Manufacture Of Dry Fermented Sausages Research Articles

Influence of Common Reducing Agents on Technological Parameters of Dry-Fermented Sausages with Low Fat Content.

The production of dry-fermented sausages currently presents several challenges to be addressed: nutrition, health, sensory traits and technology are among the main issues that concern consumers and the meat industry. The objective of this study was to evaluate the effect of different reducing agents commonly used in the manufacture of dry-fermented sausages (salchichon type) with low fat content on the technological characteristics of the product. Four different reducing agents (ascorbic acid, a starter culture, sodium ascorbate and glucono-delta-lactone) were added to the meat batter to assess their impact on the physico-chemical traits, instrumental color, residual nitrates and nitrites and lipid oxidation of this meat product. High nitrate values were observed during both ripening and storage periods. All batches presented lipid oxidation values below the threshold that indicates meat rancidity. Adjustments of the original lean:fat proportion must be carried out on this low fat content sausage to obtain profitable results. Starter culture and sodium ascorbate have shown the best reducing and antioxidant activities among the additives studied. Once we have the technical design of the product, the next step will be oriented to identify the sensory characteristics in order to find a gap in the market.

Indigenous Microbiota to Leverage Traditional Dry Sausage Production.

The main issue addressed in this review is the need for innovation in the artisanal production of dry fermented sausages—leveraging rather than discarding tradition, together with some practical strategies available to achieve it. Throughout the text, emphasis is placed on the autochthonous microbiota responsible for the identity and unique sensory characteristics of these products. The available strategies to introduce innovation in this manufacturing process rely on metabolic flexibility of microbial strains. In this sense, this review evaluates the application of several tools aimed at improving the quality and safety of artisanal dry fermented sausages focusing on the microbial community role. The most studied alternatives to enhance dry sausage production comprise the use of autochthonous starter cultures—including functional and/or probiotic strains, the production of bacteriocins, and the generation of bioactive peptides, which have been thoroughly covered herein. The purpose of this work is to review recent research about novel different strategies available for food technologists to improve safety and quality in the manufacture of dry fermented sausages. Additional support strategies—quality product registers and innovation through tradition—have been suggested as complementary actions towards a successful introduction of indigenous microbial communities into traditional dry sausage production.

Effect of cranberry pomace on the physicochemical properties and inactivation of Salmonella during the manufacture of dry fermented sausages

The effect of cranberry pomace (CP) incorporation on S. enterica serovars inactivation, starter culture population, and physicochemical properties of sausages during the manufacture of dry fermented sausages (DFS) was studied. Sausages containing a five-strain cocktail of S. enterica serovars at 7-log CFU/g, with different levels of CP (control, 0%; low, 0.55%; medium, 1.70%; high, 2.25% wt/wt), or liquid lactic acid (0.33% vol/wt, LA) were subjected to typical fermentation and drying conditions. A significant (P < 0.05) reduction in initial pH was observed in all CP treatments on day 0 as a result of CP native acidity. All treatments except low CP showed a significantly lower pH than the control throughout the study. Water activity (aw) was not significantly affected by CP level during fermentation. However, sausages containing medium and high CP levels showed a significantly lower final product aw than the control. DFS with CP exhibited a significantly (P < 0.05) faster and greater Salmonella inactivation during the first 5 days; reduction rate and level directly correlated to CP level. In the presence of medium and high levels of CP, Staphylococcus spp. growth was suppressed, while Lactobacillus spp. and Pediococcus spp. exhibited a stimulatory response. All treatments except low CP had no significant effect on product chemical composition, and Moisture Protein ratio (MPr). Low CP level yielded DFS with a slightly higher (P < 0.05) moisture content and MPr. Medium and high CP levels resulted in darker, duller and redder DFS with a softer texture. Findings suggest that low CP levels can be utilized by DFS manufacturers as a natural functional ingredient to further minimize the risk associated with Salmonella during DFS production without altering final product characteristics.

