A new load and longer door opening increase cooling demand. A permitted rapid-cooling mode may also change the normal sound while it operates.
What the observation tells you
This explanation applies to the circumstances, not every loud sound. A metallic scrape or repeated failed start should not be dismissed as shopping-related. Check whether the mode is actually selected and whether packages block the intended air paths.
A useful next step
Let the appliance operate under its recommended conditions and monitor suitable storage. If the changed sound persists beyond the relevant mode or accompanies unreliable cooling, give the timing and loading details when requesting assessment.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.