Grape Seed Extract and Sodium Chloride as Interventions to Limit Clostridium perfringens Growth during Cooling

This study investigated the effects of sodium chloride (NaCl), grape seed extract (GSE), and cooling duration on the growth of Clostridium perfringens in cooked ground beef during slow exponential cooling. Meat samples containing 0-30 g/kg NaCl and 0-30 mL/kg GSE were cooled from 54.5°C to 7.2°C over 12, 15, 18, or 21 h. The programmed and actual cooling curves matched closely, ensuring consistent thermal conditions. C. perfringens growth was strongly influenced by NaCl concentration (P < 0.001), while GSE alone exhibited no significant effect (P > 0.05). Increasing NaCl levels significantly reduced net growth in a concentration-dependent manner. After 21 h of cooling, samples without NaCl reached approximately 7.2 log CFU/g, whereas the addition of 30 g/kg NaCl limited counts to approximately 2.3 log CFU/g, i.e., a reduction of nearly 5 log CFU/g. At 10 g/kg NaCl, growth was reduced by approximately 1.5-2.0 log CFU/g compared with the control. No significant interaction between NaCl and GSE was observed, indicating that reductions were primarily attributable to salt. These findings demonstrate that NaCl remains an effective control measure for C. perfringens during slow cooling, whereas GSE at practical concentrations provides minimal additional benefit. Studies focusing on optimizing multi-hurdle strategies to determine whether plant-derived antimicrobials can provide meaningful additional protection under practical meat-processing conditions are warranted.