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During the baking process for taralli production, a typical baked product of the Apulian tradition, the choice of ingredients plays a crucial role both for the quality of the final product and for the shelf-life. Growing demand from manufacturers is to further extend the shelf life both to meet market needs and to reduce food waste. For this purpose, an olive leaf extract, rich in polyphenols, was added to the taralli, whose oxidative process was monitored. After six months of storage, the taralli with the olive leaf extract added showed a significant reduction in the amount of volatile oxidation compounds, whereas an increase in oxidative stability measured by RapidOxy and antioxidant activity were obtained. Even the sensory parameters considered in the panel test were improved in the taralli with the extract added.

Microgreens have been recently introduced as a new category of vegetables, with unexploited potential as functional foods. Due to containerized production, they can be commercialized while growing on the medium, ready for being harvested before use. The chlorophyll content of vegetables is important for both health benefits and visual appearance of the produce. This paper aims to evaluate the feasibility of using simple tools to monitor chlorophyll content in microgreens of two different species, broccoli raab (Brassica rapa L., Broccoletto group) and radish (Raphanus sativus L.), in varying stages of cold storage in their growing vessel. Image acquisition with a CCD camera, followed by image analysis using preset algorithms of an open source software (ImageJ) was the approach used. Image color analysis (median values of L∗, a∗, and b∗indices) and textural parameters obtained from the gray-level co-occurrence matrix (GLCM) allowed to obtain regression models for chlorophyll content with satisfactory fitting parameters (adjusted R2 was 0.765 and 0.843 for broccoli raab and radish, respectively). These results point out the possibility to set up low-cost, real time, non-destructive monitoring systems for microgreens quality during their growing as well as during storage.

BACKGROUND: Nowadays, olive oil extraction is basically achieved by means of two-phase decanters, which allow a reduction of water consumption and the leaching of phenolic compounds. Despite this, most of the working settings derive from studies carried out on three-phase decanters. Hence, the aim of the present study was to assess the influence of two-phase decanter feed pipe position (FP) on the extraction efficiency and chemical-sensory characteristics of virgin olive oil. Three different positions were considered: at 825 mm (FP1), 610 mm (FP2) and 520 mm (FP3) from the outlet of the oily phase. RESULTS: Position FP3 allowed the highest oil recovery (up to 10%), the lowest percentage of oil in the olive pomace and, in general, a regular trend in terms of oil extraction efficiency. However, the oily must that came out of the decanter was not completely clean in terms of residual content of solid sediment and water. The feeding position partially affected the profile of antioxidant compounds. CONCLUSION: In two-phase decanters, loading the olive paste close to the outlet of the oily phase is recommended to increase the extraction efficiency without jeopardizing the chemical-sensory characteristics of virgin olive oil. © 2018 Society of Chemical Industry.

BACKGROUND: Several workers have studied the effect of harvest time on chemical and nutritional composition of almonds, but the results are partly conflicting, probably due to differences in the cultivars considered and to different agronomic and climatic conditions in the growing areas. In this paper, the influence of harvest time and cultivar on the chemical and nutritional composition of almonds (Prunus dulcis (Mill). D.A. Webb) were evaluated. Ten cultivars were considered, grown in the same orchard and subjected to the same agronomical regime. Almonds were collected at two different harvest times: (i) when the fruits were unripe, but already edible, and showed green and moist hull; and (ii) when the fruits were ripe, with dry brown hull. The analyses of proximate composition, fatty acid profile, total phenolic compounds, and antioxidant activity were carried out. RESULTS: Lipid content increased (P < 0.001) during ripening, while both protein and carbohydrate content decreased (P < 0.01). Fatty acid composition showed a not univocal behavior during ripening and was highly influenced by cultivar. Total phenolic compounds and antioxidant activity varied among cultivars but increased during ripening with the exception of cv Marcona. The ‘Genco’ and ‘Francolì’ cultivars were found to be phenolic rich. CONCLUSION: Harvest time and cultivar significantly influenced the chemical and nutritional composition of almonds. Genotype strongly influenced fatty acid composition and total phenolic compounds. The changes of bioactive compounds and antioxidant activity suggest that the synthesis of antioxidants also occurs in the last stage of ripening. Unripe almonds, a valuable niche product, showed interesting nutritional value. © 2018 Society of Chemical Industry.

