Freshness Assessment and Shelf-Life Prediction for Seriola dumerili from Aquaculture Based on the Quality Index Method

Fish and fish-based products are easily perishable foods due to different factors, including fragile organization, abundant endo-enzymes, psychrophilic bacteria, and impact of pre-harvest operations, that contribute to reducing its value. Therefore, a timely effective method for fish freshness and shelf-life evaluation is important. In this context, this study aimed to develop a sensory scheme based on the Quality Index Method (QIM) (sensory table and point system) for freshness monitorization and shelf-life prediction for Seriola dumerili from aquaculture in Madeira Island. Evaluation of appearance, texture, eyes, and gills was performed during 20 days of storage on ice (0 ± 1 °C). The shelf-life prediction was supported by the analysis of microorganisms (total viable colonies, TVC, counts), texture (Torrymeter), and production of trimethylamine (TMA), evaluated by HS-SPME–GC–MS and validated according to Association of Official Analytical Chemists AOAC guidelines. The result is a QIM scheme with 25 demerit points, where zero indicates total freshness. From the integration of sensory analysis, microbial growth at the time of rejection (TVC, 108 cfu/cm2 and H2S producers, 107 cfu/cm2), texture (Torrymeter value < 8), and TMA analyses (>12.5 mg/100 g), shelf-life was estimated as 12 days (±0.5 days). The obtained results show the high-throughput potential of the developed method for fish freshness assessment and shelf-life prediction. This QIM scheme is a secure way to measure quality and provide users with a reliable standardized fish freshness measure.

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Acerola Fruit as a Possible Antimelanotic Agent in White Shrimp (Litopenaeus vannamei)

Journal of Food Processing ◽

10.1155/2015/460617 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Alex Augusto Gonçalves ◽

Adriene Rosceli Menezes de Oliveira ◽

Maria Rociene Abrantes

Keyword(s):

Shelf Life ◽

Inhibitory Activity ◽

Quality Index ◽

Bacterial Count ◽

White Shrimp ◽

Control Group ◽

Psychrophilic Bacteria ◽

Index Method ◽

Group A ◽

Sensory Analyses

This study aimed to testify acerola’s inhibitory activity on melanosis in farmed white shrimp (L. vannamei). Shrimp samples underwent immersion in different treatments (control group (C), metabisulphite solution group (M), and acerola solution group (A)). Quality Index Method (QIM) was used to measure the shrimp shelf life, during 21 days, where microbiological, chemical, and sensory analyses were performed at each 3 days. Groups C and A exceeded the limit of mesophilic bacterial count within 15 days of storage, and for M the period was 18 days. As for the psychrophilic bacteria, C and A both crossed the limit on day 12 and M on the 15th day. Group M had the highest TVBN and pH means, followed by A and lastly C. Yet, TMA analysis showed highest values in group C, second A, and finally M. Sensory analysis determined the shelf life of groups C, M, and A as 10.5, 14.6, and 12.3 days, respectively. There were not many significant differences between the groups in all analyses; hence, dipping shrimp in acerola solutions would not suffice to inhibit melanosis formation. Further studies are needed to fully determine acerola’s antimelanosic potential.

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