Biological Silages from Tunisian Shrimp and Octopus By-Products

Abstract

Biological silages were prepared from shrimp head and octopus viscera by-products recuperated from the Tunisian seafood industry. Physical and biochemical changes and microbiological profiles were determined for raw materials during fermentation and on end products. Results A c c e p t e d M a n u s c r i p t 2 showed that biological silage significantly affected (P<0.05) moisture, protein, and ash contents of shrimp head (CSHS) and octopus viscera silages (COVS). CSHS and COVS were stable, and their final pH values were 4.31 ± 0.01 and 3.71 ± 0.00, respectively. Proteolysis activity was confirmed by a significant increase (P<0.05) of soluble nitrogen and low molecular weight of protein (<260 Da) found on the end products for both silages. Lipid oxidation was delayed by addition of 150 ppm ethoxyquin to the raw material prior to fermentation. Biogenic amines detected in raw shrimp and octopus samples decreased significantly (P<0.05) during the silage process. Histamine and tyramine, detected at high levels on octopus viscera, were absent in the end products. Tyramine was produced in CSHS, indicating the possibility of the bacterial decarboxylation of tyrosine. Microbiological profiles showed that both silage products were free from pathogenic and spoilage bacteria. Therefore, biological silage can be used as a conservation procedure of shrimp and octopus by-products. The storage period could be shorter than 30 days, and further analysis should be carried out to ascertain safety and nutritional value of silage products.

Shrimp head autolysis and use of protein-rich fraction for salted snacks enrichment

“…This is the case of the flours produced by Fernandes et al (2013), which did not contain Salmonella and have total coliform and Staphylococcus counts below the standards. The absence of pathogenic germs and enterobacteria was reported by Harrabi et al (2016) in shrimp by-products. In terms of microbiology, shrimp heads are suitable for human consumption.…”

Ensilados químicos y biológicos. Una alternativa de aprovechamiento integral y sustentable de los residuos pesqueros en la Argentina

“…Varios autores trabajaron en la utilización de subproductos pesqueros con distintas combinaciones de bacterias ácido lácticas y fuentes de carbohidratos para producir EB, obteniendo productos con alto valor nutricional (Tabla 4). Utilizaron diferentes bacterias ácido lácticas como Lactobacillus plantarum (Vázquez et al 2010;Góngora et al 2012;Khodanazary et al 2013;Vásquez Zuluaga 2015;Ortega Toro y Hoyos Concha 2016;Sánchez Trujillo et al 2016;Fernández Herrero et al 2017b, 2017c, 2019aHarrabi et al 2017;Perea Román et al 2017); Lactobacillus spp. (Cipriano Salazar et al 2015); bacterias del yogur, Lactobacilus casei, Lactobacilus acidofilus, Lactobacillus bulgaricus y Streptococcus thermophilus (Sesto 2010;Spanopoulos et al 2010;Fernández Herrero et al 2011, 2013, 2015a, 2015b, 2015cLlanes Iglesias et al 2012;Gama Ortiz 2013); Pedioccoccus acidilactici y Enterococcus faecium (Rai et al 2010) entre otros.…”

“…al. 2011;Góngora et al 2012;Fernández Herrero et al 2015b, 2015c, 2017b, 2017c, 2019aHarrabi et al 2017;Ramírez Ramírez et al 2018;Lopes de Lima et al 2020), miel (Sesto 2010Fernández Herrero et al 2011, 2013…”