Leggendo l’indice di quest’opera, si rimane colpiti nel vedere in quanti modi la nutrizione entri, direttamente o indirettamente, nella nostra vita. È un universo che solo da poco tempo la scienza ha cominciato a esplorare, scoprendo molte cose (e sfatandone anche tante altre). È per questa ragione che da più di 20 anni abbiamo creato a SuperQuark la rubrica “Scienza in cucina” (affidata proprio a una co-autrice di questo volume). Si dice spesso che il cibo è il carburante del nostro corpo: in realtà non è solo così. Il cibo “è” il nostro corpo. Noi infatti siamo interamente costruiti con i materiali dei cibi che mangiamo. Le nostre cellule sono come gli individui: nascono, si nutrono, eliminano rifiuti, invecchiano e infine muoiono, mentre altre prendono il loro posto. È come se una casa venisse continuamente demolita, mattone per mattone, e ricostruita con altri nuovi. Questo vale anche per il cervello: è vero che le cellule nervose non si replicano (tranne in alcuni casi) ma ogni singola cellula nervosa ha (a livello molecolare) il suo metabolismo e anch’essa si rinnova con i materiali portati dall’alimentazione. In fondo, anche la stessa lotta per la sopravvivenza in natura, e quindi l’evoluzione, è profondamente legata alla competizione sul cibo. A tutto ciò non pensiamo quando ci mettiamo a tavola, ma all’interno del nostro organismo agisce senza sosta una efficientissima catena di smontaggio e di rimontaggio, che richiede un equilibrio fra i materiali che entrano e quelli che vengono eliminati, in modo che sia assicurato un corretto funzionamento d’insieme. Se la qualità, o la quantità, dei nutrienti è sbagliata, a lungo andare l’organismo ne subisce le conseguenze generando, per esempio, denutrizione, oppure obesità: ma tra questi due estremi esiste una grande varietà di situazioni che spesso possono ridurre l’efficienza del sistema o “ingolfare” la macchina, provocando vari tipi di patologie. Nel campo della nutrizione le ricerche avanzano a ritmo incredibile, e spesso certe conoscenze del passato vanno rivisitate con un’angolazione diversa: come l’interazione personalizzata di ogni organismo con il cibo in funzione del genoma, delle condizioni fisiologiche o patologiche, e anche alla luce delle recenti scoperte nel campo dell’epigenetica. Un altro settore in continua evoluzione è quello riguardante il ruolo del cosiddetto microbiota (cioè dei microrganismi presenti in enorme quantità nell’apparato digerente, e diversi in ogni individuo) nello sviluppo e nel funzionamento dell’intero organismo umano. Insomma, si sta scoprendo sempre più quanto ogni individuo abbia un rapporto particolare con il cibo, al punto di prevedere in futuro dei modelli di alimentazione personalizzati, in funzione delle caratteristiche fisiche, del tipo di attività, ma basandosi anche su elementi finora non presi in considerazione. Questo libro affronta proprio i diversi aspetti del rapporto tra alimentazione, nutrizione e salute, e si propone di aiutare chi studia e lavora in questo campo per meglio orientarsi tra la grande quantità di messaggi che provengono dal mondo della ricerca. Grazie a queste nuove conoscenze, inoltre, diventa anche possibile agire in modo più efficace su due grandi leve che regolano il corretto rapporto tra cibo e salute: la prevenzione e l’educazione alimentare. Piero Angela

The aim of this research was the chemical, microbiological, and sensory characterization of new ingredient formulations of olive-based pâtés, since few studies are present in the literature regarding table olive-based processed products. Three ingredient formulations were selected by a consumer test on the basis of the scores of odour and taste descriptors, higher than 6 (linear scale 0-10 cm). The chemical and sensory analyses allowed to clearly differentiate all ingredient formulations on the basis of both composition and volatile profile. Microbiological data corresponded to levels usually detected for similar products and excluded the presence of pathogens. Finally, no off-flavour was perceveid in the tested formulations.

