such as drying air temperature, drying time, air flow rate, and particle size could be well controlled, which enabled systematic investigation of inactivation kinetics of heat sensitive components. Experiments were carried out with the heat sensitive enzyme (b-galactosidase) and the probiotic microorganism (Lactobacillus plantarum WCFS1). A novel viability enumeration method was developed to measure survival of probiotic bacteria, involving rehydration of (semi-) dried particles on a micro-porous chip in combination with fluorescence-based viability enumeration. The drying history of single droplets was modelled using an effective diffusion model. The diffusivity in this model was measured and modelled as function of moisture content and temperature on the basis of gravimetric analysis of thin film drying in a dynamic vapour sorption analyser (DVS). Subsequently, models were developed to describe inactivation kinetics as function of particle drying history. Finally, the obtained insight and approach were validated by comparison of predictions to results obtained during lab-scale spray drying experiments. Moreover, the single droplet approach can be used as a tool for screening optimal spray drying conditions
Metabolism of individual fatty acids by sheep depot adipose tissue in vivo and in vitro.
1. 
1. Sheep adipose tissue and plasma have high stearate and low unsaturated fatty acid content compared to rat, dog and man. 
 
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2. In control animals in vivo uptake as well as release of various fatty acids by adipose tissue could be demonstrated. In vitro net release occurred. Fasting resulted in a decrease in tissue stearate and increased release of fatty acids. Adrenaline and noradrenaline had minimal lipolytic effect in vivo and in vitro. 
 
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3. Variations in the turnover rate of individual fatty acids were observed.