Sensory Attributes Driving Preference for Wild Rocket (Diplotaxis tenuifolia) Leaves Tasted as a Single Ingredient and as a Part of a Recipe.

Two cultivars of wild rocket (Diplotaxis tenuifolia), cv. Denver and Marte, were subjected to chemical determination of flavour-related constituents, sensory descriptive analysis, and measurement of liking by consumer test. Consumers evaluated rocket leaves both as a single ingredient and in a recipe formed by a roll of bresaola with also Grana Padano cheese. Sensory analyses showed that Marte was characterized by a more intense bitterness, hotness, and pungency, which corresponded to a higher total GSL content, mainly due to a higher level of dimeric 4-mercaptobutyl GSL. Five clusters of consumers were identified based on their liking scores. When tasting rocket leaves as a single ingredient, three clusters showed a higher liking for the milder cultivar, one cluster showed an opposite preference, while flavour attributes, such as bitterness and hotness, appeared as the main drivers of liking. Differences in liking were no longer found between the two cultivars when rocket leaves were evaluated in the recipe. Therefore, as rocket leaves are generally consumed as a part of a recipe with other ingredients instead of as a single ingredient, in the assessment of consumer preferences, it should not be neglected the influence of the way in which the product is consumed.

Chemical, microbiological, textural, and sensory characteristics of pilot-scale Caciofiore cheese curdled with commercial Cynara cardunculus rennet and crude extracts from spontaneous and cultivated Onopordum tauricum.

The aim of this study was the chemical, microbiological, textural, and sensory characterization of pilot-scale prototypes of an Italian ewe's raw milk cheese (Caciofiore) curdled with commercial Cynara cardunculus rennet, used as a control, and crude extracts obtained from flowers of either spontaneous or cultivated Onopordum tauricum. Hence, the control and experimental cheese prototypes produced in two rounds of cheesemaking trials were assayed, at the end of their 60-day maturation, for the following features: pH, titratable acidity, dry matter, fat, total and soluble nitrogen (TN and SN, respectively), ash, salt, protein, lactose, viable plate counts and composition of the bacterial and fungal populations, color, texture, volatile organic compounds (VOCs), and olfactory attributes by sensory analysis (the latter for the sole prototypes curdled with the commercial rennet and the extract obtained from cultivated O. tauricum). The data overall collected showed a very low impact of the type of thistle rennet on the analyzed cheese traits, with significant differences being exclusively found for SN/TN%, titratable acidity, color, and adhesiveness. By contrast, a higher impact of the cheesemaking round was seen, with significant differences being observed for salt content, load of presumptive lactobacilli, thermophilic cocci, and Escherichia coli, and levels of the following VOCs: 2,3-butanedione, 2-pentanone, 1-butanol, 2-heptanone, 3-methyl-1-butanol, 2-heptanol, 2-nonanone, dimethyl trisulfide, 2-methyl propanoic acid, butanoic acid, and 3-methyl butanoic acid. Sensory analysis revealed a strong ewe's cheese odor, accompanied by other olfactory notes, such as pungent, sour curd, sweet, and Parmesan cheese-like notes, in all the analysed cheese prototypes. Moreover, key odor active compounds, including butanoic acid, ethyl butanoate, 2,3-butanedione, 1-octen-3-one, and dimethyl trisulfide, were identified by GC-olfactometry analysis. Regarding the odor attributes as determined by sensory analysis, again the type of rennet had an almost negligible impact, with significant differences being only perceived for 1 or 2 out of 20 odor attributes, depending on the analytical conditions applied. Although some aspects deserve further investigation, the results herein collected confirm that O. tauricum can be regarded as an alternative source of thistle rennet for the manufacture of Caciofiore cheese, and more in general, Mediterranean ewe's milk cheeses.

The Fate of the Chlorophyll Derivatives in Olives Preserved and/or Packaged in Presence of Exogenous Copper.

Chlorophyll pigments are thought to be responsible for the highly appreciated green color of unfermented Castelvetrano-style table olives, but no studies have considered the effects of a controlled addition of copper during storage or packaging at the industrial level. For this purpose, chlorophyll derivatives were analyzed in Nocellara cultivar table olives debittered industrially using the Castelvetrano method, via means of HPLC and MS analyses, following the addition of copper in alkaline brines stored at 4 °C for 3 months in 220 L barrels, and during the subsequent storage in acid brines in commercial 400 g packages at 4 °C for up to 18 months. The presence of copper in storage or in packaging brines both contributed significantly to maintaining the green color of the olives, which was associated with a specific pattern of chlorophyll derivatives, as evidenced by principal component analysis. Notably, re-greening was rapidly achievable also for olives that had yellowed for 18 months at a copper concentration below the limit of EU legislation. Finally, by means of PCA, we also demonstrated that a short-term thermic treatment can work as an accelerated predictive tool in determining the fate of chlorophyll derivatives.

Exploring volatile aroma and non-volatile bioactive compounds diversity in wild populations of rosemary (Salvia rosmarinus Schleid.).

