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

Introduction

Shrimps are one of the most popular seafood globally due to its desirable flavor, high protein content (FAO, 2019) [1] . These are highly nutritious due to their significant amount of essential omega-3 and omega-6 fatty acids contents (Oksuz et al., 2009) [2] . These fatty acids are essential for maintaining normal brain structure and function, preventing coronary heart disease, diabetes, and some types of cancer, and must be received through diet because the human body is unable to produce them. Presently, in both domestic and international markets demand for ready to eat shrimp (RTE) products has been steadily increasing due to the recognized health benefits of shrimp and shrimp-based food products. Thermal processing is one of the most widely used and significant techniques in the seafood industry for extending the shelf life of ready-to-eat shrimp in masala. The process involves subjecting the product to a predetermined temperature for a specified duration to inactivate pathogenic microorganisms that may pose public health risks, as well as spoilage and enzymes that can compromise product stability during storage (Karel et al., 1975) [3] . In India, processing of retort pouch is increasingly preferred over convectional metal containers because of its multiple advantages, including lower cost, thinner profile, minimized processing time, reduced loss of nutrients, ease of opening, direct consumption from the pouch, compact storage requirements and convenient disposal (Mermelstein, 1978) [4] . Retort pouch technology helps to prevent overcooking and excessive softening of food, thereby preserving desirable taste and texture. Most of the retort pouches are manufactured using a four-ply laminate structure, comprising an outer layer of polyester for mechanical strength, a nylon layer for puncture resistance, an aluminum foil layer for barrier properties, and an inner layer of polypropylene, which is in direct contact with the food. Polypropylene has a melting point of approximately 138 °C (280 °F), which is well above the standard thermal sterilization temperature of 121 °C (250 °F), ensuring structural integrity during processing (Majumdar et al., 2017) [5] . Color is a critical quality attribute in thermally processed seafood products, as it directly influences consumer acceptability. Thermal processing alters the sensory and textural properties of shrimp primarily through protein denaturation. Texture is one of the most crucial aspects in consumption of shellfish (Cheret et al., 2005) [6] . Hardness, cohesiveness, gumminess, chewiness, greasiness, and juiciness are only some of the characteristics that are included in the term texture (Brandt et al., 1963) [7] . Texture is particularly important because it undergoes significant changes during extended heating, whereas shrimp flavor develops relatively early in the process and remains largely stable during prolonged cooking (Ma et al., 1983) [8] . The unique flavor of black tiger shrimp (Penaeus monodon) makes it highly desirable, texture, and nutritional benefits. In India, a variety of culinary practices are employed to develop thermally processed shrimp-based products. The incorporation of spices and aromatic compounds enhances the flavour profile; Nevertheless, these additives might also influence the product's viscosity, color, and heat transfer characteristics during thermal sterilization (Manju et al., 2007; Sreenivasan et al., 2010) [9,10] . Ready to eat shrimp in masala is a product prepared using shrimp, Indian spices and other ingredients and it holds a significant market potential across India. The present investigation aimed to optimize the processing conditions for shrimp in masala packed in flexible retortable pouches and to evaluate the resulting changes in textural, biochemical and sensory attribute of the product post-processing.

Materials and Methods

Materials

Fresh black tiger shrimp (Penaeus monodon) samples weighing 71.20±24.53 gm (16-20 count/kg) were procured from the landing centre in Mangaluru, Karnataka, India, and brought to the Department of Fish Processing Technology, College of Fisheries Mangaluru in insulated ice box (ice to shrimp ratio 1:1). They were washed with chilled potable water, peeled, beheaded, deveined. The product was packed in a laminated flexible pouch (four-ply) made of 70 μm polypropylene (inner cast), 14 µm nylon (middle layer), 9 μm aluminum foil, and 12 μm polyester (outer layer). In this study, 300 g pouches (150 × 200 mm) made by Floeter India Retort Pouches Pvt Ltd in Haryana, India, were used. The pilot-scale horizontal over pressure retorting unit (Lakshmi Engineering Works, Chennai, India) was used for the heat processing. Analytical reagent (AR) grade chemicals and glassware were used throughout the study.

