Concentrations Of Cadaverine Research Articles

Modulation of the nutritional value of lupine wholemeal and protein isolates using submerged and solid‐state fermentation with Pediococcus pentosaceus strains

SummaryThe influence of different factors (submerged and/or solid‐state fermentation, pediococci strain, lupine variety and protein isolation process) on the protein digestibility, total phenolic compounds (TPC) content and radical scavenging activity of Lupinus luteus and angustifolius wholemeal and protein isolates was evaluated. As safety factor, biogenic amines (Bas) formation was analysed. The Pediococcus pentosaceus strains No. 8, No. 9 and No. 10 are suitable starters for lupine wholemeal fermentation and both applied processes (fermentation and protein isolation) increase protein digestibility (by 10%). Higher TPC content in fermented wholemeal can be obtained, compare to isolates. In SMF isolates by 58.3%, 68.2%, 95.6%, 76.6%, lower content of phenylethylamine, putrescine, cadaverine and histamine, respectively was found. The highest protein digestibility and the lowest BAs content using submerged fermentation with pediococcus No. 8 in lupine variety Vilnius protein isolates can be obtained and this technology for high‐quality lupine proteins preparation can be recommended.

Time-course responses of ileal and fecal microbiota and metabolite profiles to antibiotics in cannulated pigs.

We investigated the time-course effects of therapeutic antibiotics on intestinal microbial composition and metabolism in an ileal-cannulated pig model. Sixteen ileal-cannulated piglets (12 ± 0.5kg) were assigned to two groups (n = 8) and fed standard diets with or without antibiotics. At 4days before, and at days 2, 7, and 13 after antibiotic administration, ileal and fecal samples were collected for analysis of microbiota composition via 16S rRNA MiSeq sequencing and metabolites (short-chain fatty acids, biogenic amines, and indole). It was found that Lactobacillus and Bifidobacterium had decreased by an average 2.68-fold and 508-fold in ileum on days 2-13, and by an average 45.08-fold and 71.50-fold in feces on days 7-13 (P < 0.05). Escherichia/Shigella had increased by an average 265-fold in ileum on days 2-13, and by an average 36.70-fold in feces on days 7-13 (P < 0.05). Acetate concentration had decreased in ileum by an average 2.88-fold on days 2-13, and by 1.83-fold in feces on day 7 (P < 0.05). Cadaverine concentration had increased by an average 7.03-fold in ileum on days 2-13, and by an average 9.96-fold in feces on days 7-13 (P < 0.05), and fecal indole concentration had increased by an average 2.51-fold on days 7-13 (P < 0.05). Correlation analysis between significant microbes and metabolites indicated that the antibiotic-induced microbiota shift appeared to result in the changes of intestinal metabolism. In conclusion, antibiotic administration led to dynamic changes in microbial communities and metabolism in ileum and feces, with ileal microbiota being more prone to shift than fecal microbiota.

Qualitative and quantitative evaluation of biogenic amines in vitro production by bacteria isolated from ewes’ milk cheeses

Studying the production of biogenic amines (BA) by cheese microbiota is important, because high BA concentrations in food represent a health risk for consumers. Qualitative screening with differential media and HPLC quantification were used to investigate the production of 8 BA (2-phenylethylamine, cadaverine, histamine, putrescine, spermidine, spermine, tryptamine, and tyramine) by 72 isolates from curd and cheese samples manufactured with raw and pasteurised ewes’ milk. Enterobacteriaceae showed good putrescine and cadaverine production, both for number of positive isolates and for concentrations produced (average: 341 and 785 µg ml−1, respectively). Among Enterobacteriaceae data are provided on BA formation by Pantoea conspicua, previously not isolated from food samples. All enterococci formed tyramine, often in high amounts (average: 1608 µg ml−1), and many produced notable 2-phenylethylamine, putrescine, and cadaverine concentrations (average: 184, 121, and 146 µg ml−1, respectively). BA formation by lactobacilli was overall extremely limited, with the notable exception of high tyramine concentrations produced by 1 Lactobacillus paracasei (800 µg ml−1) and 2 Lactobacillus curvatus (> 1700 µg ml−1), all isolated from pasteurised milk samples. Thus, undesired and technologically useful microorganisms both play a role in BA accumulation in cheeses.

