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An update of US food safety, food technology, GM food and water protection and management legislation Full text
2006
Arvanitoyannis, Ioannis | Tserkezou, Persefoni | Varzakas, Theodoros
US government was the first to introduce Hazard Analysis Critical Control Point, the system that had a tremendous impact on everybody's life starting from the food and packaging companies up to consumer themselves. The rest of the nations simply followed US approach with a considerable delay both in terms of legislation and implementation. In the case of genetically modified (GM) or genetically engineered foods, the situation was entirely different. United States benefited from the 'dubious', and definitely not proved, 'substantial equivalence' principle invoked as the most practical approach to assess the safety of GM foods and food ingredients. US legislation appeared to be considerably more lenient than the European Union. The latter required many more analyses and labelling of GM food or food components. In this article, an update is attempted of the entire US legislation falling in fields like food safety, food technology, GM foods and finally legislation referring to specific foods (animal origin - meat, poultry, fish, dairy; and agricultural produces - vegetables, fruits) and water quality by means of fourteen comprehensive tables.
Show more [+] Less [-]Water–water and water–macromolecule interactions in food dehydration and the effects of the pore structures of food on the energetics of the interactions Full text
2012
Wang, J. C. | Liapis, A.I.
A molecular dynamics (MD) modeling and simulations approach has been rationally built and developed to study porous food systems constructed with amylose and dextran chains. The findings from our MD studies indicate that the presence of food macromolecules decreases the energetics of the water–water interactions for the nearby water molecules in the pore space, but provides additional water–macromolecule interactions that can significantly outweigh the partial loss of water–water interactions to make the adjacent water molecules strongly bound to the food macromolecules so that the water activity and water removal rate are decreased as dehydration proceeds and, thus, the dehydration energy requirement would be increased. The effects of pore structures are greater in systems with higher densities of food macromolecules, smaller in size pores, and stronger water–macromolecule interactions. Dehydration of food materials can thus be reasonably expected to start from the largest pores and from the middle of the pores, and to have non-uniform water removal rates and non-planar water–vapor interfaces inside individual pores as well as across sections of the food materials. The food porous structures are found to have good pore connectivity for water molecules. As dehydration proceeds, water content and the support from water–water and water–macromolecule interactions both decrease, causing the food porous structures to adopt more compact conformations and their main body to decrease in size. Dehydration in general also reduces pore sizes and the number of pore openings, increases the water–macromolecule interactions, and leads to the reduction of the overall thermal conductivity of the system, so that more energy (heat), longer times, and/or greater temperature gradients are needed in order to further dehydrate the porous materials. Our thermodynamic analysis also shows that the average minimum entropy requirement for food dehydration is greater when the water–macromolecule interactions are stronger and the food macromolecular density is higher. The importance of the physicochemical affinity of food molecules for water and of the compatibility of the resultant porous structures with water configurational structures in determining food properties and food processing through the water–macromolecule interactions, is clearly and fundamentally verified by the results and discussion presented in this work.
Show more [+] Less [-]Water and Pathogenic Viruses Inactivation—Food Engineering Perspectives Full text
2020
Roos, Yrjö H.
Water is an essential component of food structures and biological materials. The importance of water as a parameter affecting virion stability and inactivation has been recognized across disciplinary areas. The large number of virus species, differences in spreading, likelihood of foodborne infections, unknown infective doses, and difficulties of infective virus quantification are often limiting experimental approaches to establish accurate data required for detailed understanding of virions’ stability and inactivation kinetics in various foods. Furthermore, non-foodborne viruses, as shown by the SARS-CoV-2 (Covid-19) pandemic, may spread within the food chain. Traditional food engineering benefits from kinetic data on effects of relative humidity (RH) and temperature on virion inactivation. The stability of enteric viruses, human norovirus (HuNoV), and hepatitis A (HAV) virions in food materials and their resistance against inactivation in traditional food processing and preservation is well recognized. It appears that temperature-dependence of virus inactivation is less affected by virus strains than differences in temperature and RH sensitivity of individual virus species. Pathogenic viruses are stable at low temperatures typical of food storage conditions. A significant change in activation energy above typical protein denaturation temperatures suggests a rapid inactivation of virions. Furthermore, virus inactivation mechanisms seem to vary according to temperature. Although little is known on the effects of water on virions’ resistance during food processing and storage, dehydration, low RH conditions, and freezing stabilize virions. Enveloped virions tend to have a high stability at low RH, but low temperature and high RH may also stabilize such virions on metal and other surfaces for several days. Food engineering has contributed to significant developments in stabilization of nutrients, flavors, and sensitive components in food materials which provides a knowledge base for development of technologies to inactivate virions in foods and environment. Novel food processing, particularly high pressure processing (HPP) and cold plasma technologies, seem to provide efficient means for virion inactivation and food quality retention prior to packaging or food preservation by traditional technologies.
