PTR-ToF-MS fingerprinting of Italian EVOO

Extra Virgin Olive Oil (EVOO) is the highest quality olive oil available, extracted from the olive fruit without the use of any heat or chemicals. Among the high quality EVOOs recognized by the European Union (Protected Designation of Origin, PDO, and Protected Geographic Identification, PGI), almost the 40% come from Italy with 42 PDO and 4 PGI EVOOS followed by Spain and Greece having 29 recognized EVOOs each. Due to its economic value, high quality EVOO is susceptible to fraud. A high quality EVOO is distinguished for its aroma. Many factors influence the composition in Volatile Organic Compounds (VOCs) such as cultivar, agronomical practices, geographical origins, harvesting periods, processing technologies, storage conditions [1]. The study of volatile compounds could be a way to trace the origin and quality of EVOOs. The gold standard for this task is the use of GC-MS providing detailed information on VOCs profiling. On the other hand, such approach is not always a convenient and practical choice when dealing with large sample set (time and cost consuming). Fast fingerprinting can be a valid alternative, at least as screening tool, to characterize a population fast. Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) was already successfully applied for screening of olive oils [2], apples [3], and other food products allowing a fast screening of large sample set. In the present study, we applied PTR -ToF-MS to obtain a fast VOCs fingerprint of high quality EVOO samples collected within the Violin project (Project AGER2-Rif.2016-0169). Up to now, 200 EVOOs (monovarietals and blends) from 12 Italian regions and three other countries, harvested in two different years, were measured. Preliminary data elaboration suggests the possibility to discriminate EVOOs according to the origin. For example, EVOO from Sicily seems to present a peculiar fingerprint that allows a separation from all other EVOO analyzed to be achieved. On a reduced dataset (for which a sufficient number of samples per each location was available), including EVOOs from Apulia, Sicily, Lazio, and Tuscany, classification models based on Partial Least Squares Discriminant Analysis (PLS-DA) were tested

Analysis of some recharge solutions on varying the R407C composition

In the vapour compression plants possible leaks can vary the composition of a zeotropic refrigerant mixture. The main aim of this paper is to verify experimentally if the plant performances are restored with a proper recharge, when leaks are imposed. As for the R407C mixture the percentage of the less volatile component (R134a) increases, while the percentage of the more volatile components (R32 and R125) decreases when leaks occur. The experimental tests have been realized determining refrigerant leaks from the liquid receiver placed at the condenser outlet and measuring the properties in steady state condition. The recharge is realized in different ways: with R407C, with R134a and R410A or with R32 R125 and R134a. The different solutions are then compared from the economical point of view, in terms of COP, refrigeration power and air temperature at the evaporator outlet, adopting an iteration method. This method determines the real composition of a zeotropic mixture working in a compression plant, when only the temperature and pressure values at the expansion valve inlet and outlet are known

Refrigeration plant exergetic analysis varying the compressor capacity

The paper presents an exergetic analysis of a vapour compressor refrigeration plant when the refrigeration capacity is controlled by varying the compressor speed. The aim is performance evaluation of both the whole plant and its individual components. The analysis of the exergy flow destroyed in each device of the plant varying the compressor speed has been carried out in order to determine the relative irreversibility of the plant components. The vapour compression plant is subjected to a commercially available cold store. The compressor working with R22, R407C and R507 and designed for a revolution speed corresponding to 50 Hz supply current frequency, has been used varying the frequency in the range 30–50 Hz. In this range, the most suitable working fluids proposed as substitutes of R22, as R407C (R32/R125/R134a 23/25/52% in mass), R507 (R125/R143A 50/50% in mass) and R417A (R125/R134a/R600 46.6/50/3.4% in mass), have been tested. The variable-speed compressor is fitted with a pulse-width modulated source inverter (PWM) predominantly used in medium power applications due to its relatively low cost and high efficiency. The basic difference between variable speed refrigeration and conventional refrigeration systems is in the control of the system capacity at part-load conditions. The conventional refrigeration systems are characterized by compressor on/off cycles arising from by the thermostatic control. On the contrary when the inverter is used the capacity of the refrigeration system is matched to the load regulating the compressor motor speed. When the control of the compressor capacity is obtained by varying its speed there is an energy saving with respect to the thermostatic control. The best results of the exergetic analysis have been obtained using R22 followed by the non-azeotropic mixture designed as R407C that confirms, among the fluid candidates R22 substitution a better performance, shown also at the compressor nominal speed. Copyright © 2003 John Wiley & Sons, Ltd

Does the ‘Mountain Pasture Product’ claim affect local cheese acceptability?