Ninety-five rosemary (Salvia rosmarinus Schleid.) genotypes, representing 24 wild populations, collected in different geographical areas in Italy and then cultivated under homogeneous environmental conditions, were characterised for volatile organic compounds (VOCs) and three main non-volatile phenolic diterpenes (carnosic acid, carnosol) and acids (rosmarinic acid). Cluster analysis of chemical data highlighted the occurrence of three main groups of populations: one with high levels of verbenone, α-pinene, bornyl acetate, carnosic acid and carnosol, a second one with relatively high levels of camphor and a third one with high levels of 1,8-cineole, ß-pinene and sesquiterpenes. This clustering was consistent with geographic origin and previous genetic characterisation of the same populations. Correlation analysis suggested that levels of the key antioxidant carnosic acid were associated to levels of the key aroma compound verbenone. The observed diversity may be exploited in breeding programs to develop lines and designing products with improved flavour quality and functional properties.

Comparative Study of Bioactive Compounds and Biological Activities of Five Rose Hip Species Grown in Sicily.

Nowadays, research on plant extracts has attracted increasing interest. The aim of this study was to compare phenolic profile, vitamin C, and carotenoid content, as well as the biological activities of five different rose species, including Rosa canina, R. corymbifera, R. micrantha, R. rubiginosa, and R. rugosa. These species had different morphological characteristics, with R. rugosa showing higher size of flower petals and higher weight of hips. The highest vitamin C content was found in hip extracts of R. rubiginosa and R. rugosa, which also showed the highest carotenoid amount. R. corymbifera showed the highest phenolic content. No significant antimicrobial activity of extracts containing phenolic compounds against different indicator strains could be detected. Cell monolayer integrity was not affected by treatments with the above-mentioned extracts of R. canina, R. micrantha, and R. rugosa at different concentrations for up to 24 h, while those of R. rubiginosa and R. corymbifera affected intestinal permeability at the highest concentration tested. The partial least squares regression analysis generated a predictive model correlating phenolic compounds with cell monolayer integrity, suggesting a relevant role for catechin, quercitrin, and p-coumaric acid. In conclusion, this study highlights how rose hips belonging to different species can have a diverse phenolic profile, differently influencing intestinal monolayer integrity.

Effect of the use of anti-hail nets on codling moth (Cydia pomonella) and organoleptic quality of apple (cv. Braeburn) grown in Alto Adige Region (northern Italy).

BACKGROUND: The anti-hail nets are widely used to protect apple fruit against hailstorms and hail damage. They can have also beneficial effects against pests in apple orchards, in particular codling moth (Cydia pomonella). However, covering the trees with anti-hail nets can modify the orchard microclimate and reduce the interception of light, thus potentially causing negative consequences on the organoleptic quality of apple fruits. RESULTS: A consistent reduction of the percentage of apple fruits infested by codling moth was registered as a result of the use of anti-hail nets during two consecutive harvest years. Their use did not affect fruit maturity, but reduced the skin colour, sugar content, pulp total phenol content, volatile compound composition and sensory characteristics. However, the results were inconsistent over the two years apart for total phenols, formation of two volatile compounds (butyl and hexenyl acetate, the first being one of the main odorants in most apple cultivars), sensory attributes of 'flavour of lemon' and 'juiciness'. For these parameters, the fruits from plots where the trees were not covered showed higher values than those from plots where anti-hail nets were used. CONCLUSIONS: The use of anti-hail nets was effective in preventing the attack of codling moth to apple fruits, suggesting their use in organic management where conventional insecticides are prohibited. Under the conditions tested, anti-hail nets showed a negative effect on some of the quality characteristics measured on apple fruits, which could influence consumer acceptability.

Impact of different distribution scenarios and recommended storage conditions on flavor related quality attributes in ripening fresh tomatoes.

Tomato (Solanum lycopersicum) fruits of three cultivars picked at different ripening stages were subjected to conditions in the laboratory simulating both short and long distribution chains as occurring in commercial practice and to recommended storage conditions. At the end of the postharvest experiments, a flavor quality profile of fruits was obtained by chemical determination of volatile compounds, sugars, and organic acids, and physical measurement of texture properties. In two of the three cultivars, the overall profile and many of the individual quality attributes was significantly affected by the distribution chain conditions, the effect being more pronounced in tomatoes marketed at full ripeness than in those marketed at an intermediate ripening stage. In these cultivars, tomatoes harvested at the Breaker stage, subjected to long chain conditions and then allowed to achieve full ripeness at room temperature, did not develop the same overall profile observed on fruits fully ripened on the vine and exposed to a simulated short chain. Fruits subjected to recommended commercial storage conditions, cold stored above the chilling range (10 or 13 °C) and at high relative humidity (95%), developed a different profile when compared to fruit exposed to the simulated long distribution chain (6 °C and 55-80% RH), suggesting that these changes in temperature and relative humidity may remarkably affect flavor formation in tomato fruits. Major drivers of profile differentiation between tomatoes subjected to different postharvest scenarios were the levels of some aroma compounds derived from aminoacids (1-nitro-2-phenylethane, 2-isobutylthiazole, phenylacetaldehyde, 2-phenylethanol, and 2- and 3-methylbutanal) and lipids ((E,E)- and (E,Z)-2,4-decadienal), and, among nonvolatile flavor compounds, of organic acids (citric and malic).