Preparation of Shrimp Masala

The masala was prepared using a standardized method involving dry masala paste and wet pastes. The wet paste was made up of tomato, onion, ginger, garlic, green chilli, turmeric powder and curry leaves were fried in small quantity of oil, whereas, dry masala paste consisted of Byadagi chilli, black pepper, poppy seeds, cinnamon, turmeric, coriander, cumin and salt, which were lightly roasted in a minimal amount of oil over medium flame. The ingredients used for masala preparation are listed in Table 1.

The prepared ingredients were blended into a fine paste. Refined sunflower oil was heated on a pan, followed by addition of chopped onion, green chilli, curry leaves, garlic, ginger, turmeric powder and shallots, which were fried over low flame for 2-3 minutes until light brown color developed. The wet paste (Onio-tomato mixture) was then incorporated and cooked until the mixture changed color. Subsequently, the dry masala, tamarind paste, and coconut milk were added and gently simmered over law flame until a characteristics aroma was released. Finally, salt and an appropriate quantity of water were added to adjust taste and consistency, and cooking was continued until the masala reached a gentle boil. The dressed shrimps were hot blanched in 6% brine (100±2 ֯ C) for 10 min and added into the prepared masala followed by boiling. Filling and sealing of the pouches Retort pouches were filled with approximately 250 ± 5 g of hot shrimp masala. Thermocouple tips were placed into shrimp pieces at the slowest rate of heating point, and certain pouches have packaging glands made of stainlesssteel (Model GKJ 13009C052). Sterile tissue was used to clean the sealing surfaces. To achieve the required F 0 values, pouches were steam-exhausted, hermetically sealed, and placed into the retort chamber for thermal processing.

Thermal processing of Black tiger shrimp in masala

To reach the desired lethality (F 0 8 and 9 minutes), the shrimp masala pouches were thermally processed. After that, they were cooled and allowed to air dry before being stored and analyzed. [11] technique, processing time was calculated using Ball's mathematical model.

Quality evaluation The proximate, biochemical, and microbiological analysis

The moisture, ash, fat, and crude protein contents of fresh shrimp and thermally processed shrimp in masala at different F 0 values were determined by following the AOAC (2010) [12] standard procedures. The values were expressed as% (wet weight basis). Biochemical parameters, including TVB-N, TMA-N, PV, FFA, TBARS, indole, and pH, were analyzed for both fresh and thermally processed shrimp in masala. TVB-N and TMA-N were estimated using Conway's micro-diffusion method (Conway, 1962) [13] ,

while TBARS values were determined following the procedure of Raghavan and Hultin (2005) [14] . Free fatty acids (FFA) were analyzed according to Dyer and Morten (1956) [15] , and peroxide values (PV) were assessed using the method of Kirk and Sawyer (1991) [16] . Indole content was determined following Cheuk et al. (1981) [17] , and pH was measured using a digital pH meter. In addition, the total plate count (TPC) of fresh shrimp meat was determined by the spread plate technique (ICMSF, 1986) [18] .

Commercial sterility test

Commercial sterility was evaluated by IS:2168 (1971) [19] . Processed samples were incubated at 37 °C for 15 days and at 55 °C for 5 days to detect any surviving mesophilic or thermophilic bacteria. After incubation, the pouches were aseptically cut open, and 1-2 g of sample was collected using sterilized forceps and inoculated into sterilized fluid thioglycolate broth contained in test tubes. To establish anaerobic conditions, a layer of sterilized liquid paraffin was added over the broth, which was then incubated at 37 °C for 48 hours and 55 °C for 5 days, respectively. to assess the commercial sterility of the product.

Texture profile analysis

A textural property of fresh and thermally processed black tiger shrimp products were evaluated using a texture analyzer (TA-XT Plus, Stable Micro Systems, UK). A twofold compression test was conducted using a cylindrical probe (75 mm in diameter) fitted with a 50 N load cell. The conventional procedure outlined by Bourne (1978) [20] and further modified by Mohan et al. (2006) [21] was followed, compressing the samples twice to 40% of their initial height at a crosshead speed of 12 mm/min.

