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Olive vegetation water (OVW) is a by-product with a noticeable environmental impact, however, its polyphenols may be reused food and feed manufacture as high-value ingredients with antioxidant/antimicrobial activities. The effect of dietary supplementation with OVW polyphenols on the gut microbiota, carcass and breast quality, shelf life, and lipid oxidation in broiler chickens has been studied. Chicks were fed diets supplemented with crude phenolic concentrate (CPC) obtained from OVW (220 and 440 mg/kg phenols equivalent) until reaching commercial size. Cloacal microbial community (rRNA16S sequencing) was monitored during the growth period. Breasts were submitted to culture-dependent and -independent microbiological analyses during their shelf-life. Composition, fatty acid concentration, and lipid oxidation of raw and cooked thawed breasts were measured. Growth performance and gut microbiota were only slightly affected by the dietary treatments, while animal age influenced the cloacal microbiota. The supplementation was found to reduce the shelf life of breasts due to the growth of spoilers. Chemical composition and lipid oxidation were not affected. The hydroxytyrosol (HT) concentration varied from 178.6 to 292.4 ug/kg in breast muscle at the beginning of the shelf-life period. The identification of HT in meat demonstrates that the absorption and metabolism of these compounds was occurring efficiently in the chickens.

Edible insects are increasing in popularity as a trendy new food item in many countries worldwide. However, little information is available regarding the associated foodborne pathogens, in particular, the spore-forming bacteria that may be present in these processed foods. In this study, mealworms, crickets, mole crickets and silkworms that are widely available online were investigated for microbial quality traits. Whereas water activity and pH results revealed a stable product, microbiota characterisation highlighted wide variability among the analysed insect species. Among the microbial targets considered in this study, total viable count, total aerobic spores and Bacillus cereus count were the most suitable for describing the food safety and microbial quality of these products. Endospore-forming bacteria ascribed to the B. cereus group were identified with genetic methods and putative virulence patterns. Three major clusters were delineated according to the phylogenetic analysis of the B. cereus group: B. cereus, B. thuringiensis and B. cytotoxicus, with virulence patterns particular to the enterotoxin genes found in each cluster. This work represents a first step in the hazard identification of B. cereus group bacteria isolated from edible insects. The presented results should also be considered with respect to domestic handling and rehydration of such products prior to consumption.

An appropriate seafood origin identification is essential for labelling regulation but also economic and ecological issues. Near infrared (NIRS) reflectance spectroscopy was employed to assess the origins of cuttlefish caught from five fishing FAO areas (Adriatic Sea, northeastern and eastern central Atlantic Oceans, and eastern Indian and western central Pacific Oceans). A total of 727 cuttlefishes of the family Sepiidae (Sepia officinalis and Sepiella inermis) were collected with a portable spectrophotometer (902–1680 nm) in a wholesale fish plant. NIR spectra were treated with standard normal variate, detrending, smoothing, and second derivative before performing chemometric approaches. The random forest feature selection procedure was executed to select the most significative wavelengths. The geographical origin classification models were constructed on the most informative bands, applying support vector machine (SVM) and K nearest neighbors algorithms (KNN). The SVM showed the best performance of geographical classification through the hold-out validation according to the overall accuracy (0.92), balanced accuracy (from 0.83 to 1.00), sensitivity (from 0.67 to 1.00), and specificity (from 0.88 to 1.00). Thus, being one of the first studies on cuttlefish traceability using NIRS, the results suggest that this represents a rapid, green, and non-destructive method to support on-site, practical inspection to authenticate geographical origin and to contrast fraudulent activities of cuttlefish mislabeled as local.

Vibrio parahaemolyticus is an emerging foodborne pathogen in the Mediterranean, usually associated with shellfish consumption. The increase in the number of outbreaks in Europe is primarily associated with the global warming of the ocean that has a great impact on the spread and genetic selection of waterborne pathogens. The primary role of Italy in Europe's mollusk production, together with the fact that cases of infections with V. parahaemolyticus are not always notified to the European community, highlighted the necessity of acquiring new information about the epidemiological involvement of shellfish products.The aim of the study was to provide useful insights into the first steps of the Risk Assessment associated with V. parahaemolyticus through the molecular characterization of isolates from commercialized mollusks.A total of 102 strains identified as V. parahaemolyticus were investigated as part of a larger sampling (1-year survey) from several shellfish species collected from the Venice lagoon and the North Adriatic sea. All strains were characterized by multilocus sequence typing and tested for the presence of virulence genes (trh and tdh). The study of sampling/environmental factors and epidemiological analyses was performed to describe the behaviors of the different genetic populations.The population structure analysis highlighted three genetic clusters that could be subject to temperature selection during cold (≤15°C) and warm (16°C) seasons. Moreover, other factors, such as molluscan species (clams/mussels), probably played a role in the distribution of genetic clusters. Although few strains carried the virulence factors (n = 6 trhThis work provides a useful background on the genotype spread as a first step in the Hazard Identification in light of future climate changes.

