Measurement of lipoxygenase in Australian white wheat flour: the effect of lipoxygenase on the quality properties of white salted noodles

The enzyme lipoxygenase has a number of functions in breadmaking. Although white salted noodles are a staple food in various countries, the significance and potential of lipoxygenase in noodlemaking are less well understood. In these products a bright, uniform appearance is particularly important and so the aim of the present research has been to study the effect of endogenous and exogenous lipoxygenase upon discolouration of white salted noodles as well as on the textural and structural attributes. Similar lipoxygenase levels were recorded in the flours studied and no significant losses of activity were found during noodle manufacture and subsequent storage. Less discolouration occurred in treated noodle sheets compared with control samples. Discolouration happened to a lesser extent when samples were cooked immediately after preparation or drying for both treated and control noodles. Whiter noodle sheets were obtained when a soybean lipoxygenase was added to the formulation. Textural and structural properties of white salted noodles were not adversely affected by enzyme addition, giving firm, elastic and non-sticky products. It is concluded that the incorporation of the lipoxygenase preparation offers prospects for colour enhancement of white salted noodles.