Applicazione di protocolli semplificati di Image Analysis nella caratterizzazione di salumi tipici della Campania

Un protocollo d’Analisi dell’Immagine è stata messo a punto per la determinazione di misure specifiche e globali dei lardelli di due tipologie di salami tipici campani. Sono stati considerati otto produttori rappresentativi dell’eterogeneità della totalità dei produttori campani. L’elaborazione delle immagini è stata effettuata direttamente sull’immagine acquisita. Come output del software sono stati considerati: l’area di ciascun lardello, l’area della fetta, l’indice di rotondità di ogni lardello di grasso, il numero di lardelli. Da questi sono stati estratti ed elaborati gli indici più idonei per la caratterizzazione dei salami in termini di determinazione della dimensione e della distribuzione dei lardelli di grasso. La tecnica è risultata molto efficace, veloce e riproducibile. L’indagine ha evidenziato la possibilità di definire parametri oggettivi inerenti l’apparenza (qualità visiva) dei salami, un problema affatto irrilevante per il perfezionamento dei disciplinari di produzione e per la difesa della tipicità

Predicting texture attributes from microstructural, rheological and thermal properties of hazelnut spreads

Eight trained assessors evaluated one visual, eight texture and four gustative attributes of 15 commercial spreads. In addition, 100 consumers evaluated the acceptability of the spreads. Rheological behavior of the samples was evaluated in transient (stress–relaxation test) and dynamic (strain and frequency sweep test) shear mode. Thermal measurements were also performed. Finally, the microstructure of the samples was analyzed by scanning electron microscopy. Partial least squares regression was used to predict acceptability from sensory attributes and texture from instrumental data. Scanning electron micrographs indicated that spreads differed in morphology, size and distribution of hazelnut particles. Overall liking of the spreads was found to be related to hazelnut flavor and texture attributes. Prediction of the most important texture properties from instrumental measurements was quite successful, especially for spreadability which was found negatively related to the consistency and flow indices and, secondly, for meltability which was found to be strongly dependent on measured thermal parameters

The influence of dietary fibres on bubble development during bread making

Dietary fibre is a common and important ingredient of a new generation of healthy food products which is experiencing rapidly increasing consumer demand. Dietary fibre increases the nutritional value of bread but usually at the same time affects rheological properties of dough and, in turn, the sensory properties of the resulting bread. The effect of fibres on bread baking performance has not been fully explored. Our investigation concerned the potential use of soluble and insoluble dietary fibres in wheat bread technology. The influence on dough rheological behavior, leavening and baking performance was studied. Doughs prepared from wheat flour containing various amounts of fibres were submitted to a lubricated squeezing test and to small amplitude oscillatory measurements. Bubble evolution during leavening and baking phases was studied by measuring the variation in time of the total volume of the sample by means of image analysis. Experimental evidence of the different behaviour of the doughs and bread, with fibres added, are presented and discussed. In general, the addition of insoluble fibres causes the dough’s strength to increase, mainly at high fibre content. By contrast, the presence of soluble fibres reduces the resistance of dough to large deformation. A negative effect of fibres on leavening is observed. The highest volume increase of the baked bread corresponds to the dough with the lowest content of fibres. The experimental evidence suggests some interesting conclusions: a) results from rheological measurements agree with those of macrostructure analysis and b) the functional role of fibres in bubble evolution depend on both the fibre source and fibre contents