Optimization of thermal processing and quality evaluation of retort-pouch processed black tiger shrimp (Penaeus monodon) in masala

The present study evaluated the impact of thermal process time on the physicochemical, microbial, textural, and sensory quality of retort-processed black tiger shrimp (Penaeus monodon) in masala packed in flexible pouches. Products were processed at two different lethality levels (F0 8 and F0 9 minutes) using a pilot-scale overpressure retort and stored under ambient conditions for 180 days. Heat penetration studies confirmed the stable thermal profiles with process times of 30.59 and 32.67 minutes, achieving the recommended lethality for low-acid seafoods. Thermal processing reduced moisture content while increasing protein, fat, and ash levels compared with fresh shrimp. Biochemical parameters (TVB-N, TMA-N, TBARS, FFA, and PV) showed gradual increases during storage but remained within acceptable limits, whereas pH values exhibited minimal variation. Commercial sterility tests confirmed the absence of microbial growth and ensured product safety. Color analysis revealed a decline in lightness with corresponding increases in redness and yellowness during storage. Texture profile analysis indicated an initial increase in hardness and chewiness after processing, followed by significant reductions over time, with greater softening observed in F0 9 samples compared with F0 8. Sensory scores decreased slightly during storage but remained within acceptable levels, with F0 8 samples retaining superior sensory and textural attributes. Overall, retort pouch processing produced a safe, shelf-stable shrimp masala with a 180-day ambient shelf life, with F0 8 demonstrating better quality retention, underscoring its suitability for ready-to-eat shrimp products.