An in vitro evaluation of the effects of a Yucca schidigera extract and chestnut tannins on composition and metabolic profiles of canine and feline faecal microbiota

ABSTRACTThe in vitro effect of a Yucca schidigera extract (YSE) and tannins from chestnut wood on composition and metabolic activity of canine and feline faecal microbiota was evaluated. Four treatments were carried out: control diet, chestnut tannins (CT), YSE and CT + YSE. The YSE was added to canine and feline faecal cultures at 0.1 g/l, while CT were added at 0.3 g/l for a 24-h incubation. A total of 130 volatile compounds were detected by means of headspace-solid phase microextraction gas-chromatography/mass spectrometry analyses. Several changes in the metabolite profiles of fermentation fluids were found, including a decrease of alcohols (−19%) and esters (−42%) in feline and canine inoculum, respectively, which was due to the antibacterial properties of tannins. In canine inoculum, after 6 h, YSE + CT caused lower cadaverine concentrations (−37%), while ammonia (−4%) and quinolone (−27%) were reduced by addition of CT. After 24 h, the presence of CT resulted in a decrease of sulphur compounds, such as dimethyl sulphide (−69%) and dimethyl disulphide (−20%). In feline faecal cultures, after 6 h, CT lowered the amount of indole (−48%), whereas YSE tended to decrease trimethylamine levels (−16%). Both in canine and feline inoculum, addition of CT and, to a minor extent, YSE affected volatile fatty acids patterns. In canine faecal cultures, CT exerted a marginal inhibitory effect on Escherichia coli population (−0.45 log 10 numbers of DNA copies/ml), while enterococci were increased (+2.06 log 10 numbers of DNA copies/ml) by YSE. The results from the present study show that YSE and tannins from chestnut wood exert different effects on the composition and metabolism of canine and feline faecal microbiota. In particular, the supplementation of YSE and tannins to diets for dogs and cats may be beneficial due to the reduction of the presence of some potentially toxic volatile metabolites in the animals’ intestine.

Reduction of biogenic amines in sufu by ethanol addition during ripening stage

The aim of this study was to investigate the content of biogenic amines (BAs) in different types of sufu samples obtained from different producers, and the effect of ethanol in reducing BA levels during sufu ripening. The results showed that different manufacturing processes altered the distribution of BAs in commercial sufu. Putrescine, cadaverine, histamine, and tryptamine were the main and common BAs in red, white and grey sufu. The contents of putrescine, cadaverine, tryptamine, β-phenylethylamine and tyramine in the grey sufu of all producer brands were significantly (p<0.05) higher than those in the white and red sufu. The addition of ethanol to the dressing mixture had a significant influence in reducing the total content of BAs in laboratory-made sufu. The slight increase in polypeptide and amino nitrogen contents after the addition of ethanol indicated a reduction in the degradation of water soluble protein.

Biogenic Amine Formation in Reformulated Cooked Sausage Without Added Nitrite

The purpose of this study was to assess the formation of biogenic amines (BA) during chilled storage (60 days) in cooked sausages made without added nitrite. Various combinations of ingredients celery, sodium lactate, carmine, orange dietary fibre and vitamins C and E - were used as substitutes for nitrite. BA levels were low irrespective of formulation, the largest variations between products were found in the case of cadaverine. The lowest (P < 0.05) cadaverine content was registered in samples with 0.1% added vitamin C, which also registered the lowest levels of enterobacteria and residual nitrite. The process offers health and safety benefits for consumers, and this strategy could thus be a good alternative to reduce and/or eliminate added nitrite in sausages and maintain product quality and safety (including BA formation) without this posing any risk to healthy consumers.