BACKGROUND: Few studies have investigated the effects of frozen storage on processed vegetables. The present study evaluates its effects on the quality characteristics of non-thermally stabilized tomato-based pâtés compared to thermally stabilized pâtés stored at room temperature. Two different types of tomato-based pâtés were analyzed in terms of bio-active compounds, as well as colorimetric parameters and oxidative degradation just after processing and also after 4, 8 and 12 months of storage. RESULTS: Thermal treatment mainly affected the colorimetric parameters and oxidative degradation, whereas its effects on bio-active compounds became more visible and significant during storage. Freezing allowed in both pâtés to maintain significantly higher a* values than storage at room temperature, whereas brightness, which is linked to residual activities of different enzymes, varied during storage according to the ingredient formulation. During storage, oxidative degradation of the lipid fraction was more marked in the pâté containing a lower quality oil, and less marked when the absence of thermal treatment was combined with frozen storage. CONCLUSION: Freezing could represent a viable alternative way to preserve high-quality products over time. An optimal combination of blanching, freezing rate, storage and thawing conditions will provide the best results in terms of the quality/price ratio. © 2017 Society of Chemical Industry.

In recent years, an increasing number of typicality marks has been awarded to high-quality olive oils produced from local cultivars. In this case, quality control requires effective varietal checks of the starting materials. Moreover, accurate cultivar identification is essential in vegetative-propagated plants distributed by nurseries and is a pre-requisite to register new cultivars. Food genomics provides many tools for cultivar identification and traceability from tree to oil and table olives. The results of the application of different classes of DNA markers to olive with the purpose of checking cultivar identity and variability of plant material are extensively discussed in this review, with special regard to repeatability issues and polymorphism degree. The characterization of olive germplasm from all countries of the Mediterranean basin and from less studied geographical areas is described and innovative high-throughput molecular tools to manage reference collections are reviewed. Then the transferability of DNA markers to processed products – virgin olive oils and table olives – is overviewed to point out strengths and weaknesses, with special regard to (i) the influence of processing steps and storage time on the quantity and quality of residual DNA, (ii) recent advances to overcome the bottleneck of DNA extraction from processed products, (iii) factors affecting whole comparability of DNA profiles between fresh plant materials and end-products, (iv) drawbacks in the analysis of multi-cultivar versus single-cultivar end-products and (v) the potential of quantitative polymerase chain reaction (PCR)-based techniques.

BACKGROUND: Conflicting results about the effect of modified atmosphere packaging (MAP) rich in CO2 on the quality of different kinds of meat products are present in the literature. In this study, the degree of lipid degradation and the sensory characteristics of ripened sausages packed in modified atmosphere at three different carbon dioxide (CO2) concentrations were evaluated during 5 months of storage. RESULTS: The degree of hydrolytic degradation of the lipid fraction was found to decrease with increasing CO2 concentration. Similarly, oxidative phenomena occurred at a lower rate when the CO2 concentration increased. The variations in CO2 concentration influenced the perception of rancid flavor in the examined sausages. CONCLUSION: An increase in CO2 concentration in MAP slowed down the evolution of lipid oxidation owing to the minor extent of hydrolytic degradation, whose products have pro-oxidant activity. This effect was more evident in the first 2 months of storage. © 2015 Society of Chemical Industry

Various research was carried out in order to study the effect of the use of atmospheres richer in CO2 for packaging sausages, with results that were, in some cases, not univocal, as a consequence of intrinsic (pH, water activity, fat content, type of skin used) and extrinsic (CO2 concentration, headspace to meat volume ratio, storage temperature) factors that influence the rate of CO2 dissolution in meat. The aim of the present investigation was to assess the effect of three different levels of CO2 concentration on the evolution during storage of the sensorial characteristics and of the lipid fraction degradation phenomena in unsliced ripened sausages with skin (that is the type of commercial presentation more diffuse for this type of product). The obtained results highlight the influence of the CO2 level used in the packaging atmospheres on the sensorial characteristics and on the evolution of the lipid degradation during storage of ripened sausages. In particular, through both the sensorial analysis and through the analytical determination used, it has been possible to differentiate ripened sausages packed with a low concentration in CO2 (ATM3), characterized by a higher level of the parameters linked to the lipid fraction degradation, from those packed in atmospheres richer in CO2 (ATM1 and ATM2).

