Role of surface-inoculated Debaryomyces hansenii and Yarrowia lipolytica strains in dried fermented sausage manufacture. Part 1: Evaluation of their effects on microbial evolution, lipolytic and proteolytic patterns

The aim of this work was to study the effects of Debaryomyces hansenii and Yarrowia lipolytica strains, used with lactic acid starter cultures (Lactobacillus plantarum), on the manufacture of dried fermented sausages to understand their role on sausage microbial evolution, lipolytic and proteolytic patterns. The inoculation of the yeast strains did not markedly affect the sausage’s microbial flora. The sausages with the yeast strains showed more marked and earlier water activity (a_w) reductions. Moreover, the surface inoculation of the yeast strains resulted, at the end of ripening, in more pronounced proteolysis and lipolysis. The lipolytic patterns of the products were affected not only by the yeast strain but also by the level of mincing of the meat mixture used.     

Effect of wine addition on microbiological characteristics,volatile molecule profiles and biogenic amine contents in fermented sausages

The aim was to evaluate the effect of wine addition during manufacturing of dry fermented sausages, in terms of safety aspects (biogenic amine accumulation), aroma profile and sensory characteristics. Three batches of salami were produced: without wine addition and with 7.5% or 15% (v/w) of white wine. The fermented sausages showed characteristics that can increase product diversification. Some of the sensory features (i.e. increased salty perception) can represent an important strategy because of the trend to reduce salt intake for health reasons. The presence of wine immediately reduced the pH and is a source of ethanol, which can have an inhibitory effect against undesirable microflora. The microbiological results observed regarding Enterobacteriaceae and enterococci were encouraging. The addition of wine did not negatively affect the ripening time or increase the presence of biogenic amines. The samples containing wine showed reduced concentrations of putrescine.     

Chemical and microbiological characterization of alheira: A typical Portuguese fermented sausage with particular reference to factors relating to food safety

Alheiras are traditional smoked naturally fermented meat sausages produced in the north of Portugal. They have not previously been characterized as to their chemical and microbiological status. pH and salt levels are insufficient to assure microbiological safety, there is ample opportunity for post-cooking contamination; the products require chill storage and cooking before consumption.

Heavy metals and biogenic amines were, in general, within accepted limits for meat products. Lactic acid bacteria comprised the major microflora (ca. 7–8 log cfu/g) with substantial counts of micrococci and enterococci (up to 7 log cfu/g). Escherichia coli, Staphylococcus aureus and Listeria spp. were detected in several samples.     

Effect of starter culture, spice mix and storage time and temperature on biogenic amine content of dry fermented sausages

Two types of dry fermented sausage differing in spicing mixture and the diameter (low content of red pepper + diameter 80 mm, H-sausage; high content of red pepper + diameter 55 mm, P-sausage, respectively) were produced in parallel with two different starter cultures (Pediococcus pentosaceus + Staphylococcus carnosus, B-samples and S. carnosus + Staphylococcus xylosus + Lactobacillus farciminis, F-samples, respectively). The sausages were ripened 21 days and subsequently stored 91 days at the room temperature. Concentration of both most abundant amines, putrescine and tyramine (y; mg/kg DM) increased significantly (P<0.01) in HB-sausage during ripening (x; days): y=2.5+18.13x−0.3144x² (R²=0.99) and y=0.7+8.17x−0.1130x² (R²=0.99), and also during storage: y=127.3+5.123x (R²=0.79) and y=26.0+3.211x (R²=0.74), respectively. At the end of ripening, putrescine (247 mg/kg DM) and tyramine (123 mg/kg DM) content in the HB-sausage was higher (P<0.05) than in the PB-sausage (12 and 9 mg/kg DM, respectively), concentration of either of these amines was negligible (1 mg/kg DM) in either type of F-inoculated sausage. Both starter culture and sausage type influenced significantly (P<0.001) both putrescine and tyramine content in the sausage; starter accounted for 57% and 55% of total variability in putrescine and tyramine content, respectively. Due to the significant (P<0.05) increase of total aerobic counts in the HB-sausage between the end of ripening and the 7th day of storage, followed by the significant (P<0.01) increase of the sum of total biogenic amines between the end of ripening (425 mg/kg DM) and the end of storage (1029 mg/kg DM), the storage of the dry fermented sausages at the room temperature should not be recommended.     

Fish spoilage bacterial growth and their biogenic amine accumulation: Inhibitory effects of olive by-products

The antimicrobial effects of olive by-products (olive leaf extract, olive cake, and black water) on foodborne pathogens and fish spoilage bacteria isolated from anchovy, mackerel, and sardine were investigated. Total polyphenol contents in olive by-products were determined by the Folin–Ciocalteu procedure and their chemical composition was also evaluated by gas chromatography-mass spectrometry. The minimum inhibitory concentrations of olive by-product were performed using the broth microdilution method. Their impact on bacterial growth and biogenic amine production were also monitored in anchovy infusion decarboxylase broth. The total phenol content of olive cake and black water were 14.9 and 20.9 mg gallic acid/g extract, respectively. The major compounds were ethyl oleate (52.3%) and squalene (22.8%) in olive cake and palmitic acid (12.2%), phenanthrene (11.9%), and linoleic acid (11.4%) in olive leaf, while black water consisted of 51.1% squalene and 17.5% oleic acid ethyl ester. The minimum inhibitory concentration of olive leaf ranged from 0.78 to 25 mg/mL. Bacterial strains were more sensitive to olive leaf than other olive by-products. Bacterial load in anchovy infusion decarboxylase broth did not always correlate well with biogenic amine production. The effect of olive leaf, olive cake, and black water on biogenic amine accumulation varied depending on specific bacterial strains and biogenic amine. Olive cake and olive leaf generally had a stronger effect on reducing histamine accumulation by bacteria. Therefore, the results showed the potential effect of olive by-products in preventing or reducing the accumulation of histamine, which may beneficially affect human health.     

