diff --git a/image_processing/build_dataset.py b/image_processing/build_dataset.py
index 4c7456910c6a0253a6fbf6154dadd46e378d0e80..c618576cebdc857d38a2836eab4d342615adc789 100644
--- a/image_processing/build_dataset.py
+++ b/image_processing/build_dataset.py
@@ -124,6 +124,7 @@ def create_antibio_dataset(path='data/label_raw/230804_strain_peptides_antibiogr
         df[test] = df[test].map(lambda x :float(str(x).replace('>','').replace('<','')))
         #categorise each antibioresistance according to AST breakpoints table
         df[test+' cat']= 'NA'
+        df=df.copy()
         if 'mic' in test or 'vitek' in test :
             try :
                 df.loc[df[test] <= antibiotic_enterrobacter_breakpoints[test]['S'], test+ ' cat'] = 'S'
@@ -156,6 +157,8 @@ def create_antibio_dataset(path='data/label_raw/230804_strain_peptides_antibiogr
     df['path_ana'] = df['sample_name'].map(lambda x: create_fname(x,analyse='ANA'))
     df['path_aer'] = df['sample_name'].map(lambda x: create_fname(x, analyse='AER'))
 
+    print('Reference dataset extracted')
+
     return df