Effects of recombinant lipoxygenase on wheat flour, dough and bread properties

- The recombinant lipoxygenase (ana-rLOX) was first used in the breadmaking.
- Ana-rLOX addition improved the color of the wheat flour.
- Ana-rLOX addition improved the color and rheological properties of the dough.
- Ana-rLOX addition improved the textural and structural properties of the bread.

A purified recombinant lipoxygenase (ana-rLOX) was produced extracellularly in Bacillus subtilis and subsequently investigated for use in breadmaking. The variations in the properties of flour, dough and bread after treatment with the enzyme were studied. After adding ana-rLOX, whiteness (L*) of the wheat flour was improved and was similar to that achievable with the addition of benzoyl peroxide. For dough color, the L* of the ana-rLOX-treated sample was higher than that of benzoyl peroxide, and b* dropped sharply in the first 2.5 h after mixing with the flour. Also, the reinforcement or strengthening effect of wheat dough treated with ana-rLOX was determined by dough rheology and scanning electron microscopy of gluten matrix. The textural and structural quality parameters of the enzyme-treated bread showed improved properties including crumb color, specific volume, resilience, chewiness, and hardness. Compared with the control, the enzyme-treated bread volume improved 16.8%, the loaf height increased 10.3%, and the specific volume increased by 18.2%. This is the first report of the application of recombinant LOX in breadmaking, and the results provide a basis for future breadmaking bioprocess technology applications of ana-rLOX.