This paper presents a review of the industrially most relevant exudate gums: gum arabic, gum karya, and gum tragacanth. Exudate gums are obtained as the natural exudates of different tree species and exhibit unique properties in a wide variety of applications. This review covers the chemical structure, occurrence and production of the different gums. It also deals with the size and relative importance of the various players on the world market. Furthermore, it gives an overview of the main application fields of the different gums, both food and non-food.

Dairy phospho- and sphingolipids are gaining interest due to their nutritional and technological properties. A new HPLC method, using an evaporative laser light-scattering detector, was developed, which enabled excellent separation of glucosylceramide, lactosylceramide, phosphatidic acid, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine, sphingomyelin, and lysophosphatidylcholine in less than 21 min, including the regeneration of the column. No loss of column performance was observed after 1500 runs because an acid buffer was used. The output signal of the evaporative laser light scattering detector was highly dependent of the flow of the carrier gas and the temperature of the nebulizer, and was maximized by means of a response surface experimental design. Finally, raw milk, cream, butter, buttermilk, Cheddar whey, quarg, and Cheddar cheese were analyzed for their polar lipid content. The absolute values varied substantially (0.018 to 0.181 g/100 g of product). Significant differences were found in the relative content of each polar lipid class among the analyzed products.

To improve their overall flexibility and efficiency, many organisations have replaced traditional hierarchical management structures with empowered (semi-autonomous or self-managing) work teams. Managers, once charged with directing and controlling work, are now asked to take on a new set of roles and responsibilities in order to lead these teams (Lawler, 1992). Arnold and colleagues (2000) identified five categories of

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The influence of the refining process on the distribution of free and esterified phytosterols in corn, palm, and soybean oil was studied. Water degumming did not affect the phytosterol content or its composition. A slight increase in the content of free sterols was observed during acid degumming and bleaching due to acid-catalyzed hydrolysis of steryl esters. A significant reduction in the content of total sterols during neutralization was observed, which was attributed to a reduction in the free sterol fraction. Free sterols probably form micelles with soaps and are transferred into the soapstock. The steryl ester content remained constant during all neutralization experiments, indicating that hydrolysis of steryl esters did not take place during neutralization. During deodorization, free sterols are distilled from the oil, resulting in a gradual reduction in the total sterol content as a function of the deodorization temperature (220-260°C). A considerable increase in the steryl ester fraction was found during physical refining, probably owing to a heatpromoted esterification reaction between free sterols and FA.Paper no. J10068 in JAOCS 79, 947-953 (October 2002).