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Copyright of Arquivo Brasileiro de Medicina Veterinaria e Zootecnia is the property of Universidade Federal de Minas Gerais, Escola de Veterinaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pesquisa Veterinaria Brasileira is the property of Colegio Brasileiro de Patologia Animal - CBPA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Any bacterial strain to be used as starter culture should have suitable characteristics, including a lack of amino acid decarboxylase activity. In this study, the decarboxylase activity of 76 bacterial strains, including lactic acid bacteria and grampositive, catalase-positive cocci, was investigated. These strains were previously isolated from European traditional fermented sausages to develop autochthonous starter cultures. Of all the strains tested, 48% of the lactic acid bacteria strains and 13% of gram-positive, catalase-positive cocci decarboxylated one or more amino acids. Aminogenic potential was strain dependent, although some species had a higher proportion of aminogenic strains than did others. Thus, all Lactobacillus curvatus strains and 70% of Lactobacillus brevis strains had the capacity to produce tyramine and β-phenylethylamine. Some strains also produced other aromatic amines, such as tryptamine and the diamines putrescine and cadaverine. All the enterococcal strains tested were decarboxylase positive, producing high amounts of tyramine and considerable amounts of β-phenylethylamine. None of the staphylococcal strains had tyrosine-decarboxylase activity, but some produced other amines. From the aminogenic point of view, Lactobacillus plantarum, Lactobacillus sakei, and Staphylococcus xylosus strains would be the most suitable for use as autochthonous starter cultures for traditional fermented sausages. [ABSTRACT FROM AUTHOR]

A total of 364 bacterial isolates, obtained from spinach leaves, were assayed in a decarboxylase broth containing histidine, lysine, and omithine to check their ability to produce biogenic amines, and then quantified by high-performance liquid chromatography. Among these isolates, 240 formed cadaverine, 208 formed putrescine, and 196 formed histamine, in widely varying amounts. They frequently produced more than one biogenic amine. Klebsiella pneumoniae subsp, pneumoniae and Morganella morganii were the main histamine producers, with mean values of 1,600 and 2,440 mg/liter, respectively, followed by Pantoea spp. 3 (1,710 mg/liter) and Hafnia alvei (2,500 mg/liter). Enterobacter amnigenus and Enterobacter cloacae produced particularly high amounts of putrescine, with mean values of 2,340 and 2,890 mg/liter, respectively. The strongest cadaverine formation was shown by Serratia liquefaciens (3,300 mg/liter), Serratia marcescens (3,280 mg/liter), and Stenotrophomonas mahophilia (1,000 mg/liter). [ABSTRACT FROM AUTHOR]

Biogenic amine accumulation was studied during the ice storage of Mediterranean hake. Sensory analysis and counts of Shewanella, Pseudomonas, enterobacteria, psychrotrophic, and mesophilic bacteria provided complementary information on hake spoilage. Putrescine and cadaverine were the main amines accumulated, whereas histamine and tyramine were minor amines but had qualitative interest from the hygienic point of view. Although all biogenic amines were less abundant than in pelagic fish, they may also be used as indicators of freshness and/or spoilage in hake. Cadaverine was the amine best correlated with Shewanella, which was the specific spoilage organism. Therefore, cadaverine may be regarded as the specific spoilage biogenic amine for hake stored at chilling temperatures. However, the biogenic amine index, which considers cadaverine, putrescine, histamine, and tyramine, has several advantages as an indicator of hake quality. Taking into account sensory data, an acceptability limit of the biogenic amine index could be established in 15 to 20 µg/g. [ABSTRACT FROM AUTHOR]

Chemical and microbiological parameters were studied during the industrial production of salt-ripened anchovies (Engraulis encrasicholus). Gradual acidification and increases in the proteolysis index and in total volatile basic nitrogen were observed. At the end of the maturing process, the values reached pH 5.55 ± 0.03, 21.33 ± 5.82%, and 44.06 ± 12.47 mg/ 100 g, respectively. In the three studied anchovy batches, the biogenic amines tyramine, histamine, putrescine, cadaverine, and agmatine increased during ripening. The highest values were found in the batch where initial microbial load was highest (batch 1), especially for enterobacteria and enterococci. Tyramine was the most abundant amine, reaching values from nondetectable to 90 mg/kg, whereas histamine did not surpass 20 mg/kg. Among the microorganisms isolated, Enterobacter cloacae, Aerococcus viridans, Kocuria varians, and Staphylococcus chromogenes were able to decarboxylate amino acids and produce biogenic amines in vitro. Most (70.59%) of the microorganisms identified were able to produce histamine, 23.53% were able to produce the diamines putrescine and cadaverine, and only 11.76% were able to produce tyramine, although this substance was the major biogenic amine found in anchovy samples. [ABSTRACT FROM AUTHOR]

Paprika from the region of La Vera (Cáceres) is prepared using a particular process of mild, slow drying in traditional drying barns heated by oakwood fires. This makes it possible for the fruit to maintain its natural components at the same time as contributing certain organoleptic characteristics that are highly appreciated by consumers. We analyzed the changes in the aromatic fraction that occur over the course of this traditional drying technology, using dynamic head space as the isolation method and gas chromatography–mass spectrometry as the identification system. We identified 96 compounds, 55 of which presented significant differences (P < 0.05) between different days of the drying process. Some 40% of the aromatic potential of the end product corresponded to volatile compounds that appeared during the drying process, originating from the wood smoke or as the result of typical reactions of the dehydrated products. [ABSTRACT FROM AUTHOR]

Vitamins A, E, and those of the B complex were determined in 59 standard and 11 specialized infant milks from the Spanish market. Water-soluble vitamin levels were lower than those declared by manufacturers in 50% of the standard infant milk products. Vitamin A ranged from 58.8 µg/100mL to 170.9 µg/100mL and vitamin E from 0.8 mg/100mL to 3.3 mg/100ml. Most of the samples had a higher vitamin A content than that stated by the manufacturer, and 13% and 42% of them exceeded the Spanish legislation and the ESPGAN recommendation levels respectively. Vitamin E levels were between 2 and 10 times higher than the minimum established by these organizations and in general were over the declared level. [ABSTRACT FROM AUTHOR]

Two infant milks claimed to have the same final composition in liquid and powdered form respectively were stored for 12 mo at 20, 30, and 37 °C. Vitamin E, thiamin, riboflavin, pyridoxine, folic acid, and nicotinamide remained constant at the three temperatures. However, there were statistically significant losses of vitamin A (approximately 35%) in samples stored at 37 °C. No differences were observed in vitamin stability between the two infant milks studied. Final levels of vitamin A were always higher than the minimum set by Spanish legislation. Vitamin A overfortification (approximately 200%) was more than that needed to compensate for losses during storage. [ABSTRACT FROM AUTHOR]