Application of Lactobacillus paracasei LPC02 and lactulose as a potential symbiotic system in the manufacture of dry-fermented sausage

The purpose of this study was to evaluate how the incorporation of the probiotic culture Lactobacillus paracasei and the prebiotic lactulose in dry-fermented sausage affects the technological, microbiological and sensorial characteristics of the products. Four formulations were analyzed: CONT (without prebiotic or probiotic); PREB (with 2% lactulose); PROB (with 108 CFU/g of L. paracasei); and SYMB (with 2% lactulose and 108 CFU/g of L. paracasei). The functional ingredients did not affect (P > 0.05) the water activity, pH, moisture, acidity and lactic acid bacteria counts during ripening process. Lower (P < 0.05) residual nitrite values were observed in sausages added with probiotic (7.20 ± 1.32 mg NO2/kg) than in the other treatments (11.38 ± 3.21 mg NO2/kg). The proximate composition and the sensorial attributes were not affected (P > 0.05) by the treatments. A mean concentration of 2.16 ± 0.39% of lactulose was observed in PREB and SYMB sausages and a count of 7.59 ± 0.37 log CFU/g of L. paracasei was observe in PROB and SYMB sausages. The incorporation of lactulose and L. paracasei into this traditional meat product resulted in a potential probiotic and symbiotic salami, adding additional nutritional benefits for the consumer.

Comparison of the fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages

The study examined the relative fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages (DFS). Three separate batches of sausages containing a five-strain cocktail for each serogroup and uninoculated control were manufactured and subjected to identical fermentation, maturation and dry curing conditions. Changes in physicochemical properties and inoculated STEC numbers were enumerated during the DFS production stages and log reduction and log reduction rates were calculated. Inoculation of very high concentrations (8logCFUg−1) of STEC in the sausage batter did not significantly (P>0.05) affect the changes in the pH, aw, moisture, protein, fat content compared to the uninoculated DFS. There was a significant (P<0.05) reduction in counts within the 48h fermentation for all STEC serogroups inoculated by about 0.97- to 1.42-log units. However, during the sausage maturation stage, all serogroups except O121 and O45 showed a significant reduction in numbers. During the extended 34day drying stage, all STEC serogroups showed a significant reduction in counts reaching a 5-log reduction within 20 to 27days of drying. ANOVA of the log reduction rates revealed significant differences in the reduction rates among the STEC serogroups examined. During the fermentation stage, serogroup O45 had the highest reduction rate at 0.98-logCFUg−1day−1 which was significantly higher compared to all other STEC serogroups (P<0.05), while O26 was the most tolerant to the conditions encountered during the fermentation stage with a reduction rate of 0.49-logCFUg−1day−1. However, during the extended 34days drying stage all STEC serogroups showed a steady reduction in population with a reduction rate ranging from 0.11- to 0.18-logCFUg−1day−1. The log reduction rate of E. coli O157:H7 was similar to that of serogroups O111 and O103, but was significantly lower (P<0.05) than all other STEC serogroups examined in the study. The log reduction rates of serogroups O121, O45, O145 and O26 during drying were not significantly different (P>0.05) from each other. These results indicate that the lethality of DFS production processes observed against E. coli O157:H7 would result in a similar inactivation of the top six non-O157 STEC.

Characterization and Technological Features of Autochthonous Coagulase-Negative Staphylococci as Potential Starters for Portuguese Dry Fermented Sausages.

The manufacture of dry fermented sausages is an important part of the meat industry in Southern European countries. These products are usually produced in small shops from a mixture of pork, fat, salt, and condiments and are stuffed into natural casings. Meat sausages are slowly cured through spontaneous fermentation by autochthonous microbiota present in the raw materials or introduced during manufacturing. The aim of this work was to evaluate the technological and safety features of coagulase-negative staphylococci (CNS) isolated from Portuguese dry fermented meat sausages in order to select autochthonous starters. Isolates (n = 104) obtained from 2 small manufacturers were identified as Staphylococcus xylosus, Staphylococcus equorum, Staphylococcussaprophyticus, and Staphylococcus carnosus. Genomically diverse isolates (n = 82) were selected for further analysis to determine the ability to produce enzymes (for example, nitrate-reductases, proteases, lipases) and antibiotic susceptibility. Autochthonous CNS producing a wide range of enzymes and showing low antibioresistance were selected as potential starters for future use in the production of dry fermented meat sausages.

Effect of Combined Salt and Animal Fat Reductions on Physicochemical and Biochemical Changes During the Manufacture of Dry-Fermented Sausages

Reducing salt and fat contents in dry-fermented sausages could benefit consumer health. This study aimed to quantify, from an experimental design, the effects of salt and fat contents and combined salt and fat reductions on the time-course of several physicochemical (product weight loss, mean water activity and pH values) and biochemical (proteolysis, lipolysis and lipid and protein oxidations) parameters. Statistical analyses found that time, salt and fat contents had a very significant impact on weight loss and aw and that time and salt content (not fat content) had a significant impact on pH. Biochemical results indicated that proteolysis was salt-content-dependent and amplified by combined salt and fat reductions. Intensity of lipolysis was mainly dependent on fat content. Lipid and protein oxidations were more intense in higher-fat formulations. Combined salt and fat reductions in dry-fermented sausages increased acidification, weight losses and aw, leading to more proteolysis, less lipolysis and less oxidation. Sensory studies are now required to investigate consumer acceptability of these healthier sausages. However, the present results constitute a valuable set of data for helping professionals wishing to reduce salt and fat contents in dry-fermented sausages.