Color Analysis

A spectrocolorimeter (ColorFlex EZ, HunterLab, Reston, VA, USA) with an 8° diffuse geometry and a D65/10° standard illuminant was used to quantify the color of every sample. Prior to analysis, the equipment was calibrated using the manufacturer's standard white and black reference tiles. The CIELAB color system was used to record the color, yielding values for L* (lightness), a* (red-green), and b* (yellow-blue).

Sensory evaluation

The sensory analysis of the processed product in masala medium was evaluated by a trained panel of 25 members, scientists, researchers and postgraduate students, using 9point hedonic scale (Meilgaard et al., 1999) [22] . For 180 days of storage study, the processed retort pouches were kept in ambient conditions after conditioning. Samples were chosen at randomly for sensory analysis after post-storage. The pouches were reheated in boiling water for 10 minutes before being evaluated. For objective evaluation, the samples were served warm on coded white enamel plates, and the attributes assessed included appearance, color, flavor, succulence, toughness, firmness, and overall acceptance.

Statistical analysis

All analyses were performed in triplicate for statistical evaluation. The findings were presented as mean ± standard deviation. To determine the mean difference (p < 0.05), the Duncan multiple range test was used. The statistical program SPSS 27.00 was utilized to analyze the experimental findings.

Results and Discussion

Heat penetration characteristics

Black tiger shrimp masala packed in flexible retortable pouches were thermally processed at two lethality levels, F 0 8 and F 0 9 minutes. Heat penetration characteristics were determined by using data recorded with the Ellab system (Table 2). The retort chamber reached sterilizing temperature rapidly in both cases, as shown by the come-up times of 5.5 minutes (F 0 8) and 6.5 minutes (F 0 9) (Figure 1). Stable heat transfer dynamics throughout processing were indicated by the little fluctuation in heating lag (Jh) and cooling lag (Jc) variables between treatments. For F 0 8 and F 0 9 min, the heating curve slope (fₕ) was 26 and 25 minutes, respectively. The total process time taken to reach lethality F 0 8 and F 0 9min shrimp in masala were 30.59 and 32.67 min, respectively. Cook value indicates the extent of cooking of the products were 94.07 for F 0 8 and 90.16 min for F 0 9. A slight reduction in cook value was observed in shrimp processed at F 0 9 min compared to F 0 8 min, which may be attributed to the shorter come-up time, as both parameters are interrelated. It was observed from the results that as F 0 value increased, the total process time also increased proportionally. The recommended F 0 value for fish and fishery products ranges from 5-20 min (Frott and Lewis, 1994) [23] . Sreenath et al. (2007) [24] reported a processing time of 48 minutes and a cook value of 95.4 minutes for shrimp curry processed in TFS cans. Comparable finding was reported by Dasan et al. (2021) [25] documented process times of 37.11 and 39.88 minutes and CV of 84.07 and 92.41 minutes for masala-packed shrimp processed at F 0 8 and F 0 9 min. However, the processing times obtained in the present study were slightly lower than those reported for shrimp kuruma and shrimp in masala, which may be attributed to differences in shrimp species, container size and composition, and product consistency [26] reported 80.47% moisture, 17.1% protein, 1.23% fat, and 0.95% ash in P. monodon. Similarly, Akintola et al. (2013) [27] and Marichamy et al. (2011) [28] documented moisture and protein contents of 75.18% and 20.34%, respectively. More recently, Yang et al. (2025) [29] reported values of 81.67% moisture, 17.1% protein, 0.6% fat, and 1.0% ash in black tiger shrimp. The variation in proximate composition among different studies may be attributed to factors such as species, size, diet, and environmental conditions.

