The Pacific white shrimp (L. vannamei) were supplied by the shrimp farm Aquadelta Agroindustrial S.A. (Mossoró, RN, Brazil), slaughtered by thermal shock in water and ice (1: 1), immediately treated with 3% sodium metabisulphite, transported in isothermal boxes to the Laboratory of Seafood Technology and Quality Control (LAPESC / UFERSA) where they were immediately washed, weighed, counted (number of pieces per kilogram), and kept under refrigeration (4°C) until the beginning of product development (time between slaughter and processing <2h).

The whole fresh shrimps (Fig. 1) were headless (leaving all shell from the first segment to the telson), washed (5 ppm chlorinated water), weighed, gutted, cut in the dorsal region (butterfly cut), and immersed in brine (10% NaCl + 5% sodium tripolyphosphate STPP) for 30 min, drained, immersed in the sweet-sour sauce (garlic, finger pepper, ginger, sugar, salt, rice vinegar and starch) for 15 min (for flavor absorption), drained, filled (manually) with cream cheese (Philadelphia Cream Cheese, Kraft Foods Brazil), weighed (yield calculation), vacuum packed, identified, frozen in ultrafreezer (-30ºC) and stored under freezer (-18ºC). The cost analysis of the formulation of the developed product was made based on the current market value of each ingredient used (shrimp, sweet-sour sauce and cream cheese).

For each step during the product development, samples were weighed, to calculate the partial and overall yield of the final product. The methodology adopted was described by Gonçalves [12Gonçalves AA. Estudo do processo de congelamento do camarão associado ao uso do aditivo fosfato. Porto Alegre: Universidade Federal do Rio Grande do Sul, Doctoral Thesis (Doutorado em Engenharia de Produção) 2005; 170.] according to the following Equations 1 and 2:

(1)

(2)

where: Pi = Initial weight (g); Pf = Final weight (g)

Fig. (1) Steps for the stuffed shrimp development.

The centesimal composition (fresh shrimp and stuffed shrimp) was carried out through the analysis of moisture (Method 950.46), crude protein (Method 940.25), total lipids (Method 948.15), and ash (Method 938.08), according to AOAC's official methodology [13 Official Methods of Analysis of Aoac international (2011) 18^th Ed., Aoac international, Gaithersburg, MD, USA, Official Method 950.46; 940.25; 948.15; 938.08.]. The pH, nitrogen of total volatile bases (TVBN) and trimethylamine (TMA) determination were performed according to the methodology recommended by Laboratório Nacional de Referência Animal (LANARA) [14Brazil Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Secretaria Nacional de Defesa Agropecuária (SDA), Laboratório Nacional de Referência Animal (LANARA) Métodos analíticos oficiais para o controle de Produtos de Origem Animal e seus ingredientes II - Métodos físicos e químicos 1981.]. All analyzes were done in triplicate.

The microbiological analyzes were carried out in accordance with Agência Nacional de Vigilância Sanitária (ANVISA, Brazil) - Resolução da Diretoria Colegiada (RDC) 12/2001 [15 Brazil. Ministério da Agricultura, Pecuária e Abastecimento (MAPA), Instrução Normativa N° 62, de 26 de agosto de 2003. Oficializa os Métodos Analíticos Oficiais para Análises Microbiológicas para Controle de Produtos de Origem Animal e Água. Diário Oficial da União, Brasília, 18/09/2003, Seção 1, Página 14.] using the Brazilian official methodology (Instrução Normativa No. 62, de 26/08/2003) [16Stone H, Sidel JL. Sensory Evaluation Practices 2004; 311.] The microorganisms analyzed for raw fresh shrimp were: total counts of mesophilic and psychrophilic bacteria, Salmonella sp., and coagulase-positive staphylococci; and for stuffed shrimp: total count of mesophilic and psychrophilic bacteria, Salmonella sp., coagulase positive staphylococci, and thermotolerant coliforms. All analyzes were performed at the Clinical and Immunological Analysis Center (CACIM, Mossoró, RN, Brazil).

