Ability of normal vaginal flora to produce detectable phosphatidylglycerol in amniotic fluid in vitro.

OBJECTIVE: To determine if bacteria are capable of producing phosphatidylglycerol in amniotic fluid (AF) and the number of colony forming units (CFU) of bacteria necessary to produce this result. METHODS: Eleven species of bacteria and one species of yeast, common to the female genital tract and implicated in chorioamnionitis, were selected. Amniotic fluid was collected from 21 women and inoculated with 10(8) CFU/mL of each isolate. Aliquots of AF were tested at 0, 4, 12, and 24 hours for colony counts and the presence of phosphatidylglycerol by thin-layer chromatography. RESULTS: The mean gestational age (+/- standard deviation) of the 21 study patients was 33 weeks and 1 day (+/- 4 weeks). Among the 12 species studied, Escherichia coli produced phosphatidylglycerol, at a concentration of 1.75 x 10(8) CFU/mL, beginning 12 hours after incubation. CONCLUSION: Escherichia coli is capable of producing phosphatidylglycerol in AF in vitro and is present in the vagina in 24% of normal pregnant patients. Our findings question the validity of using vaginal pool AF specimens for phosphatidylglycerol determination. Therefore, we recommend that patients presenting with preterm premature rupture of membranes be evaluated by amniocentesis to determine fetal lung maturity with phosphatidylglycerol and the lecithin-sphingomyelin ratio.

Assessment of oral malodor in dogs.

This paper describes a methodology for measuring and assessing changes in canine oral malodor with the intent that it can be used to evaluate products designed to make pets' breath more acceptable to their owners. Ten judges, able to discriminate and rank malodorous chemical compounds, were trained as a formal sensory panel by an expert in sensory evaluation techniques. The panel was assembled to determine changes in oral malodor resulting from dietary manipulation. A dry experimental food served as the test food, and a commercial dry dog food as the reference food. Dogs fed the experimental food developed significantly less oral malodor (p < 0.01) than when they were fed the control food.

Sensory and physical properties of a reduced-calorie frozen dessert system made with milk fat and sucrose substitutes.

Effects of milk fat and sucrose substitutes on selected physical and sensory properties of a frozen dessert system were evaluated by sensory and instrumental methods. Analysis of variance revealed no significant differences in textural attributes between sucrose and polydextrose-aspartame in freshly prepared frozen desserts and few differences after storage (140 d). Polydextroseaspartame effectively compensated for functional properties that normally are conferred by sucrose and some that are conferred by milk fat. Replacement of milk fat with tapioca dextrin or potato maltodextrin increased coarseness and wateriness and decreased creaminess relative to the control. Perception of chalkiness increased more with increased tapioca dextrin than with increased potato maltodextrin. Few or no significant differences among the frozen desserts were noted for the sensory attributes of coldness, gumminess, and mouth coating. Physical measurements did not relate highly to the sensory responses.

Macromolecule replacers in food products.

Traditional macromolecules and other recently synthesized materials have been accepted by consumers for use as low-calorie replacements for fats and sugars in food products. These include carbohydrates such as polydextrose, maltodextrins, modified starches, gums, and fibers. Protein and lipid-based replacements, including fat analogs and emulsifiers, are also available and some have been approved for use in food products. This article presents the properties of each of the macromolecule replacers, some uses that have been reported in food products, and speculative thoughts regarding functionality. Because control of water in the food product, added solids, and the mouthfeel characteristics associated with microparticles are three of the critical functions that must be provided by replacers, effectiveness of usage from a sensory perspective is also considered.

Comparison of aspartame- and fructose-sweetened layer cakes: importance of panels of users for evaluation of alternative sweeteners.

Panelists with and without known carbohydrate metabolic diseases evaluated layer cakes sweetened with aspartame, alone or in combination with low levels of fructose, for texture and flavor. Panelists used a 5-point, descriptive rating scale to evaluate flavor and texture of lemon, orange, spice, and chocolate layer cakes baked in conventional and microwave ovens. Panelists judged that aspartame alone was not suitable in layer cakes. In general, healthy panelists evaluated the cakes as sweeter, crust bitterness as greater, and overall eating quality as higher than the panel members with carbohydrate metabolic disorders. Panelists did not differ in their evaluation of textural qualities.