Technological conditions influence aminogenesis during spontaneous sausage fermentation

The influence of two manufacturing processes on biogenic amine formation during the manufacture of Spanish dry fermented sausages of different diameters (fuet and llonganissa) was evaluated to elucidate which conditions allow better control of the aminogenic activity of spontaneous microbiota. Technological conditions affected both the amounts and the qualitative profile of biogenic amine accumulated. The higher processing temperature and relative humidity in process A (simulating those applied in industrial manufacture) favoured aminogenesis, since biogenic amine accumulation was faster and higher than in sausages manufactured under the process B (close to those used in traditional practices). The major amine differed depending on the diameter of the sausages, tyramine being the major amine in fuet (2.5 cm diameter sausage), and putrescine in llonganissa (4.5 cm). Moreover, sausages of higher diameter (llonganissa) had higher biogenic amine contents compared with the thinnest sausages (fuet). Conditions would modulate biogenic amine accumulation not only due to its influence on development of the bacterial population but also on its aminogenic activity. From the biogenic amine point of view, when sausages are spontaneously fermented, traditional lower temperatures and relative humidities are more appropriate than those usually applied in industrial processes.     

Strategies to reduce biogenic amine accumulation in traditional sausage manufacturing

Different strategies in the reduction of biogenic amine accumulation during the manufacture of five European traditional fermented sausages were studied concerning sausage formulation, the increase of sugar in the Italian salame abruzzese reduced the accumulation of cadaverine up to 43%. However, the addition of sugar in the French saucisson did not show a significant amine reduction. The inoculation of a decarboxylase-negative autochthonous starter culture reduced the biogenic amine accumulation in a different manner depending on the species and strain(s). The highest reduction was achieved by Lactobacillus sakei used in the Greek aeros thasou, resulting in a total putrescine reduction and a significant decrease in tyramine (62%) and histamine (71%). In Portuguese chouriços cadaverine reduction was only of 45% when a single strain of Staphylococcus equorum was inoculated, whereas a single strain of L. sakei or a mixture of S. equorum yielded a 75% and 89% of reduction, respectively. In Spanish fuet, a combination of L. sakei CTC6626 plus S. xylosus CTC6013 had only a very slight effect on tyramine reduction (19%) in Spanish fuet, whereas L. sakei CTC494 plus S. xylosus CTC6013 was capable to reduce tyraminogenesis by nearly 50%, suggesting that L. sakei CTC494 was the strain responsible for the additional tyramine reduction.     

Changes in biogenic amine levels during storage of Mexican-style soft and Spanish-style dry-ripened sausages with different aw values under modified atmosphere

Two raw sausages were prepared: a soft and a dry-ripened one, both by local traditional and industrial manufacturing practices. Sausages were packaged under a CO₂/N₂ atmosphere at different targeted activity water (a_w) values: 0.96 and 0.92 (soft sausages) and 0.88 and 0.82 (dry-ripened sausages). Sausages were then stored at 5 °C for 42 days or at 12 °C for 240 days (soft and a dry-ripened sausages, respectively). The time-related changes in dominant microbiota, pH and biogenic amine contents during storage were determined. Tyramine was the most abundant biogenic amine in all the sausages. Biogenic amine levels were higher in dry-ripened sausages than in soft sausages at packaging. However, during refrigerated storage soft sausages were fermented and the levels of biogenic amines increased (P < 0.05). At the end of storage, traditional soft sausages with 0.96 a_w presented comparable levels of biogenic amines to traditional dry-ripened sausages.     