Consumption effect of a synbiotic beverage made from soy and yacon extracts containing Bifidobacterium animalis ssp. lactis BB-12 on the intestinal polyamine concentrations in elderly individuals

This study aimed to investigate the effect of a synbiotic beverage made from soy and yacon (Smallanthus sonchifolius) extracts containing Bifidobacterium animalis ssp. lactis BB-12 on healthy elderly individuals' intestinal polyamine concentrations. A randomized, double-blinded, placebo-controlled trial has been conducted with twenty-nine volunteers (over 65years of age) who either had a daily intake of 150mL of synbiotic (synbiotic group — S) or placebo (placebo group — P) beverages. Both had the same nutrient composition, except that a probiotic culture was added to the synbiotic beverage. Total experiment time was 8weeks, which was divided into 3 consecutive phases: a prefeeding period (2weeks), followed by a feeding period (4weeks) and a postfeeding period (2weeks). Stool samples were collected at 3 time periods. Fecal concentrations of polyamines, putrescine (PUT), cadaverine (CAD) and spermidine (SPD) that were obtained during the synbiotic and placebo consumption period were significantly higher (p<0.05) than those found during the pre-consumption baseline level period. No significant differences in the number of bifidobacteria, clostridia, or enterobacteria were observed in any of the two groups at the three time periods. Similarly, no significant effect on the production of proinflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and anti-inflammatory interleukin-10 (IL-10) was induced by the synbiotic or placebo beverages consumption. The results herein indicate that both the synbiotic and the placebo beverage consumption have increased polyamines levels, which are often reduced in elderly individuals, without influencing inflammatory responses. In addition, both placebo and synbiotic beverages seems to contribute by maintaining increased polyamines levels.

Biogenic amines degradation by microorganisms isolated from cheese

The aim of this study was the isolation and characterization of microorganisms able to degrade biogenic amines and their identification. Individual microorganisms were obtained by isolation from commercially available foodstuffs and food produced in the technological laboratories of Faculty of Technology, Tomas Bata University in Zlín and subsequently identified by MALDI-TOF MS. The results of MALDI-TOF MS identification were verified by 16S rRNA sequenation. In this work was studied the ability of 5 bacterial strains positive to biogenic amines degradation isolated from dairy products to decrease biogenic amines content in vitro and quantified reduction in the concentration of biogenic amines tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine and tyramine. The level of degradation (decrease of biogenic amines) was determined on the base of the ability to grow in media with biogenic amines as the sole source carbon and nitrogen. The isolated strains with the ability of degradation of one or more biogenic amines were cultured in medium supplemented with relevant biogenic amines, the media derivatized with dansyl chloride and these amines separated by HPLC at a wavelength of 254 nm. From five tested strains identified as Bacillus subtilis, Bacillus pumilus, Enterobacter cloacae, Rhizobium radiobacter and Acinetobacter pitii, isolated from gouda type cheese, the greatest ability of degradation was observed in Bacillus subtilis, which was capable to degrade almost all amount of histamine, cadaverine and putrescine. Other four strains showed a lower rate of degradation than Bacillus subtilis, but the ability to degrade biogenic amines with these microorganisms was still significant.

Effect of Some Essential Oils on Biogenic Amines in Fishes at Kalyobia Governorate

A grand total of 21 samples of fresh fish fillets (Oreochromis niloticus) were collected randomly from different fish markets in Benha, Kalyobia governorate to determine the effect of some essential oilsclove oil(1%), thyme oil (1%) and lemon oil(1%) at4C for 2and 4 days on their contents of various biogenic amines histamine, putrescine, cadaverine and tyramine. The results indicated that histamine levels in the examined fish fillets were reduced by 5.5% - 14.75% by addition of clove oil (1%), 7.25 - 20.0% by addition of thyme oil (1%) and 15.8% - 29.3% by addition of lemon oil (1%) after 2 and 4 days, respectively. While, addition of clove oil (1%), thyme oil (1%) and lemon oil (1%) cause reduction toputrescine by 9.6 - 11.9%, 12.5 - 16.4% and 19.35% - 34.1% after 2 and 4 days, respectively. Concerning to cadaverine levels, the reduction occurred by 7.7 – 9.3%, 10.4 – 22.9% and 15.8% - 29.8% after 2 and 4 days, respectively. Finally, addition of clove oil (1%), thyme oil (1%) and lemon oil (1%) cause reduction totyramine by 5.2 – 10.6%, 16.5 - 16.3% and 22.4% - 25.1% after 2 and 4 days, respectively. The obtained results it allow concluding that the addition of essential oils lead to reduction of biogenic amines in fish fillets eliminating the hazard effect of biogenic amines on human

