Abstract: In order to make full use of scallop and increase its added value, crushed scallop adductor muscle was processed into scallop hydrolysate seasoning powder by hydrolysis with flavourzyme and subsequent spray drying. The hydrolysis of scallop adductor muscle was optimized by orthogonal array design based on amino acid nitrogen content in its hydrolysate. On the basis of a three-variable, three-level Box-Benhnken experimental design, response surface methodology was used to optimize the spray drying conditions of scallop adductor muscle hydrolysate. The power yield of spray drying for scallop adductor muscle hydrolysate (Y) was investigated with respect to air inlet temperature (X1), air outlet temperature (X2) and ventilation rate (X3). The optimal hydrolysis conditions were determined as follows: flavourzyme dosage of 1200 U/g and solid-to-liquid of 1:4 (g/mL) for a hydrolysis duration of 5 h at 45 ℃ and under these conditions, the amino acid nitrogen content in scallop adductor muscle hydrolysate was (1.03 ± 0.01)%, which was increased by 0.12%－0.74% when compared with previously reported results. A regression model describing the effects of X1, X2 and X3 on Y was obtained as follows: Y = －2867.5825 ＋19.5670X1 ＋34.7780X2＋779.4000X3－0.0761X12－0.2284X22－0.0433X32. The optimal conditions for spray drying of scallop adductor muscle hydrolysate were air inlet temperature 128.60 ℃, air outlet temperature 76.15 ℃, ventilation rate 0.9 m3/min, resulting in a power yield of 64.82%. A product that had a moisture content of 4.09% and was good in solubility, color and flavor was obtained. 

Key words: enzymatic hydrolysis, amino acid nitrogen, spray drying, scallop hydrolysate seasoning powder