Confirmed the microbiological safety, samples baked in a preheated gas oven (180ºC) for 20 min and submitted to the sensory panel evaluation. The sensory analysis was performed with 50 untrained panelists (32% men and 68% women, ranging in age from 18 to 48 years) who received still warm stuffed shrimp samples along with the evaluation form (structured hedonic scale of 9 points ranging from “extremely dislike” to “I liked very much”), which consisted in the subjective manifestation of the product tasted, demonstrating whether such a product pleases or displeases, whether it is accepted or not [17Pizato S, Kraieski J, Sarmento C, Prentice C. Avaliação da qualidade tecnológica apresentada por tilápia do Nilo (Oreochromis niloticus) enlatada. Semin Cienc Agrar 2012; 33(2): 667-74.
[http://dx.doi.org/10.5433/1679-0359.2012v33n2] , 18Teixeira E, Meinert EM, Barbetta PA. Análise Sensorial de Alimentos 1987; 180.]. The acceptability index (IA) was calculated considering that 100% is the maximum score achieved by the product (stuffed shrimp) and the decision criterion for the IA to be well accepted is at least 70% [19Dutcosky SD. Análise sensorial de alimentos 2^nd ed. 2007; 239., 20Scherr C, Ribeiro JP. Influência do modo de preparo de alimentos na prevenção da aterosclerose. Rev Assoc Med Bras (1992) 2013; 59(2): 148-54.
[http://dx.doi.org/10.1016/j.ramb.2012.10.001] [PMID: 23582556] ]. The consumer's buy intention was also evaluated using the Attitude Scale Test structured in five points that range from “I would certainly buy” to “I certainly would not buy” [17Pizato S, Kraieski J, Sarmento C, Prentice C. Avaliação da qualidade tecnológica apresentada por tilápia do Nilo (Oreochromis niloticus) enlatada. Semin Cienc Agrar 2012; 33(2): 667-74.
[http://dx.doi.org/10.5433/1679-0359.2012v33n2] , 20Scherr C, Ribeiro JP. Influência do modo de preparo de alimentos na prevenção da aterosclerose. Rev Assoc Med Bras (1992) 2013; 59(2): 148-54.
[http://dx.doi.org/10.1016/j.ramb.2012.10.001] [PMID: 23582556] ].

The shelf life study of stuffed, frozen, vacuum-packed shrimp stored for 180 days at -18°C was monitored every 45 days by microbiological (total count of mesophilic and psychrophilic bacteria, thermotolerant coliforms, Salmonella sp., and coagulase positive staphylococci) and physico-chemical (pH, TVBN, TMA) analyzes.

The means were compared using analysis of variance (ANOVA) and the effects were considered significant (by the Tukey test) when p ≤ 0.05. All analyzes were performed by the XLSTAT Trial Version 2018.2 software (Addinsoft 1995-2018).

The shrimp weighs at each step and the respective yields are shown in Table 1. For each 1,000g of shrimp, 43 units of shrimp were counted, which represents a shrimp with ~ 23g (per unit). After the headless shrimp step, the whole fresh shrimp lost 37.5% by weight, which represents a possibility of using this residue (head) for a new by-product development. After the brining step, 4.8% increase in weight was observed due to the incorporation of water by the presence of NaCl and STPP (humectant food additive). The immersion in the sweet-sour sauce, promoted the increment of 17% in weight, representing besides the weight gain, the improvement of the sensorial quality (tasty) by the incorporation of ingredients which can increase consumer acceptance. The cream cheese addition promotes an increase in weight of 15.70%. The weight loss by the head removal step was not totally recovered by the increase in the final weight (resulting from filling with cream cheese), but to a certain extent, the losses (overall yield of 41.87% from headless shrimp) was minimized by the ingredients used. The same situation was also found during the developing a value-added product (e.g. butterfly breaded shrimp) with the same species [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.].

The increase of 8.27% in the cost (comparing to the shrimp value) of the stuffed shrimp formulation (Table 2) was observed, and the final cost was R$ 32.27 (~US$ 7,70/kg raw fresh shrimp). However, when compared to ready-made dishes in restaurants and crustacean houses, this cost becomes lower than the average prices since dishes made with crustaceans reach the average value of R$ 40.00 (US$ 9.50) in local commerce. There are also no comparable products in the national market since most markets only sell shrimp in fresh/whole form or cooked or frozen.