Interactive effects of protein and carbohydrates on production of microbial metabolites in the large intestine of growing pigs

ABSTRACTThe study aimed at determining the effect of protein type and indigestible carbohydrates on the concentration of microbial metabolites in the large intestine of pigs. The experiment involved 36 pigs (15 kg initial body weight) divided into six groups, fed cereal-based diets with highly digestible casein (CAS) or potato protein concentrate (PPC) of lower ileal digestibility. Each diet was supplemented with cellulose, raw potato starch or pectin. After 2 weeks of feeding, pigs were sacrificed and samples of caecal and ascending, transverse and descending colon digesta were collected for analyses of microbial metabolites. PPC increased the concentration of ammonia, p-cresol, indole, n-butyrate, isovalerate and most of the amines in comparison with CAS. Pectin reduced the production of p-cresol, indole, phenylethylamine and isovalerate in the large intestine compared with potato starch. Starch and pectin increased mainly the concentration of n-butyrate and n-valerate in the colon compared to cellulose. Interaction affected mainly amines. Feeding PPC diet with potato starch considerably increased putrescine, cadaverine, tyramine and total amines concentrations compared with PPC diets with pectin and cellulose, whereas feeding CAS diet with starch reduced their concentrations. There was also a significant effect of interaction between diet and intestinal segment on microbial metabolites. In conclusion, PPC intensifies proteolysis in the large intestine and also n-butyrate production. Raw starch and pectin similarly increase n-butyrate concentration but pectin inhibits proteolysis more efficiently than starch. The interactive effects of both factors indicate that pectin and cellulose may beneficially affect fermentative processes in case of greater protein flow to the large intestine.

Estimation of some biogenic amines on chicken meat products

Sixty random samples of raw thigh & breast, half cooked chicken shawerma & shiesh tawook, fully cooked chickenshawerma and fully cooked chicken shiesh tawook (10 of each) were collected from different markets in Gharbiagovernorates and analyzed for biogenic amines by HPLC. The obtained results indicated that the mean values ofhistamine, cadaverine and putrescine (mg/100g) were 10.88 ± 0.91, 12.65 ± 1.10 and 4.54 ± 0.32 for raw thigh, 4.54 ±0.32, 9.86 ± 0.87 and 9.86 ± 0.87 for raw breast 16.56 ± 1.24, 19.81 ± 1.52, and 11.41 ± 0.96 for half cooked shawerma,12.29 ± 0.97, 16.20 ± 1.08 and 9.98 ± 1.08 for half cooked shiesh tawook, 12.93 ± 1.03, 16.69 ± 1.33 and 8.01 ± 0.63 forfully cooked shawerma and 11.68 ± 0.97, 11.91 ± 0.97 and 7.47 ± 0.50 respectively for fully cooked shiesh tawook.According to the permissible limits recommended by EOS (2005) 10%, 30%, 20%, 20% and 20% of the examinedsamples of raw thigh, half cooked shawerma, half cooked shiesh tawook, fully cooked shawerma and fully cooked shieshtawook were unaccepted. All raw breast samples were accepted as a result of their histamine content. While, 20%, 40%,30%, 30% and 20% of the examined samples raw thigh, half cooked shawerma, half cooked shiesh tawook, fully cookedshawerma and fully cooked shiesh tawook were unaccepted. Moreover, raw breast samples were accepted as result oftheir cadaverine content respectively. Accurately 10% of half cooked shawerma were unaccepted while all examinedsamples were accepted as a result of putrescine content

Changes in quality of rainbow trout (Oncorhynchus mykiss) fillets preserved with salt and sugar at low concentrations and stored at 4°C