Show more [+] Less [-]Food grade microemulsion systems: Canola oil/lecithin:n-propanol/water Full text
2016
Abbasi, Soleiman | Radi, Mohsen
In this study, the capability of a natural surfactant, lecithin, and the influence of ionic strength, pH, and temperature on some properties of a food grade microemulsion system were evaluated. For this purpose, the pseudoternary phase diagrams of canola oil/lecithin:n-propanol/water microemulsions in the presence of different salts (NaCl and CaCl2), ionic strengths, pHs, and temperatures were constructed. Our findings showed that the presence of salts slightly increased the W/O areas on the phase diagrams, whereas pH variation was not effective on the microemulsion formation. The expansion of microemulsion areas with temperature indicated the greater triglycerides solubilization capacity of lecithin based microemulsions at higher temperatures. These findings revealed the efficiency of lecithin-based microemulsion system for solubilization of triglycerides which can potentially be used for extraction of edible vegetable oils particularly canola oil.
Show more [+] Less [-]Effects of water on the physical properties of food Full text
2019
Kawai, K. (Hiroshima University, Higashi-Hiroshima, Hiroshima (Japan). Graduate School of Integrated Sciences for Life)
Solid food products are typically in an amorphous state, and their physical properties change dramatically at the glass to rubber transition temperature (Tsub(g)). Tsub(g) decreases with increasing water content because of water plasticizing effects. When Tsub(g) becomes lower than the ambient temperature, a glass to rubber transition occurs at the ambient temperature. The water content at Tsub(g) = 25℃ is usually described as the critical water content (w sub(c)). In this review, the effect of glass to rubber transition on the texture of cookies, the caking of mango powder and the compressibility of soup powder is explained. Tsub(g) of the food samples was evaluated by differential scanning calorimetry or thermal rheological analysis. Wsub(c) was determined from the relationship between Tsub(g) and water content. Fracture properties of the cookie samples changed from brittle to ductile at Wsub(c). Caking of mango powder occurred at water contents above Wsub(c). Hardness of soup powder compressed at temperatures above Tsub(g) was much higher than when compressed at temperatures below Tsub(g).
Show more [+] Less [-]Food quality for Daphnia in humic and clear water lakes Full text
2007
GUTSEIT, KELLY | BERGLUND, OLOF | GRANÉLI, WILHELM
1. Growth and reproduction of Daphnia fed lake seston were measured in two categories of meso- to eutrophic lakes differing with respect to terrestrial organic matter influence (humic and clear water lakes). The content of highly unsaturated fatty acids (HUFA), P and N, as well as the taxonomical composition of seston were analysed. 2. Seston HUFA and C : P ratios were similar between lake categories, whereas C : N ratios were lower in the clear water lakes in both spring and summer. Despite the similarity in HUFA and P content of seston, Daphnia growth rate, clutch size and the proportion of gravid females were, respectively, about 1.5, 3 and 6 times higher in the clear water lakes. 3. Differences in growth and reproduction were related to a combination of higher N content and good fatty acid quality of the seston in the clear water lakes. Relatively high biomass of edible algae, such as Rhodomonas sp. and Cryptomonas sp., in the clear water lakes, and differences in water pH likely contributed to the observed differences in Daphnia growth and reproduction between lake categories. Additionally, it is possible that Daphnia was energy limited in the humic lakes despite high particulate organic carbon (POC) concentrations, as the contribution of non-algal and detrital C to the POC pool was high. 4. Our results suggest that dietary HUFA content has the potential to improve herbivore growth and reproduction if N and P are not limiting. N merits more attention in studies of zooplankton nutrition.
