ABSTRACTEarlier studies indicated that the incorporation of shrimp (Pundulus jordani) in a fish‐shrimp portion increased the shelf life of machine‐separated fish muscle. This investigation was initiated to determine if shrimp could reduce the undesirable changes known to occur during frozen storage in one particular species of rockfish (Sebasfes melunops). After mixing different ratios of shrimp with minced fish muscle, the portions were frozen at — 34°C for 2 hr, packed loosely in polyethylene bags and held at —18°C until analyzed. The all‐fish portion was found to be unacceptable after 11 wk of frozen storage. Increasing the amount of shrimp in the portion markedly improved the acceptability and shelf‐life stability of the minced fish. This was directly related to the decreased formation of malonaldehyde and peroxides. The beneficial effects of incorporating shrimp with minced fish was attributed to substance(s) extractable in ethanol that exhibited antioxida