Due to its chemical properties, honey does not foster the growth of microorganisms, however it may contain a rich microbial community, including viable, stressed, and not viable microbes. In order to characterize honey microbiota focusing on the difference between products from beekeepers and large retail in the present study a culture-independent approach based on DNA metabarcoding was applied. Honey samples were collected from Local Beekeepers (LB) and Market sales (M) during four years with the aim to investigate the microbiological quality in the honey market. Extraction and amplification of DNA from honey samples showed reduced efficiency with increasing age of honey, with the loss of 50-80% of samples four years old (2014). For this reason, only samples of similar age were compared and the analysis of microbial communities focused on year 2017, for a total of 75 samples. Differences in alpha and beta-diversity were evidenced comparing microbial communities between LB and M samples. In particular, contaminant bacteria dominated the microbiota in M samples while LB samples were enriched in Lactic Acid Bacteria (LAB) that cannot be isolated with culture-dependent approaches.

Near infrared spectroscopy (NIRs) and ultraviolet visible spectroscopy (UV-vis) have been investigated as rapid techniques to characterize foodborne bacteria through the analysis of the spectra of whole cells or microbial suspensions. The use of spectra collected from broth cultures could be used as a fingerprint for strain classification using a combined polyphasic approach. The aim of this study was to evaluate the feasibility of NIRs and UV-vis for the characterization of blue strains belonging to the Pseudomonas fluorescens group. The bacteria were isolated from different food matrices, including some spoiled samples (blue discoloration). Eightyone strains previously identified at the species level were grown in Minimal Bacterial Medium broth under standard conditions at 22°C. Two biological replicates were centrifuged in order to separate the bacterial cells from the extracellular products. Six aliquots per strain were analyzed on a small ring cup in transflectance mode (680-2500 nm, gap 2 nm). A subset of 39 strains was evaluated by UV-vis to determine changes in the spectral characteristics at 48 and 72 hours. Several chemometric approaches were tested to assess the performance of NIRs and UVvis. According to the variable importance in projection (VIP), the 1892-2020 nm spectral region showed the highest level of discrimination between blue strains and others. Additional information was provided in the 680-886 and 1454-1768 nm regions (aromatic C-H bonds) and in the 2036-2134 nm region (fatty acids). Changes in UV-vis spectral data (at 48 and 72 hours) appear to indicate the presence of phenazine and catecholic compounds in extracellular products.

Vibrio is a very diverse genus that is responsible for different human and animal diseases. The accurate identification of Vibrio at the species level is important to assess the risks related to public health and diseases caused by aquatic organisms. The ecology of Vibrio spp., together with their genetic background, represents an important key for species discrimination and evolution. Thus, analyses of population structure and ecology association are necessary for reliable characterization of bacteria and to investigate whether bacterial species are going through adaptation processes. In this study, a population of Vibrionaceae was isolated from shellfish of the Venice lagoon and analyzed in depth to study its structure and distribution in the environment. A multilocus sequence analysis (MLSA) was developed on the basis of four housekeeping genes. Both molecular and biochemical approaches were used for species characterization, and the results were compared to assess the consistency of the two methods. In addition, strain ecology and the association between genetic information and environment were investigated through statistical models. The phylogenetic and population analyses achieved good species clustering, while biochemical identification was demonstrated to be imprecise. In addition, this study provided a fine-scale overview of the distribution of Vibrio spp. in the Venice lagoon, and the results highlighted a preferential association of the species toward specific ecological variables. These findings support the use of MLSA for taxonomic studies and demonstrate the need to consider environmental information to obtain broader and more accurate bacterial characterization.

