1,814 research outputs found

    Influence of cold storage time on the softening prediction in Spring Bright nectarines

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    With Time-resolved Reflectance Spectroscopy (TRS) the maturity of nectarines at harvest can be assessed by measuring the absorption coefficient at 670 nm (µa 670) in the fruit flesh. A kinetic model has been developed linking the optical properties as measured by TRS with the models of µa 670 and firmness decay in shelf-life at 20°C, making the prediction of the softening time for individual fruit possible. In order to study the influence of cold storage time prior to shelf life on the softening prediction, 540 (year 2003) and 870 (year 2004) ‘Spring Bright’ nectarines were measured at harvest with TRS; then fruit were put in shelf life after various periods of cold storage at 0°C (4 and 10 d, year 2003; 6, 13 and 20 days, year 2004). During the 5-day period of shelf life at 20°C, fruit were analysed for firmness by pressure test after 30, 48, 54, 72, 78, 96, 102 and 120h in 2003 and after 36, 43, 62, 87, 108 and 135h in 2004. For each year and cold storage time, the parameters of the logistic model of softening as a function of µa 670 at harvest were computed. The cold storage up to 13 days did not significantly influence the estimates of the softening rate constant (kf), of the maximum firmness at minus infinite time (Fmax) and of parameter alpha (a) in both years, whereas parameter beta (ß) in 2003 significantly decreased from -1.867 at day 4 to -2.237 at day 10. The further 7 days of cold storage in 2004 significantly affected kf, which decreased from 0.00084 at days 6 and 13 to 0.00069 at day 20, and ß which increased from -2.395 at day 6 to -2.053 at day 20. Our results indicate that the cold storage time significantly influences the softening prediction of nectarines as the longer the cold storage, the lower the softening rat

    TRS-measurements as a nondestructive method assessing stage of maturity and ripening in plum (Prunus domestica L.)

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    n plum fruit with dark red or blue blush colour covering the whole fruit, the change in ground colour from green to yellow during maturation and ripening is masked. Hence, the maturity stage is difficult to judge. Time-resolved reflectance spectroscopy (TRS) has been used as a nondestructive method to assess changes in important internal quality factors in ‘Jubileum’ plums (Prunus domestica L.). Absorption coefficients (µa) and scattering coefficients (µs) were measured at both 670 and 758 nm during 5 days of storage. The changes in soluble solids content, titratable acidity and firmness were as expected. No change in soluble solids content was observed, while the plums became less acid and softer during storage. The TRS-measurements of plums indicated that TRS could give interesting information on internal quality factors in plums as the absorption at 670 nm was closely related to firmness, TA and TSS at the time of picking. Absorption at 758 nm was more closely related to the quality parameters after storage. The study did not indicate that scattering could be used in assessing maturity stage in plum

    The Population ageing in Italy: facts and impact on household portfolios

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    This paper aims to assess the impact of ageing on household portfolios in Italy and hence ultimately on financial markets. To this end, the analysis is carried out in two steps. First, the dimension of population ageing in Italy is assessed by means of both historical and forecast data on the structure of Italian population. Second, based on data taken from the Bank of Italy Survey of Household Income and Wealth (SHIW) over the last decade, we analyse the average household portfolio in relation to demographic characteristics. The main findings are: first, Italy turns out to be one of the countries most affected by ageing; second, financial choices of Italian households are sensibly affected by age. Thus, the exceptional ageing in Italy might have relevant consequences on the Italian financial market

    Optical Absorption and Scattering Phenomena in 'Jubileum' Plums in Relation to Their Colour Properties

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    Absorption and scattering of laser light pulse passing through the fruit determine among others, the optical properties of the product. Efforts have been made in the recent past to utilize innovative techniques such as time-resolved reflectance spectroscopy (TRS) to study the quality aspects of different fruit such as nectarines. These optical properties have been well related to firmness, sugars, acids and other quality attributes. TRS measurements were performed on ‘Jubileum’ plums at two different wavelengths: 670 nm and 758 nm. The fruit were harvested in Norway and brought to Italy under protected conditions. After sorting the fruit by size, TRS measurements were made and the fruit were randomized for different examinations of quality aspects. It was observed that the absorption coefficient (µa) increased for both wavelengths as ripening progressed towards the melting stage of the fruit. The µa values at 670 nm were higher than those at 758 nm. The higher rate in the µa was distinguishable from the third day onwards as the fruit ripened. Similarly, it was interesting to note that the internal colour measured after destructing the fruit related well with the TRS absorption coefficient (µa), i.e., a decrease in the CIE L* (towards darker region) and b* (towards blue) value along with an increase in a* (towards red) from third day of storag