Considering that this new product would be an ideal for sale per unit, and not per kilo, remembering the weight of shrimp of 23 g, the cost per piece would reach the value of R $ 0.75 (or US $ 0.18). The value added having the differential of being a “baked product” (less caloric than the breaded and fried ones) the stuffed shrimp becomes a viable and best option. When compared to fried, the grilled or baked shrimp is presented as the best nutritional option, because it contains fewer lipids, saturated fat, and can provide the desirable in polyunsaturated [21Chirol KA. Rendimento, composição química e perfil lipídico do camarão Litopenaeus vannamei de cultivo orgânico e convencional. Master Thesis (Mestre em Ciência e Tecnologia de Alimentos - Universidade Federal da Paraíba), João Pessoa, PB, Brazil 2007; 97.].

The results of the centesimal composition (moisture, protein, lipid, and ash) and physico-chemical (pH, TVBN and TMA) analyzes of fresh and stuffed shrimp are presented in Table 3.

Table 1
Partial yield (each step) and overall yield for the stuffed shrimp.

Table 2
Costs of the ingredients used for the stuffed shrimp development.

Table 3
Results of centesimal and physico-chemical composition analysis of fresh raw shrimp and stuffed shrimp.

The moisture content for fresh shrimp (72.67%) corroborates with that found in the scientific literature for L. vannamei [22Sriket 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: 1199-207.
[http://dx.doi.org/10.1016/j.foodchem.2006.10.039] ]: (72.8% organic farmed shrimp; 71.7% traditional farmed shrimp); however, lower than those found by other authors: 78% [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.], 77.2% [23Cadun A, Kışla D, Çaklı Ş. Marination of deep-water pink shrimp with rosemary extract and the determination of its shelf-life. Food Chem 2008; 109(1): 81-7.
[http://dx.doi.org/10.1016/j.foodchem.2007.12.021] [PMID: 260542 67] ], 84.7% [24Araujo DFS, Silvestre DD, Damasceno KSFSC, Pedrosa LFC, Seabra LMAJ. Composição centesimal e teor de colesterol do camarão branco do Pacífico. Cienc Rural 2012; 42(6): 1130-3.
[http://dx.doi.org/10.1590/S0103-84782012000600029] ], 74.1% [25Lira GM, Silva MCD, Silva KWB, et al. Avaliação da qualidade físico-química e microbiológica do camarão espigão (Xiphopenaeus kroyeri, Heller, 1862) in natura e defumado. Bol Cent Pesqui Process Aliment 2013; 31(1): 151-60.
[http://dx.doi.org/10.5380/cep.v31i1.32717] ], and 77.9% [26Perry KSP. Queijos: Aspectos químicos, bioquímicos e microbiológicos. Quim Nova 2004; 27(2): 293-300.
[http://dx.doi.org/10.1590/S0100-40422004000200020] ]. The percentage of moisture content for stuffed shrimp (66.27%) was lower and statistically different (p<0.05) when compared with the fresh one due to the incorporation, mainly of cream cheese, which increased the lipid content. Unfortunately, it was not found in the literature products like the one developed in the present research for comparison.

The protein content observed for fresh (24%, d.b.) was higher statistically different (p<0.05) comparing to stuffed shrimp (15.4%, d.b.). Since cream cheese is more energetic than protein, this difference can be justified. The protein content was close to the white shrimp [22Sriket 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: 1199-207.
[http://dx.doi.org/10.1016/j.foodchem.2006.10.039] ] from both organic (23.7%) and traditional farm (25.3%). Sriket et al. [23Cadun A, Kışla D, Çaklı Ş. Marination of deep-water pink shrimp with rosemary extract and the determination of its shelf-life. Food Chem 2008; 109(1): 81-7.
[http://dx.doi.org/10.1016/j.foodchem.2007.12.021] [PMID: 260542 67] ] evaluating the chemical composition of the monodon and vannamei species, observed lower protein content (19% and 22%, respectively). Gonçalves & Gomes [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.] also found lower values for fresh shrimp (19%), and for breaded shrimp (13%).

