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The oxidative and hydrolytic degradation of the lipid fraction of ripened sausages as influenced by the raw material
No full textAbstract: An experimental investigation was conducted to assess the actual degree of oxidative degradation
of the lipid fraction of 30-day-ripened sausages using both commonly used investigations and nonconventional
means, such as the high-performance size-exclusion chromatography analysis of polar
compounds. Sausages made from pork shoulders from extensive and intensive pig rearing were considered.
The obtained results showed a high degree of primary oxidative degradation of the sausage lipid fraction,
as evidenced by oxidized triacylglyrerol and peroxide values, while a low secondary oxidation of fats
was found, as evidenced by triacylglycerol oligopolymers and 2-tiobarbituric acid test values. Moreover,
the degree of oxidative degradation did not show any significant difference between the two types of
sausage, although the samples prepared from extensively reared pigs, as compared with those from
intensively reared pigs, showed significantly (p < 0.001) higher contents of polyunsaturated fatty acids and
significantly (p < 0.01) lower amounts of saturated fatty acids
Assessment of the oxidative and hydrolytic degradation of the lipid fraction of mortadella by means of HPSEC analyses of polar compounds
No full textThe aim of this work was to use the HPSEC analysis of polar compounds to assess the level of oxidative and hydrolytic degradation of the lipid fraction of mortadella. The results indicated high primary oxidative degradation of the lipid fraction in the samples, with a mean value for oxidized triacylglycerols of 1.77%, and low secondary oxidation, with a mean value for triacylglycerol oligopolymers of 0.16%. In addition, in some cases, significant hydrolytic degradation was found. HPSEC analysis of polar compounds, to evaluate the level of oxidative and hydrolytic degradation of the mortadella lipid fraction, could be used as an alternative to commonly used techniques, some of which are not always reliable
Influenza della qualità della materia prima sul contenuto in PUFA di salsicce stagionate
No full text
Variations of the sensory profile of durum wheat Altamura PDO (Protected Designation of Origin) bread during staling
No full textThe typical sensory characteristics of Altamura PDO (protected designation of origin) bread are due
to both the use of durum wheat remilled semolina and the prolonged sponge-dough method based on sourdough.
In this paper the sensory properties of Altamura bread were evaluated during a period of 6 days from baking. A
total number of 24 descriptors was considered. The obtained results indicated that during the whole storage period
manyof the desirable characters such as crust consistence, crumbelasticity, crumbcohesiveness, overall aroma, and
sour aroma decreased, while the undesirable stale aroma and crumb consistence increased their intensity. In any
case, after 4 days from the production crumb color, crumb grain, crumb elasticity, and crumb humidity did not vary
significantly
Bouillon cubes: assessment of the state of degradation of the lipid fraction
No full textAn experimental investigation was carried out to assess the oxidative and hydrolytic quality of the
lipid fraction of bouillon cubes. Besides the routine analyses prescribed by EC regulations, determinations
of fatty acid composition and unsaturated fatty acid trans isomers were also performed. From the lipid
fraction extracted from each cube, polar compounds were separated by silica gel column chromatography
and then submitted to HPSEC (high-performance size exclusion chromatography) analysis to determine
the classes of substances deriving fromoxidation, polymerisation and hydrolysis of triglycerides. The data
obtained showed that the determination of trans isomers and the subsequent HPSEC analysis of polar
compounds enable one to ascertain the actual degradation of the lipid fraction of such food preparations.
The degree of degradation of the lipid fraction of bouillon cubes was similar to that normally found in
olive-pomace oil, which is the poorest olive oil commercial class. Finally, the contents of trans isomers and
triglyceride oligopolymers are shown to be significantly higher in hydrogenated than in non-hydrogenated
vegetable fats
Le classi di sostanze di ossidazione, polimerizzazione ed idrolisi dell'olio di oliva. Loro impiego nell'accertamento di qualità
No full textInfluenza del processo tecnologico sulla qualità della frazione lipidica dei biscotti
No full textAn experimental investigation was carried
out to evaluate the influence of technological
process on the quality of biscuit lipid
fraction. For this purpose, the degradation
of the lipid fraction of biscuits and that of
fats in dough were compared. The fatty
acid composition, trans isomers, peroxide
value, spectrophotometric constants were
determined, as well as the High-Performance
Size-Exclusion Chromatography (HPSEC)
analysis of polar compounds of the lipid
fraction of the examined samples, extracted
by Folch method. The obtained results
showed that the processing of biscuits gave
place to a significant increase of oxidative
degradation (about 30%), while it did not
influence the trans isomers content
Effetti dell'aggiunta di tocoferoli naturali sull'evoluzione delle caratteristiche sensoriali di corn flakes nel corso della conservazione
No full textIn order to investigate on the appearance and evolution of sensory defects due to lipid oxidation during the storage of breakfast cereals, and on the possibility to slow down such phenomena, corn flakes added with natural tocopherols have been compared with a control without added antioxidants. The sensory evaluation and the statistic analysis of the data (ANOVA and PCA) have underlined that during the storage of the cereals sensory defects appeared, both nasal and retronasal, due to the lipid oxidation, defined as stale, rancid and pungent. The flakes without added tocopherols presented significantly more intense off-flavors than those perceived in the flakes with added antioxidants, which showed sensory profiles comparable to those shown by control in preceding storage phases
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