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The Australasian section of the American Oil Chemists Society (AAOCS) held their biennial meeting in Newcastle, Australia from 6 to 8 November, 2013. Over 150 scientists, researchers and industry representatives gathered for three days of talks and discussions on a variety of lipid related topics. The AAOCS awarded its inaugural AAOCS Award for Scientific Excellence in Lipid Research to Dr Allan Green from the Commonwealth Scientific and Industrial Research Organisation (CSIRO). Dr Green is deputy chief of the CSIRO Division of Plant Industry and has been active in lipid research for several decades. His main research focus is on plant breeding and genetic engineering techniques to develop improved oilseeds with enhanced human nutritional value and novel industrial uses. Refer to "AAOCS Award for Scientific Excellence in Lipid Research" for more detail of his contributions [1].

Orientador: Helena Teixeira Godoy Dissertação (mestrado) Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Um novo metodo rapido, eficiente e economico para a determinacao de cinco edulcorantes (acessulfame-K, sacarina sodica, ciclamato de sodio, aspartame e neotame) pela tecnica de cromatografia liquida de ultra performance (UPLC) foi desenvolvido, validado e aplicado na analise de alguns produtos diet, light e zero recorrentemente encontrados em supermercados. Para a otimizacao do metodo foi utilizado um delineamento composto central e a otimizacao simultanea de respostas foi realizada por meio da funcao de desejabilidade de Derringer e Suich. Foi empregada uma coluna de fase reversa C18, fase movel composta de acetonitrila e tampao fosfato de sodio 5 mM/ acido orto-fosforico (pH 3,0) com eluicao por gradiente e vazao de 0,4mL/min, com temperatura de coluna a 56oC. Os cinco compostos responderam linearmente em diferentes faixas de concentracao aplicaveis as concentracoes presentes nas amostras. A precisao intra e inter dias, bem como os limites de deteccao e quantificacao variaram para os cinco edulcorantes. As taxas de recuperacao para os edulcorantes avaliados variaram entre 70 e 115% para as diferentes matrizes analisadas. O metodo foi aplicado em refrigerantes, nectares e sucos, chas prontos para beber, pos para preparo de refresco, pudins e cappuccinos, achocolatados, geleias, catchup e molho tipo ¿barbecue¿. No entanto, algumas limitacoes foram encontradas para a quantificacao do neotame e ainda para alimentos contendo cacau em sua formulacao quanto a identificacao do ciclamato de sodio. Foram encontradas amostras contendo ate quatro edulcorantes em combinacao em um mesmo produto. Dentre os mais utilizados estavam o acessulfame e o aspartame. Algumas das amostras apresentaram ainda concentracoes acima das permitidas pela legislacao brasileira e, dentro dos edulcorantes estudados, nenhum edulcorante nao declarado foi encontrado. O metodo desenvolvido por UPLC foi comparado a uma metodologia por cromatografia liquida de alta eficiencia (HPLC). A UPLC apresentou melhor resolucao e menores limites de deteccao e quantificacao, tempo de analise mais curto e menor gasto de solvente. Entretanto, a HPLC ainda foi mais robusta Abstract: A new, fast, efficient and economic method for the determination of five sweeteners (acesulfame-K, saccharin, cyclamate, aspartame and neotame) by ultra performance liquid chromatography (UPLC) has been developed, validated and applied to diet, light and zero products usually found in supermarkets. A central composite design was used and also the simultaneous optimization of the answers was carried using the Derringer's desirability function for the method optimization. A C18 reversed phase column was used and the optimized method resulted in a binary eluent consisting of acetonitrile and sodium phosphate 5 mM/ ortophosphoric acid buffer (pH 3.0) in gradient elution, 0.4 mL/min flow rate and 56oC column temperature. The five compounds behaved linearly in different concentration ranges applicable to the concentrations in the samples and the precision intra and inter-day, as well as the limits varied for those sweeteners. The recoveries for the evaluated sweeteners varied for the distinct sample matrices from 70 to 115%. The method was applied to the sweeteners determination in soft drinks, fruit juice beverages, ready to drink teas, powder juice, pudding, cappuccino, chocolate powder, jellies, barbecue sauce and ketchup. However, limitations were found on the quantification of neotame and on the products containing cocoa, in which it is not possible to identify the sodium cyclamate. Samples containing up to four distinct sweeteners in synergism were found. Acesulfame and aspartame were the most used sweeteners among the analyzed samples. Although, non declared sweeteners were not found among those studied, their quantities in some samples were above the allowed in the Brazilian regulation. Afterwards, the UPLC developed method was compared with a high performance liquid chromatography (HPLC) method. The UPLC method presented the best resolution, the lowest detection and quantification limits, shortest retention time and lest solvent waste. However, HPLC is more rugged than UPLC Mestrado Engenharia de Alimentos Mestre em Ciência de Alimentos