diff --git a/coffee_scale/mqtt.py b/coffee_scale/mqtt.py
index 97180d8..ee49cd7 100644
--- a/coffee_scale/mqtt.py
+++ b/coffee_scale/mqtt.py
@@ -17,7 +17,7 @@ def on_connect(client, userdata, flags, rc):
     client.subscribe('sik/kiltahuone/kahvivaaka/#')
 
 
-def on_message(client, userdata, msg):
+def update_latest(msg):
     payload = msg.payload.decode('utf-8')
     if msg.topic == TOPICS['WEIGHT']:
         weight = float(payload)
@@ -33,6 +33,13 @@ def on_message(client, userdata, msg):
         latest['brew_time'] = brew_time
 
 
+def on_message(client, userdata, msg):
+    try:
+        update_latest(msg)
+    except Exception as ex:
+        logging.exception('Failed to parse MQTT payload.')
+
+
 def on_disconnect(client, userdata, rc):
     if rc != 0:
         logging.warning('MQTT unexpectedly disconnected.')