The genus Aeromonas comprises ubiquitous bacteria that are known to play several roles in the environment. These bacteria were first described as fish pathogens, but their presence was documented in other reservoirs, such as animals and humans. Today, these bacteria are described as emerging pathogens, but their effective role in human pathogenicity is still controversial. In addition, their taxonomy is heavily debated, as species distinction is often difficult to achieve. To study the interspecies relationships and to investigate their connection with the environment, a multilocus sequence typing scheme previously developed for Aeromonas spp. was applied to 258 strains, and the genetic data were analysed by population software. Sampling was a fundamental step, including several of the main sources of Aeromonas: fish, food products and human cases of disease. The objective was to characterize the isolates and to find potential associations among them according to the following: species, sharing of virulence factors, source and adaptation to a specific habitat. The strains were characterized and demonstrated exceptionally high nucleotide variability in the Aeromonas genus. Among the sampled sources, different species distributions were found, highlighting the occurrence of adaptation processes towards specific habitats.

Phenols are plant metabolites characterised by several interesting bioactive properties such as antioxidant and bactericidal activities. In this study the application of a phenols concentrate (PC) from olive vegetation water to two different fresh products – gilt-head seabream (Sparus aurata) and chicken breast – was described. Products were treated in a bath of PC (22 g/L; chicken breast) or sprayed with two different solutions (L1:0.75 and L2:1.5 mg/mL; seabream) and then stored under refrigeration conditions. The shelf life was monitored through microbiological analyses – quality index method for seabream and a specific sensory index for raw breast. The secondary products of lipid-peroxidation of the chicken breast were determined using the thiobarbituric acid reactive substances (TBARs) test on cooked samples. Multivariate statistical techniques were adopted to investigate the impact of phenols and microbiological data were fitted by DMfit software. In seabream, the levels of PC did not highlight any significant difference on microbiological and sensory features. DMfit models suggested an effect only on H2S producing bacteria with an increased lag phase compared to the control samples (C: 87 h vs L2: 136 h). The results on chicken breast showed that the PC bath clearly modified the growth of Pseudomonas and Enterobacteriaceae. The phenol dipping was effective in limiting lipid-peroxidation (TBARs) after cooking. Treated samples disclosed an increase of shelf life of 2 days. These could be considered as preliminary findings suggesting the use of this concentrate as preservative in some fresh products.

Bacterial proteases are involved in food spoilage and shelf-life reduction. Among the bacterial proteases, a predominant role in spoilage of dairy products seems to be played by the thermostable metallo-protease AprX, which is produced by various strains of Pseudomonas fluorescens. Differences in AprX enzyme activity among different strains were highlighted, but the most proteolytic strains were not identified. In this study, the presence of the aprX gene was evaluated in 69 strains isolated from food matrices and 18 reference strains belonging to the P. fluorescens group, which had been previously typed by the multi locus sequence typing method. Subsequently, a subset of reference strains was inoculated in ultra-high temperature milk, and the expression of the aprX gene was evaluated at 22 and 6°C. On the same milk samples, the proteolytic activity was then evaluated through Azocasein and trinitrobenzenesulfonic acid solution assays. Finally, to assess the applicability of the former assay directly on dairy products the proteolityc activity was tested on industrial ricotta samples using the Azocasein assay. These results demonstrate the spread of aprX gene in most strains tested and the applicability of Azocasein assay to monitor the proteolytic activity in dairy products.

In the past, milk whey was only a by-product of cheese production, but currently, it has a high commercial value for use in the food industries. However, the regulation of whey management (i.e., storage and hygienic properties) has not been updated, and as a consequence, its microbiological quality is very challenging for food safety. The Next Generation Sequencing (NGS) technique was applied to several whey samples used for Ricotta production to evaluate the microbial community composition in depth using both RNA and DNA as templates for NGS library construction. Whey samples demonstrating a high microbial and aerobic spore load contained mostly Firmicutes; although variable, some samples contained a relevant amount of Gammaproteobacteria. Several lots of whey acquired as raw material for Ricotta production presented defective organoleptic properties. To define the volatile compounds in normal and defective whey samples, a headspace gas chromatography/mass spectrometry (GC/MS) analysis was conducted. The statistical analysis demonstrated that different microbial communities resulted from DNA or cDNA library sequencing, and distinguishable microbiota composed the communities contained in the organoleptic-defective whey samples.

