Fac-simile Scheda Linee di Ricerca - Federalimentare

Obiettivo della ricerca è la messa a punto di modelli di previsione della degradazione degli oli extravergini di oliva, basati sulla combinazione di indici di stabilità e/o di instabilità che permettano distabilire se un olio si degradi più o meno rapidamente di un altro che abbia una differentecombinazione di tali indici. La combinazione deve essere indipendente dall’origine degli oli,dall’annata e dalle modalità produttive o, per meglio dire, tutte le possibili differenze tra gli oli sidevono tradurre ed interpretare in una diversa combinazione degli indici di stabilità e/o diinstabilità.Parole chiave- Olio extra vergine di oliva- Composti fenolici- Attività enzimatica- Shelf-life- Modellazione predittivaDati pubblicati inerenti il tema di ricerca1. Cherubini C., Migliorini M., Mugelli M., Viti P., Berti A., Cini E., Zanoni B. (2008). Towardsa technological ripening index for olive oil fruits. J Sci Food Agric, 89, 671-682.The aim of this work was to study the evolution of sugar and oil contents in Frantoio cultivar olives during ripeningto propose a technological ripening index for olive oil fruits. Olive fruits were picked in nine differentfarms once a week from the beginning of September to the beginning of December during three crop seasons. Asa result of the biochemical phenomenon of oil formation in olive fruits, sugar concentration during ripening wasshown to follow a sigmoidal decrease, which recurred periodically in different microclimates over years. Thistrend resulted to be the cause of an opposite sigmoidal increase in the oil content. Experimental data for sugarand oil contents were also statistically related by significant linear relationships. It was also observed that reachingminimum environmental temperatures ≤ 10°C resulted in a definite minimum asymptotic value for sugars.Sugar concentration was proposed as an accurate, reproducible index for technological ripening of olive oil fruitsby the following prediction function: Proper ripening degree of olives corresponds to achievement of a minimum,constant value for sugar content and, consequently, a maximum, constant value for oil content, associatedwith reduced risks of fermentation activities of olive paste.2. Siliani S., Mattei A., Benevieri Innocenti L., Zanoni B. (2006). Bitter taste and phenolic compoundsin extra virgin olive oil: an empirical relationship. Jnl. Food Qual., 29, 431-441.Bitter taste of extra virgin olive oil is known to be affected by the phenolic composition. However, contributionof each individual phenol to this sensory note has not been clearly defined. The aim of this study was to verifywhether there was a relationship between bitter sensation and phenolic compound concentration, to determinewhich compounds were involved in bitter taste and to evaluate quantitatively this correlation. Results confirmedthat a positive correlation did exist between total phenolic amount and bitter intensity. Data processing showedthat this correlation was significantly dependent upon a relationship between oleuropein aglycon (3,4-DHPEA-EA) and bitter intensity. An empirical exponential model was set up and validated.3. Migliorini M., Mugelli M., Cherubini C., Viti P., Zanoni B. (2006). Influence of O 2 on thequality of virgin olive oil during malaxation. Jnl. Sci. Food Agric, 86, 2140-2146.The aim of this work was to investigate the effect of malaxation operating conditions on virgin olive oil quality.Legal, sensory, nutritional parameters of olive oil were evaluated by identifying the role played by enzymes. Acomparison was made between oil obtained from a traditional malaxation plant and oil obtained from amalaxation equipment (LOM) able to work at low oxygen level and temperature.Research results showed that, during malaxation, oxygen had an effect on both phenolic compounds and fattyacids, mainly favouring enzyme phenomena. Malaxation at a low oxygen level was found to be selective for theformation of both phenolic and C 6 compounds. Oil obtained from malaxation LOM equipment were shown to beSISTAL - SOCIETA’ ITALIANA DI SCIENZE E TECNOLOGIE ALIMENTARIDipartimento di Scienze e Tecnologie Agroalimentari, Università degli Studi della TusciaVia San Camillo de Lellis, 01100 ViterboTel.: 0761- 35 74 94/7 , Fax: 0761- 35 74 98, e-mail: mmoresi@unitus.it113