This paper aims to explore the impact of “mountain pasture product” information on the acceptability of local protected designation of origin (PDO) cheese produced from the raw milk of cows grazing in mountain pastures (P) or reared in valley floor stalls (S). A total of 156 consumers (55% males, mean age 41 years) were asked to evaluate their overall liking on a 9-point hedonic scale of four samples: Cheeses P and S were presented twice with different information about the origin of the milk (cows grazing on mountain pasture or reared in a valley floor stall). Demographics, consumer habits, and opinions on mountain pasture practice (MPP), attitudes towards sustainability, and food-related behaviours (i.e., diet, food waste production, organic food, and zero food miles products purchase) were recorded and used to segment consumers. The cheeses were all considered more than acceptable, even though they were found to be significantly different in colour and texture by instrumental analyses. In the whole consumer panel, the cheese P was preferred, while in consumer segments less attentive to product characteristics, this effect was not significant. External information had a strong effect: Overall liking was significantly higher in cheeses presented as “mountain pasture product”, both in the whole panel and in consumer segments with different attitudes (except for those with a low opinion of MPP

Expanded Total Equivalent Warming Impact analysis on experimental standalone fresh-food refrigerator

The stand-alone refrigerators for fresh food storage represent a large part of supermarket refrigeration equip-ment. In these devices, the usage of refrigerants with low Global Warming Potential allows the mitigation of the direct emissions due to refrigerant leakages. In contrast, the indirect emissions in these components are highly dependent on the refrigerant charge, leakage, and equivalent emission factors related to the electricity pro-duction mix. The most used index to evaluate the environmental impact of refrigerators is the Total Equivalent Warming Impact. Despite that this index presents limits on the fixed evaluation of many parameters such as refrigerant charge, electricity consumption and, electricity emission factor. Otherwise in this study, an accurate evaluation of refrigerators emissions has been realised by using the innovative Expanded Total Equivalent Warming Impact method to an experimental stand-alone refrigerator by using a dynamic approach to evaluate direct and indirect contributions. The environmental analysis considers four different refrigerants and four different countries of location. The results show that the indirect emissions due to electricity consumption cover the highest share of emissions. In addition, the operating years affected by low refrigerant charges are respon-sible for emissions by greater than 25% compared to other ones. The hourly equivalent emissions due to elec-tricity consumption in countries characterized by an electricity generation mix mainly based on renewable and/ or nuclear plants show an indirect environmental impact up to 5 times lower than countries with a natural gas -based electricity production mix. The study also defines new strategies to reduce the environmental impact of the stand-alone refrigerator such as the use of photovoltaic systems combined with this technology or earlier maintenance processes that could determine an equivalent emission saving of up to 38%

A Comprehensive Energy Model for an Optimal Design of a Hybrid Refrigerated Van

The path towards decarbonization requires a progressive adaptation of all refrigeration systems, but only stationary ones have been intensely studied to improve their environmental performance. However, refrigerated transport is vital in the cold chain and must be considered in the green transition. In this paper, we propose a model for a hybrid refrigerated van that includes photovoltaic panels and electric batteries to decrease total greenhouse gas emissions from the engine. Thermal, electrical, and battery sub-models are considered and integrated into the comprehensive hybrid solar-powered refrigerated van model. Different technologies are compared, including lithium and lead-acid batteries and three different types of photovoltaic panels. The model was validated regarding van fuel consumption, showing a 4% deviation. Single and multiple delivery scenarios are considered to assess the energy, economic, and environmental benefits. Monthly CO2,e emissions could be reduced by 20% compared to a standard refrigerated van. Despite the environmental benefits provided by this sustainable solution, the payback period is still too long (above 20 years) because of the necessary investment to adapt the vehicle and considering fuel and electricity prices currently

Bioactivity of volatile organic compounds by Aureobasidium species against gray mold of tomato and table grape

Aureobasidium strains isolated from diverse unconventional environments belonging to the species A. pullulans, A. melanogenum, and A. subglaciale were evaluated for Volatile Organic Compounds (VOCs) production as a part of their modes of action against Botrytis cinerea of tomato and table grape. By in vitro assay, VOCs generated by the antagonists belonging to the species A. subglaciale showed the highest inhibition percentage of the pathogen mycelial growth (65.4%). In vivo tests were conducted with tomatoes and grapes artificially inoculated with B. cinerea conidial suspension, and exposed to VOCs emitted by the most efficient antagonists of each species (AP1, AM10, AS14) showing that VOCs of AP1 (A. pullulans) reduced the incidence by 67%, partially confirmed by the in vitro results. Conversely, on table grape, VOCs produced by all the strains did not control the fungal incidence but were only reducing the infection severity (< 44.4% by A. pullulans; < 30.5% by A. melanogenum, and A. subglaciale). Solid-phase microextraction (SPME) and subsequent gas chromatography coupled to mass spectrometry identified ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol as the most produced VOCs. However, there were differences in the amounts of produced VOCs as well as in their repertoire. The EC50 values of VOCs for reduction of mycelial growth of B. cinerea uncovered 3-methyl-1-butanol as the most effective compound. The study demonstrated that the production and the efficacy of VOCs by Aureobasidium could be directly related to the specific species and pathosystem and uncovers new possibilities for searching more efficient VOCs producing strains in unconventional habitats other than plant