An experimental investigation was carried out to assess the effect of the packaging atmosphere composition on the evolution of volatile compounds in ripened sausages during storage. To the aim, three atmosphere compositions, characterized by different N2:CO2 ratio (ATM1, 70:30; ATM2, 80:20; ATM3 95:5) were applied for the packaging of ripened sausages. All the packed, not-sliced, sausages were stored in the dark at 4°C for 5 months. The determination of volatile compounds by SPME/GC/MS was carried out on the samples after each month of storage. The obtained results pointed out that the majority of volatile compounds resulted significantly related to the storage time variable more than to the atmosphere variable. However, some volatile compounds, derived from the lipid auto-oxidation such as nonanoic acid and octanoic acid, were significantly influenced by the atmospheres composition, with values that were lower in ATM1.

Accelerated oxidation tests are often used in shelf-life studies and evaluation of technological changes. The aim of this work was to compare, in an accelerated oxidation test on oil/water emulsions, three oxidation promoters, having different mechanisms of action and adjusted in order to provide similar oxidation rates. The results showed that, though the rates of increase of oxidized triacylglycerols were actually similar, the evolution of the volatile profile of the emulsions was quite different according to the different promoters. The radical promoter favoured the tracylgycerol decomposition and the further oxidation of volatiles. It was not selective against the different fatty acids, either. The metallic promoter mainly involved the polyunsaturated fatty acids, more susceptible to the oxidative phenomena, in spite of their relative abundance. The test at 50 °C presented a slight delay in the evolution of the volatile pattern.

The influence of the storage time on the levels of thermo-oxidation compounds of extra virgin olive oil (EVOO) during frying was evaluated. To this aim, two extra virgin olive oils (cv Bosana, EVOO1 and cv Semidana, EVOO2) fresh and after storage, were used, for deep-frying of potatoes. EVOO stored for a longer time led to a significant increase of the TAGP and ox-TAG content in both the residual fried oils and the oil extracted from potato chips, with respect to the levels observed when frying was performed with oils stored for a shorter time.

Various studies are present in literature about the nutritional and sensorial characteristics of preserved tomato products and minimally processed products. To the best of our knowledge, there are no data in literature concerning the tomato-based pâtés, suitable as seasoning for pasta, salads and sandwiches. The aim of this work was to characterize two types of tomato-based pâtés in terms of volatile compounds profile, lipid fraction degradation and antioxidant contents as a function of the ingredient formulation. The tomato-based pâtés showed a different aromatic profile, with particular reference to volatile compounds deriving from the raw materials and lipid autoxidation. Significant differences were also observed for the oxidative and hydrolytic degradation level of the lipid fraction, as well as total phenols and flavonoids content. The differences observed were linked to the ingredient formulation used. In particular, the addition of minced mushrooms, chilli and parsley involved a development of terpenic volatile compounds, while when extra virgin olive oil was used significantly higher percent contents of aldehydes and ketones were found, as well as a minor oxidative degradation of lipid fraction. Also total phenols and flavonoids content were influenced by the ingredient formulation, while no differences were observed for the lycopene content.

The literature contains several papers dealing with the volatile constituents contributing to the aroma of fresh and processed tomatoes. Along with the traditional tomato-based products, tomato-based pâtés, characterized by complex ingredient formulations, are commonly consumed as a seasoning for pasta, and as a dressing for meats, salads, and sandwiches. To the best of our knowledge, no investigations have been published on the influence of thermal stabilization treatments on the composition of volatile compounds in tomato-based pâtés. To this aim, thermally stabilized and not stabilized tomato-based pâtés were subjected to the analysis of volatile compounds. The results obtained highlighted the influence of the thermal stabilization process on the evolution of volatile composition tomato-based pâtés. In particular, the terpenic compounds showed significant decreases after the thermal stabilization process treatment, due to their degradation and oxidation favored by high temperatures. The thermal stabilization caused, moreover, an increase in volatile compounds deriving from lipid oxidation and Maillard reaction, characterized by low-sensory thresholds, and from the thermal degradation of carotenoids and fresh tomato-derived compounds. © 2013 Institute of Food Technologists®.