Bacteriocins produced by some strains of lactic acid bacteria or antimicrobial casein fragments can be released into the water-soluble fraction of cheeses during ripening. However, there is a lack of experimental evidence which supports the theory that these peptides can exert an effective antimicrobial effect. The aim of this study was to investigate the anti-listerial activity of such peptides in Asiago d’Allevo cheese. The water-soluble fraction of Asiago was ultrafiltrated through 10 kDa cut-off membranes before being dialyzed (100–500 Da cut-off) to remove proteins, salts, and organic acids, prior to freeze-drying. The growth of Listeria innocua LRGIA 01 and of Listeria monocytogenes strain 162 in Brain Heart Infusion (BHI) at 30 °C in the presence or absence of 5 to 40 mg⋅mL−1 of cheese water-soluble extracts (WSEs) lyophilisate was monitored spectrophotometrically. WSEs lyophilisates from cheeses of different production systems (total mixed-ration-fed cows and cheese-making in a dairy plant in May; alpine-grazing cows and cheese-making in situ in July and September) and ripened for 6, 12, and 18 months were tested. A limited dose-dependent inhibition of growth was observed at all the assayed concentrations. The addition of cheese WSEs lyophilisates to BHI broth inhibited the growth of

The genus Aeromonas has been described as comprising several species associated with the aquatic environment, which represents their principal reservoir. Aeromonas spp. are commonly isolated from diseased and healthy fish, but the involvement of such bacteria in human infection and gastroenteritis has frequently been reported. The primary challenge in establishing an unequivocal link between the Aeromonas genus and pathogenesis in humans is the extremely complicated taxonomy. With the aim of clarifying taxonomic relationships among the strains and phenotypes, a multilocus sequencing approach was developed and applied to characterize 23 type and reference strains of Aeromonas spp. and a collection of 77 field strains isolated from fish, crustaceans, and mollusks. All strains were also screened for putative determinants of virulence by PCR ( ast , ahh1 , act , asa1 , eno , ascV , and aexT ) and the production of acylated homoserine lactones (AHLs). In addition, the phenotypic fingerprinting obtained from 29 biochemical tests was submitted to the nonparametric combination (NPC) test methodology to define the statistical differences among the identified genetic clusters. Multilocus sequence typing (MLST) achieved precise strain genotyping, and the phylogenetic analysis of concatenated sequences delineated the relationship among the taxa belonging to the genus Aeromonas , providing a powerful tool for outbreak traceability, host range diffusion, and ecological studies. The NPC test showed the feasibility of phenotypic differentiation among the majority of the MLST clusters by using a selection of tests or the entire biochemical fingerprinting. A Web-based MLST sequence database ( http://pubmlst.org/aeromonas ) specific for the Aeromonas genus was developed and implemented with all the results.

Carcass and flesh morphometric, reological and chemical traits of triploid (3n) and diploid (2n) shi drum (Umbrina cirrosa L.) were evaluated through 7 months. Three age groups, 17-, 21- and 24-month-old fish, were investigated. The effects of ploidy were statistically evaluated and the weight of fish was included in the model as a covariate because triploids grew less than diploids. As expected, fish weight was found to be significantly correlated with all the investigated morphometric traits, but showed a negative correlation with some chemical (pH) and colour traits (lightness) of raw fillet. In comparison with controls, triploid shi drums were characterized by different morphological traits that involved a slender body shape. In triploids, a reduction in condition factor, backbone weight, dressing index and an increase in the agility index were also recorded. When the commercial size (i.e. over 300 g) was achieved, triploids exhibited larger coelomatic and fillet (dorsal white muscle) fat deposition than diploids. Among reological traits, colour and texture were affected by ploidy; raw fillet lightness and cooked flesh tenderness were higher among triploids in all the investigated age groups. As fish were fed with a restricted feeding regimen, fillet fat deposition was supposed to be limited. Thus, the effects of ploidy on reological traits may be only partially explained by lipid fillet amount and are supposed to be more related to different fibre muscle architecture.

Dairy products are perishable and have to be preserved from spoilage during the food chain to achieve the desired shelf-life. Ricotta is a typical Italian soft dairy food produced by heat coagulation of whey proteins and is considered to be a light and healthy product. The shelf-life of Ricotta could be extended, as required by the international food trade market; however, heat resistant microflora causes spoilage and poses issues regarding the safety of the product. Next-generation sequencing (NGS) applied to the Ricotta samples defined the composition of the microbial community in-depth during the shelf-life. The analysis demonstrated the predominance of spore-forming bacteria throughout the shelf-life, mostly belonging to Bacillus, Paenibacillus and Clostridium genera. A strain involved in spoilage and causing a pink discolouration of Ricotta was isolated and characterised as Bacillus mycoides/weihenstephanensis. This is the first report of a food discolouration caused by a toxigenic strain belonging to the Bacillus cereus group that resulted the predominant strain in the community of the defective ricotta. These results suggest that the processing of raw materials to eliminate spores and residual microflora could be essential for improving the quality and the safety of the product and to extend the shelf-life of industrial Ricotta.

