diff --git a/v2/blob/kalman_blob.go b/v2/blob/kalman_blob.go
index 6cb579d..6b8da8f 100644
--- a/v2/blob/kalman_blob.go
+++ b/v2/blob/kalman_blob.go
@@ -66,6 +66,7 @@ func NewKalmanBlobie(rect image.Rectangle, options *BlobOptions) Blobie {
 		yMatrix:             mat.NewDense(2, 1, []float64{centerX, centerY}),
 		uMatrix:             mat.NewDense(4, 1, []float64{0.0, 0.0, 0.0, 0.0}),
 		crossedLine:         false,
+		customProperties:    make(map[string]interface{}),
 	}
 	kalmanBlobie.pointTracker.SetStateValue(centerX, centerY, 0, 0)
 	if options != nil {
diff --git a/v2/blob/simple_blob.go b/v2/blob/simple_blob.go
index 42a4017..7332379 100644
--- a/v2/blob/simple_blob.go
+++ b/v2/blob/simple_blob.go
@@ -51,6 +51,7 @@ func NewSimpleBlobie(rect image.Rectangle, options *BlobOptions) Blobie {
 		isStillBeingTracked: true,
 		noMatchTimes:        0,
 		crossedLine:         false,
+		customProperties:    make(map[string]interface{}),
 	}
 	if options != nil {
 		blobie.TrackTime = []time.Time{options.Time}
@@ -87,10 +88,10 @@ func NewBlobieDefaults(rect image.Rectangle) *SimpleBlobie {
 		isExists:            true,
 		isStillBeingTracked: true,
 		noMatchTimes:        0,
-
-		classID:     -1,
-		className:   "No class",
-		crossedLine: false,
+		classID:             -1,
+		className:           "No class",
+		customProperties:    make(map[string]interface{}),
+		crossedLine:         false,
 	}
 }