Background: The nature of the relationship between differential scanning calorimetry thermal properties and the oxidation and hydrolysis compounds formed during a real auto-oxidation process in virgin olive oils has not been evaluated so far, as these samples are difficult to find. In this work, 21 samples of virgin olive oil, stored under ideal conditions since their years of production (production range 1991-2005) to develop the natural auto-oxidation process, were analysed in order to evaluate this relationship. Results: Oils stored the longest time showed the highest hydrolytic degradation while the others exhibited higher contents of oxidised fatty acids and triacylglycerols, instead. Thermal properties of transitions were differently influenced by degradation compounds with the onset of both the cooling and heating profiles particularly influenced by diacylglycerols and oxidised lipids. Chemical data and thermal properties were correlated by using principal component analysis. Twenty-three variables were selected for the analysis with the first component fully segregating samples into two groups according to the year of storage and the level of hydrolysis and/or oxidation, on the basis of selected thermal properties obtained by cooling and heating transitions. Conclusions: These preliminary findings showed that differential scanning calorimetry could be considered an useful tool to evaluate lipid degradation in virgin olive oils, indicating its value as a support to chemical techniques. © 2013 Society of Chemical Industry.

An experimental investigation was carried out in order to verify the influence of monoacylglycerols on the oxidative processes in different vegetable oils. With this aim, three oils (soybean, sunflower, peanut) were purified in laboratory, added with 0.5% and 1% of monoacylglycerols obtained in purity by purified soybean oil and submitted to accelerated oxidation at 60°C for 10 days. The results showed that monoacylglycerols slowed down the rate of oxidation when added to sunflower oil and peanut oil, while they acted as pro-oxidants in soybean oil, showing therefore a different behavior depending on the fatty acid composition of the oils they are added to.

An experimental investigation was carried out in order to assess the influence of the cultivar and of the oil extraction process on the evolution of the oxidation compounds in extra virgin olive oil during frying. In order to do this oils from two Sardinian cultivars, obtained by two different oil extraction processes have been used to fry potato chips. The oils extracted from the potato chips were analyzed to evaluate the oxidative degradation and the antioxidant capacity. The results obtained showed that the differences observed for the oxidation triacylglycerol and polar compounds content in the extracted oils reflect the differences observed in the starting oils, while, as regards the triacylglycerol oligopolymers, the oils showed a different behavior during frying, indicating a slower polymerization rate in the oils characterized by a better quality.

An experimental investigation was carried out in order to evaluate the influence of deodor-ization temperature on the levels of the triacylglycerol oxidation and polymerization compounds in the deodorized oil. The deodorization was carried out at temperatures between 180 and 240°C, using a laboratory-scale pilot plant. The results showed an increase of triacylglycerol oligopolymers (PTAG) and a decrease of the levels of oxidized triacylglycerols (TAG-ox) as the deodorization temperature increased. Also a significant increase in the overall non volatile oxidation level, which can be evaluated with the sum PTAG% + TAG-ox%, was observed as a consequence of the increase of the deodorization temperature. The presence of lower levels of TAG-ox in the oils deodorized at higher temperatures may result in an improvement of oxidative stability in the resulting oil, since the pro-oxidant activity of TAG-ox has been shown to be greater than that exerted by PTAG.

The aim of this paper is to offer a comprehensive overview of the evolution of the national and European legislative framework regarding the commercial classes of olive oils. The earliest rule in Italy dates back to 1890, while the current commercial classes have been set by the EEC Regulation 2568/91 and its further several amendments. Finally, future trends for European Regulations have been proposed.

An investigation was carried out on the effect of adding increasing amounts of monoacylglycerols (MAG) - obtained from a purified soybean oil (PSO) - on the oxidation of the same PSO. PSO and the MAG/PSO solutions were subjected, during accelerated oxidation at 60°C, to routine analyses and High-Performance Size-Exclusion Chromatography of polar compounds. The addition of low amounts of MAG (5-10 g kg -1) caused an increase of oxidation. Adding higher amounts of MAG, the pro-oxidant effect progressively decreased. The solution containing 30 mg kg -1 showed the lowest oxidative levels. Therefore, the effect of MAG in PSO oxidation is not univocal, being dose-dependent.