ABSTRACTThe effects of dry-curing with low concentrations of salt and sugar on the quality of rainbow trout (Oncorhynchus mykiss) fillets were studied over a 16-day storage period at 4°C. Physicochemical characteristics (total volatile base nitrogen (TVB-N), biogenic amines (BAs), ATP-related compounds and K value), microbial populations (total aerobic counts (TAC), H2S-producing bacteria, Pseudomonas, Aeromonas, and lactic acid bacteria) and sensory (SA) indicators were analyzed. Fish samples were subjected to the following treatments: untreated (control), dry-cured with 1.3% salt (T1), and dry-cured with 1.3% salt that also contained 0.9% sugar (T2). SA indicated that the sensory quality of the control, T1, and T2 was unacceptable after 8, 12, and 12 days of storage, respectively. Moreover, the cadaverine concentration of treated samples was significantly lower (P < 0.05) than the control after storing for 8 days. T1 and T2 were significantly higher (P < 0.05) than the control in inosine 5-monophosphate (IMP) content from the 2th to 10th day. Cadaverine, putrescine, hypoxanthine, and TAC were correlated significantly (P < 0.01) with SA, and these seemed to be reliable indicators of fish quality. The results indicated that curing treatments extended the shelf life of rainbow trout fillets, which could be exploited by processors.

Low Biofilm Lysine Content in Refractory Chronic Periodontitis.

Chronic periodontitis is controlled without antibiotics by scaling and root planing (SRP) to remove dental biofilm. It has been previously reported that the epithelial barrier to bacterial proinflammatory products is impaired when biofilm lysine falls below the minimal content of normal blood plasma. Aims were to examine whether being refractory and requiring antibiotics to supplement SRP were associated with low biofilm lysine contents. Sixteen patients with periodontitis and six periodontally healthy volunteers (HVs) (respective mean ages: 57 ± 6 and 36 ± 8 years) were examined. Patients with periodontitis received SRP and surgery, and HVs received prophylaxis. At quarterly maintenance or prophylaxis visits during the subsequent year, therapeutic response was good (GR, n = 9) or poor (PR, n = 7; including five cigarette smokers). Biofilm cadaverine, lysine, and other amino acid (AA) contents were determined by liquid chromatography. Cadaverine mole fraction of lysine plus cadaverine (CF) indicated biofilm lysine decarboxylase activity. Biofilm lysine was 0.19 ± 0.10 and 0.20 ± 0.09 μmol/mg in GRs and HVs, but 0.07 ± 0.03 μmol/mg in PRs (Kruskal-Wallis: P <0.01). All AAs were depleted in biofilm from smokers, but only lysine was depleted in biofilm from non-smokers. CF was inversely associated with clinical attachment level (CAL) at baseline before therapy in all patients (R2 = 0.28, P <0.01) and with CAL change after therapy in GR (R2 = 0.49, P <0.05). Lysine and cadaverine contents discriminated PRs from GRs and HVs (Wilks' λ = 0.499, P <0.012). Refractory responses requiring antibiotic therapy result from smoking and/or microbial infections that starve the biofilm and epithelial attachment of lysine. Biofilm CF is associated with periodontitis severity pretherapy and extent of therapeutic response post-therapy.

A single identified glomerulus in the zebrafish olfactory bulb carries the high-affinity response to death-associated odor cadaverine

The death-associated odor cadaverine, generated by bacteria-mediated decarboxylation of lysine, has been described as the principal activator of a particular olfactory receptor in zebrafish, TAAR13c. Low concentrations of cadaverine activated mainly TAAR13c-expressing olfactory sensory neurons, suggesting TAAR13c as an important element of the neuronal processing pathway linking cadaverine stimulation to a strongly aversive innate behavioral response. Here, we characterized the initial steps of this neuronal pathway. First we identified TAAR13c-expressing cells as ciliated neurons, equivalent to the situation for mammalian taar genes, which shows a high degree of conservation despite the large evolutionary distance between teleost fishes and mammals. Next we identified the target area of cadaverine-responsive OSNs in the olfactory bulb. We report that cadaverine dose-dependently activates a group of dorsolateral glomeruli, at the lowest concentration down to a single invariant glomerulus, situated at the medial border of the dorsolateral cluster. This is the first demonstration of a single stereotyped target glomerulus in the fish olfactory system for a non-pheromone odor. A mix of different amines activates many glomeruli within the same dorsolateral cluster, suggesting this area to function as a general amine response region.

