  Magnetic reconnection and particle acceleration due to the kink instability
in twisted coronal loops can be a viable scenario for confined solar flares.
Detailed investigation of this phenomenon requires reliable methods for
observational detection of magnetic twist in solar flares, which may not be
possible solely through extreme UV and soft X-ray thermal emission.
Polarisation of microwave emission in flaring loops can be used as one of the
detection criteria. The aim of this study is to investigate the effect of
magnetic twist in flaring coronal loops on the polarisation of gyro-synchrotron
microwave (GSMW) emission, and determine whether it could provide a means for
magnetic twist detection. We use time-dependent magnetohydrodynamic and
test-particle models developed using LARE3D and GCA codes to investigate
twisted coronal loops relaxing following the kink-instability. Synthetic GSMW
emission maps (I and V Stokes components) are calculated using GX simulator. It
is found that flaring twisted coronal loops produce GSMW radiation with a
gradient of circular polarisation across the loop. However, these patterns may
be visible only for a relatively short period of time due to fast magnetic
reconfiguration after the instability. Their visibility also depends on the
orientation and position of the loop on solar disk. Typically, it would be
difficult to see these characteristic polarisation pattern in a twisted loop
seen from the top (close to the centre of the solar disk), but easier in a
twisted loop seen from the side (i.e. observed very close to the limb).
