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71.
Internet of things extends the capabilities to identify products with new technologies such as near field communication, radio-frequency identification, quick response code and with existing identification technologies such as barcode. Identification allows to retrieve extended information and knowledge of the products. Thereby, customers are able to retrieve and share knowledge among the different products. This work presents the participative marketing as the evolution from the social media marketing toward the active participation from the prosumers and the empowerment of the marketing with the collective intelligence. Thereby, participative marketing enables new interaction and participation models based on the ubiquitous identification. This has been evaluated in a social platform, which integrates the knowledge and experiences from the customers, and in a mobile platform, which interacts with the products through the mentioned identification technologies.  相似文献   
72.
Nectarine [Prunus persica (L.) Batsch] is a sought‐after fruit due to its properties. In addition, minimally processed produces are more and more accepted by consumers. Four nectarine cultivars (‘Early Top’, ‘Nectaprima’, ‘Big Top’ and ‘Venus’) were selected to study their suitability for minimal processing. Samples were processed in a clean room at 8 °C, washed them in water (4 °C) and stored at 4 °C in modified atmosphere packaging. The samples were analysed at 0, 3, 6 and 9 days of storage, and quality parameters as well as functional compounds (polyphenols and polyphenol oxidase activity) were studied. Principal component analysis (PCA) was carried out to assess the relationship between nectarine cultivars and determined parameters. In conclusion, ‘Early Top’ and ‘Nectaprima’ cultivars showed the best quality results and therefore a promising suitability for fresh‐cut processing. Nevertheless, the remaining cultivars should not be ruled out due to their functional content, advising additional conservation treatments for them.  相似文献   
73.
The potential health-improving effects of both a prebiotic and a probiotic infant formula have been evaluated in a rat model. Two groups of 10 rats were fed with either prebiotics containing fructo-oligosaccharides or probiotics containing viable Bifidobacterium lactis and Streptococcus thermophilus. The composition of their caecal microbiota was analyzed both by classical plate count of the main bacterial groups and by PCR amplification of a V3 fragment of 16S rRNA genes and denaturing gradient gel electrophoresis (DGGE). Both diets induced a significant reduction of clostridia and Bacteroides spp. compared to a control diet, whereas prebiotics were also able to reduce the number of coliforms and to increase the presence of bifidobacteria. DGGE analysis showed a significant increase of 16S rRNA gene fragments in rats fed with either probotics or prebiotics. Nineteen bands were sequenced and most of them showed similarity to cultured bacteria. Detection of Bifidobacterium spp. by this technique using genus-specific primers only permitted these bacteria to be detected in prebiotics-fed rats, whereas the use of Lactobacillus group-specific primers gave similar results in rats fed with any diet, in agreement with the plate count results.  相似文献   
74.
75.
The fermentation of natural black olives is currently carried out under anaerobic conditions. This work investigates the aerobic fermentation of this product in tanks containing 16 000 kg of Empeltre olives during two seasons. The microorganisms in brines were yeasts in all cases, whereas lactic acid bacteria growth was only observed in some tanks. Consequently, the pH during fermentation was in most cases higher than recommended 4.3 units. However, the Empeltre olive brines displayed bactericidal effect against Salmonella enterica, Sthapylococcus aureus, Escherichia coli and Listeria monocytogenes, with a 5 log population drop in one or 24 h depending on the brine age so that these olive brines are a harsh environment for the growth of these pathogens. It was found HyEDA as the major phenolic compound in both brine and olive pulp at the beginning of fermentation that slowly hydrolysed into hydroxytyrosol that reached a concentration up to 1500 mg kg−1.  相似文献   
76.
The effect of the natural components of dressing during the conservation of olives on their texture was studied. Significant differences in texture between preparations with and without dressing were detected, although the texture in both preparations continued to diminish with time of conservation until the difference between textures was eliminated. These facts suggest that the enzymes coming from the constituents of the dressing (garlic, lemon, etc), as well as those endogenous enzymes in the olive fruit itself influence the changes in the texture, the olive becoming more susceptible to dressing and to enzymatic action as the stage of maturation progresses. Changes in the composition of polysaccharides and significant decreases in texture were related. Degradation of important polysaccharides in the structure of cell walls, such as !-cellulose, carbonate-soluble pectin and 4% KOH-soluble hemicelluloses were detected. This noticeable degradation could be explained perfectly by the combined action of the cell wall degrading enzymes, cellulase and polygalacturonase, present.  相似文献   
77.
