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The role of water in food quality decay
2006
Piazza, L.
The impact of water on food thermodynamics and physics and, therefore, on its quality is more important than the one of any other food chemical component. When fundamentals of chemical kinetics are applied, the rates of the reactions responsible of food quality decay can be described as a function of food composition and of other external elements interacting with foods. Among them, water activity and water content have been widely used to determine the role of water in the kinetic reactions of deterioration. Recently, researchers have found limitations in using the water activity parameter. According to them, the role of water in foods can be better described by evaluating the role, in stability of the quality attributes, of the non-equilibrium states of amorphous food products. Following this approach, the dynamics of changes are described in kinetics terms and can be more efficiently predicted by the glass transition temperature more than by the water activity. The glass transition, which is a second order transition in amorphous materials from the glassy to the rubbery state, is primarily dependent on water, which is a plasticizer and is responsible for the physical state of multiphase systems (as foods are) together with temperature. The subject of the role of water in the decay of food quality is presented in this paper, according to the principles of food material science | L'impatto dell'acqua sulla termodinamica e sulla fisica dell'alimento e, quindi, sulla sua qualità è maggiore di quello di ogni altro componente chimico. Applicando principi fondamentali di cinetica chimica, le velocità delle reazioni responsabili del decadimento della qualità possono essere espresse in funzione della composizione e di fattori esterni al prodotto. L'attività dell'acqua o il contenuto in umidità sono stati ampiamente utilizzati per determinare il ruolo dell'acqua nelle reazioni cinetiche di degradazione. Scuole più recenti attribuiscono al concetto di attività dell'acqua alcune limitazioni: il ruolo dell'acqua negli alimenti è discusso in relazione allo stato di non-equilibrio dei prodotti alimentari amorfi nella stabilità degli attributi di qualità. Secondo questo approccio la dinamica dei cambiamenti è descritta in termini cinetici e può essere efficacemente predetta dalla temperatura di transizione vetrosa, più che dall'attività dell'acqua. La transizione vetrosa, transizione di secondo ordine da uno stato vetroso allo stato gommoso dei materiali amorfi, è innanzitutto influenzata dall'acqua quale plasticizzante del sistema, che, quindi, insieme alla temperatura, determina lo stato fisico delle fasi di sistemi multifase quali sono gli alimenti. Il tema del ruolo dell'acqua nel decadimento della qualità degli alimenti viene presentato in questo lavoro secondo i principi della scienza dei materiali alimentari
Mostrar más [+] Menos [-]The nexus of water-energy-food in China's tourism industry Texto completo
2021
Lee, Lien-Chieh | Wang, Yuan | Zuo, Jian
The tourism industry contributes significantly to the growth of the global economy and is considered to be strongly associated with a large amounts of water and energy consumption. In this study, the tourism water footprint (TWF) and the tourism energy footprint (TEF) of 138 sectors were investigated to examine the water-energy-food (W-E-F) nexus in the Chinese tourism industry from 2012 to 2017 by developing the water- and energy-based environmentally extended input-output analysis with the tourism satellite account. This study revealed that the W-E-F supply groups consumed total 15,556 million m³ of water and 4,964 million tce of energy to support the Chinese tourism industry. The largest contributor to the total TWF is the indirect water use from the food supply group (65%), while the largest proportion of total TEF is contributed by the direct energy use from 11 tourism direct sectors (63%), most especially the air transport sector. A much larger growth of the tourism industry was observed in 2017 compared to that of 2012. The structure decomposition analysis revealed that the growth of the overall water and energy consumption of China tourism is mainly driven by the growth of the total tourism expenditure, i.e. the scale effect. It is the same case for the food supply group associated with the Chinese tourism industry. In contrast, the contribution of the changes to the tourism expenditure composition is relatively low. Furthermore, the growth in water and energy consumption can be offset effectively by reducing the water and energy use coefficient and adjusting the economic production structure of tourism and its associated food supply group. In sum, the food supply and air transport sectors play a crucial role in the water-energy-food nexus of the tourism industry. Therefore, in the future, focus should be placed on improving the water and energy use efficiency of these sectors as well as enhancing their production structures.
Mostrar más [+] Menos [-]Fate of residues in soil - side effects on ground water, air and food
1992
Pawlizki, K.-H. (Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Muenchen (Germany). Abt. Pflanzenschutz) | Rinder, W.
The present review describes the processes occurring in the degradation of pesticides in soil and persues their entry to groundwater, air and food plants. To avoid groundwater pollution the adsorption and mineralization of pesticides in soil must be at least 99,98% of the soil-reaching substances. At lower retention rates groundwater protection is achieved only by minimizing the amount of application or by enlarging the intervals between the use of the same chemical ingredients
Mostrar más [+] Menos [-]New water-soluble chitin derivative with high antibacterial properties for potential application in active food coatings Texto completo
2021
Kritchenkov, Andreii S. | Kletskov, Alexey V. | Egorov, Anton R. | Tskhovrebov, Alexander G. | Kurliuk, Aleh V. | Zhaliazniak, Natallia V. | Shakola, Tatsiana V. | Khrustalev, Victor N.
The synthesis of new chitin derivatives through ultrasound-assisted treatment of the chitin with 1-azido-3-chloropropan-2-ol under Green Chemistry conditions is described. This is the first example of ultrasound-assisted polymer analogues transformation of chitin unaccompanied by noticeable backbone degradation or deacetylation. The obtained water-soluble azido chitin derivatives are characterized by high antibacterial activity, which is comparable with that of commercial antibiotics ampicillin and gentamicin. At the same time, they were demonstrated almost identical in vitro toxicity as unmodified chitin and chitosan. The antibacterial activity of the obtained polymers is mainly provided by azido moiety in their macromolecules. The conjugation of azido moiety to chitin backbone strongly diminishes the toxicity of the azido pharmacophore, but preserves its antibacterial properties. The most potent chitin derivative was used for the film coating of Ricotta cheese samples. This food coating proved to be efficient for the prolongation of shelf life of Ricotta cheese.