Biochemical analysis

For 180 days, the biochemical of shrimp masala was assessed at room temperature. Changes in biochemical parameters like TVB-N, TMAN, TBA, FFA and pH which were analyzed for fresh and processed shrimp in masala for 180 days of storage (Figure 2). Fresh black tiger shrimp showed lower content of all biochemical parameters as compared to processed shrimp. During entire 180 storage days biochemical parameters were increased for thermally processed shrimp masala at F 0 8 and F 0 9. TVB-N and TMA-N values for the fresh shrimp were 5.64 and 2.84 mg N / 100g, respectively. Following thermal processing, the TVB-N content increased to 8.31 mg N/100 g for F₀ 8 and 8.87 mg N/100 g for F₀ 9. After 180 days of storage, these values further increased to 17.27 mg N/100 g and 18.16 mg N/100 g, respectively. Protein and TMAO degradation during heating and storage was the cause of the increase in this study. According to previous reports on retorted salmon and shrimp (Mohan et [21,30,31] , these results were consistent. The spoiling threshold of 20 mg N/100 g was maintained by all samples. TMA-N content of fresh black tiger shrimp was 2.84 mg N/100g. After thermal processing the samples had slightly increased values of 3.03 mg N/100g (F 0 8) and 3.12 mg N/100g (F 0 9). By 180 days, TMA-N rose to 7.10 mg N/100g (F 0 8) and 7.78 mg N/100g (F 0 9), which is due to the thermal degradation of TMAO into TMA. In the current investigation, the TMA-N content was slightly closer to the value reported by Kaur et al. (2016) [32] , which was 3.92 mg N/100g in fresh Black tiger shrimp. Therefore, the breakdown of proteins, amino acids, and other nitrogenous substances, including TMAO, may be the cause of the rise in TMA-N and TVB-N (Chia et al., 1983; Mohan et al., 2006) [33,21] . The current analysis is in line with earlier research that found comparable TVBN and TMAN trends in thermally processed shrimp in masala (Dasan et [25,34,35] . The initial peroxide value (PV) of fresh shrimp was 1.86 mEq O₂/kg. Thermally processed samples recorded PV of 2.03 mEq O₂/kg F 0 8) and 2.40 mEq O₂/kg (F 0 9). During storage, PV increased progressively, reaching 7.15 mEq O₂/kg and 7.84 mEq O₂/kg, respectively. This increase was attributed to oxidative changes in lipids induced by heat and oxygen exposure. Previous studies have indicated that PV levels in the range of 10-20 mEq O₂/kg correspond to the onset of rancidity in fish products (Connell, 1995; Ahn & Min, 2005) [36,37] . Recently, Chavan et al., (2025) [38] observed similar trend in Pacu fish masala thermally processed at F 0 6 and F 0 7. TBARS content was 0.30 mg malondialdehyde/kg in fresh sample which indicates that the raw material was used of prime quality. Kaur et al. (2016) [32] reported that the TBA value in fresh Black tiger shrimp was 0.54 malonaldehyde/kg. Thermally processed shrimp products had values of 0.39 malondialdehyde/kg (F 0 8) and 0.42 malondialdehyde/kg (F 0 9). By day 180, the values reached 0.87 malondialdehyde/kg and 0.92 malondialdehyde/kg. The increase was attributed to secondary lipid oxidation during prolonged storage. Comparable TBARS trends in heat treated shrimp masala and pacu fish masala have been reported in previous studies (Dasan et al., 2021; Chavan et al., 2025) [25,38] . The free fatty acid (FFA) content of fresh shrimp was 0.18% oleic acid. Thermally processed shrimp samples showed initial values of 0.78% oleic acid and 0.80% oleic acid, which increased to 1.27% oleic acid and 1.42% oleic acid, respectively, by day 180 of storage. This was seen to be increased by thermal hydrolysis of the triglycerides. It has been reported that thermal processing has accelerated lipid degradation in fish (Aubourg et al., 1990; Medina et al., 1995) [39,40] . The values of FFA that were seen in the current study were acceptable. Likewise, progressive rise of free fatty acid content in pacu fish in masala with storage period of 150 days indicated by Chavan et al. (2025) [ 38] . The pH of fresh shrimp was 6.31, thermal processing decreased the pH to 5.71 (F 0 8) and 5.80 (F 0 9). As time went on during storage, pH gradually went to 6.40 and 6.46, respectively. This is attributed to the destruction of proteins and release of amines. The indole content in raw black tiger shrimp was found to be 0.98 µg/100 g, indicating a high degree of freshness of the shrimp used in the present study. Since indole formation primarily results from microbial activity, it was not detected in the thermally processed samples. Similar result was reported by Mohan et al. (2006) [21] in shrimp kuruma. The initial total plate count (TPC) of fresh black tiger shrimp was recorded 4.40 × 10 3 CFU/g, indicating a moderate level of microbial load. Notably, potential bacterial pathogens such as Salmonella, E coli, Vibrio spp, Listeria spp and Staphylococcus aureus were not detected in fresh and thermally processed shrimp samples. This absence of pathogenic microorganisms suggests effective hygienic practices during handling and processing.