Reduction of biogenic amine formation using a negative amino acid-decarboxylase starter culture for fermentation of Fuet sausages

The ability of Lactobacillus sakei CTC494, a negative amino acid-decarboxylase starter culture, to reduce biogenic amine accumulation during sausage fermentation and storage at 4 and 19 degrees C was studied. The effect on the amine formation of the tyramine producer Lactobacillus curvatus CTC371, as a positive strain, was also examined in comparison to a spontaneous fermentation process without starter culture (control batch). The polyamines spermine, spermidine, and diaminopropane were not influenced by the ripening, and their levels slightly decreased in all the batches throughout the storage. Tyramine, cadaverine, and putrescine were the main amines formed during the ripening. The addition of starter culture resulted in a decrease on the biogenic amine formation, depending on the strain inoculated. A great reduction in tyramine content was achieved when L. sakei CTC494 was inoculated, whereas L. curvatus CTC371 only attenuated tyramine accumulation compared with the control batch. Both starters were able to significantly limit the production of putrescine and cadaverine, and they inhibited tryptamine and phenylethylamine formation by the wild microbial flora. Tyramine levels of the control sausages rose during the storage at both temperatures, whereas those of cadaverine only increased at 19 degrees C. On the contrary, sausages manufactured through the starter controlled fermentation did not show changes of amine contents during the storage. The addition of a proper selected starter culture is advisable to produce safer sausages with low contents of biogenic amines.     

Influence of hygienic quality of raw materials on biogenic amine production during ripening and storage of dry fermented sausages

The effect of the hygienic status of raw materials on biogenic amine production during ripening and storage (at 4 and 15 degrees C) of fermented sausages was studied. Two portions of fresh lean and back fat pork were stored for 5 days at -20 degrees C (treatment A) and at 4 degrees C (treatment B), respectively. Raw materials of treatment A maintained their hygienic quality high and low amine content. Raw materials of treatment B showed from 1 to 3 log (CFU/g) higher microbial counts and a biogenic amine index near 50 mg/kg, indicating poorer hygienic quality. The quality of raw materials influenced the composition and the concentration of biogenic amines produced during the ripening sausages. Sausages of treatment A (A-sausages) showed a large accumulation of tyramine (up to 100 mg/kg dm) followed by putrescine and cadaverine (<15 mg/kg). In contrast, B-sausages resulted in earlier and much greater amine production, and cadaverine, tyramine, and putrescine levels were 50-, 2.6-, and 6.5-fold higher than those of A-sausages. Other biogenic amines, such as octopamine, tryptamine, phenylethylamine, and histamine were also produced in B-sausages. The higher proteolysis and the lower pH of B-sausages might have favored the decarboxylase activity of microorganisms. Biogenic amine contents of sausages during storage depended on the raw materials used and storage temperature. No significant modification on the amine contents was observed during the storage of A-sausages at either temperature. Greater changes occurred in B-sausages stored at 15 degrees C than in those stored at 4 degrees C. Higher temperatures favored proteolytic and decarboxylase reactions, resulting in increased amine concentrations after storage.     

The effect of different starter cultures and ripening temperatures on formation of biogenic amine in Turkish fermented sausages

Different starter culture added groups (Group I: Lactobacillus sake, Staphylococcus xylosus; Group II: Lactobacillus plantarum, Staphylococcus carnosus; Group III: Lactobacillus curvatus, Staphylococcus carnosus, and Staphylococcus xylosus) and control group sausage samples were produced experimentally at two different temperatures (22 and 26 °C). In raw materials and all groups, by the 0th, 2nd, 5th and 7th days of the ripening period, the analysis of HPLC and biogenic amine (tyramine, histamine, cadaverine, putrescine, phenylethylamine, tryptamine, spermine, and spermidine) amounts, microbiological (Lactic acid bacteria, Micrococcus/Staphylococcus, Enterobacteriaceae, Enterococcus spp., and moulds–yeasts) and chemical (pH, dry matter, and salt) have been done. During the ripening period, there is no statistical discrepancy (P > 0.05) in terms of biogenic amine amounts, microbiological, and chemical values detected from the sausage samples produced at 26 and 22 °C. However, in both levels of temperature, there is statistical discrepancy (P < 0.001) detected in terms of tyramine, putrescine values and the count of Enterococcus spp. between the starter culture added samples and control group samples. By this study, it has been stated that the ripening temperature does not make any statistical discrepancy (P > 0.05) for all values but the use of starter culture prevents the formation of biogenic amine in Turkish fermented sausages.     