Contribution of enterococci to the volatile profile of slightly-fermented sausages

The volatile profiles of slightly-fermented sausages inoculated with eight different enterococci strains were determined and compared with a fermented sausage manufactured without any inoculation. The volatile profile was determined by solid-phase microextraction (SPME) and gas chromatography coupled to mass spectrometry (GC/MS). A total of 121 volatile and semi-volatile compounds were identified in the samples of the final products (day 21). Terpenes from spices added during manufacture of dry-fermented sausages were the main group of compounds in the volatile profile. Other groups included alcohols (18% of total volatile compounds), aldehydes (16%), alkanes and alkenes (12%), and ketones (10%). These are derived from lipids, proteins or carbohydrates and formed during fermentation and ripening. In terms of global volatile composition, the batches inoculated with enterococci strains were similar to those obtained for non-inoculated batch. However, some quantitative differences in the volatile profiles of different batches were found, mainly in the compounds formed from amino acid catabolism (i.e.: propanol, isoamyl), from free fatty acid oxidation (i.e.: hexanal, hexanol), or from carbohydrate fermentation (i.e.: 2-butanone, acetoin). In comparison with non-inoculated sausages, some batches were more resistant to oxidation; they contained fewer volatile compounds arising from lipid oxidation. The use of different selected enterococci strains did not alter the volatile profile of slightly-fermented sausages. The enterococci strains provide similar volatile compounds to those usually reported in the literature.

Toxicological assessment of Penicillium nalgiovense strains for use as starter cultures in the manufacture of dry fermented sausages.

The use of fungal starter strains in the casing of dry fermented sausages allows standardization of the manufacturing process and ensures consumer safety. Penicillium nalgiovense is normally used for this purpose. Even though this species is reported as safe with respect to the production of the most common mycotoxins, its safety may be strain specific. The aim of the present work was to assess the toxicogenic potential of nine P. nalgiovense strains isolated from dry fermented sausages that were previously suitable as starters. The strains were tested for toxicity on brine shrimp larvae and the human cell line MCF7, for mutagenicity in the Ames test, and for antibacterial activity against gram-positive and gram-negative bacteria. According to our results, several P. nalgiovense strains were positive in more than one bioassay. Therefore, it is important to use different toxicological assays when characterizing strains intended for food use. Strains S1-2 and S14-4, which belong to biotypes 6 and 5, respectively, were nontoxigenic under the conditions tested. Overall, strain S1-2 of P. nalgiovense proved to be best suited as a starter in dry fermented sausage manufacture because in addition of being nontoxicogenic it produces white conidia, which is a desirable feature.

Short‐chain fructooligosaccharides as potential functional ingredient in dry fermented sausages with different fat levels

SummaryThe effects of short‐chain fructooligosaccharides (sc‐FOS) on colour, textural and sensory properties in dry fermented sausages have been studied. The sausages were manufactured with three different amounts of backfat (30%, 15% and 6%). The sc‐FOS was incorporated in a sufficient amount to constitute 2%, 4% and 6% of the initial mixture. Physico‐chemical parameters and microbiota evolution during ripening were not affected by the presence of this fibre. Colour parameters, especially lightness, decreased as the amount of sc‐FOS incorporated increased. However, the presence of sc‐FOS reduced hardness making the sausage easier to chew. Although all batches were well evaluated by the panellists, the higher acceptability was reported in batches with an intermediate fat level (15% of backfat). The results indicated that fibre could be suitable for use in the manufacture of dry fermented sausages

The influence of nitrite and nitrate on microbial, chemical and sensory parameters of slow dry fermented sausage

Nitrate and/or nitrite are used in the manufacture of dry-fermented sausages. However, research has mainly been focusing on nitrite and its effect on flavour development whereas little attention has been paid to nitrate. The aim of the present work was to study the effect of nitrate and nitrite as curing salts on the quality of a slow fermentation process. Two different batches containing nitrate or nitrite were manufactured. Microbial and chemical parameters were monitored during ripening and after vacuum packed storage, as well as their fatty acid composition and their profile of volatile compounds. The oxidation, measured as TBARS (Thiobarbituric acid reactive substances), was greater in the samples with added nitrite than in the samples with added nitrate. FFA (free fatty acids) release was higher in the samples containing nitrite throughout the process. Volatile compounds arising from amino acid degradation and carbohydrate fermentation were generated at higher levels in the samples with added nitrate, probably due to the higher population of microorganisms in these samples and the effect of nitrate on their metabolism.

