Executives ... FYI.

Starch lipid composites consist of a stable suspension of microscopic lipid droplets in a starch dispersion or gel. They have the outward appearance of the cooked starch product but incorporate valuable properties of the oil phase gel. The composites, when used in food products, do not impart undesirable flavor. On the contrary, they often impart a creamy flavor to dairy products.

Different amounts of the composites were used to replace milk solids in yogurt mixes. Researchers studied what effects the starch lipid composites would have on yogurt fermentation and rheology. The rate of fermentation was evaluated by the change of pH every two minutes during the fermentation of the yogurt. The investigators observed the syneresis of yogurt over three weeks of storage.

Yogurt mixed with milk solids and partially replaced by starch lipid composites fermented at a similar rate, as did the yogurt without the milk solids replaced. The initial viscosity was higher for yogurt mixed with higher levels of the composites. The higher initial viscosity did not affect gel structure. Adding the composites above a level of 3% strengthened the gel and did not cause syneresis in yogurt samples stored for three weeks at 4 C.

Contact: Mukti Singh, USDA-ARS National Center for Agricultural Utilization Research, Room 2116, 1815 N. University St., Peoria, IL, 61604. Phone: 309-681-6357. Fax: 309-681-6685. Email: mukti.singh@ars.usda.gov.

Extracts of plants, particularly herbs and spices, are rich in essential oil and secondary metabolites and possess antimicrobial activity as well. Some of these extracts are classified as GRAS. Because of consumer interest in natural products, a food-grade botanical ingredient with antioxidant properties would be a preferred choice for hurdle technology.

Scientists have developed a GRAS-based oregano and cranberry water extract for inhibiting L. monocytogenes. Five concentrations of phenolic compounds were optimized from oregano and cranberry extracts. These were evaluated for their antimicrobial activity in certain products, including chicken, beef and seafood. The growth of L. monocytogenes was effectively inhibited when the phenolic content of mixed oregano and cranberry extracts reached 0.1 mg of phenolic per ml. Their efficacy was enhanced by adding lactic acid, which is also GRAS.

Contact: Ronald Labbe, Department of Food Science, University of Massachusetts, Amherst, Chenoweth Laboratory, Room 342, Box 31410, Amherst, MA 01003. Phone: 413-545-1021. Fax: 413-545-1262. Email: rlabbe@foodsci.umass.edu.