The lipids content for fresh raw shrimp was 0.7% (d.b.), remaining between the range of values found in the literature, however, lower (0.2% w.b.) than those found in the literature 0.3% [25Lira GM, Silva MCD, Silva KWB, et al. Avaliação da qualidade físico-química e microbiológica do camarão espigão (Xiphopenaeus kroyeri, Heller, 1862) in natura e defumado. Bol Cent Pesqui Process Aliment 2013; 31(1): 151-60.
[http://dx.doi.org/10.5380/cep.v31i1.32717] ] and 0.33% [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.]; while Chirol [22Sriket 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: 1199-207.
[http://dx.doi.org/10.1016/j.foodchem.2006.10.039] ] found higher values for both vannamei in traditional (1.32%, w.b.) and organic farm (1.47%, w.b.). For the stuffed shrimp, the lipid content was higher (13.9%, d.b.) and statistically different (p<0.05) when comparing to the fresh shrimp. According to Perry [27Phadungath C. Cream cheese products: A review. Songklanakarin J Sci Technol 2005; 27(1): 191-9.], dairy products, such as cream cheese, are rich in lipids, and according to the nutritional information table from the cream cheese manufacturer, the total fat (8.1 g a portion of 30 grams) is higher and can contribute to the increment of lipid content in stuffed shrimp.

The ash content found was 2.3% (d.b.) for fresh raw shrimp and in accordance to those found for pink shrimp Parapenaeus longirostris (2.3%) [24Araujo DFS, Silvestre DD, Damasceno KSFSC, Pedrosa LFC, Seabra LMAJ. Composição centesimal e teor de colesterol do camarão branco do Pacífico. Cienc Rural 2012; 42(6): 1130-3.
[http://dx.doi.org/10.1590/S0103-84782012000600029] ], and for L. vannamei from organic (2.1%, d.b.) [22Sriket 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: 1199-207.
[http://dx.doi.org/10.1016/j.foodchem.2006.10.039] ], but higher than those from traditional farm (1.6%, d.b.) [22Sriket 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: 1199-207.
[http://dx.doi.org/10.1016/j.foodchem.2006.10.039] ]. Araujo et al. [25Lira GM, Silva MCD, Silva KWB, et al. Avaliação da qualidade físico-química e microbiológica do camarão espigão (Xiphopenaeus kroyeri, Heller, 1862) in natura e defumado. Bol Cent Pesqui Process Aliment 2013; 31(1): 151-60.
[http://dx.doi.org/10.5380/cep.v31i1.32717] ] also found a lower ash content (1.5%, d.b.) than those found in the present study, however, it should be noted that these authors analyzed the meat without the exoskeleton. Gonçalves & Gomes [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.] developing a value added product with L. vannamei, also found lower ash content (1.6% d.b. fresh shrimp and 1.2% d.b. breaded shrimp). This difference of percentages can be justified because of the presence of the exoskeleton (from the first segment follow up to the telson). In addition, the exoskeleton of crustaceans is composed basically of calcium carbonate, which can lead, therefore, to a higher ash content. For the stuffed shrimp, the ash content found was lower (1.24%, d.b.) and statistically different (p<0.05) compared to the fresh one, but closer to that found by Gonçalves & Gomes [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.], for breaded shrimp.

The pH drops statistically (p<0.05) from raw fresh shrimp (7.7) to the stuffed shrimp (6.4) and can be associated to the increment of cream cheese, which according to Phadungath [28Brazil. Ministério da Agricultura, Pecuária e Abastecimento (MAPA). Decreto n° 9.013, de 29 de março de 2017, aprova o novo Regulamento de Inspeção Industrial e Sanitária de Produtos de Origem Animal – RIISPOA. Brasília, DF: Diário Oficial da União, 30/03/2017, Seção 1, No 62 3-27.] states that the cream cheese pH is between 4.4 and 4.9. Despite the drop in pH, the results is in accordance with the pH limited as a parameter of freshness by Brazilian legislation [29Soares KMP, Gonçalves AA. Qualidade e segurança do pescado. Rev Inst Adolfo Lutz 2012; 71(1): 1-10.] for raw fresh shrimp (7.85) and also, corroborated with the low values of TBVN and TMA (and without statically difference, p>0.05, between fresh and stuffed shrimp), being also in accordance with the current legislation. It is emphasized that the shrimp was treated with sodium metabisulfite immediately after slaughter and with the food grade humectant additive (STPP) during the processing, which may result in a slight increase in pH value. In addition, the way in which shrimp is handled, from capture to consumer arrival, determines the intensity with which they present the enzymatic, oxidative and microbiological changes [2Gonçalves AA. Tecnologia do pescado: Ciência, tecnologia, inovação e legislação, Atheneu, São Paulo, SP, Brazil 2011; 608., 30Honda SN. Avaliação microbiológica do camarão da Amazônia (Macrobrachium amazonicum) e sua relação com o ambiente de criação na carcinicultura. Master Thesis (Mestrado em Aquicultura Universidade Estadual Paulista), Jaboticabal, SP, Brazil 2012; 66.]. The speed with which each of these changes develops depends on how the basic principles of conservation, hygiene, cold chain and capture methods were applied [2Gonçalves AA. Tecnologia do pescado: Ciência, tecnologia, inovação e legislação, Atheneu, São Paulo, SP, Brazil 2011; 608.]. In the present study, all hygienic-sanitary care was done thinking mainly about the quality of the final product and the safety of the consumer.