FORMATIONS OF BIOGENIC AMINES IN TURKISH STYLE SAUSAGE DURING RIPENING AND STORAGE PERIODS

Changes of biogenic amine (histamine, β‐phenylethylamine, serotonin, spermine, spermidine, cadaverine, putresine, 1,7‐diamino heptane, tryptamine and tyramine) concentrations and pH values of Turkish style sausages were investigated during ripening and storage. Cadaverine and β‐phenylethylamine were not detected during the ripening and storage periods for all sausage types. Storage time had a significant (P<0.05) effect on the formation of all biogenic amines. Starter culture usage decreased (P<0.05) biogenic amine formation. Histamine levels were higher in sausages prepared without additives and lower in the sausages made with starter culture than the sausages made without starter culture. There was no effect of starter culture and additives on formation of tryptamine, 1,7‐diamino heptane, serotonin or spermidine. Starter culture and additives affected (P<0.05) the formation histamine, putrescine and spermine. pH values of sausages sharply decreased (P< 0.05) from 5.98 to about 4.53 during 3 days of ripening. After that, pH values increased slowly and were nearly constant during the storage period.     

Effects of refrigerated storage and processing technologies on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries

The effects of refrigerated storage at 2 °C and 95% RH and processing treatments on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries were investigated. During refrigerated storage, total phenolics (TPC), total monomeric anthocyanins (ACY), and radical scavenging activity (RSA) fluctuated in ‘Marion’, but TPC and ACY continuously declined in ‘Evergreen’. Oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) decreased by 20% and increased by 19% in ‘Evergreen’, respectively after 7-d refrigerated storage, while no changes (P > 0.05) in ‘Marion’ were observed. Compared with frozen samples, freeze-dried ‘Evergreen’ had higher TPC (21%), ACY (5.5%), and RSA (14%), while hot-air dried “Marion” had lower ACY (56%), ORAC (37%), and FRAP (27%) and hot-air dried ‘Evergreen’ had lower TPC (37%), ACY (84%), and RSA (13%). ORAC and FRAP in canned ‘Marion’ was 21-61% lower than that of frozen samples. Jam also had lower TPC and ACY (67-84%), RSA (˜80%), and ORAC and FRAP (65-77%) values than frozen ones in both varieties (P < 0.05). The 6-mo post-process room storage had little effect on the bioactive compounds of frozen and freeze dried samples, but reduced ACY in hot-air dried, canned, and jam samples, and antioxidant capacities of all samples (P < 0.05).     

Effect of fermentation temperature on the microbial and physicochemical properties of silver carp sausages inoculated with Pediococcus pentosaceus

The effect of fermentation with Pediococcus pentosaceus at different temperatures ranging from 15 to 37 °C on the quality characteristics of silver carp sausages was investigated. Higher temperature stimulated the rapid growth of lactic acid bacteria, resulting in a rapid decline in pH, and consequently suppressed the growth of Pseudomonas, Micrococcaceae and Enterobacteriaceae. However, increasing fermentation temperature gave a progressive increase in total volatile basic nitrogen and biogenic amines in fermented silver carp sausages. Histamine was the main biogenic amine, exceeding 100 mg/kg after 48 h of fermentation at temperatures above 30 °C. Higher content of non-protein nitrogen and α-amino nitrogen correlated with the electrophoretic studies, which showed that proteolysis of high molecular weight myofibrillar and sarcoplasmic proteins was more prominent at higher fermentation temperatures. Products fermented at 23–30 °C showed greatest consumer preference and most favourable textural properties.     