Among the compounds deriving from lipid degradation considerable importance should be given to the products of triacylglycerols hydrolysis, as well as those arising from oxidation. It was shown, in fact, that some of these compounds could have pro-oxidant activity, and therefore affect the shelf-life of foods and their nutritional value, with obvious implications to the consumers' health. The aim of the present research was to evaluate the role of partial acylglycerols and free fatty acids on the evolution of oxidation in vegetable oils. At the purpose, purified diacylglyerols, monoacylglycerols and free fatty acids were added in percent amounts between 0.25% and 3% to vegetable purified oils prepared in laboratory; the mixtures obtained were subjected to Rancimat test. The results showed a different behavior towards the oxidative stability of oils of the different partial acylglycerols considered.

In previous investigations natural antioxidants were proven to be effective in slowing down oxidative processes in breakfast cereals and limiting, as a consequence, the onset of off-flavours during storage. The list of the ingredients, on the other hand, is one of the aspects that can be taken in consideration in order to preserve the product properties during its shelf-life: the choice of a suitable packaging, in fact, should be considered with the same attention, since the extreme market segmentation lead to many different packaging solutions. The present work was aimed to investigate on the behaviour of natural antioxidants in breakfast cereals stored for 180 days in different commercial packages: a double-layer coextruded polypropylene bag and a high density polyethylene bag combined with a cardboard box. Qualitative descriptive sensory analysis was performed on these products. The results obtained showed interesting interactions between antioxidant and packaging: the polyethylene packaging sensibly improved the sensory properties of the product, acting in synergy with the employed antioxidants.

Background: The study of pro- and anti-oxidant compounds is important for their influence on the shelf-life and nutritional value of food. The aim of this research was to evaluate the activity of monoacylglycerols (MAG), obtained by partial saponification of a purified olive oil, added in increasing amounts to the same oil and submitted to the Rancimat test and oven test at 60 C. Besides routine analyses, high-performance size exclusion chromatography analysis of polar compounds was performed. Results: The addition of MAG led in all cases to a significant slowdown of the oxidative processes. These trends were more evident as the oxidation went on. The purified oil added with 30 g kg-1 of MAG after 9 days of oven test at 60°C presented a level of oxidative degradation significantly lower than the control after only 4 days. Conclusion: The data showed a marked antioxidant effect of MAG in purified olive oil, contrary to what has been observed by other authors, who noticed either a pro-oxidant or a non-antioxidant activity of these compounds in soybean oil. A different behaviour of MAG during oxidation could depend on the different fatty acid composition of the oil matter they are added to. © 2010 Society of Chemical Industry.

BACKGROUND: There is little information in the scientific literature on the degradation of the fatty fraction of biscuits during storage. Thus two trials were performed utilizing two different kinds of margarine for a better evaluation of the phenomenon. RESULTS: Covariance analysis of the data evidenced a significant increase of the oxidized triacylglycerols (P < 0.001), together with a significant decrease (P < 0.001) in the amount ofmonounsaturated and polyunsaturated fatty acids. On the other hand, the level of hydrolytic degradation did not show significant variation. CONCLUSION: Principal components analysis ascertained that about 60% of the variance of the data could be attributed to the quality of the margarine, while about 30% was ascribable to the increase of oxidative degradation induced by storage. © 2009 Society of Chemical Industry.

In 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.

An experimental investigation was carried out to assess the quality of the lipid fraction of mortadella, focussing on the role of the lipid fraction in defining the nutritional and health characteristics of this product. The data obtained from the evaluation of the hydrolytic and oxidative degradation showed high variability among the samples. In particular, the high level of hydrolytic degradation observed in some samples could be related to the use of frozen lard, partially degraded, while an intense oxidative degradation could be related to the cooking treatment performed in the production of mortadella. The determination of the fatty acid composition revealed values of PUFA/SFA and n-6/n-3 PUFA ratios far from those recommended by nutritionists but comparable to the values reported in the literature for other meat-based products.

