Executives ... FYI.

Emulsifiers are known to promote fat destabilization during the freezing of ice cream and enhance the product's texture. However, no information has been available about the role that stabilizers play in fat destabilization.

Gums are commonly used in ice cream to improve feeling in the mouth by influencing water mobility. But their effect on fat agglomeration during the freezing process is unknown. Scientists attempted to study the effect of gum stabilizers on fat agglomeration during freezing in the presence and absence of emulsifiers. They added three different gums to an ice cream mix that had a composition of 10% milk fat, 10% milk solids-not-fat, 12% sucrose, 6% corn syrup solids and 0.15% mono-and diglycerides. Locust bean gum, carrageenan, and carboxy methyl cellulose were used either singly or in combination at concentration of 0.15%, except for carrageenan, which was added at 0.02%. Generally, there was less fat aggregation when the gums were combined with an emulsifier.

The results indicate that stabilizers in ice cream can affect fat agglomeration by somewhat modifying the casein and fat structure. This information is useful in understanding how stabilizers influence ice cream functionality.

There is substantial amount of evidence indicating that egg components may exert several diverse biological effects, above and beyond fulfilling basic nutritional requirements. The egg white contains a number of bio-active peptides, many which have biological functions associated with them.

For example, a vasorelaxing peptide, ovokinin (OA 358-365), was isolated by the peptic digestion of ovalbumin. Another peptide, ovokinin (OA 2-7) was found to possess vasorelaxing activity. Both peptides, when administered orally, significantly lowered the systolic blood pressure in spontaneously hypertensive rats. The phagocytic activity of macrophages was increased by adding OA 77-84 and OA 126-134 peptides, which were derived by the peptic and chymotryptic digestions of ovalbumin, respectively. Ovotransferrin is a monomeric glycoprotein, belonging to the transferrin family, a group of iron-binding proteins. A 92-amino acid ovotransferrin peptide, OTAP-92, was found to be capable of killing Gram-negative bacteria by crossing the bacterial outer membrane by self-promoted uptake, and damaging the cytoplasmic membrane. In addition, pronase-prepared glycopeptides of ovomucin have demonstrated anti-tumor effects in a double-grafted tumor system in mice. Ovomucin peptides may also act as immunomodulators, showing macrophage-stimulating activity in vitro. Functional phosphopeptides derived from phosvitin have exhibited enhanced calcium bioavailability.

Contact: James W. Harper, Department of Food Science and Technology, The Ohio State University, 2121 Fyffe Rd., Columbus, OH 43210. Phone: 614-292-7798. Fax: 614-292-0218. Email: harper.9@osu.edu.

Contact: Yoshinori Mine, Department of Food Science, University of Guelph, Building 038, Guelph, Ontario N1G 2W1, Canada. Phone: 519-824-4120. Fax: 519-824-6631. Email: ymine@uoguelph.ca.