Identification and characterization of L-lysine decarboxylase from Huperzia serrata and its role in the metabolic pathway of lycopodium alkaloid

Lysine decarboxylation is the first biosynthetic step of Huperzine A (HupA). Six cDNAs encoding lysine decarboxylases (LDCs) were cloned from Huperzia serrata by degenerate PCR and rapid amplification of cDNA ends (RACE). One HsLDC isoform was functionally characterized as lysine decarboxylase. The HsLDC exhibited greatest catalytic efficiency (kcat/Km, 2.11 s−1 mM−1) toward L-lysine in vitro among all reported plant-LDCs. Moreover, transient expression of the HsLDC in tobacco leaves specifically increased cadaverine content from zero to 0.75 mg per gram of dry mass. Additionally, a convenient and reliable method used to detect the two catalytic products was developed. With the novel method, the enzymatic products of HsLDC and HsCAO, namely cadaverine and 5-aminopentanal, respectively, were detected simultaneously both in assay with purified enzymes and in transgenic tobacco leaves. This work not only provides direct evidence of the first two-step in biosynthetic pathway of HupA in Huperzia serrata and paves the way for further elucidation of the pathway, but also enables engineering heterologous production of HupA.

The impact of lactic acid bacteria with antimicrobial properties on biodegradation of polycyclic aromatic hydrocarbons and biogenic amines in cold smoked pork sausages

The influence of surface treatment with lactic acid bacteria (LAB), previously cultivated in an alternative substrate, on the formation of polycyclic aromatic hydrocarbons (PAHs) and biogenic amines (BAs) in cold smoked pork meat sausages was investigated. Moreover, sausages treatment with LAB after the smoking on PAHs content changes was evaluated. Additionally, the inhibitory effects of LAB metabolites on food spoilage bacteria was determined using the agar well diffusion assay method. The metabolites of Pediococcus acidilactici KTU05-7, Pediococcus pentosaceus KTU05-9 and Lactobacillus sakei KTU05-6 strains showed good inhibitory properties against tested pathogenic and food spoilage bacteria. Moreover L. sakei produced bacteriocins inhibited the growth of Pseudomonas aeruginosa and Escherichia coli. Furthermore, the treatment of sausages surface with LAB before smoking decreased the content of cadaverine and spermidine, whereas the treatment of sausages surface with LAB after smoking decreased the content of putrescine (approx. 53% when L. sakei and P. acidilactici were applied) or totally eliminated (applying P. pentosaceus) from outer layers and centre of sausages. The application of LAB for sausages treatment before and after smoking significantly decreased both benzo[a]pyrene and chrysene decreasing (p < 0.05). The results also confirm that potatoes juice could be used as an alternative substrate for LAB cultivation, and the obtained fermented bioproducts could be applied for surface treatment of cold smoked pork sausages in case to reduce microbial contamination, and PAHs content in final product.

Distribution free methods to model the content of biogenic amines in Spanish wines

Biogenic amines are formed from precursor amino acids by various microorganisms present in wine, and this may happen at any step of production, ageing or storage. The presence of these compounds is important because high amounts of them can lead to health problems. Also, biogenic amines can be potentially applied as indicators of food spoilage and/or authenticity.Nevertheless, there are complex relationships among biogenic amines in Spanish wines and their distribution is far from a normal distribution. Even though, this structure must be taken into account to provide a frame of reference on the quality of wines and to contribute to the efforts of the entire productive chain to attain consumer safety.In this work, 684 samples of wines from different Spanish regions have been analyzed in order to determine the content of histamine, tyramine, phenylethylamine, cadaverine and putrescine during 2010, 2014 and 2015. The statistical distribution of histamine has been modelled by using the β-content tolerance intervals. Besides, copulas to obtain the joint multivariate confidence region between histamine and tyramine have been built for the first time in the oenological field. The β-content tolerance intervals for histamine content, in the case of the population of red wines in 2010, lead to decide that only 53.9% of the distribution would be below 10ppm (with a 95% confidence in this affirmation). This percentage rises from 53.9 to 74.6% in the year 2014 and to 90.2% in 2015. Besides, the conjoint distribution of histamine and tyramine is modeled by a Clayton copula with margins estimated by Gaussian kernel, which allows concluding that this distribution is similar for the three years.

