Gouveia, José ManuelSantos, Maria José Abrantes dos2009-07-102009-07-102009http://hdl.handle.net/10400.5/1117Mestrado em Engenharia Alimentar - Tecnologia dos Produtos VegetaisThe aim of this work was to evaluate the stability of olive oil during six months of storage in stainless steel tanks (similar to those used in the mills). For this, six oil mill tanks were used, three with a normal atmosphere and three more with a modified atmosphere, with nitrogen, since the olive oil easily reacts with oxygen and suffers oxidative deterioration. The purpose was to determinate if olive oil stored in tanks with a non reactive atmosphere maintains its initial characteristics for a longer period of time. A Spanish variety was selected, Arbequina, that presents lower oxidation stability, relative to other olive oil varieties. Every month, different chemical analyses were performed: acidity, peroxide, index, spectrophotometry, tocopherols, polyphenols, oxidative stability and triacylglycerols oxidation. The olive oil stored with a normal atmosphere showed a slightly higher oxidative deterioration when compared with the olive oil stored in the tanks with a modified atmosphere, but no significant differences were found between the two different kinds of atmospheres except in triacylglycerols oxidation. In the sensorial analysis the oil mill tanks with a non reactive atmosphere presented a greater intensity in the “fruity”, “spicy” and “sweet” attributes, and also had a better final classificationporolive oilArbequinanitrogenstorage tanksoxidative deteriorationazeiteazotodepósitos de armazenamentooxidaçãomaster thesis