In this paper, the possibility to evaluate the oxidative phenomena and the quality of extra virgin olive oil of different cultivars (Coratina and Ogliarola) by means of HPSEC analysis of polar compounds matched with multivariate statistical analysis, has been considered. The obtained results pointed out that the oxidized triacyiglycerols were correlated in a positive way with some analytical indexes measuring the primary oxidation level of the oil, and in a negative way with compounds which concentration significantly decreases during the early stages of oxidation. The triacylglycerol oligopolymers, instead, were positively correlated with some parameters which allow to assess the secondary oxidative degradation of an oil, and in a negative way with some minor compounds, which level significantly decreases in oils being in advanced oxidative conditions. Therefore the determination of oxidized triacyiglycerols and triacylglycerol oligopolymers could be used as an alternative to the methods foreseen by EC regulations, thus allowing to reduce the number of analytical determinations.

Four different type of "focaccia" (Italian flat bread) prepared with the same dough and the same extra-virgin olive oil but with different flavourings, were analyzed. The flat breads were cooked in baker's oven at 220°C for 20 minutes. Lipids were extracted from each sample in laboratory using the Folch method. Further than the indices commonly used to assess the oil quality, non-conventional analytical parameters, like the amount of polymerization, oxidation and hydrolysis compounds, were determined on all samples to better assess the degree of oxidation and hydrolysis of the oils. Silica gel column chromatography and high-performance size exclusion chromatography (HPSEC) were the analytical techniques employed. The experimental data showed that, at the end of the baking, the oil extracted from all samples could not be included in virgin category on the basis of the official methods of analysis. The level of oxidation increased in all samples respect to the crude oil and moreover in all samples oligopolymers of triglycerides were present. The degradation level seems to be influenced by the flavourings employed to make the flat breads.

The pro-oxidant activity played by oxidised lipids in edible oils has already been reported in literature. However, it is still unknown whether all the classes of compounds due to oxidation and polimerisation, present in the oxidised fraction of a fat, have an equivalent pro-oxidant activity or if this activity is mainly performed by some of them. The aim of this research was that of evaluating the pro-oxidant effect of one of these classes, always present in refined oils, represented by the oligopolymers of oxidised triglycerides. Silica gel column chromatography was used to obtain the polar compounds (PC) from a thermo-oxidised oil, while preparative gel permeation chromatography of PC was carried out for separating and collecting the oligopolymers of oxidised triglycerides. A purified oil (not containing products of oxidation and hydrolytic degradation as well as free of pigments and substances having antioxidant activity) was prepared in laboratory with the aim to evaluate the pro-oxidant effect without interferences. The addition to the purified oil of variable percentages of polar triglyceride oligopolymers, in a range comprised between 0.25 and 1.0 %, fully evidenced the pro-oxidant activity of this class of compounds.

The effect of coadjuvants during olive oil processing on the oxidative enzymes and the content of fatty acid alkyl esters (FAAE) has been investigated. Two Italian olive cultivars, at different ripening degree, were processed immediately after harvesting or after 5 and 12 days of storage. The results highlighted a general decrease of FAAE and a significant increase in the PPO and POD activities due to the coadjuvant use. The increased oxidases activity could lead to a reduction of oils phenolic compounds.

Recently, the quantification of fatty acids alkyl esters has become mandatory for the extra virgin olive oil classification. However, the behaviour of such metabolites, during olives processing, is not yet well understood. Thus, the present paper aims to point out the influence of the use of calcium carbonate on the fatty acids alkyl esters content of the oils. The results showed that the content of fatty acids alkyl esters was significantly influenced by the technological coadjuvant. The use of calcium carbonate led to a general reduction of fatty acids alkyl esters compared to the untreated samples. Methyl esters of fatty acids were more susceptible to the use of processing aid than the ethyl esters.

The aim of the study was to assess the influence of talc on the extra virgin olive oil volatile profile during production and storage. The obtained results showed that talc used at 1% level did not cause significant differences, whereas at 2% level showed only slight differences were revealed compared to control. During storage a significant increase of the volatiles deriving from the oxidative process was observed and a concomitant significant decrease of the C6-LOX aldehydes. The evolution of the volatile compounds of extra virgin olive oils during storage was not significantly influenced by talc addition, with the exception of the sum of C6-LOX aldehydes, which showed a significant higher decrease.