Mostrar más [+] Menos [-]Impacts of water and soil conservation strategies on households? food security in North West of Benin Texto completo
2014
b m nasser | k saidou | k a anderson | t rigobert | d a jonas | d fatondji | t moutouama fidele | e janvier | s nestor | a p b irenikatche | a perceval
This study aims at analyzing the impact of water and soil conservation strategies on households? food security in the North-western part of Benin. It was conducted in the municipalities of Boukombé and Ouaké. Three villages were studied. From random way, 180 producers were investigated. The causes of soil degradation, water and soil conservation strategies, available food supply and food consumption frequency were collected. Degradation factors were analyzed using discourse analysis and prioritized using the Friedman test. Food supply and frequency of consumption were compared between beneficiaries and non-beneficiaries of the projects using the Student t test. Land degradation is caused by socio-cultural factors (overexploitation of lands, trees? cutting, late bush fires, grazing, agroforestry and monoculture) and natural factors (heavy rains and steep gradient of the soils). The first three factors are respectively the exploitation of land, trees? cutting and late bush fires practice in both towns. Food reserves before the new crops were not affected by exogenous strategies released by the erosion control projects. But the frequency of food consumption is improved statistically among project beneficiaries than non-beneficiaries. This confirms the theory of Boserup | E Janvier et al., 'Impacts of water and soil conservation strategies on households? food security in North West of Benin', International Journal of Agricultural Science Research, vol. 3(10), pp.196-202, Academe Research Journals, 2014
Mostrar más [+] Menos [-]Impacts of water and soil conservation strategies on households' food security in North West of Benin Texto completo
2014
j egah
J Egah, 'Impacts of water and soil conservation strategies on households' food security in North West of Benin', International Journal of Agricultural Science Research, pp.196-202, 2014 | Th is study aims at analyzing the impact of water and soil conservatio n strategies on householdsâ?? food security in the North - western part of Benin. It was conducted in the municipalities of Boukombé and Ouaké. Three villages were studied. From random way, 180 producers were investigated. The causes of soil degradation, water and soil conservation strategies, available food supply and food consumption frequency were collected. Degradation factors were analyzed using discourse analysis and prioritized using the Friedman test. Food supply and frequency of consumption were compar ed between beneficiaries and non - beneficiaries of the projects using the Student t test. Land degradation is caused by socio - cultural factors (overexploitation of land s , trees â?? cutting , late bush fires, grazing, agroforestry and monoculture) and natural fa ctors (heavy rain s and steep gradient of the soils ). The first three factors are respectively the exploitation of land, trees â?? cutting and late bush fires practice in both towns. Food reserves before the new crops were not affected by exogenous strategies released by the erosion control projects. But the frequency of food consumption is improved statistically among project beneficiaries than non - beneficiaries. This confirms the theory of Boserup
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons : sources, fate and levels in air, water, soil, sediments, sludge and food in Ontario Texto completo
1992
Changes of the bacterial composition of goldfish [Carassius auratus] culture water during the decomposition of food pellets
1989
Sugita, H. (Nihon Univ., Tokyo (Japan). Coll. of Agriculture and Veterinary Medicine) | Arai, H. | Okada, S. | Nagaya, M. | Deguchi, Y.
Cold plasma for mitigating agrochemical and pesticide residue in food and water: Similarities with ozone and ultraviolet technologies Texto completo
2021
Gavahian, Mohsen | Sarangapani, Chaitanya | Misra, N.N.
Pesticide and agrochemical residues in food and water are among hazardous chemicals that are associated with adverse health effects. Consequently, technologies for pesticide abatement in food and water remain in focus. Cold plasma is an emerging decontamination technology, that is being increasingly explored for the abatement of agrochemical and pesticide residue in food and water. In some cases, rapid and complete degradation of pesticide residues has come to light. Such promising results encourage exploring scale-up and commercialization. To achieve this, unraveling mechanisms involved in plasma decontamination and the nature of degradation products is needed. The present review identifies the mechanisms involved in plasma- assisted removal of pesticide residues from food and water, draws parallels with mechanism of ozone and ultraviolet technologies, investigates the chemistry of the intermediates and degradates, and identifies some future research needs. The review recognizes that mechanisms involved in plasma processes have overlapping similarities to those identified for ozone and ultraviolet light, involving oxidation by hydroxyl radical and photo-oxidation. The toxicity of intermediates and degradates in plasma processing have not received much attention. The safety aspects of end products form plasma led degradation of pesticides should be considered for practical exploitation. Identification of intermediates and degradation products, recognition of most potent plasma species, understanding the influence of co-existing entities, the energy efficiency of plasma reactors, and the process economics deserve research focus.
Mostrar más [+] Menos [-]Quesungual slash mulch agroforestry systems (QSMAS): improving crop water productivity, food security and resource quality in the sub-humid tropics Texto completo
2015
j pavon | miguel angel ayarza | e. barrios | idupulapati m. rao | edgar amézquita collazos | oscar ferreira | l.a. welchez | a. castro | m.a. rondón | m rivera peña | e. garcía | d valladares
A. Castro et al., 'Quesungual slash mulch agroforestry systems (QSMAS): improving crop water productivity, food security and resource quality in the sub-humid tropics', Centro Internacional de Agricultura Tropical (CIAT), 2015
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