Assessment of French bread texture by a multi-indentation test

• French bread texture is assessed by an original device based on multi-indentation.
• Crust and crumb properties can be distinguished by applying test on mini-breads.
• Baking time on jet impingement oven is ascertained by targeting crust properties.
• Specific bread recipe with fibres can be selected by ensuring crust/crumb contrast.

A specific equipment, made of an assembly of 10–20 vertical metal pins, has been implemented to assess the crusty texture of French breads by a so called multi-indentation test. It was connected to a force sensor set on a material testing machine in the range [0; 100 N]. The height of each pin was adjustable to the irregular surface of the crust of the tested specimen. Breads with varying texture were prepared under various dough mixing conditions and formats, different baking times (8, 11, 15 and 17 min), and with various contents of bioprocessed fibres. They were crushed, by the multi-indenter at a constant rate (50 mm/min), followed by a relaxation step while maintaining stable the final strain at 2/3rd of the initial sample height. Main variables measured from the resulting texture profile were related to crust stiffness and crumb firmness. The relevant bread format, accurate baking time and fibres content could be selected in function of given crust properties. Overall, the multi-indentation test proved a useful procedure to contribute to the design of breads with target texture.