Tomato Seed Protein Concentrates: Effects of Methods of Recovery Upon Yield and Compositional Characteristics

Tomato seed protein concentrates (TSPC) were recovered from ground tomato seeds using alkaline extraction and three different protein coagulants (citric acid, citric acid/hydrochloric acid mixture or hydrochloric acid) at three coagulation temperatures (25°C 60°C or 95°C). The effect of this 3 × 3 protein recovery matrix on protein yield and composition of the freeze‐dried TSPC was studied. No significant effect of protein coagulants on protein yield (TCA/heat coaguable protein) was found but it was significantly higher with samples coagulated at 25°C than when heat coagulation was applied. Coagulation procedures at room temperature resulted in lower moisture, crude fat and ash concentration than heat coagulated samples. Lowry protein content of TSPC was not significantly affected by recovery methods but crude protein content after coagulation with citric acid resulted in significantly higher values of the samples coagulated at 25°C than those at 95°C.