Factors affecting growth of foodborne pathogens on minimally processed apples

Escherichia coli O157:H7, Salmonella and Listeria innocua increased by more than 2 log₁₀ units over a 24 h period on fresh-cut ‘Golden Delicious’ apple plugs stored at 25 and 20 °C. L. innocua reached the same final population level at 10 °C meanwhile E. coli and Salmonella only increased 1.3 log₁₀ units after 6 days. Only L. innocua was able to grow at 5 °C. No significant differences were observed between the growth of foodborne pathogens on fresh-cut ‘Golden Delicious’, ‘Granny Smith’ and ‘Shampion’ apples stored at 25 and 5 °C. The treatment of ‘Golden Delicious’ and ‘Granny Smith’ apple plugs with the antioxidants, ascorbic acid (2%) and NatureSeal^® (6%), did not affect pathogen growth. The effect of passive modified atmosphere packaging (MAP) on the growth of E. coli, Salmonella and L. innocua on ‘Golden Delicious’ apple slices was also tested. There were no significant differences in growth of pathogens in MAP conditions compared with air packaging of ‘Golden Delicious’ apple plugs, but the growth of mesophilic and psychrotrophic microorganisms was inhibited. These results highlight the importance of avoiding contamination of fresh-cut fruit with foodborne pathogens and the maintenance of the cold chain during storage until consumption.     

The effect of ripening and storage conditions on the distribution of tyramine,putrescine and cadaverine in Edam-cheese

The aim of the work was to describe the development of selected biogenic amines (histamine, tyramine, putrescine and cadaverine) in 4 layers of Dutch-type cheese (Edam-cheese) depending on 3 ripening/storage regimes during a 98-day period. Biogenic amines were analysed by means of ion-exchange chromatography. A further goal was to identify microbial sources of biogenic amines in the material analysed. Phenotype characterization and repetitive sequence-based PCR fingerprinting were used to identify the isolated bacteria. The highest content of tyramine, putrescine and cadaverine was determined in cheeses stored in a ripening cellar at a temperature of 10 °C during the whole observation period. Lower biogenic amines content was determined in samples which were moved into a cold storage device (5 °C) after 38 days of storage in a ripening cellar (10 °C). The lowest concentrations of biogenic amines were detected in cheeses which were moved into a cold storage device (5 °C) after 23 days of storage in a ripening cellar (10 °C). During the 98-day period, histamine was not detected in any of the regimes. Within the cheeses analysed, non-starter lactic acid bacteria Lactobacillus curvatus, Lactobacillus casei/paracasei and Lactobacillus plantarum were detected as the main producers of the biogenic amines tested. In starter bacteria Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris the decarboxylase activity tested was not detected.     

发酵香肠中生物胺的研究

本文采用RP-HPLC法测定了发酵香肠中的生物胺(苯乙胺、腐胺、尸胺、组胺、酪胺、亚精胺、精胺)的含量。样品经0.4mol/L高氯酸溶液提取,丹磺酰氯衍生,流动相为乙腈和水,采用梯度洗脱,流速为1mL/min,紫外检测波长为254nm。该方法检测限为:腐胺、尸胺、亚精胺、酪胺和精胺为0.1μg/mL,组胺0.5μg/mL,苯乙胺0.05μg/mL。回收率分别为苯乙胺86.71%、腐胺88.88%、尸胺94.55%、组胺87.57%、酪胺83.67%、亚精胺88.55%、精胺94.91%。结果表明发酵香肠中生物胺的种类及含量因香肠的品种而异,7种生物胺平均总量为13.40mg/100g,变异范围为7.83~19.13mg/100g。本法简便、快速、灵敏、可靠。     

Biogenic Amines in Dry Sausages as Affected by Starter Culture and Contaminant Amine-Positive Lactobacillus

The effect of an amine-negative starter culture, containing Pediococcus pentosaceus and Staphylococcus carnosus, on the growth and amine formation of an amine-positive contaminant lactic acid bacterium (G 106) was studied in dry sausages. Levels of biogenic amines, precursor amino acids, pH, water activity and microbial counts were measured. Levels of phenylethylamine and tyramine increased in the sausages inoculated with the amine-positive strain. The starter culture did not prevent growth of G 106 or its amine formation capability. However, levels of histamine remained low although G 106 could produce histamine in vitro.     