Survival of Escherichia coli O157:H7 in dry fermented sausages containing micro-encapsulated probiotic lactic acid bacteria

Escherichia coli O157:H7 is capable of surviving the rigorous processing steps during the manufacture of dry fermented sausages. The effect of adding two probiotic organisms, Lactobacillus reuteri and Bifidobacterium longum as co-cultures with the meat starter cultures Pediococcus pentosaceus and Staphylococcus carnosus on the viability of E. coli O157:H7 in dry fermented sausages was studied. A 5 strain cocktail of E. coli O157:H7 was added at 7.4 log cfu/g to the sausage batter and challenged with either or both Lb. reuteri or B. longum before or after they were micro-encapsulated. Sausages were fermented at ⩽26 °C and 88% relative humidity (RH) followed by drying at 75% RH and 13 °C for 25 d. The pH, water activity ( a w), protein, moisture, and numbers of all inoculated organisms were monitored during processing. The pH and a w decreased from 5.7 and 0.98 to 4.9 and 0.88 at the end of fermentation and drying, respectively. These processes reduced E. coli O157:H7 by 1.0 and 0.7 log cfu/g at the end of fermentation and drying, respectively. Unencapsulated Lb. reuteri with or without B. longum reduced E. coli O157:H7 by 3.0 log cfu/g and B. longum caused a 1.9 log cfu/g reduction. While micro-encapsulation increased survival of Lb. reuteri and B. longum, it reduced their inhibitory action against E. coli O157:H7.

Use of bacterial extracts to enhance amino acid breakdown in dry fermented sausages

The effect of the intracellular cell-free extracts (ICFEs) of two bacterial strains ( Lactobacillus sakei GO and Bacillus pumilus) on the amino acid catabolism and the sensory properties of dry fermented sausages, was investigated. Extracts were added to sausages alone or in combination with a protease, papain. Amino acid breakdown was monitored by the changes in free amino acids, ammonia and amine content during the ripening process. A 15% decrease in the content of free amino acids was observed in sausages added with the ICFE from L. sakei GO. Furthermore, the extract of L. sakei GO significantly reduced (54–68%) the content of the amino acids considered as precursors of the typical ripened flavour, i.e., valine, leucine and isoleucine. Chemical changes were not reflected in a significant improvement of the sensory quality of sausages added with the ICFEs. The potential use of the bacterial ICFEs studied in the present work for the manufacture of dry fermented sausages, and its comparison with the use of fungal extracts, are discussed.

Improvement of the sensory properties of dry-fermented sausages by the addition of free amino acids

The addition of free amino acids in the manufacture of dry-fermented sausages, as a method to enhance their flavour, was evaluated. For this purpose, three batches of dry-fermented sausages were manufactured: a control batch (C), and the same formula treated with 0.159% (g/100 g sausage) of a mixture of valine, isoleucine and leucine (58/35/66) (w/w) (batch L1) or treated with 1.01% of a “pool” of free amino acids (batch L2) (gly/asn/his/arg/thr/ala/pro/tyr/val/met/ile/leu/phe/trp/lys/asp/glu/ser /gln/cys) (19/19/105/41/55/ 69/90/10/58/27/35/66/35/62/110/56/106/18/19/10) (w/w). The pH values, dry matters and water activities of experimental sausages did not show significant differences ( p < 0.05) among different batches. However, an increase in the microbial counts (lactic acid bacteria and micrococci) and in the level of free amino acids and ammonia was observed in batches L1 and L2. A higher amount of volatile compounds was also detected in both experimental batches (L1 and L2), particularly those compounds derived from amino acid breakdown, such as branched aldehydes and their corresponding alcohols. In the sensory analysis, bach L1 showed a better overall quality than the control and batch L2.