    Sensory profiles of various stored fruit species are affected by maturity class assessed by time-resolved reflectance spectroscopy at harvest

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    The absorption coefficient measured at harvest at 670 nm (μa670) by timeresolved reflectance spectroscopy (TRS) is a non-destructive maturity index used to evaluate the biological age of fruit, i.e., the fruit maturity stage. The μa670 was successfully used to classify nectarine, apple and mango fruit into maturity classes each one having distinctive ripening behaviors. Aiming at studying the influence of TRS maturity class assessed at harvest on the sensory profiles of various fruit species after storage, 'Jonagored' apples, 'Abbé Fétel' pears, 'Morsiani 90' nectarines and 'Spring Belle' peaches were measured at harvest by TRS at 670 nm, ranked on the basis of decreasing μa670 (increasing maturity) and classified as less (LeM), medium and more (MoM) mature. Then fruit were randomized into batches of 30 fruits, each one corresponding to a storage atmosphere (apples: CA, NA; pears: CA, NA, DCA) or to a storage temperature (peaches, nectarines: 0, 4°C). After storage, fruit were put in shelf life at 20°C to reach the ripening degree for consumption. Sensory analyses (QDA profiles) were carried out on LeM and MoM fruit using a panel of 10 assessors. Our results indicate that, for all the species, besides the influence of storage conditions, there was also a great influence of TRS maturity classification at harvest. MoM apples and pears developed physiological disorders such as mealiness and graininess when stored in NA, whereas showed well balanced sensory characteristics when stored in CA and DCA, becoming after storage soft, juicy, sweet, but sour enough. MoM nectarines stored both at 0 and 4°C became woolly, while the LeM ones stored at 0°C developed the best sensory characteristics. MoM peaches stored at 0°C showed the best sensory profile and the LeM ones stored at 4°C the worst. So TRS maturity classification at harvest can give indications on the best storage conditions in order to obtain fruit with sensory characteristics than can satisfy the consumer

    Linking food web functioning and habitat diversity for an ecosystem based management: A Mediterranean lagoon case-study

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    We propose a modelling approach relating the functioning of a transitional ecosystem with the spatial extension of its habitats. A test case is presented for the lagoon of Venice, discussing the results in the context of the application of current EU directives. The effects on food web functioning due to changes related to manageable and unmanageable drivers were investigated. The modelling procedure involved the use of steady-state food web models and network analysis, respectively applied to estimate the fluxes of energy associated with trophic interactions, and to compute indices of food web functioning. On the long term (hundred years) temporal scale, the model indicated that the expected loss of salt marshes will produce further changes at the system level, with a lagoon showing a decrease in the energy processing efficiency. On the short term scale, simulation results indicated that fishery management accompanied by seagrass restoration measures would produce a slight transition towards a more healthy system, with higher energy cycling, and maintaining a good balance between processing efficiency and resilience. Scenarios presented suggest that the effectiveness of short term management strategies can be better evaluated when contextualized in the long term trends of evolution of a system. We also remark the need for further studying the relationship between habitat diversity and indicators of food web functioning

    Who holds the purse strings within the household? The determinants of intra-family decision making

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    We study the determinants of intra-household decision-making responsibility over economic and financial choices using a direct measure provided in the 1989–2010 Bank of Italy Survey of Household Income and Wealth. We find that the probability that the wife is responsible for decisions increases as the wife’s characteristics in terms of age, education and income become closer or even higher than those of her husband’s. Thus, consistently with a bargaining approach, decision-making responsibility is associated with marriage heterogamy, and not only along strictly economic dimensions. However, in support of an alternative household production approach, we also find that the probability that the wife is responsible is lower when she is employed, which suggests the presence of a specialization pattern assigning responsibility to the spouse with more available time. Our results are robust to additional controls and alternative samples
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