Development and Application of the Quality Index Method (QIM) for Farmed Tambaqui (Colossoma macropomum) Stored Under Refrigeration

Abstract

This research aimed to assess the freshness of farmed tambaqui (Colossoma macropomum) eviscerated and stored in ice for 30 days. The changes observed in the fish over storage were monitored through sensory evaluation Quality Index Method (QIM), pH, total volatile basic nitrogen (TVB‐N), thiobarbituric acid reactive substances (TBARS), and microbiological analyses (coagulase‐positive staphylococcus, Salmonella spp., coliforms at 45C, and mesophilic and psychrotrophic bacteria counts). The Quality Index (QI) showed a linear increase, ranging from 0 (maximum freshness) to 34 (total loss of freshness), with a strong correlation (R2 = 0.988) with storage time. The microbiological analyses showed that the psychrotrophic bacteria count went over the recommended limit after the 26th day. TVB‐N ranged from 4.01 to 15.92 mg/100 g; pH, from 6.01 to 6.57; and TBARS, from 0.01 to 0.14 mg MDA/kg between the 1st and 30th days of storage. The sensory, physicochemical, and microbiological analyses established that eviscerated tambaqui stored in ice is appropriate for consumption up until the 22nd day. Practical Applications The QIM takes into account the diversity among species and defines the sensory quality parameters for fish freshness. Sensory analysis has been shown to be an important tool to assess sensory quality of fresh fish and is largely used by sanitary inspection agencies. The QIM established that eviscerated tambaqui (C. macropomum) stored in ice at 0C remained proper for consumption until the 22nd day. The results of the application of QIM to marketed fish species can establish the product's shelf life which is a very important for the industry and for consumers. QIM: Development and Application of a Sensory Protocol for Farmed Tambaqui (C. macropomum).

Tambaqui de tanque-rede: qualidade microbiológica, valor nutricional e rendimento

“…Cardoso, Tessari, Castro & Kanashiro (2001) noted that the water is the main source of coliform contamination in pisciculture. Araújo et al (2017) presented data on coliform counts observed in farmraised tambaqui which were similar to those obtained in the current study. However, they analyzed samples of farmed tambaqui raised in fish ponds, which had been gutted and stored under ice.…”

“…was observed in the samples analyzed in this study. Only one other study evaluating the quality of farm-raised tambaqui (gutted, washed with water containing 5 ppm chloride and stored under ice) could be found in the literature prior to the carrying out of this study; however, this was related to fish ponds (Araújo, Lima, Joele, & Lourenço, 2017). The authors reported results analogous to those obtained in this study regarding coagulase positive staphylococci.…”

“…However, they analyzed samples of farmed tambaqui raised in fish ponds, which had been gutted and stored under ice. The coliform counts for the samples reported in the cited reference were below 10³ UFC/g (Araújo et al, 2017). Santos et al (2018) evaluated the microbiological quality of 15 units of eviscerated caranha (Piaractusmesopotamicus) packed in ice collected in a processing unit.…”

Development of a quality index scheme and shelf-life study for whole tambaqui (Colossoma macropomum)

“…SEP was 1.184 for pacu (Borges et al 2013), 1.057 for tambacu (Borges et al 2014b) and 2.9 for eviscerated tambaqui (Araújo et al 2016), usually at intervals of up to 1 and 5 days. Cyprian et al (2008) developed a QI for arctic char, Salvelinus alpinus (Linnaeus), a freshwater fish, with results similar to those found in the present study: quality attributes and storage time had a high linear correlation and the SEP was only 1.48 (one day).…”

“…Recently, QI protocols have been developed for pacu, Piaractus mesopotamicus (Holmberg, 1887), with 32 demerit points and a shelf-life of 11 days (Borges et al 2013), for the hybrid tambacu, Colossoma macropomum x Piaractus mesopotamicus, with 26 demerit points and shelf-life of 11 days (Borges et al 2014b), and for the hybrid tambatinga, Colossoma macropomum x Piaractus brachypomus (Cuvier, 1818), with 18 demerit points and a shelf-life of 10 days . Tambaqui has a recently developed QI protocol for eviscerated fish, with 34 demerit points and a shelflife of 26 days (Araújo et al 2016). However, the whole fish (as it is traditionally marketed) has specific characteristics that lead to changes in sensory parameters over time, which require a specific protocol, not yet developed.…”