  We previously developed an automatic track scanning system which enables the
detection of large-angle nuclear fragments in the nuclear emulsion films of the
OPERA experiment. As a next step, we have investigated this system's track
recognition capability for large-angle minimum ionizing particles $(1.0 \leq
|tan \theta| \leq 3.5)$. This paper shows that, for such tracks, the system has
a detection efficiency of 95$\%$ or higher and reports the achieved angular
accuracy of the automatically recognized tracks. This technology is of general
purpose and will likely contribute not only to various analyses in the OPERA
experiment, but also to future experiments, e.g. on low-energy neutrino and
hadron interactions, or to future research on cosmic rays using nuclear
emulsions carried by balloons.