Commercial sterility test

The commercial sterility of thermally processed shrimp masala packed in flexible retortable pouches was evaluated.

No turbidity or microbial growth was observed in thioglycolate broth after incubation at 37°C for 48 hours and at 55°C for 4 days. Both the products, processed at F 0 8 and 9 minutes, remained sterile throughout the 180 days ambient storage period. This research showed that the main safety concern in low-acid seafood products, Clostridium botulinum, as well as vegetative cells and heat-resistant spores, could be completely inactive by the total lethality achieved during retort processing. These findings are consistent with earlier studies on pacific whiteleg shrimp in masala (Dasan et al., 2021) 25] , tilapia fish masala (Taral et al., 2024) [41] and pacu fish in masala (Chavan et al., 2025) [38] . The use of validated retort conditions and effective heat penetration ensured microbial safety and contributed to an extended shelf life.

Color analysis

The color parameters of shrimp masala exhibited significant changes over 180 days of ambient storage (Table 4). The fresh shrimps had lightness (L*) value 52. [29] reported that L* value (43.04), b* value (7.18) and a* value (28.49) in black tiger shrimp. The main pigments in shrimp muscle are carotenoids, including astaxanthin and canthaxanthin (Okada et al.,1994) [42] . (a*) value and yellowness (b*) value of processed shrimps were increased significantly, due to enhanced pigment intensity and browning reactions. The muscle tissue produced reddish-orange colors due to the exposure and intensification of carotenoid pigments, particularly astaxanthin (Okada et al., 1994) [42] . The oxidation of myoglobin, which increases redness and can decrease lightness, is the primary cause of color changes in meat when exposed to high temperatures (Boles, 2010) [44] .

Recently, thermally processed tilapia in masala and pacu fish in masala showed a growing tendency in color parameters with higher F 0 values (Taral et al., 2023 and Chavan et al., 2025) [41,38] . Higher F 0 values showed increased darkening and pigment concentration, although F 0 8 and 9 did not significantly differ visually, suggesting that both treatments produced similar color transitions.

Texture profile analysis

Textural changes in shrimp masala resulting from thermal processing and subsequent storage were assessed using texture profile analysis (TPA). The texture profile analysis (TPA) of black tiger shrimp masala processed at F 0 8 and 9 minutes revealed significant variations in hardness, springiness, gumminess, cohesiveness and chewiness during 180 days of ambient storage study (Table 5). The fresh black tiger shrimp exhibited gumminess (1.73 Kgf), cohesiveness (0.55), chewiness (1.20 Kgf•mm), hardness (3.14 Kgf), and springiness (0.69 mm). After thermal processing, these values increased due to protein denaturation and structural tightening (Mohan et al., 2006). Hardness gradually decreased throughout the entire period of storage, decreasing from 3.65 and 3.57 kg force in thermally shrimp samples (F 0 8 and 9 min, respectively) to 2.02 and 1.98 kg force after 180 days. This decrease was attributed to moisture loss and muscle weakness caused on by heat. At 180 days, springiness decreased gradually but not significantly from 0.67 (F 0 8) to 0.65 (F 0 9) mm at the beginning to 0.52 (F 0 8) to 0.51(F 0 9) mm, suggesting a decrease in the elastic recovery of muscle tissue with increasing F 0 values. The gumminess and chewiness reduced dramatically in storage (p < 0.05) and followed the same trends as hardness. After 180 days of storage, chewiness decreased from 1.45 to 0.49 kgf mm at F 0 8 and from 1.36 to 0.48 Kgf. mm at F 0 9, while gumminess showed a slight reduction from 0.95 to 0.94 Kgf over the same period. The causes of these reductions include a decline in structural stability due to degradation of myofibrillar and connective tissue, and loss of moisture. The decrease in cohesiveness between 0.60 and 0.58mm in processed samples to 0.50 and 0.48mm (F 0 8 and F 0 9) at the end of storage may indicate a weakening of the internal bonding in the shrimp muscle. Nevertheless, the decrease was less significant when compared with hardness and gumminess. The better texture was observed in samples processed at F 0 8 than at F 0 9, which suggests that further increase in F 0 value led to increased myofibrillar structural weakening and breakdown (Sreenath et al., 2007; Mallick et al., 2010) [24,43] . In comparison to the higher F 0 value, the milder F 0 8 min treatment-maintained firmness, flavor, and color better.