Effects of aw at packaging time and atmosphere composition on aroma profile,biogenic amine content and microbiological features of dry fermented sausages

The aim was to evaluate the effects of different water contents (corresponding to a_w 0.940, 0.914, 0.895 and 0.875) of sausages at different times on the characteristics of typical Italian dry fermented sausages packaged under two different modified atmospheres (MAP) (100%N₂ or 30%CO₂/70%N₂). During ripening and storage, samples were analyzed to evaluate pH and a_w changes, microbial population, biogenic amine (BA) accumulation and aroma profile.     

The effects of ripening period,nitrite level and heat treatment on biogenic amine formation of “sucuk” – A Turkish dry fermented sausage

The effects of ripening period (1–13 days), nitrite level (45–195 ppm) and heat treatment (30–90 °C) on biogenic amine formation of sucuk were investigated using the central composite rotatable design of response surface methodology.     

Micro-oxygenation and oak chip treatments of red wines: Effects on colour-related phenolics,volatile composition and sensory characteristics. Part II: Merlot wines

The character of Merlot wines after the treatments of micro-oxygenation and subsequent chips addition, as regards the colour-related phenolics, volatile composition and sensory characteristics, was studied. An increase in the degree of polymerisation of red pigments and a decrease in the value of the red component of the colour (a^*) and the degree of co-pigmentation were observed. The concentrations of monomeric anthocyanins and anthocyanin-derived pigments, such as hydroxyphenyl-pyranoanthocyanins and anthocyanin-ethyl-flavan-3-ol adducts, significantly decreased. With regard to the wine aroma, the micro-oxygenation produced a decrease of some esters, alcohols and benzenic compounds and increased some terpenes and C₁₃-norisoprenoids. With regard to sensorial analysis, micro-oxygenation treatment resulted in higher scores for the red fruit and spicy attributes and caused the presence of new attributes (nutty and sweet fruit). This technique produces a lower level of the typical oak chip aromas (vanilla and woody) in Merlot wines.     

Reducing salt level in food: Part 1. Factors affecting the manufacture of model cheese systems and their structure–texture relationships

A model lipoproteic matrix able to mimic hard-type cheese was produced with controlled structural and textural properties. Changes in the microstructural and rheological properties of these model cheeses made from different milk concentrate powder, anhydrous milk fat, salt contents and pH values at renneting were characterised. Rheological properties were measured by texture profile analysis, fat globule and protein aggregate size distributions by laser light scattering. Microstructural properties of the model matrices were studied by confocal laser scanning and scanning electron microscopy.Significant differences between the matrices were found for the structural, physico-chemical and rheological parameters measured. Cheeses with higher dry matter content were significantly harder and contained more insoluble proteins than cheeses with lower dry matter content. The salt concentration and the pH at renneting had significant influence on cheese hardness and adhesiveness of rheological parameters. The model lipoproteic matrix presented air bubbles and powder aggregates which could not be avoided during the manufacture of products. However, compared with classic cheese making with rennet or acid coagulation, the technology used here allows model cheeses to be produced rapidly with a good reproducibility of texture.     

Reduction of sodium and increment of calcium and ω‐3 polyunsaturated fatty acids in dry fermented sausages: effects on the mineral content,lipid profile and sensory quality

BACKGROUND: A combined technological approach was applied in the development of healthier dry fermented sausages: a partial substitution of the pork back fat by pre‐emulsified linseed oil and a partial replacement of sodium chloride with calcium ascorbate at two different levels, leading to low amounts of salt (14gSalt and 10gSalt, with 14 g and 10 g NaCl per kg of mixture, respectively). RESULTS: The developed products (14gSalt and 10gSalt) showed adequate results for a_w (0.85 and 0.87) and pH (4.98 and 5.21), and low lipid oxidation values (1.4 × 10^?4 and 1.5 × 10^?5 g malondialdehyde (MDA) kg^?1). The lipid modification led to a significantly higher supply of ω‐3 (23.3 g kg^?1) compared to the control (3.2 g kg^?1). Simultaneously, reductions of 38% and 50% in sodium content and a calcium supply of 4 and 5.2 g kg^?1 were achieved in the 14gSalt and 10gSalt formulations, respectively, compared to the control products (26 g salt and 0.87 g kg^?1 Ca). Instrumental analysis of colour and texture and sensory studies demonstrated that the organoleptic quality of the new formulations was similar to that of traditional products. CONCLUSIONS: The developed dry fermented sausages showed healthier properties than traditional ones owing to their reduced sodium and higher calcium content and a significant supply of ω‐3 fatty acids. © 2012 Society of Chemical Industry