Freshness assessment of shrimp Metapenaeus affinis by quality index method and estimation of its shelf life

Abstract

This study aimed to develop a Quality Index Method (QIM) for ice stored Metapenaeus affinis, and estimate its shelf life of shrimp during 12 days of storage analyzing periodically microbiological (total mesophilic (TMC), psychrotrophilic (PTC), physicochemical (TVB-N, TMA, pH, TBARS and FFA), and sensory (Quality Index Method protocol) characteristics. Partial least squares (PLS) regression was used to correlate the QIM attributes, and linear regression analysis was used to check the variables as a function of storage time. Principal component analysis (PCA) was used for interpreting physicochemical and bacteriological quality parameters. The QIM scheme was developed based on 18 demerit points, in which zero indicates total freshness. From the integration of sensory, microbiological, and physicochemical data, it was possible to estimate that the shelf life of ice stored Metapenaeus affinis is 9 days.

Fish Quality Index Method: Principles, weaknesses, validation, and alternatives—A review

“…Thus, QIM could underestimate the shelf life of spiny lobster since the TVB-N value was below the acceptable limit on the 10th day. On the other hand, another recent study on monitoring crustacean shelf life showed that TVB-N levels increased up to 25 mg N/100 g after 10 days of storage, as described by Khodanazary (2019). TVB-N presented levels above 34 mg N/100 g in the ninth day of storage for shrimp (Metapenaeus affinis), as this index well correlated with the QIM results, since the sensory panel rejected the samples at the same day (Khodanazary, 2019).…”

“…On the other hand, another recent study on monitoring crustacean shelf life showed that TVB-N levels increased up to 25 mg N/100 g after 10 days of storage, as described by Khodanazary (2019). TVB-N presented levels above 34 mg N/100 g in the ninth day of storage for shrimp (Metapenaeus affinis), as this index well correlated with the QIM results, since the sensory panel rejected the samples at the same day (Khodanazary, 2019). Moreover, the correlation of QIM with the TVB-N values becomes problematic when considering freshwater species, due to the absence of TMAO in vivo.…”

“…Therefore, to evaluate the influence of the different analyses conducted by the assessors and confirm the QIM results and correlate sensory rejection with predicted shelf life, effective statistical models should be employed, mainly multivariate analysis, focusing on describing QIM's performance and understanding the outcomes. In addition, some authors have also applied diverse chemical and bacteriological analyses in order to validate the results (Ahmadi Shalhe et al, 2018;Alasalvar et al, 2002;Bogdanović et al, 2012;Borges et al, 2013Borges et al, , 2014Khodanazary, 2019; Li et al, 2017).…”

“…These results demonstrate that the sensory analysis of the QIM underestimates the microbiological analysis, leading to discarding fish that is able for consumption. Inversely, Khodanazary (2019) assessed the freshness of shrimp (Metapenaeus affinis). These authors found that the QIM indicates that the shelf life in ice stored was 9 days and the total mesophilic count of Metapenaeus affinis reached 7 log CFU/g before the ninth day (Khodanazary, 2019), which is higher than the maximal recommended (ICMSF, 1986).…”

“…Moreover, the bacteriological validation showed controversial results (Baixas-Nogueras, Bover-Cid, Veciana-Nogues, Nunes, & Vidal-Carou, 2003;Sant'Ana, Soares, & Vaz-Pires, 2011), which limits its use as an official method for fish quality assessment. Although recent studies have shown QIM to be a useful device (Ahmadi Shalhe, Khodanazary, & Hosseini, 2018;Ghani Kuvei, Khodanazary, & Zamani, 2019;Khodanazary, 2019), novel methods have been reported showing high performance and being precision tools (Hassoun & Karoui, 2015;Wu, Pu, & Sun, 2019). Notwithstanding, there is a lack regarding the correlation between the use of these novel methods and the sensory evaluation of fish.…”