There were no notable differences in toughness recorded during the storage period indicating that both treatments maintained an appropriate level of texture integrity. These findings proved that shrimp in masala processed at F 0 8 minutes had better sensory retention. Similar patterns were observed by Dasan et al. (2021) [25] , Taral et al. (2023) [41] , Ganachari et al. (2025) [45] and Chavan et al. (2025) [38], who observed that slightly responding shrimp masala, tilapia masala and pacu fish masala products were more accepted by consumers.

Sensory evaluation

During 180 days of storage, a trained panel evaluated the sensory qualities of shrimp masala. Appearance, color, flavor, firmness, succulence, toughness, and overall acceptability were assessed for samples processed at F 0 8 and 9 minutes (Figure 3). At day 0, both treatments received high scores across all attributes. Initially, appearance and succulence scored similar sensory score for both F 0 values, but later decreasing trend was observed by 180 days of storage period. At first, both treatments had the same overall acceptance score (8.80). Over the storage period, the scores gradually decreased. Samples treated at F 0 8 min maintained higher ratings than those handled at F 0 9 min by day 180. Overall acceptability scores were 8.10 (F 0 8) and 8.0 (F 0 9), respectively. In the F 0 9 sample, the decline in sensory quality was more noticeable. The accumulation of lipid oxidation products, texture weakening, and color oxidation were blamed for the gradual decline in scores. Compared to the higher F 0 value, the milder F 0 8 treatment better maintained firmness, flavor, and color. Throughout the storage period, no noticeable differences in toughness were found, suggesting that both treatments achieved a suitable level of texture integrity. According to these results, shrimp masala that was cooked for eight minutes at F 0 had better sensory retention over time. Dasan et al. (2021) [25] , Chavan et al. (2025) [38] , and Mohan et al. (2006) [21] showed similar findings, pointing to improved customer acceptance of moderately retorted, shrimp masala, pacu fish in masala and shrimp kuruma products. The findings highlighted how crucial it is to maximize thermal load in order to balance safety and sensory quality in seafood that is ready to eat.

Conclusion

This study successfully developed ready to eat thermally processed Shrimp masala packed in flexible retort pouches. Product was heat treated using a commercial pilot scale over pressure retort at two distinct lethality (F 0 8 and 9 min). The study demonstrated that the moisture content of both the products was significantly decreased, while the values of crude protein, crude fat, and ash contents were increased. Additionally, all biochemical constituents, including TVB-N, TMA-N, TBARS, FFA, and PV values, increased, but remained within an acceptable limit. Very little change in pH was seen throughout the storage period, suggesting that the product's microbiological quality was preserved. The products with good sensory acceptability and commercial sterility were processed at F 0 8 and 9 minutes. These results demonstrated that shrimp masala processed for F 0 8 minutes provided better sensory retention over time.