The distribution of sorbic and benzoic acids in the different phases of table olives was studied. To a large extent, these preservatives accumulated in the oil phase of fruits stored in acid conditions, as well as in juice and other tissue components. Thus, around 20–30% of the benzoic acid in olives was found in the juice phase, 30–50% in the oil phase and 30–40% in the rest of the olive flesh. Experiments carried out with black ripe olives revealed that an increase in pH of the medium gave rise to a decrease in the absorption phenomenon in whole olives and in the oil phase. As a consequence of this effect, benzoic acid could be leached from stored black ripe olives during the darkening process, although the calcium content of fruits greatly influenced the diffusion phenomenon. The results obtained in this study are important for future legal limitations of these preservatives in table olives and inhibition capacity of them in commercial table olives.  相似文献   
78.
New table olive genotypes (48) coming from a cross‐breeding programme were evaluated. Most of the fruit traits covered a wide range of variability on the set of genotypes, fruit weight (1.1–9.7 g), pulp‐to‐pit ratio (1.7–10.0), fruit shape (1.0–1.6) and oil content (1.3–15.2%). This is the first time that healthy compounds such as triterpenic acids and phenolic compounds have also been evaluated in olive progenies. Genotypes were stored for 2 months in sterilised brine (5% NaCl and 0.5% acetic acid). A high amount of maslinic (685.0–1394.2 mg kg?1 olive flesh) and oleanolic acids (275.3–817.9 mg kg?1 olive flesh) was found in the flesh of olives stored. The main oleosidic and phenolic compounds evaluated in brines were hydroxytyrosol (1.9–8.4 mmol L?1), hydroxytyrosol glucosides (0.4–19.8 mmol L?1), oleuropein (0.0–4.7 mmol L?1) and the antimicrobial compounds, dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol (0.0–3.4 mmol L?1) and decarboxymethyl elenolic acid (0.0–1.7 mmol L?1), the latter two being observed in only ten genotypes. The wide range of variation observed for most compounds indicates that the contents of these healthy compounds may be used as selection criteria in table olive breeding programmes.  相似文献   
79.
Boning of dry-cured hams involves additional handling which increases the risk of contamination with Listeria monocytogenes. This work studies the ability of E-beam to eliminate this pathogen from boned dry-cured ham (BDH). The destruction kinetics of four L. monocytogenes strains (S2, S4-2, S12-1, and S7-2) and L. innocua NCTC 11288 as a surrogate were determined at doses up to 3 kGy. L. innocua and L. monocytogenes S4-2 were the most radioresistant (D-value = 0.55 kGy). E-beam penetration was studied in blocks extracted from BDH and irradiated with 2–6 kGy. The bilateral treatment of 2 kGy allows the required dose (1.32 kGy) to be absorbed in the innermost part of the block to achieve the food safety objective of “zero tolerance” for this microorganism. This listericidal treatment was also confirmed in whole BDH intentionally contaminated with L. innocua. The sensory analysis of irradiated BDH showed off-odors that were imperceptible after 15 days of storage at 4°C.  相似文献   
80.
As Moore's law is running to its physical limit, tomorrow's electronic systems can be leveraged to a higher value by integrating “More than Moore” technologies into CMOS digital circuits. The hybrid heterostructure composed of two-dimensional (2D) semiconductors and molecular materials represents a powerful strategy to confer new properties to the former components, realize stimuli-responsive functional devices, and enable diversification in “More than Moore” technologies. Here, an ionic liquid (IL) gated 2D MoS2 field-effect transistor (FET) with molecular functionalization is fabricated. The suitably designed ferrocene-substituted alkanethiol molecules not only improve the FET performance, but also show reversible electrochemical switching on the surface of MoS2. Field-effect mobility of monolayer MoS2 reaches values as high as ≈116 cm2 V−1 s−1 with Ion/Ioff ratio exceeding 105. Molecules in their neutral or charged state impose distinct doping effect, efficiently tuning the electron density in monolayer MoS2. It is noteworthy that the joint doping effect from IL and switchable molecules results in the steep subthreshold swing of MoS2 FET in the backward sweep. These results demonstrate that the device architecture represents an unprecedented and powerful strategy to fabricate switchable 2D FET with a chemically programmed electrochemical signal as a remote control, paving the road toward novel functional devices.  相似文献   
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