diff --git a/deeprank2/trainer.py b/deeprank2/trainer.py
index 8f5b5d64..f60bf750 100644
--- a/deeprank2/trainer.py
+++ b/deeprank2/trainer.py
@@ -873,9 +873,17 @@ def test(
     def _load_params(self) -> None:
         """Loads the parameters of a pretrained model."""
         if torch.cuda.is_available():
-            state = torch.load(self.pretrained_model)
+            state = torch.load(self.pretrained_model, weights_only=False)
         else:
-            state = torch.load(self.pretrained_model, map_location=torch.device("cpu"))
+            state = torch.load(self.pretrained_model, map_location=torch.device("cpu"), weights_only=False)
+
+        features_transform = state["features_transform"]
+        for value in features_transform.values():
+            if value["transform"] is None:
+                continue
+
+            # Deserialize the function
+            value["transform"] = dill.loads(value["transform"])
 
         self.data_type = state["data_type"]
         self.model_load_state_dict = state["model_state"]
@@ -901,7 +909,7 @@ def _load_params(self) -> None:
         self.node_features = state["node_features"]
         self.edge_features = state["edge_features"]
         self.features = state["features"]
-        self.features_transform = state["features_transform"]
+        self.features_transform = features_transform
         self.means = state["means"]
         self.devs = state["devs"]
         self.cuda = state["cuda"]
@@ -912,16 +920,12 @@ def _save_model(self) -> dict[str, Any]:
         features_transform_to_save = copy.deepcopy(self.features_transform)
         # prepare transform dictionary for being saved
         if features_transform_to_save:
-            for key in features_transform_to_save.values():
-                if key["transform"] is None:
+            for value in features_transform_to_save.values():
+                if value["transform"] is None:
                     continue
+
                 # Serialize the function
-                serialized_func = dill.dumps(key["transform"])
-                # Deserialize the function
-                deserialized_func = dill.loads(serialized_func)  # noqa: S301
-                str_expr = inspect.getsource(deserialized_func)
-                match = re.search(r"[\"|\']transform[\"|\']:.*(lambda.*).*,.*[\"|\']standardize[\"|\'].*", str_expr).group(1)
-                key["transform"] = match
+                value["transform"] = dill.dumps(value["transform"])
 
         state = {
             "data_type": self.data_type,
diff --git a/tests/test_trainer.py b/tests/test_trainer.py
index b57ffdd6..0194e1c1 100644
--- a/tests/test_trainer.py
+++ b/tests/test_trainer.py
@@ -5,7 +5,9 @@
 import tempfile
 import unittest
 import warnings
+import uuid
 
+import numpy
 import h5py
 import pandas as pd
 import pytest
@@ -124,6 +126,32 @@ def setUpClass(class_) -> None:
     def tearDownClass(class_) -> None:
         shutil.rmtree(class_.work_directory)
 
+    def test_save_transform_function(sef) -> None:
+        dataset = GridDataset(
+            hdf5_path="tests/data/hdf5/1ATN_ppi.hdf5",
+            subset=None,
+            features=[Efeat.VDW],
+            target=targets.IRMSD,
+            task=targets.REGRESS,
+        )
+        trainer = Trainer(CnnRegression, dataset)
+        trainer.features_transform = {"float32": {"transform": lambda t: t.astype(numpy.float32), "standardize": True}}
+
+        state = trainer._save_model()
+        assert "features_transform" in state
+        assert "float32" in state["features_transform"]
+
+        tmp_path = os.path.join(tempfile.gettempdir(), uuid.uuid4().hex + ".pth")
+        try:
+            torch.save(state, tmp_path)
+
+            trainer.pretrained_model = tmp_path
+            trainer._load_params()
+        finally:
+            os.remove(tmp_path)
+
+        trainer.features_transform["float32"]["transform"](numpy.array([0.0]))
+
     def test_grid_regression(self) -> None:
         dataset = GridDataset(
             hdf5_path="tests/data/hdf5/1ATN_ppi.hdf5",