References

1. FAO. The State of World Fisheries and Aquaculture 2019. Towards Blue Transformation. Rome: FAO; 2019.
2. Oksuz A, Ozyurt G, Polat A, Ozyurt CE. Nutritional composition and mineral contents of shrimp species (Penaeus semisulcatus and Metapenaeus monoceros) from the Eastern Mediterranean. Food Chem. 2009;113(2):431-435.
3. Karel M, Fennema OR, Lund DB. Principles of Food Science. Part II: Physical Principles of Food Preservation. New York: Marcel Dekker; 1975.
4. Mermelstein NH. Developments in flexible packaging of foods. Food Technol. 1978;32(10):42-50.
5. Majumdar RK, Roy D, Saha A. Textural and sensory characteristics of retort-processed freshwater prawn (Macrobrachium rosenbergii) in curry medium. Int J Food Prop. 2017;20(11):2487-2498.
6. Cheret R, Delbarre-Ladrat C, De Lamballerie M, Verrez-Bagnis V. Muscle cell structure and texture of seafood products. J Food Sci. 2005;70(5):R93-R99.
7. Brandt MA, Skinner EZ, Coleman JA. Texture profile method. J Food Sci. 1963;28(4):404-409.
8. Ma CY, Holme J, Ledward DA. Food Proteins: Structure and Functionality. London: Applied Science; 1983.
9. Manju S, Jose L, Srinivasa Gopal TK, Ravishankar CN. Quality of seer fish (Scomberomorus commerson) steaks during ambient storage after retort processing in curry. J Food Process Preserv. 2007;31(3):227-242.
10. Sreenivasan S, Ravishankar CN, Balange AK. Thermal processing of ready-to-serve seer fish curry in retortable pouches. Fish Technol. 2010;47(2):133-140.
11. Stumbo CR. Thermobacteriology in Food Processing. 2nd ed. New York: Academic Press; 1973.
12. AOAC. Official Methods of Analysis of AOAC International. 18th ed, Rev. 3. Gaithersburg, MD: AOAC International; 2010.
13. Conway EJ. Micro-diffusion analysis and volumetric error. London: Crosby Lockwood; 1962.
14. Raghavan S, Hultin HO. Model system for testing the efficacy of antioxidants in muscle foods. J Agric Food Chem. 2005;53(11):4572-4577.
15. Dyer WJ, Morten L. Storage of frozen plaice fillets. J Fish Res Board Can. 1956;13:129-134.
16. Kirk S, Sawyer R. Pearson's Composition and Analysis of Foods. 9th ed. London: Longman Scientific & Technical; 1991.
17. Cheuk W, Finne G. Modified colorimetric method for determining indole in shrimp. J Assoc Off Anal Chem. 1981;64(4):783-785.
18. ICMSF. Microorganisms in Foods. Vol. 2: Sampling for Microbiological Analysis. 2nd ed. Toronto: Univ Toronto Press; 1986.
19. Bureau of Indian Standards. Methods of Test for Commercial Sterility of Thermally Processed Foods in Hermetically Sealed Containers. IS:2168. New Delhi: BIS; 1971.
20. Bourne MC. Texture profile analysis. Food Technol. 1978;32(7):62-66.
21. Mohan CO, Ravishankar CN, Bindu J, Geethalakshmi V, Srinivasa Gopal TK. Effect of thermal process time on quality of shrimp kuruma in retortable pouches and aluminum cans. J Food Sci. 2006;71(6):E496-E500.
22. Meilgaard M, Civille GV, Carr BT. Sensory Evaluation Techniques. 3rd ed. Boca Raton: CRC Press; 1999.
23. Frott R, Lewis AS. Canning of Meat and Fish Products. London: Chapman & Hall; 1994.
24. Sreenath PG, Xavier KA, Ravishankar CN, Bindu J, Srinivasa Gopal TK. Standardisation of process parameters for ready-to-eat squid masala in indigenous polymer-coated tin-free steel cans. Int J Food Sci Technol. 2007;42(10):1148-1155.
25. Dasan PG, Bojayanaik M, Gundubilli D, Banavath SN, Siravati MR, Obaliah MC. Heat penetration characteristics and quality of ready-to-eat shrimp in masala (Litopenaeus vannamei) in flexible retortable pouches. J Food Process Preserv. 2021;45(5):e15411.