Comparative studies of quality changes in white and dark muscles from common carp (Cyprinus carpio) during refrigerated (4 °C) storage

SummaryDifferences between white and dark muscles from common carp (Cyprinus carpio) in sensory assessment, total viable counts (TVC), total volatile basic nitrogen (TVB‐N), pH, electrical conductivity (EC), biogenic amines (BAs), nucleotide degradation products and colours were investigated under air and vacuum conditions during refrigerated (4 °C) storage. Compared with white muscle, dark muscle had a higher lipid content, but lower crude protein and moisture content. TVC, TVB‐N, pH, and L* value were higher in white muscle, while K value and a* value were higher in dark muscle. Under both conditions, white and dark muscles had significant (P &lt; 0.05) differences in tyramine and cadaverine content. Although dark muscle was significantly (P &lt; 0.05) lower in ATP content, it had higher rate of IMP degradation and K value increase. Taking sensory and microbial indexes into consideration, dark muscle appeared to have a longer shelf life than white muscle under both conditions.

Effects of storage temperatures, vacuum packaging, and high hydrostatic pressure treatment on the formation of biogenic amines in Gwamegi

This study investigated the effects of storage temperatures, vacuum packaging, and high hydrostatic pressure (HHP) on the formation of biogenic amines (BAs) in Gwamegi. The Gwamegi samples were subjected to 400 MPa pressure for 10 min at 20 °C or vacuum packaging, and then stored at −16, 5, or 25 °C for 28 days. The amounts of six BAs (histamine, tyramine, cadaverine, putrescine, spermine, and spermidine) and the total plate counts were checked weekly. Compared with the control at 5 °C, the total plate counts were 2–3 log CFU lower for the HHP-treated samples and 1–3 log lower for the vacuum-packaged samples. Tyramine, spermine, and spermidine were found in Gwamegi stored at −16 °C and tyramine, cadaverine, spermine, and spermidine at 5 °C, whereas all six BAs were found at 25 °C. Histamine was relatively low in amount in all the treated samples. The BAs reached a high level during storage at 25 °C, with the total concentration reaching 1099 ppm in 28 days. After HHP treatment or vacuum packaging, the concentration of cadaverine and spermidine decreased, whereas that of tyramine and spermine increased. Tyramine was the dominant BA in all the samples and during storage at 5 °C in the control (0–56.67 ppm), HHP-treated (0–105 ppm), and vacuum-packaged (0–90 ppm) samples. Both HHP treatment and vacuum packaging effectively reduced the formation of some types of BAs and improved the microbial quality in Gwamegi. However, simultaneously, they also promoted the formation of others types of BAs such as tyramine and spermine.

Biogenic amines and hygienic quality of lucerne silage

AbstractThis experiment examined the influence of two different silage additives of biological (Lactococcus lactis, Lactobacillus plantarum, Enterococcus faecium, enzyme xylanase) and chemical (43% formic acid, 30% ammonium formate, 10% propionic acid, 2% benzoic acid) types on biogenic amines concentration, nutrient content, fermentation process, and microbiologic indicators in lucerne (Medicago sativa) silage after 90 days of fermentation. The biological additive significantly (P &lt; 0.05) increased putrescine (+51%), lactic acid (+11%) and protein content (+11%) in comparison with control silage. It significantly decreased cadaverine (−29%), histamine (−57%), spermidine (−15%), spermine (−55%), acetic acid (−40%), ethanol (−55%), ammonium (−25%) and ash (−9%). After the chemical-additive treatment, greater amounts of histamine and tyramine were recorded. Significant decrease was observed in the concentrations of putrescine (−18%), cadaverine (−55%), spermidine (−47%), spermine (−45%), lactic acid (−16%), acetic acid (−46%), ammonium (−59%), ash (−13%) and fat (−24%). Populations of bacteria associated with lactic acid fermentation, moulds, yeasts, enterobacteria and total microorganisms count were also influenced. Both biological and chemical additives can be highly recommended for producing high-quality silages meeting hygienic requirements. In lucerne silage, the chemical preservative showed a stronger effect in achieving the health safety of silage compared to the biological inoculant.