The aim of this study was to evaluate eight ultrasound (US) different combinations of amplitude (70 and 100%) and duration (50, 100, 200 and 300 s) for their lethal capacity against Escherichia coli , Pseudomonas fluorescens , Staphylococcus aureus and Debaryomyces hansenii , the generation of volatile compounds (VC) and their impact on milk sensorial descriptors. The strongest treatment (100% × 300 s) led to a population reduction of 4.61, 2.75, 2.09 and 0.55 log for D. hansenii , P. fluorescens , E. coli and S. aureus , respectively, but caused milk sensorial deterioration. Four descriptors (metallic, burnt, rubbery and sharp) were correlated with treatment duration. Each of them, using stepwise regression analysis, was found to be associated with one VC (dodecanoic acid, R 2 = 0.90; octanoic acid, R 2 = 0.82; δ-dodecalactone, R 2 = 0.81 and decanoic acid methyl ester, R 2 = 0.78) that could be considered as a marker for milk sensorial deterioration caused by US. Industrial relevance In this study it is stated in what conditions ultrasounds (US) could be used as effective sanitation procedure without the production of off-flavours and what is the inactivation capacity toward E. coli , P. fluorescens and D. hansenii in that conditions. Moreover, our results indicate possible markers of milk sensory degradation caused by US treatments. These markers (dodecanoic acid, octanoic acid, δ-dodecalactone and decanoic acid methyl ester) could be used to check milk sensory quality after US treatment instead of using expensive and time consuming sensory tests.

International audience; Listeria monocytogenes, agent of food-borne listeriosis, is a major concern in dairy industry. The aim of this study was to assess the occurrence of peptides inhibiting Listeria spp. growth in two traditional Alpine pressed-curd cheeses: Emmental de Savoie and Asiago d’Allevo, and to get further insights regarding the characteristics of these peptides. Water-soluble extracts of these two cheeses were ultrafiltered onto 10,000-g.mol−1 cut-off filters to remove proteins and the corresponding filtrate was subsequently dialysed with 100–500-g.mol−1 cut-off membranes to remove salt and organic acids. A decrease from 53 ± 2% to 68 ± 1% of Listeria innocua LRGIA01 cells growth after 12-h incubation at 30 °C was observed in the presence of lyophilised extracts of the four cheese samples which were analysed. A less pronounced inhibition of L. monocytogenes 162 strain cells growth by cheese extracts was observed under the same conditions. After ultrafiltration onto 1,000 g.mol−1 cut-off membranes, all the extracts had almost the same anti-L. innocua activity, suggesting that most of antibacterial peptides had a molecular mass between 100–500 and 1,000 g.mol−1. The assay of the anti-L. innocua activity of fractions of Asiago cheese extracts separated by cation-exchange chromatography indicated that non-cationic peptides had a lower antibacterial activity. Taken together, these data suggest that most of antibacterial peptides present in Asiago cheese are low molecular mass and cationic peptides. A significant contribution of intact bacteriocins is thus unlikely; a contribution of either antimicrobial fragments of bacteriocins or caseins released by proteolytic enzymes during cheese ripening is more likely.

The possibility of using near-infrared spectroscopy (NIRS) for the authentication of wild European sea bass ( Dicentrarchus labrax ) was investigated in this study. Three different chemometric techniques to process the NIR spectra were developed, and their ability to discriminate between wild and farmed sea bass samples was evaluated. One approach used spectral information to directly build the discrimination model in a latent variable space; the second approach first used wavelets to transform the spectral information and subsequently derived the discrimination model using the transformed spectra; in the third approach a cascaded arrangement was proposed whereby very limited chemical information was first estimated from spectra using a regression model, and this estimated information was then used to build the discrimination model in a latent variable space. All techniques showed that NIRS can be used to reliably discriminate between wild and farmed sea bass, achieving the same classification performance as classification methods that use chemical properties and morphometric traits. However, compared to methods based on chemical analysis, NIRS-based classification methods do not require reagents and are simpler, faster, more economical, and environmentally safer. All proposed techniques indicated that the most predictive spectral regions were those related to the absorbance of groups CH, CH(2), CH(3), and H(2)O, which are related to fat, fatty acids, and water content.

