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R Ginn

Publications and source records attributed to R Ginn.

6 recordsLinked to original sources

The effect of azodicarbonamide concentrations on ethyl carbamate concentrations in bread and toast.

A series of baking experiments have been undertaken in order to test the proposition that the use of the flour improver azodicarbonamide influences ethyl carbamate concentrations in baked bread. Samples were prepared in a laboratory and contained 0, 20 and 45 mg azodicarbonamide/kg; 20 mg/kg reflecting normal commercial usage and 45 mg/kg the UK statutory limit. Samples incorporating 0 and 20 mg/kg of the additive were also prepared in a commercial bakery. Toast made from these breads was examined since it is known that toasting can lead to increased ethyl carbamate concentrations. Statistical analysis of the data indicated that, at 45 mg/kg, azodicarbonamide led to significant increases in ethyl carbamate concentrations in both bread and the toasts made from it. At 20 mg/kg some small increases in ethyl carbamate were seen for bread and this approached statistical significance for those samples made in the commercial plant. When these breads were toasted an increase in ethyl carbamate was observed but this was not attributable to the use of azodicarbonamide.

Azo Compounds

The contribution of azodicarbonamide to ethyl carbamate formation in bread and beer.

Data on ethyl carbamate concentrations in beers purchased and analysed between 1988 and 1990 are presented. The concentrations in draught beers were uniformly below the detection limit of 1 microgram/l. Canned beers contained rather more ethyl carbamate (up to 2.5 micrograms/l) which is considered to be due to their longer shelf-life and higher alcohol content (in some cases). Bottled beers contained even higher amounts of ethyl carbamate (up to 14.7 micrograms/l) and this was considered to be due to the use of azodicarbonamide as a blowing agent in the beer bottle cap liners. It is understood that modifications to the liner have led to reduced concentrations in bottled beers produced more recently. A survey of bread samples and related cereal products such as rusks, French toasts and pitta bread indicated typical ethyl carbamate concentrations between < 0.4 and 4.5 micrograms/kg. Toasting bread led to increases of between three- and eight-fold in ethyl carbamate concentrations ranging from 3.5 to 33.8 micrograms/kg on a wet weight basis. Analysis of the data indicated that commercial bread samples which indicated the use of azodicarbonamide as a flour improver showed statistically significant increases in ethyl carbamate concentrations. The mean increase for treated bread over untreated bread was 66%. When these breads were toasted, the mean increase for treated toast over untreated toast was 56%.

Azo Compounds

Evaluating a computer-based experiential learning simulation: a case study using criterion-referenced testing.

A case study of a computer-based experiential learning program involving the use of criterion-referenced testing as a quantitative evaluation tool is described. The simulation was designed to introduce nurses to basic computer operations. One hundred and thirty-eight nurses participated in the evaluation using a specially prepared version of the program that recorded the time required to perform actions, the number of unsuccessful attempts to complete instructions, and the number of correct responses to specific questions. The ability of the nurses to "drag and drop" increased significantly from less than 20% to more than 90% (p < .05, Student's t-test). Their knowledge of the definitions of four computer-related terms (i.e., trackball, desktop, window, and icon) increased significantly (from 65% to 80%, p < .1). In subjective evaluations, 82% of respondents reported that they enjoyed the lesson and 89% wanted more computer-based instructional units to be developed. Use of criterion-referenced testing helped to shed new light on the utility of such computer aided instructional systems.

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