Effects of Tamarind (Tamarindus indica L.) Pulp-Based Marination on Physicochemical Quality, Oxidative Stability, Microbiological Characteristics, and Sensory Attributes of Eye of Round Beef

This study evaluated the effects of tamarind (Tamarindus indica L.) pulp as a marinade on the physicochemical quality (marinade liquid uptake, water-holding capacity, cooking loss, proximate composition, water activity, pH, color, and texture), oxidative stability (lipid oxidation), microbiological characteristics (mesophilic aerobic counts, Enterobacteriaceae, Gram-positive cocci, and molds and yeasts), and sensory attributes of eye of round beef (M. semitendinosus). Three treatments were compared: non-marinated control (C), brine (B; 2.5% NaCl), and NaCl with tamarind pulp (BPT; 2.5% NaCl + tamarind pulp). Tamarind incorporation significantly reduced pH and water-holding capacity, resulting in lower moisture content and higher ash and carbohydrate levels. BPT samples exhibited increased lightness (L*) and yellowness (b*) and reduced redness (a*), reflecting pigment contribution and acid-induced structural modifications. Texture profile analysis showed lower hardness and chewiness in BPT throughout storage, demonstrating improved tenderness. Lipid oxidation increased in B but remained controlled in BPT, highlighting the antioxidant potential of tamarind pulp. Tamarind selectively improved the microbiological profile by inhibiting Enterobacteriaceae and reducing mesophilic aerobic bacteria, although it was less effective in controlling molds and yeasts. Sensory evaluation showed that B treatment received the highest scores for flavor and overall acceptability, while BPT was characterized by fruity, acidic, and sweet notes, resulting in a distinctive sensory profile without reducing acceptability relative to the control. Overall, tamarind pulp substantially modulated the quality characteristics of marinated eye of round beef, providing advantages in oxidative stability, microbial control, and texture while also reducing water-holding capacity, altering color, increasing mold and yeast growth, and producing a distinctive sensory profile. These findings highlight both the potential and the limitations of tamarind pulp as a natural ingredient for clean-label meat products.