Effect of Debaryomyces spp. on the proteolysis of dry-fermented sausages

The effect of the addition of Debaryomyces spp. on the microbial, chemical properties and degradation of meat proteins in dry fermented sausages was investigated. The manufacture of dry fermented sausages with Debaryomyces spp. produced a slow decline in pH during early drying stage. However, the final product had lower ammonia, and higher acetic and d-lactic acids without producing any effect on the final pH. Sarcoplasmic proteins were not affected by Debaryomyces spp. but the degradation of myofibrillar proteins was accelerated at the beginning of the drying stage even though the final sausage, inoculated with Debaryomyces spp., had lower myofibrillar proteolysis. The content of free amino acids was similar at the beginning of the drying stage for all the studied batches. However, the high differences in the content of free amino acids at the end of the process could be attributed to the Debaryomyces spp. activity. The addition of a higher amount of Debaryomyces spp. did not contribute to a major proteolysis degree.

Effect of curing conditions and Lactobacillus casei CRL705 on the hydrolysis of meat proteins.

The effect of the common curing conditions used during the manufacture of dry fermented sausage on the proteolytic activity of Lactobacillus casei CRL705 against meat proteins was investigated. Hydrolysis of pork muscle sarcoplasmic and myofibrillar proteins was evaluated by SDS-PAGE and reverse phase-HPLC analysis. Ascorbic acid exerted a stimulatory effect on both sarcoplasmic and myofibrillar protein breakdown by Lact. casei CRL705 with the release of hydrophilic peptides and free amino acids, while NaCl and NaNO2 mainly stimulated myofibrillar degradation. Even when processing temperature (25 degrees C) did not positively affect bacterial protein hydrolysis, the presence of curing salts accounted for a remarkable increase in the non-volatile components that constitute taste-active compounds that strongly influence the final flavour of the product. To predict the suitability of Lact. casei CRL705 and its proteolytic enzymes as a starter culture for the dry processing of dry fermented sausages.

Mixed Starter Cultures To Control Biogenic Amine Production in Dry Fermented Sausages

Several combinations of an amine-negative Lactobacillus sakei strain, along with proteolytic Staphylococcus carnosus or Staphylococcus xylosus strains, were used to study the influence of mixed starter cultures on biogenic amine production during the manufacture of dry fermented sausages. Changes in pH, water content, proteolysis, microbial counts, and biogenic amine contents were simultaneously examined in a spontaneously fermented batch and in three mixed starter-mediated batches. A double-controlled microbial charge initially inoculated as mixed starter culture of L. sakei and Staphylococcus spp. (all amine-negative strains) drastically reduced tyramine, cadaverine, and putrescine accumulation. No production of other aromatic amines such as histamine, phenylethylamine, or tryptamine was observed in any batch. The polyamines, spermine and spermidine, were found in raw materials and their levels decreased slightly in the spontaneously fermented batch. No correlation between proteolysis and biogenic amine production was observed. The use of proper technological conditions favoring starter development and the use of the raw materials with good hygienic quality make it possible to produce fermented sausages nearly free of biogenic amines.

Technological and sensorial evaluation of Lactobacillus strains as starter cultures in fermented sausages

The performance of several lactobacilli strains isolated from naturally fermented sausages as starter cultures was evaluated. Microbiological, physical and chemical changes, in addition to sensorial aspects were studied. From the 12 different strains tested, 10 were capable of leading the fermentation in every batch throughout the process. The monitoring of the inoculated strains was easily carried out by plasmid profiles and by checking the pH rate drop of the sausages, which was slower for the non-inoculated lots. Treatment using natural fermentation resulted in a product where hydrogen sulphide odours, which could be related to the higher content of Enterobacteriaceae throughout the ripening process, diminished its overall acceptability. The lots seeded with different L. sake strains were found to be low in acid in sensory evaluation, correlating with a low lactic acid content. In contrast, the L. plantarum lot gave rise to an overacidified product related to having the highest amount of lactic acid at the end of the process. As a general rule lactobacilli strains isolated from meat origins are good candidates as starter cultures in the manufacture of dry-fermented sausages and produce satisfactory products depending on the specific strains used more than on the species.

Evaluation of Prerigor Freeze‐Dried Beef in the Manufacture of Dry Fermented Sausage

ABSTRACTExperiments were designed to determine the acceptability of prerigor freeze‐dried beef in the manufacture of dry fermented sausage. Several chemical and physical variables were measured on dry fermented sausages prepared using (1) prerigor salted, freeze‐dried, (2) prerigor unsalted, freeze‐dried, (3) postrigor salted, freeze‐dried, and (4) postrigor frozen beef as ingredients. Results showed that fat and moisture content, total shrinkage, Instron firmness and panel scores for juiciness, texture, and flavor were not affected to a large degree by treatment or rigor state of the beef ingredient. Generally, freezedried beef was found to be equal to conventional beef for dry sausage production regardless of when the freeze‐dried beef was salted.