No growth of microorganisms was observed in fresh raw and stuffed shrimp, demonstrating that all technological processes were carried out within the hygienic-sanitary standards since collection at the farm, guaranteeing the perfect cold chain along the transport, and handling, and the use of chlorinated water in each washing step. Honda [31Ribeiro SCA, Tobinaga S. Avaliação sensorial de filés de matrinchã (Brycon cephalus) processados por métodos combinados. Rev Bras Prod Agroind 2002; 4(2): 101-6.
[http://dx.doi.org/10.15871/1517-8595/rbpa.v4n2] ] states that inadequate storage temperature during transportation, storage, and marketing contributes greatly to the multiplication of microorganisms present in shrimp. In addition, the use of gloves, masks by the manipulators, as well as the hygiene of utensils and workbench, and the use of sodium metabisulphite after the slaughter, and the brining process (NaCl + STPP) corroborated with the result and leave the product apt and safe for consumption (sensory analysis) and suitable for later storage (shelf life study).

The average score in the Hedonic Scale for the stuffed shrimp was 8.72 which represents the scale between “I liked very much” and “I liked it extremely”. Eighty-six percent were attributed as “I liked extremely”, demonstrating an excellent acceptability, which corroborates with the Acceptability Index (AI) calculated of 96.9% (excellent acceptance of the product among the tasters). This result was higher when compared to those value-added products found in the literature: butterfly breaded shrimp (87.8%) [11Gonçalves AA, Gomes PA. Desenvolvimento de um produto de valor agregado: camarão empanado corte butterfly. Revista Brasileira de Engenharia de Pesca 2008; 3(1): 62-75.], and smoked fish fillets (82.2%) [32Fernandes TM, Silva JA, Silva AHA, Cavalheiro JMO, Conceição ML. Flour production from shrimp by-products and sensory evaluation of flour-based products. Pesqui Agropecu Bras 2013; 48(8): 962-7.
[http://dx.doi.org/10.1590/S0100-204X2013000800022] ]. On the other hand, Fernandes et al. [33Teixeira LV. Análise sensorial na indústria de alimentos. Rev Inst Laticínios Cândido Tostes 2009; 366(64): 12-21.] evaluating the cake made with shrimp cephalothorax meal showed medium acceptance, with average scores above 7.0 (“I liked moderately”). Despite the divergence between acceptance values found in the literature for several products, the product acceptance varies with living standards and cultural basis, and demonstrates the consumer's reaction to various aspects, such as price, age, hygiene, place of consumption, and not only if whether or not it pleased the product [33Teixeira LV. Análise sensorial na indústria de alimentos. Rev Inst Laticínios Cândido Tostes 2009; 366(64): 12-21., 34Zhang Z, Xiao L, Lou Y, et al. Development of a multiplex real-time PCR method for simultaneous detection of Vibrio parahaemolyticus, Listeria monocytogenes and Salmonella sp. in raw shrimp. Food Control 2015; 51: 31-6.
[http://dx.doi.org/10.1016/j.foodcont.2014.11.007] ]. In this sense, the purchase intention for stuffed shrimp corresponded to 82% (“Surely I would buy”), going to 14% (“Probably I would buy”) and 4% (“Maybe I would buy / maybe I would not buy”). The percentage of 82% (“surely I would buy”) indicated that the product was well accepted by consumers, suggesting that there is potential for marketing.

