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Abstract: A quality index method and a sensory scheme were developed to assess raw and cooked Mediterranean anchovies (Engraulis encrasicholus), respectively. Fresh anchovies were stored in ice for 7 days in three trials. The changes in sensory punctuations showed satisfactory correlations with time of storage. Enterobacteria were the first microorganisms that exceeded the maximum allowable limit for marketable fish according to the Spanish regulations, reaching more than 103 colony former units/g after 5 days of storage. Receiver operating characteristic curves of the sensory scores of raw and cooked anchovy against Enterobacteria counts were used to corroborate the suitability of the schemes. Areas under the curves were satisfactory and the estimated rejection values ranged from 0.43 to 0.51 and from 6.6 to 7.1 for raw and cooked anchovies, respectively. [Copyright &y& Elsevier]

Abstract: 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 (2.5cm diameter sausage), and putrescine in llonganissa (4.5cm). 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. [Copyright &y& Elsevier]

Tyramine and histamine are the main dietary bioactive amines related to acute adverse health effects. Dry fermented sausages can easily accumulate high levels of these hazards and are frequently consumed in Spain. The present work aims to assess the exposure to tyramine and histamine from the consumption of dry fermented sausages by the Spanish population and to assess the risk to suffer acute health effects from this exposure. A probabilistic estimation of the exposure to these hazards was derived combining probability distributions of these amines in dry fermented sausages (n = 474) and their consumption by the Spanish population. The mean dietary exposure to tyramine and histamine was 6.2 and 1.39 mg/meal, respectively. The risk of suffering hypertensive crisis or histamine intoxication by healthy population due to tyramine or histamine intake, respectively, exclusively from dry fermented sausages, can be considered negligible. For individuals under treatment with MAOI drugs, the probability to surpass the safe threshold dose (6 mg/meal) was estimated as 34%. For patients with histamine intolerance, even the presence of this amine in food is not tolerable and it could be estimated that 7000 individuals per million could be at risk to suffer the related symptoms after consuming dry fermented sausages. [ABSTRACT FROM AUTHOR]

Biologically active amines were determined in commercial soybean products. The antioxidant polyamines were found in both non-fermented and fermented soybean products. Natto and tempeh showed the highest content of polyamines (75–124 and 11–24 mg/kg of spermidine and spermine, respectively). On the other hand, the bacterial-related biogenic amines, tyramine, histamine, tryptamine and β-phenylethylamine, were detected in practically all fermented products with a high variability. The highest contents were found in sufu, tamari and soybean paste. Extremely high tyramine and histamine contents, 1700 and 700 mg/kg, respectively, found in some sufu samples could be unhealthy. However, biogenic amines observed in the other soybean products should not be a risk for healthy consumers. However, individuals who take monoamine and diamine oxidase inhibitors drugs should be strongly recommended to avoid this kind of products in order to suffer no adverse health effects. These biogenic amines were not detected in non-fermented soybean products. [ABSTRACT FROM AUTHOR]

The application of ultra high pressure homogenisation (UHPH) treatments is useful to obtain fine and stable soymilk emulsions. Changes of isoflavones, protein digestibility and lysine availability during 4 months of storage at 20 ± 2 °C in soymilk treated by UHPH (300 MPa and 75 °C of inlet temperature) were studied in comparison to UHT-sterilised soymilk (142 °C, 6 s). Results indicated that although there was a significantly higher extractability of isoflavones in UHT (about 38%) than in UHPH-treated samples (about 15%), similar total contents were found at the end of storage. The interconversion of isoflavones into β-glucosides was faster in UHT than in UHPH-treated soymilk. Similar evolution of protein digestibility in both UHPH and UHT-treated soymilks was found, being slightly higher in the initial UHT (88.4%) than in UHPH-treated samples (83.3%). No great differences were observed in the % of blocked lysine among samples after treatments, neither in their evolution throughout storage. [ABSTRACT FROM AUTHOR]

Highlights: [•] Changes of isoflavones in ultra-high-pressure homogenised (UHPH) soymilks under refrigerated storage. [•] Aglycone formation was lower in UHPH than in heat-processed samples. [•] In-vitro protein digestibility was similar during storage in heat-pasteurised and UHPH soymilks. [•] Blocked lysine was higher during storage in heat-pasteurised than in UHPH soymilks. [Copyright &y& Elsevier]

Highlights: [•] The effect of UHPH on the bioactive compounds of soymilk was studied. [•] Phytosterol and isoflavone extractability increased with the UHPH treatments. [•] Tocopherols were affected by the effect of UHPH treatment. [•] Polyamines were stable with the combinations of pressure and temperature applied. [Copyright &y& Elsevier]

