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This thesis describes the first randomized controlled trial on the ketogenic diet as a treatment for children with drug-resistant epilepsy. It asks two main questions. Firstly, are there clear benefits on seizure control in children treated with the ketogenic diet as compared with no additional treatment and secondly, is the classical ketogenic diet more efficacious than the medium chain triglyceride (MCT) ketogenic diet, as often claimed but not supported by scientific evidence The trial also examines the tolerability of the two diets, and their effect on growth. 145 children were randomized to receive the classical or MCT diet, either immediately or after a 3-month delay with no change in treatment (control group). Seizure frequency was assessed after 3 months, compared to that of controls. Efficacy and tolerability of the two diets was compared at 3, 6 and 12 months. Growth was assessed during the study period. Clear guidelines on calculation of both diets were developed, as was an electronic ketogenic calculator to reduce the burden of time spent on recipe calculations. Results show children on a ketogenic diet to have significantly reduced numbers of seizures after 3 months, as compared to the control group. Despite increased ketone levels in classical diet children, there was no difference in efficacy between the two diets at 3, 6 or 12 months. There was no difference in gastro-intestinal tolerability both diets caused increased cholesterol levels, but increased triglyceride levels were seen in the classical group only. Many children did show compromised growth during the study, but after 12 months, there was no significant difference in growth outcome between the two diets. These results strongly support using the ketogenic diet in childhood epilepsy. Classical and MCT diets are comparable in efficacy, tolerability and growth outcomes both protocols continue to have their place in the treatment of this group of children.

The objective of these studies was to determine: the impact of extended periods of frozen storage duration and packaging type on palatability traits of cooked beef steaks from two muscles and the impact of freezing type and storage duration on objective and subjective measures of ground beef palatability traits. In study 1, no differences were elicited from any of the possible interactions (P= 0.95) for SSF or CL: package × muscle × freezing duration, package × muscle, package × duration or muscle × duration. However, freezing duration did impact both SSF (P < 0.01) and CL (P < 0.001). Generally, for both SSF and CL steaks that were frozen for 9-months elicited both the highest SSF values as well as the greatest percentage of CL among all treatments. In comparison, EM was impacted by the interaction (P = 0.059) of packaging type  muscle  freezing duration. Samples from OW GM stored for 9-months elicited the highest percentage of EM while fresh OW LL samples resulted in the lowest. Additionally, expressible moisture was impacted by the interaction (P = 0.047) of muscle  freezing duration. Among all treatments, GM steaks that were frozen for 9-months elicited the highest EM values and fresh LL samples the lowest EM values. Contrastingly, there was no significant difference observed in expressible moisture for the interaction (P  0.18) of package type  freezing duration or for the interaction (P = 0.70) of package type  muscle. Generally, fresh OW GM steaks resulted in the greatest concentration of lipid derived volatile compounds such as aldehydes, hydrocarbons and alcohols which contrasted sensory ratings of trained panelists that indicated oxidized and refrigerator-stale ratings increased as storage time increased for OW steaks. In study 2, The interaction of freezer treatment × storage duration impacted gumminess (P = 0.05), a TPA attribute. In greater detail, samples stored in RF for 6-months resulted in the greatest gumminess values (P < 0.001), while those stored in the CF for 12-months elicited the lowest (P < 0.001). Similarly, flavor development was also impacted by the interaction (P = 0.05) of freezer treatment × storage duration. Three lipid derived compounds were of greatest concentration among RF patties stored for 1-month. In contrast, the interaction of freezer treatment × storage duration elicited no impact on consumer ratings, SF or TBARS. Nonetheless, frozen storage duration impacted TPA, flavor development, consumer ratings, SF and TBARS as a main effect (P < 0.05), especially in regard to tenderness and juiciness. Moreover, beef flavor development, tenderness and juiciness are impacted by freezing duration, muscle, freezer type and packaging, however these factors are not necessarily independent of one another. Furthermore, the retail display period is a critical period for fresh beef steaks, especially when packaged in aerobic conditions. For optimal eating experience, beef products should be stored for extended periods in a vacuum packaging, in a designated freezer that is not opened frequently to allow for optimal air flow regulation and minimize freezer burn to improve tenderness and juiciness.