The microbiological analysis of food is a prerequisite for microbial safety management [35Tsironi T, Dermesonlouogloua E, Giannakouroua M, Taoukis P. Shelf life modeling of frozen shrimp at variable temperature conditions. Food Sci Technol (Campinas) 2009; 42(2): 664-71.]. As expected, the results of the microbiological analyzes showed absence of the analyzed microorganisms (total mesophilic and psychrophilic counts, Salmonella sp., coagulase positive staphylococci and thermotolerant coliform) at the beginning of storage (Time Zero), and remained unchanged throughout the evaluated period, demonstrating that the hygienic-sanitary quality at the beginning of the study corroborated with its subsequent microbiological stability throughout the 180 days of storage.

The results of the physico-chemical analyze of the stuffed shrimp along the 180 days of storage (-18°C) are presented in Table 4. No significative difference (p>0.05) was observed in all parameters evaluated during the 180 days of storage. The pH values for the stuffed shrimp remained stable throughout the storage period, and below the legal limits [29Soares KMP, Gonçalves AA. Qualidade e segurança do pescado. Rev Inst Adolfo Lutz 2012; 71(1): 1-10.] for shrimp freshness (7.85), which corroborates with the results of the lower TVBN, TMA and microbiological analyzes; however, differed from the results of the shelf life of frozen shrimp (Macrobrachium rosenbergii) at different temperatures: the initial pH of 6.95 increased to 7.93 (-12°C) in 39 days and after to 7.85 (-15°C) in 74 days [36Kirschnik PG, Viegas EMM. Alterações na qualidade do camarão de água doce Macrobrachium rosenbergii durante estocagem em gelo. Food Sci Technol (Campinas) 2004; 24(3): 407-12.
[http://dx.doi.org/10.1590/S0101-20612004000300019] ].

The results for TVBN and TMA remained stable over the storage period, and below the legal limits for freshness, i.e., <30 mg / 100g and <5 mg / 100g, respectively. According to Soares & Gonçalves [30Honda SN. Avaliação microbiológica do camarão da Amazônia (Macrobrachium amazonicum) e sua relação com o ambiente de criação na carcinicultura. Master Thesis (Mestrado em Aquicultura Universidade Estadual Paulista), Jaboticabal, SP, Brazil 2012; 66.], the total volatile bases represent the set of nitrogenous bases, such as ammonia, trimethylamine, dimethylamine, monomethyl amine, putrescine, cadaverine and spermidine, normally present in deteriorated fish and, according to [37Hocaoglu A, Demirci AS, Gümüs T, Demirci M. Effects of gamma irradiation on chemical, microbial quality and shelf life of shrimp. Radiat Phys Chem 2012; 81(12): 1923-9.
[http://dx.doi.org/10.1016/j.radphyschem.2012.07.017] ], the production of TBVN during seafood storage is a result of the action of tissue enzymes and microbiological activity. Hocaoglu [38Oliveira VM, Freitas MQ, Clemente SCS, Mársico ET. Método do índice de qualidade (MIQ) desenvolvido para camarão (Litopenaeus vannamei) cultivado. Rev Cienc Vida 2009; 29(1): 60-71.] observed in frozen shrimp (-18°C) 12.33 mg/100g and Oliveira et al. [39Bono G, Gai F, Peiretti PG, et al. Chemical and nutritional characterisation of the Central Mediterranean Giant red shrimp (Aristaeomorpha foliacea): Influence of trophic and geographical factors on flesh quality. Food Chem 2012; 130(1): 104-10.
[http://dx.doi.org/10.1016/j.foodchem.2011.07.004] [PMID: 264342 69] ] observed 14.57 mg/100g. Tsironi et al. [36Kirschnik PG, Viegas EMM. Alterações na qualidade do camarão de água doce Macrobrachium rosenbergii durante estocagem em gelo. Food Sci Technol (Campinas) 2004; 24(3): 407-12.
[http://dx.doi.org/10.1590/S0101-20612004000300019] ] detected values of up to 25 mg/100g after eight months of frozen storage (-15°C), and Bono et al. [40Gonçalves AA. Produtos de valor agregado: Um desafio ou uma necessidade? Aquaculture Brasil 2018; 2018(11): 70-1.] observed results up to 86 mg/100g after eight months of storage. As the initial microbiological quality of the stuffed shrimp was excellent (i.e. absent), no degradative chemical changes from microorganisms during frozen storage can be achieved, which corroborated the physicochemical stability of the product throughout the storage time.

Table 4
Physico-chemical results of frozen stuffed shrimp stored at -18ºC for 180 days.