Reduced biogenic amine contents in sauerkraut via addition of selected lactic acid bacteria

The contents of free amino acids and biogenic amines in spontaneously fermented sauerkraut, inoculated or not with specific lactic acid bacterium strains, were monitored throughout 45 d of storage. The strains tested were Lactobacillus plantarum 2142, Lactobacillus casei subsp. casei 2763 and Lactobacillus curvatus 2771. In both the control and the experiments, the total amino acid contents increased with time – and the predominant ones were aspartic acid, arginine and glutamic acid. However, upon inoculation with either strain, the total biogenic amine contents remained considerably lower than those of the control (especially in the cases of L. casei subsp. casei and L. curvatus); every single biogenic amine was actually below the 100 ppm-threshold. The dominant biogenic amines in the control were putrescine – and tyramine and histamine, to a lesser extent; the putrescine content was 10-fold lower if inoculation had taken place with either lactobacillus tested; and histamine and tyramine were essentially absent during storage, whereas they ranked above 200 ppm in the control by 45 d. Hence, an efficient food-grade biological tool was made available that constrains buildup of dangerous biogenic amines in fermented vegetables during storage.     

Assessment of safe enterococci as bioprotective cultures in low-acid fermented sausages combined with high hydrostatic pressure

Three bacteriocinogenic, non-aminogenic and non-virulent Enterococcus strains (Enterococcus faecium CTC8005, Enterococcus devriesei CTC8006 and Enterococcus casseliflavus CTC8003) were used as starter cultures in low-acid fermented sausages to assess their competitiveness and their bioprotective potential against Listeria monocytogenes and Staphylococcus aureus. The inoculated strains were successfully monitored by RAPD-PCR. All the strains were able to grow, survive and dominate the endogenous enterococci population and avoided the growth of Enterobacteriaceae. E. devriesei CTC8006 and E. faecium CTC8005 particularly inhibited the growth of L. monocytogenes during the whole ripening process. S. aureus was not affected by the inoculated bacteriocinogenic enterococci strains.     

Effect of selected autochthonous starter cultures on processing and quality characteristics of Greek fermented sausages

Selected autochthonous starter (SAS) cultures (i.e. Lactobacillus sakei 8416, Lactobacillus sakei 4413, and L. sakei 8426, L. plantarum 7423 and L. curvatus 8427) were used as starter cultures in addition to a control treatment in the production of fermented sausages. The SAS cultures had a rapid growth and dominated the fortuitous population of LAB during the whole fermentation and ripening process improving the sensory attributes in comparison to control. Apart from the treatment produced with L. sakei 8416, all other SAS cultures prevented the lipid oxidation to values lower than 1 mg malonaldehyde/kg. The Micrococcaceae count and the redness of the sausages was not affected by the smoking and the acidification during the fermentation in the treatments produced with L. sakei 8416 and L. sakei 4413. The treatment of L. sakei 4413 had the lowest (*P < 0.05) content of all biogenic amines. In comparison to the control, the reduction of tyramine was 13%, tryptamine 55%, cadaverine 60% and putrescine 72%. Sausages produced with SAS cultures L. sakei 4413 and L. sakei 8416 had the highest scores for all sensory attributes. The results indicated that the SAS culture of L. sakei 4413 is the best autochthonous starter culture for fermented sausages.     

