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bstract Batches of gutted Mediterranean hake ( Merluccius merluccius var. Mediterraneus) were stored, in different seasons of the year, for up to 20 d in ice. Changes in trimethylamine (TMA-N), total volatile bases (TVB-N), P-ratio and trimethylamine oxide (TMAO) were measured; sensory evaluation of raw and cooked hake samples was also carried out. Similar profiles were observed between the different trials for all the parameters studied. TVB-N was not correlated with the time of ice storage, and proved to be better as a spoilage index than a freshness one. In contrast, TMA-N appears to be a good index of hake quality, and the value of 5 mg/100g offish seems an appropriate limit of acceptability. P-ratio was a poorer index of freshness than was TMA-N. [ABSTRACT FROM AUTHOR]

Biogenic amines and polyamines were measured in unripened cheese and 4 types of ripened cheese. The study included cheeses produced from both pasteurized and raw milks. All amines were lower in unripened than in ripened cheeses. The amine contents varied among different types of ripened cheese, within the same type of cheese, and also within the parts of cheeses. The main amines in ripened cheeses were tyramine, cadaverine, and putrescine. The highest concentration of tyramine was found in hard-ripened raw-milk cheeses, while blue cheese had the highest level of cadaverine. Unripened cheeses could be considered as well-tolerated products for histamine- and tyramine-sensitive individuals, whereas the wide variability in biogenic amines makes it difficult to generalize this consideration for all ripened cheeses. [ABSTRACT FROM AUTHOR]

BSTRACT: The formation of biogenic amines in goat cheese can be prevented through ensuring hygiene in raw materials and during manufacture, thereby avoiding potential decarboxylating microorganisms. High-pressure treatment may be used to inactivate microorganisms and is a potential alternative to pasteurization. This treatment could provoke higher proteolysis than pasteurization, leading to a higher availability of biogenic amine precursors. We compared the biogenic amine profile throughout the ripening of goat cheese made from pressurized milk with that obtained from pasteurized milk. Results indicate that the profile of biogenic amines is very similar for both cheeses. Tyramine was the prevailing amine in both cheeses, followed by cadaverine, putrescine, and histamine. [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]