COMPARING TRANS-FAT AND TRANS-FAT-FREE DOUGHNUT SHORTENINGS BASED ON SENSORY EVALUATION AND OIL DEGRADATION

This is an initiative study on the use of trans -fat-free products in the bakery industry. A standardized doughnut product was cooked in three doughnut shortenings, one containing trans fat and two that were trans fat-free. Six hundred forty-one panelists, students, faculty and staff of a large northeastern university rated each of the three doughnuts on a variety of categories, including texture, moisture content and overall liking. Results showed that there were no significant differences between doughnuts cooked in the three shortenings – this was true for all attributes tested.
The results from this study have many significant implications for the foodservice industry, as they work to cut down or eliminate the use of trans fats in their establishments because of the significant health risks they have been proven to cause.

PRACTICAL APPLICATIONS

This study demonstrates the variances on texture, taste, appearance and overall liking characteristics of doughnuts fried in different doughnut shortenings. The nutritional breakdown of the doughnuts and the shortenings are also addressed. In the case of shortenings, the ideal type of fat is a mixture of canola, soybean and hydrogenated cottonseed. This shortening mixture, which is trans fat-free, produced the most preferred doughnut.     

Glutamate Exocytosis and MARCKS Phosphorylation Are Enhanced by a Metabotropic Glutamate Receptor Coupled to a Protein Kinase C Synergistically Activated by Diacylglycerol and Arachidonic Acid

Abstract: 4-Aminopyridine evokes repetitive firing of synaptosomes and exocytosis of glutamate by inhibiting a dendrotoxin-sensitive K⁺ channel responsible for stabilizing the membrane potential. We have shown previously that activation of protein kinase C (PKC) by high concentrations of phorbol ester (4β-phorbol dibutyrate) can increase release by inhibiting a dendrotoxin-insensitive ion channel, whereas the metabotropic glutamate receptor (mGluR) agonist (1 S ,3 R )-1-aminocyclopentane-1,3-dicarboxylate [(1 S ,3 R )-ACPD] mimics the action of 4β-phorbol dibutyrate, but only in the presence of 2 µ M arachidonic acid (AA). In this article, we investigate the role of AA. AA plus (1 S ,3 R )-ACPD is without effect on KCl-induced glutamate exocytosis, indicating that the regulatory pathway acts upstream of the release-coupled Ca²⁺ channel or Ca²⁺-secretion coupling. Diacylglycerol concentrations are greatly enhanced by (1 S ,3 R )-ACPD alone, independently of AA, indicating that AA acts downstream of phospholipase C. Myristoylated alanine-rich C kinase substrate (MARCKS) is the major presynaptic substrate for PKC. mGluR activation by (1 S ,3 R )-ACPD enhances phosphorylation of MARCKS, but only in the presence of AA. These results strongly suggest that AA acts on presynaptic PKC synergistically with diacylglycerol generated by the phospholipase-coupled mGluR, consistent with the known behaviour of certain purified PKC isoforms. The magnitude of the effects observed in a population of rat cerebrocortical synaptosomes suggests that this is a major mechanism regulating the release of the brain's dominant excitatory neurotransmitter and supports the concept that AA, or a related compound with a similar locus of action, may in certain circumstances play a role in synaptic plasticity.     

Ontogeny of the Behavior of Strombus maculatus (Gastropoda: Strombidae)

The ontogeny of strombid behavior was studied by observing thebehavior of Strombus maculatus veligers collected from the planktonand reared past metamorphosis to adults, and by observing juvenilestrombids collected in the field. Complete adult modal actionpatterns (MAP's) associated with locomotion, feeding, and rightingof overturned shells are performed by S. maculatus juvenilesimmediately after metamorphosis. There are changes in the frequencyof the use of certain MAP's which are associated with variationsin shell shape and size. The unique strombid escape response to molluscivorous gastropods(Conns spp.) is not released until juvenile S. maculatus arethree weeks past metamorphosis and two millimeters in shelllength. At that stage, the complete response is released uponthe first encounter with a predator. Experience with a predatordoes not seem to lower the age or size criteria. During ontogeny there is a trend toward an increasing complexityof behavior which is paralleled by an increasing complexityof neural structure and general morphology. There are majorsteps in the ontogeny of strombid behavior which probably coincidewith neural and morphological stages.     

A Dynamic Growth Model of Vegetative Soya Bean Plants: Model Structure and Behaviour under Varying Root Temperature and Nitrogen Concentration

A differential equation model of vegetative growth of the soyabean plant (Glycine max (L.) Merrill cv. ‘Ransom’)was developed to account for plant growth in a phytotron systemunder variation of root temperature and nitrogen concentrationin nutrient solution. The model was tested by comparing modeloutputs with data from four different experiments. Model predictionsagreed fairly well with measured plant performance over a widerange of root temperatures and over a range of nitrogen concentrationsin nutrient solution between 0.5 and 10.0 mmol in the phytotron environment. Sensitivity analyses revealedthat the model was most sensitive to changes in parameters relatingto carbohydrate concentration in the plant and nitrogen uptakerate. Key words: Glycine max (L.) Merrill, dry matter, nitrogen uptake, partitioning, photosynthesis, respiration, sensitivity analysis     

Occurrence and Relatedness of Vancomycin-Resistant Enterococci in Animals, Humans, and the Environment in Different European Regions

Vancomycin-resistant enterococcci (VRE) in Europe are thought to have emerged partly due to the use of the glycopeptide avoparcin in animal husbandry. We compared the occurrence of VRE in geographical regions of Europe in which until 1997 large amounts of avoparcin were used (Spain, United Kingdom, and Denmark) with the occurrence of VRE in Sweden, where avoparcin was banned in 1986. We also studied the relatedness between VRE strains from different regions and habitats. In total, 2,580 samples were collected from humans, animals, and the environment (soil, sewage, recipient water). VRE resistant to 20 μg/ml vancomycin were identified in 8.2% of the samples and were found most frequently in raw and treated urban sewage samples (means, 71% and 36% of the samples, respectively), pig manure (17%), and hospital sewage (16%). The proportions of VRE-positive sewage samples were similar in Sweden, Spain, and the United Kingdom, whereas pig feces and manure were more often positive in Spain than in Sweden (30% versus 1%). Most VRE were Enterococcus faecium carrying vanA, and computerized biochemical phenotyping of the isolates of different ecological origins showed a high degree of polyclonality. In conclusion, it seems that animal-associated VRE probably reflect the former use of avoparcin in animal production, whereas VRE in human-associated samples may be a result of antibiotic use in hospitals. Since there seems to be a reservoir of the resistance genes in all countries studied, precautions must be taken to limit the use of antibiotics and antibiotic-like feed additives.