Content of Vasoactive Amines in Sremski Kulen and Sremska Kobasica Traditional Dry Fermented Sausages From Vojvodina

The aim of this paper was to determine the content of vasoactive biogenic amines in Sremski kulen and Sremska kobasica and to estimate hygienic conditions and good manufacturing practice (GMP) according to proposed criteria. Formation of dansyl chloride derivatizated vasoactive amines were determined using HPLC–DAD. Tryptamine (47.6; 34.2 mg/kg), histamine (16.1; 6.42 mg/kg) and tyramine (95.1; 45.2 mg/kg) were detected in both investigated type of traditional dry fermented sausages while phenylethylamine was not detected. Total content of vasoactive amines did not exceed the sum (200 mg/kg) proposed as a possible indicator of hygienic conditions and GMP in sausage production.     

Technological and safety characteristics of Staphylococcaceae isolated from Spanish traditional dry-cured sausages

The aim of this study was to determine the technological properties (nitrate reductase, proteolytic and lipolytic activities; and the ability to grow at the temperature and pH values of fermenting sausage, and at high NaCl concentrations) and safety characteristics (amino acid decarboxylase and enterotoxigenic activities) of 38 strains of Staphylococcaceae (11 of Staphylococcus epidermidis, 15 of Staphylococcus equorum, 5 of Staphylococcus pasteuri and 7 of Staphylococcus saprophyticus) isolated from Androlla and Botillo, two Spanish traditional sausages, in order to evaluate their suitability as potential starter cultures in the manufacture of these sausages. Most strains were able to grow at 10 °C, in the presence of 10% and 15% NaCl and at pH values of 5.5 and 5.0, except for S. equorum strains, growth of which was reduced at these pH values. The proteolytic activity assessed by the agar plate method showed that 89.5% and 52.6% of the strains were able to hydrolyze sarcoplasmic and myofibrillar proteins, respectively. These results were not confirmed by electrophoretic assays as only 47.2% of the strains changed the SDS-PAGE profile of actin, myosin and/or sarcoplasmic protein extracts. The assessment of the lipolytic activity by titration showed that only 21.0% of the strains can hydrolyze pork fat to any extent; whereas the profiles of the freed fatty acids were different in the different strains. Most of the strains showed decarboxylase activity against histidine, lysine, ornithine and tyrosine, but the quantities of biogenic amines produced were in most cases <25 ppm and <5 ppm for putrescine and cadaverine, respectively. Only four strains (10.5%), of S. epidermidis, produced enterotoxin C.     

大蒜精油和发酵剂对熏马肠中生物胺及微生物分布的影响

为研究大蒜精油和发酵剂对熏马肠中生物胺的影响,采用高效液相色谱法测定熏马肠中生物胺含量,利用 宏基因组学技术分析熏马肠中微生物多样性和生物胺含量的变化情况。结果表明：将大蒜精油和发酵剂联合使用能 够很好地减少熏马肠中尸胺、腐胺、组胺、酪胺和苯乙胺的产生,对控制生物胺在熏马肠中的含量起到非常显著的 作用;熏马肠中含有丰富的微生物物种,通过样品科分类水平物种分析,得出乳酸菌在熏马肠整个加工过程都是优 势菌种,而葡萄球菌在成熟后期数量较多。     

Analysis of biogenic amines in northern and southern European sausages and role of flora in amine production

The biogenic amine contents, microbial counts and flora producing amines were investigated in four types of fermented sausages. Southern type European sausages (Italian and Belgian) showed higher tyramine and phenylethylamine values than northern type ones (Norwegian and Belgian). The spontaneous non-starter lactic acid bacteria could be responsible for the production of these amines in the Italian products, and the cocci Gram positive in the Belgian South ones. The Norwegian sausages showed the lowest total amine content of those studied. The two Belgian types were characterised by the highest putrescine contents, associated with high counts of Enterococcus. The production of amines in vitro by the starter cultures used in the manufacture of the sausages revealed that none of the Lactobacillus species produced any amines and only Kocuria varians and Staphylococcus carnosus showed phenylethylamine and tryptamine production. High correlations were found between the content of putrescine, histamine and cadaverine.