There were references (Botta, 1994; TIS,1986) related the TVB values with the freshness of the shrimps. The TVB value of 620 mg N/100 g sample was considered fresh, 6 30 mg N/100 g sample was acceptable and >40 mg N/100 g sample was not suitable for consumption. According to the Thai standard for frozen shrimps and prawns of 30 mg N/100 g sample (TIS, 1986).