Effects of various cryostabilisers on protein functionality in frozen-stored minced blue whiting muscle: The importance of inhibiting formaldehyde production

Abstract

Addition of several maltodextrins (dextrose equivalent 9, 12, 18 and 28) or sucrose to minced blue whiting muscle slowed down decreases in protein solubility and viscosity during storage at –20 and –10 °C. These effects were greater at –20 °C, and DE 18 maltodextrin seemed to be the most effective treatment at both temperatures. Conversely, sucrose was as effective as maltodextrins at –20 °C, but showed hardly any effect at –10 °C. A high correlation (likely causal) was found between the effectiveness of cryostabilisers in preventing protein alterations and their effectiveness in inhibiting formaldehyde production, particularly at –10 °C. Additionally, a sigmoidal relationship between protein solubility and formaldehyde content was found at this temperature, which supports the hypothesis of the cooperative nature of the effect of formaldehyde (i.e. an autocatalytic process) on protein alterations, reinforcing the determinist perspective of the process.