The present work quantifies the impact of fuel chemistry on burning modes using premixed dimethyl ether (DME), ethanol (EtOH) and methane flames in a back-to-burnt opposed jet configuration. The study considers equivalence ratios 0 <= phi <= 1, resulting in a Damkohler (Da) number range 0.06 <= Da <= 5.1. Multi-scale turbulence (Re similar or equal to 19,550 and Re-t similar or equal to 360) is generated by means of a cross fractal grid and kept constant along with the enthalpy of the hot combustion products (T-HCP = 1700 K) of the counterflow stream. The mean turbulent rate of strain exceeds the laminar extinction rate for all flames. Simultaneous Mie scattering, OH-PLIF and PIV are used to identify reactants, mixing, weakly reacting, strongly reacting and product fluids. The relative balance between conventional flame propagation and auto-ignition based combustion is highlighted using suitably defined Da numbers and a more rapid transition towards self-sustained (e.g. flamelet type) combustion is observed for DME. The strain rate distribution on the reactant fluid surface for methane remains similar to the (non-reactive) mixing layer (Phi = 0), while DME and EtOH flames gradually detach from the stagnation plane with increasing Phi leading to stabilisation in regions with lower compressive rates of strain. The study further provides information on the conditions leading to burning mode transitions via (i) multi-fluid probabilities, (ii) structural flow field information and turbulence-flame interactions delineated by means of conditional (iii) velocity statistics and (iv) the rate of strain along fluid iso-contours. (C) 2020 The Combustion Institute. Published by Elsevier Inc. All rights reserved.