In the last decades, the number of animals shot in the Italian Alps during the regular hunting seasons has dramatically increased, which is particularly the case for wild ungulates. In these areas game is considered an important source of meat, and an increasing interest of consumers for game meat with high added value and favourable nutritional properties is noticeable (Hoffman and Wiklund, 2006). Nevertheless, targeted measures to assure game meat hygiene are still lacking in Italy, and much work is needed to convince hunters and consumers in general of the importance of this topic. This contribution summarises various complementary approaches to game meat hygiene, as initiated in the territory of the province Belluno, in the Italian Eastern Alps, i.e. the centre of the Dolomites, where red deer, roe deer, chamois, mouflon and wild boar are hunted.

The microbial community in milk is of great importance in the manufacture of traditional cheeses produced using raw milk and natural cultures. During milk curdling and cheese ripening, complex interactions occur in the microbial community, and accurate identification of the microorganisms involved provides essential information for understanding their role in these processes and in flavor production. Recent improvements in molecular biological methods have led to their application to food matrices, and thereby opened new perspectives for the study of microbial communities in fermented foods. In this study, a description of microbial community composition during the manufacture and ripening of Montasio cheese was provided. A combined approach using culture-dependent and -independent methods was applied. Culture-dependent identification was compared with 16S clone libraries sequencing data obtained from both DNA and reverse-transcribed RNA (cDNA) amplification and real-time quantitative PCR (qPCR) assays developed to detect and quantify specific bacterial species/genera (Streptococcus thermophilus, Lactobacillus casei, Pediococcus pentosaceus, Enterococcus spp., Pseudomonas spp.). S. thermophilus was the predominant LAB species throughout the entire ripening period of Montasio cheese. The culture-independent method demonstrates the relevant presence of Pseudomonas spp. and Lactococcus piscium at the beginning of ripening. The culture-dependent approach and the two culture-independent approaches produced complementary information, together generating a general view of cheese microbial ecology.

The aim of this study was to apply biometric measurements and analyses of proximate composition, fatty acid composition, and ratios of stable isotopes of carbon (δ(13)C) and nitrogen (δ(15)N) in muscle tissue to reliably differentiate between wild and farmed European sea bass (Dicentrarchus labrax). Farmed (n = 20) and wild (n = 19) European sea bass were purchased between March and May 2008 and used as standard samples. In the same months, a survey was conducted to evaluate the truthfulness of the statements on the labels of European sea bass sold in retail markets (declared farmed n = 34 and declared wild n = 33). In addition, data from the literature (reference) were employed to build the profile type of wild and farmed European sea bass. Primarily, an exploration and comparison of the analytical data of the standard data set based on principal component analysis and permutation test were performed. Afterward, an inferential statistical approach based on nonparametric combination test methodology (NPC) was applied on standard samples to check its suitability in discriminating the production method. This multivariate statistical analysis selected 30 variables on a total of 36 available. The validation of standard fish data set was accomplished by a novel nonparametric rank-based method according to profile type (just 1 misclassification over 39 samples). Both the NPC test and nonparametric rank-based method were then applied to survey fishes using the selected variables with the aim to classify the individual European sea bass as "true farmed" or "true wild". The former test segregated 10 fishes over 33 declared wild, whereas the results obtained by the nonparametric rank-based method showed that 11 of 33 declared wild European sea bass samples could be unquestionably attributed to the wild cluster. Moreover, considering the comparative contribution of profile type, a few surveyed farmed samples were ascribed to the wild cluster.

The effect of fat content and carbohydrate fat-replacers on the release of volatile odor compounds from beefburger, salami, and frankfurter has been investigated. The reduction in fat content in any of the three meat products studied resulted in a tendency toward an increase in the quantities of volatiles released in the headspace. Tapioca starch and maltodextrin appear to delay the release of certain classes of compounds selectively; for instance, tapioca starch appears to slow the release of some Maillard products while maltodextrin has a similar effect on terpenes. In contrast, oat fiber decreases the release of most of the compounds analyzed. Thus, the addition of carbohydrate fat-replacers to low-fat meat products could assist the flavor qualities of low-fat meat products by slowing down the release of odor compounds.

The relationship between extracted volatiles of Milano salami, one of the main dry-cured sausages produced in Italy, and their olfactory properties was studied. Volatile compounds were extracted by a purge-and-trap method, quantified using a flame ionisation detector and identified by mass spectrometry. Olfactory analysis was performed by sniffing the gas chromatographic effluent. Nearly 80 compounds were identified and quantified: most came from spices (60.5%), 18.9% from lipid oxidation, 11.8% from amino acid catabolism and 4.9% from fermentation processes. Panellists detected 19 odours by sniffing. These odours were associated with spices, lipid oxidation or fermentation and were in agreement with the contributions of each reaction to the overall aroma of the product.