sodium-nitrite and 3-4-dihydroxyphenylethanol

Nitrite is widely used in meat products as a multifunctional additive, combining flavour and colour properties with antioxidant and antimicrobial effects. However, nitrite may form reaction products (i.e., nitrosamine) that are potentially carcinogenic to humans. The meat industry, in response to consumers' demands for nitrite-free products, is seeking natural alternatives to nitrite, such as plant-based extracts. Three types of dry-fermented sausages were manufactured: NIT, containing 30 ppm of sodium nitrite; GSE, containing grape seed extract and olive pomace hydroxytyrosol; and CHE, containing chestnut extract and olive pomace hydroxytyrosol. Next-generation sequencing (NGS) was used to analyse microbial consortia, which were correlated with physical and chemical parameters. The prokaryotic community composition was similar among treatments, with a high relative abundance of Staphylococcus xylosus and Lactobacillus sakei, collectively accounting for 87% of the total community. However, significant differences were observed in both operational taxonomic unit (OTU) presence/absence and relative abundance. Ten genera varied in abundance between treatments. The increase in Lactobacillaceae in CHE may explain the reduced pH levels detected in these samples. In conclusion, NGS analysis showed that the prokaryotic community composition was similar in GSE and NIT, while CHE varied in both the composition and relative abundance of different taxa.

Topics: Fermentation; Fermented Foods; Grape Seed Extract; Italy; Meat Products; Microbiota; Phenylethyl Alcohol; Sodium Nitrite

Dry-fermented pork sausages, from Cinta Senese local breed, were manufactured replacing sodium nitrite (NIT) with two mixtures of natural antioxidants consisting of: i) grape seed extract and olive pomace hydroxytyrosol (GSE); ii) chestnut extract and olive pomace hydroxytyrosol (CHE). The effects on physical-chemical, aromatic and sensory traits, as well as the microbiological safety, were tested. Nitrite replacement lowered the pH in GSE and CHE samples and resulted in several differences in physical traits between CHE and NIT samples. Listeria monocytogenes, Salmonella and Clostridium botulinum were not found in any samples. GSE and CHE mixtures showed a slightly lower antioxidant activity. Volatile profile showed a similar aromatic profile among the three treatments with differences mainly to abundance of the single compounds, indicating that replacement of nitrite by natural antioxidants did not affect the overall aroma profile, as outlined by olfactometry results. In addition, the replacement did not affect the overall acceptability, except for color-related traits, underscored in GSE and CHE products.

Topics: Animals; Antioxidants; Bacteria; Consumer Behavior; Fagaceae; Fatty Acids, Volatile; Fermentation; Food Handling; Food Preservation; Food Preservatives; Fruit; Grape Seed Extract; Humans; Lipid Peroxidation; Magnoliopsida; Meat Products; Odorants; Olea; Phenylethyl Alcohol; Plant Extracts; Seeds; Sodium Nitrite; Sus scrofa; Vitis