26. Sriket P, Benjakul S, Visessanguan W, Kijroongrojana K. Comparative studies on chemical composition and thermal properties of black tiger shrimp (Penaeus monodon) and white shrimp (Penaeus vannamei) meats. Food Chem. 2007;103(4):1199-1207.
27. Akintola SL, Brown A, Bakare A, Osowo OD, Bello BO. Effects of hot smoking and sun-drying processes on nutritional composition of giant tiger shrimp (Penaeus monodon). Pol J Food Nutr Sci. 2013;63(4):227-237.
28. Marichamy G, Shanker S, Saradha A, Nazar AR, Haq MB. Study on proximate composition of P. monodon. Eur J Exp Biol. 2011;1(2):47-55.
29. Yang Y, Zhu C, Huang J, Zhou W, Chen J. Comparative studies of the effect of soaking with phosphate and salt on quality changes of white shrimp (P. vannamei) and black tiger shrimp (P. monodon). LWT. 2025;215:117303.
30. Rodriguez RJ, White JF, Arnold AE, Redman RS. Fungal endophytes: diversity and functional roles. New Phytol. 2009;182(2):314-330.
31. Biji KB, Shamseer RM, Mohan CO, Ravishankar CN, Mathew S, Gopal TKS. Effect of thermal processing on biochemical constituents of green mussel (Perna viridis) in tin-free-steel cans. J Food Sci Technol. 2015;52(10):6804-6809.
32. Kaur BP, Rao PS, Nema C. Effect of high-pressure processing on physicochemical and microbial quality of black tiger shrimp (Penaeus monodon). Innov Food Sci Emerg Technol. 2016;33:40-48.
33. Chia SS, Baker RC, Hotchkiss JH. Quality comparison of thermoprocessed fishery products in cans and retortable pouches. J Food Sci. 1983;48(5):1521-1525.
34. Tekade V, Bojayanaik M, Chavan SD, Banavath SN, Siravati MR, Gundubilli D, et al. Heat penetration characteristics and quality evaluation of pangasius (Pangasius hypophthalmus) chunks in masala using retort pouches. Eur J Nutr Food Saf. 2024;16(11):7891.
35. Tameshwar T, Bojayanaik M, Tekade V, Chavan SD, Gundubilli D. Optimizing the use of flexible retort pouches for ready-to-eat cobia (Rachycentron canadum) fish chunks in curry medium. Eur J Nutr Food Saf. 2024;16(11):130-144.
36. Connell JJ. Control of Fish Quality. 4th ed. Oxford: Fishing News Books; 1995.
37. Ahn DU, Min B. Mechanism of lipid peroxidation in meat and meat products: A review. Food Sci Biotechnol. 2005;14(1):152-163.
38. Chavan SD, Bojayanaik M, Ganachari J, Alakuntla P, Thimmappa A, Vaghabhai TP, et al. Thermal processing and shelf-life evaluation of red-bellied pacu (Piaractus brachypomus) fish masala in retort pouches. Fish Technol. 2025;62(3).
39. Aubourg SP, Sotelo CG, Gallardo JM. Changes in flesh lipids and fill oils of albacore (Thunnus alalunga) during canning and storage. J Agric Food Chem. 1990;38(3):809-812.
40. Medina I, Sacchi R, Aubourg SP. A 13C-NMR study of lipid alterations during fish canning: Effect of filling medium. J Sci Food Agric. 1995;69(4):445-450.
41. Taral PV, Manjanaik B, Baraiya KG, Chavan SD, Chavan MR, Fekar T, et al. Thermal processing optimization and quality assessment of GIFT fish in masala using retort pouches. J Exp Zool India. 2023;26(2):1849-1856.
42. Okada S, Nur-Ebrhan SA, Yamaguchi Y. Carotenoid composition in exoskeleton of black tiger prawn. Fish Sci. 1994;60:213-215.
43. Mallick AK, Gopal TS, Ravishankar CN, Vijayan PK, Geethalakshmi V. Changes in instrumental and sensory properties of Indian white shrimp in curry medium during retort pouch processing at different F0 values. J Texture Stud. 2010;41(5):611-632.
44. Boles JA. Thermal Processing. Singapore: WileyBlackwell; 2010.
45. Ganachari J, Bojayanaik M, Chavan SD, Fernandes DJ. Effect of thermal processing on quality and shelf life of black tiger shrimp (Penaeus monodon) curry in retort pouches during ambient storage. Int J Adv Biochem Res. 2025;9(8):482-491.