diff --git a/masp_primitives/src/asset_type.rs b/masp_primitives/src/asset_type.rs
index b36bf46a..24a48021 100644
--- a/masp_primitives/src/asset_type.rs
+++ b/masp_primitives/src/asset_type.rs
@@ -148,6 +148,15 @@ impl AssetType {
     pub fn get_nonce(&self) -> Option<u8> {
         self.nonce
     }
+
+    /// Deserialize an AssetType object
+    pub fn read<R: std::io::Read>(reader: &mut R) -> std::io::Result<Self> {
+        let mut atype = [0; crate::constants::ASSET_IDENTIFIER_LENGTH];
+        reader.read_exact(&mut atype)?;
+        AssetType::from_identifier(&atype).ok_or_else(|| {
+            std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid asset type")
+        })
+    }
 }
 
 impl PartialEq for AssetType {
diff --git a/masp_primitives/src/transaction/components/amount.rs b/masp_primitives/src/transaction/components/amount.rs
index 70e03438..6342a398 100644
--- a/masp_primitives/src/transaction/components/amount.rs
+++ b/masp_primitives/src/transaction/components/amount.rs
@@ -160,13 +160,9 @@ impl ValueSum<AssetType, i32> {
     /// different assets
     pub fn read<R: Read>(reader: &mut R) -> std::io::Result<Self> {
         let vec = Vector::read(reader, |reader| {
-            let mut atype = [0; 32];
+            let atype = AssetType::read(reader)?;
             let mut value = [0; 4];
-            reader.read_exact(&mut atype)?;
             reader.read_exact(&mut value)?;
-            let atype = AssetType::from_identifier(&atype).ok_or_else(|| {
-                std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid asset type")
-            })?;
             Ok((atype, i32::from_le_bytes(value)))
         })?;
         let mut ret = Self::zero();
@@ -195,13 +191,9 @@ impl ValueSum<AssetType, i64> {
     /// different assets
     pub fn read<R: Read>(reader: &mut R) -> std::io::Result<Self> {
         let vec = Vector::read(reader, |reader| {
-            let mut atype = [0; 32];
+            let atype = AssetType::read(reader)?;
             let mut value = [0; 8];
-            reader.read_exact(&mut atype)?;
             reader.read_exact(&mut value)?;
-            let atype = AssetType::from_identifier(&atype).ok_or_else(|| {
-                std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid asset type")
-            })?;
             Ok((atype, i64::from_le_bytes(value)))
         })?;
         let mut ret = Self::zero();
@@ -230,13 +222,9 @@ impl ValueSum<AssetType, i128> {
     /// different assets
     pub fn read<R: Read>(reader: &mut R) -> std::io::Result<Self> {
         let vec = Vector::read(reader, |reader| {
-            let mut atype = [0; 32];
+            let atype = AssetType::read(reader)?;
             let mut value = [0; 16];
-            reader.read_exact(&mut atype)?;
             reader.read_exact(&mut value)?;
-            let atype = AssetType::from_identifier(&atype).ok_or_else(|| {
-                std::io::Error::new(std::io::ErrorKind::InvalidData, "invalid asset type")
-            })?;
             Ok((atype, i128::from_le_bytes(value)))
         })?;
         let mut ret = Self::zero();
diff --git a/masp_primitives/src/transaction/components/transparent.rs b/masp_primitives/src/transaction/components/transparent.rs
index 85391e8c..daee2670 100644
--- a/masp_primitives/src/transaction/components/transparent.rs
+++ b/masp_primitives/src/transaction/components/transparent.rs
@@ -91,12 +91,7 @@ pub struct TxIn<A: Authorization> {
 
 impl TxIn<Authorized> {
     pub fn read<R: Read>(reader: &mut R) -> io::Result<Self> {
-        let asset_type = {
-            let mut tmp = [0u8; 32];
-            reader.read_exact(&mut tmp)?;
-            AssetType::from_identifier(&tmp)
-        }
-        .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "invalid asset identifier"))?;
+        let asset_type = AssetType::read(reader)?;
         let value = {
             let mut tmp = [0u8; 8];
             reader.read_exact(&mut tmp)?;
@@ -138,12 +133,7 @@ pub struct TxOut {
 
 impl TxOut {
     pub fn read<R: Read>(reader: &mut R) -> io::Result<Self> {
-        let asset_type = {
-            let mut tmp = [0u8; 32];
-            reader.read_exact(&mut tmp)?;
-            AssetType::from_identifier(&tmp)
-        }
-        .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "invalid asset identifier"))?;
+        let asset_type = AssetType::read(reader)?;
         let value = {
             let mut tmp = [0u8; 8];
             reader.read_exact(&mut tmp)?;
diff --git a/masp_proofs/src/prover.rs b/masp_proofs/src/prover.rs
index 355fb350..7f7cba20 100644
--- a/masp_proofs/src/prover.rs
+++ b/masp_proofs/src/prover.rs
@@ -247,7 +247,7 @@ impl TxProver for LocalTxProver {
     fn binding_sig(
         &self,
         ctx: &mut Self::SaplingProvingContext,
-        assets_and_values: &I128Sum, //&[(AssetType, i64)],
+        assets_and_values: &I128Sum,
         sighash: &[u8; 32],
     ) -> Result<Signature, ()> {
         ctx.binding_sig(assets_and_values, sighash)