Abstract: Ultra high pressure liquid chromatography (UHPLC) has become a widely used technique in separation science as it can shorten analysis time while maintaining resolution and increasing sensitivity. Here we developed a UHPLC method with UV detection for the simultaneous determination of isoflavone aglycones (daidzein, glycitein and genistein), their corresponding glycoside forms (daidzin, glycitin and genistin), and acetyl and malonyl conjugate forms of glycosides (malonyldaidzin, malonylglycitin, malonylgenistin, acetyldaidzin, acetylglycitin, acetylgenistin) in soy milk. The method allowed reliable determinations of 12 isoflavones in less than 8min of chromatographic elution. It provided a satisfactory linearity ranging from 0.1 to 5mg/L, except for daidzin and genistin, for which it ranged from 0.1 to 10mg/L. In addition, it showed acceptable chromatographic sensitivity, with a detection limit lower than 0.05mg/L and a determination limit below 0.2mg/L. The precision, in terms of relative standard deviation, was lower than 5% and the accuracy, as mean recovery, was greater than 95%. Total isoflavone content in commercial soy milk samples (n =8) ranged from 1805.22 to 3195.59mg/kg dw. Genistin and Daidzin were the major isoflavones in all samples. The proportion of aglycones, ß-glucosides, and acetyl and malonyl glucosides differed among the samples. ß-Glucosides were identified as the predominant forms. [Copyright &y& Elsevier]

Abstract: Aminogenesis in traditional fermented sausages produced in Europe was studied during manufacturing process taking into account technological, physico-chemical and microbial factors. Tyramine was the major amine, followed by putrescine and cadaverine, although the occurrence of di-amines was much more variable. By principal component analysis, relationships between aminogenesis and the country of origin, physico-chemical parameters, processing conditions and microbial counts, were not found, probably due to the high dispersion observed in those variables. Therefore, biogenic amines occurred irrespectively of physico-chemical changes and technological conditions applied for sausage manufacture. By cluster analysis, five groups of fermented sausages were identified on the basis of their quantitative and qualitative profile of total biogenic amine content. Group A included products from very low to low total amine content (from not detected to 150mg/kg); group B, products with moderate levels (from 150 to 350mg/kg) tyramine being the major amine; group C, also with moderate amine contents but cadaverine being the major amine; and groups D and E, comprising products with high (from 350 to 550mg/kg) and very high (higher than 550mg/kg) amine content, respectively. Samples with moderate, high or very high levels of biogenic amines could be considered as products of less quality, and their consumption could be unhealthy for sensitive individuals or for those under classical monoamine oxidase inhibitor drug therapy. [Copyright &y& Elsevier]

Abstract: Naturally fermented sausages produced in nine traditional French processing units and their environmental surfaces were characterised by microbial and physico-chemical analyses. Salmonella and Staphylococcus aureus were not detected in the environment whereas Listeria monocytogenes was detected in four samples. Staphylococcus/Kocuria, lactic acid bacteria (LAB), Enterobacteriaceae, Pseudomonas, yeasts/moulds and enterococci contaminated the surfaces of two processing units, indicating insufficient cleaning and disinfection procedures. The final sausages did not present any health risk in seven of the processing units. In two of the processing units, the final sausages were contaminated with S. aureus and L. monocytogenes, respectively, at levels exceeding the maximum tolerable limit. Staphylococcus/Kocuria and LAB grew well in the products. Biogenic amines were found in the majority of the final products. Their occurrence was associated with high numbers of lactic acid bacteria and enterococci. The study outlined the processing and microbial diversities of French naturally fermented sausages. [Copyright &y& Elsevier]

Abstract: The application of high hydrostatic pressure (200MPa) to meat batter just before sausage fermentation and the inoculation of starter culture were studied to improve the safety and quality of traditional Spanish fermented sausages (fuet and chorizo). Higher amounts of biogenic amines were formed in chorizo than in fuet. Without interfering with the ripening performance in terms of acidification, drying and proteolysis, hydrostatic pressure prevented enterobacteria growth but did not affect Gram-positive bacteria significantly. Subsequently, a strong inhibition of diamine (putrescine and cadaverine) accumulation was observed, but that of tyramine was not affected. The inoculated decarboxylase-negative strains, selected from indigenous bacteria of traditional sausages, were resistant to the HHP treatment, being able to lead the fermentation process, prevent enterococci development and significantly reduce enterobacteria counts. In sausages manufactured with either non-pressurized or pressurized meat batter, starter culture was the most protective measure against the accumulation of tyramine and both diamines. [Copyright &y& Elsevier]