Show more [+] Less [-]Use of Water Properties in Food Technology: A Global View Full text
2014
Kasaai, Mohammad R.
Water is a major component of drinking water, beverages, and most foodstuffs. In this study, an effort has been made to employ selected properties of water for: (1) evaluation of interactions of water with other food components; (2) discussion on the effects of water properties on food and beverage products; (3) applications of water properties in food technology; and (4) comparison of water properties with corresponding properties of similar substances. This study provides the following major conclusions: (i) unusual properties of water are mostly due to its high permanent dipole moment, partial ionic character of O–H covalent bonds, and extensive hydrogen bonds; (ii) different properties of many foodstuffs are strongly related to various properties of water; (iii) the properties of food products change depending on water availability and temperature; (iv) preparation of drinking water is a prerequisite for production of any safe drinks and foodstuffs; (v) water contributes important roles in quality, flavor, and shelf-life of foods; and (vi) water is used in food industries as a fluid for heat transfer; as a medium for temperature moderation in food processing; as a solvent for sugars, salts, water-soluble vitamins, and acids; as a dispersing agent for hydrophilic food components; as a dispersed phase for emulsified products; or as a reactant for several reactions in food processing.
Show more [+] Less [-]Water as the determinant of food engineering properties. A review
2004
Lewicki, P.P.
Water affects safety, stability, quality and physical properties of food. The influence of water on physical properties of food is dependent on the state of water in food. The state, expressed as water activity, is briefly discussed in the paper. Further, the influence of water on such physical properties as rheological, thermal, mass transfer, electrical, optical and acoustic is presented in details.
Show more [+] Less [-]Influence of water activity on food product quality and stability
1980
Although maximum stability of natural products has been tied to minimum total moisture, research in the last 25 years has defined a narrow optimum water activity range for many natural foods. Water activity has a closer relationship to the chemical, physical, and biological properties of foods than moisture content; it may have a direct effect on chemical and enzymatic reactions and on microorganism proliferation. Fairly narrow water activity ranges may cause changes in texture, color, flavor, aroma, stability, and acceptability of both processed and raw food products. Most applied work in this field has been pioneered by "water activists" who have used their own tools and methods. Preparation of moisture sorption isotherms will be facilitated by development of automatic, precise, rapid, and convenient techniques to determine water activity and absolute moisture content.
Show more [+] Less [-]Applications of electrolyzed water in the food industry: A comprehensive review of its effects on food texture Full text
2024
Samiye Adal | Berrak Delikanlı Kıyak | Gülşah Çalışkan Koç | Özge Süfer | Azime Özkan Karabacak | Nuray İnan Çınkır | Yasemin Çelebi | G. Jeevarathinam | Sarvesh Rustagi | R. Pandiselvam
This comprehensive work explores the multifaceted field of electrolyzed water (EW) and its crucial role in altering the textural characteristics of various food categories. The analysis begins by providing a clear explanation of EW and its different types, including slightly acidic (AC) EW, plasma-activated EW, neutralized EW, alkaline EW, and weakly ACEW. The review highlights the novelty of EW in preserving food quality, making it a significant alternative to various cleaning and disinfecting methods. The focus then shifts to the applications of EW, examining the impact of different EW types on the textural compositions of various food categories. The examination of the textural profile of foods, which is a crucial determinant of consumer preference, is comprehensively conducted across various categories, encompassing baked goods, meat and poultry, marine foods, fruits and vegetables, as well as ready-to-cook items like noodles. Furthermore, the review investigates the combined effects of EW, when utilized in conjunction with other technologies. The integration of EW with ultrasound, high-pressure processing, plasma activation, slurry ice, and other technologies, assessing their collective impact on textural attributes, was explored. As a consequence, this paper examines the present uses and impacts of electrolyzed water on the texture of food and also investigates its potential synergies with other technologies. The thorough analysis presented here establishes a basis for future research directions in this rapidly developing area, facilitating the exploration of inventive methods for food processing and preservation.
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