Spouted Bed and Jet Impingement Fluidization in Food Industry

Spouted bed and jet impingement fluidization are the cases of classic fluidization modification obtained by proper distribution of the fluid and the construction of device. The condition for the realization of both fluidization types is strict determination of the apparatus dimensions and process parameters. The chapter presents the issues concerning the choice of optimal operating conditions and dimensions of working elements of devices for both spouted bed and jet impingement fluidization, as well as possibilities for analysis of heat transfer in the process. Furthermore, the examples of industrial application of spouted bed fluidization and jet impingement fluidization in food technology are presented

Modeli određivanja vremena potrebnog za odmrzavanje hrane ovisno o uvjetima prerade i karakteristikama gotovog proizvoda

Determining thawing times of frozen foods is a challenging problem as the thermophysical properties of the product change during thawing. A number of calculation models and solutions have been developed. The proposed solutions range from relatively simple analytical equations based on a number of assumptions to a group of empirical approaches that sometimes require complex calculations. In this paper analytical, empirical and graphical models are presented and critically reviewed. The conditions of solution, limitations and possible applications of the models are discussed. The graphical and semi-graphical models are derived from numerical methods. Using the numerical methods is not always possible as running calculations takes time, whereas the specialized software and equipment are not always cheap. For these reasons, the application of analytical-empirical models is more useful for engineering. It is demonstrated that there is no simple, accurate and feasible analytical method for thawing time prediction. Consequently, simplified methods are needed for thawing time estimation of agricultural and food products. The review reveals the need for further improvement of the existing solutions or development of new ones that will enable accurate determination of thawing time within a wide range of practical conditions of heat transfer during processing.Toplinska i fizikalna svojstva proizvoda mijenjaju se tijekom odmrzavanja, pa je određivanje vremena odmrzavanja oduvijek predstavljalo problem. Razvijeni su različiti matematički modeli za rješavanje tog problema, počevši od relativno jednostavnih analitičkih funkcija koje polaze od niza pretpostavki, pa sve do raznih empirijskih modela što uključuju složene izračune. U ovom su radu kritički prikazani analitički, empirijski i grafički modeli. Osim toga, raspravlja se o uvjetima potrebnim za rješavanje problema, ograničenju i mogućoj primjeni modela. Grafički i polugrafički modeli izvedeni su iz numeričkih metoda. Numeričke metode nisu uvijek primjenjive jer izračuni oduzimaju puno vremena, a specijalizirani su programi i oprema uglavnom skupi. Zbog toga su za primjenu u inženjerstvu prikladniji analitičko-empirijski modeli. Ovaj revijalni prikaz potvrđuje da ne postoji jednostavna, točna i u praksi lako izvediva analitička metoda određivanja vremena odmrzavanja prehrambenih proizvoda, te da treba razviti jednostavnije metode. Zaključeno je da postojeća rješenja treba poboljšati ili treba razviti nove modele koji će omogućiti precizno određivanje vremena odmrzavanja u različitim uvjetima prijenosa topline prilikom obrade hrane

Review of thawing time prediction models depending on process conditions and product characteristics

Determining thawing times of frozen foods is a challenging problem as the thermophysical properties of the product change during thawing. A number of calculation models and solutions have been developed. The proposed solutions range from relatively simple analytical equations based on a number of assumptions to a group of empirical approaches that sometimes require complex calculations. In this paper analytical, empirical and graphical models are presented and critically reviewed. The conditions of solution, limitations and possible applications of the models are discussed. The graphical and semi-graphical models are derived from numerical methods. Using the numerical methods is not always possible as running calculations takes time, whereas the specialized soft ware and equipment are not always cheap. For these reasons, the application of analytical-empirical models is more useful for engineering. It is demonstrated that there is no simple, accurate and feasible analytical method for thawing time prediction. Consequently, simplified methods are needed for thawing time estimation of agricultural and food products. The review reveals the need for further improvement of the existing solutions or development of new ones that will enable accurate determination of thawing time within a wide range of practical conditions of heat transfer during processing

Microstructure and properties of YSZ coatings prepared by plasma spray physical vapor deposition for biomedical application

This paper presents the study of microstructure and properties of 8 mol% yttrium stabilized zirconia coating fabricated by Plasma Spray Physical Vapor Deposition technique on commercial pure titanium. The coating was characterized by X-ray diffraction, high resolution scanning electron microscope, profilometer, nanoindentation and nanomachining tests. The X-ray phase analysis exhibit the tetragonal Zr0.935Y0.065O1.968, TiO and α-Ti phases. The Rietveld refinement technique were indicated the changes of crystal structure of the produced coatings. The characteristic structure of columns were observed in High Resolutions Scanning Electron Microscopy. Moreover, the obtained coating had various development of surfaces, thickness was equal to 3.1(1) μm and roughness 0.40(7) μm. Furthermore, the production coatings did not show microcracks, delamination and crumbing. The performed experiment encourages carried out us to tests for osseointegration

Application of Metal Nanoparticles for Production of Self-Sterilizing Coatings

Metal nanoparticles (NPs) are increasingly being used in many areas, e.g., industry, pharmacy, and biomedical engineering. NPs can be obtained through chemical and biological synthesis or using physical methods. AgNPs, AuNPs, CuNPs, FeNPs, MgNPs, SnO2NPs, TiO2NPs, and ZnONPs are the most commonly synthesized metal nanoparticles. Many of them have anti-microbial properties and documented activity supported by many tests against some species of pathogenic bacteria, viruses, and fungi. AgNPs, which are used for the production of commercial self-sterilizing packages, are one of the best-explored nanoparticles. Moreover, the EFSA has approved the use of small doses of silver nanoparticles (0.05 mg Ag·kg−1) to food products. Recent studies have shown that metal NPs can be used for the production of coatings to prevent the spread of the SARS-CoV-2 virus, which has caused the global pandemic. Some nanoparticles (e.g., ZnONPs and MgONPs) have the Generally Recognized As Safe (GRAS) status, i.e., they are considered safe for consumption and can be used for the production of edible coatings, protecting food against spoilage. Promising results have been obtained in research on the use of more than one type of nanometals, which prevents the development of pathogen resistance through various mechanisms of inactivation thereof

Application of Iron Nanoparticle-Based Materials in the Food Industry

Due to their different properties compared to other materials, nanoparticles of iron and iron oxides are increasingly used in the food industry. Food technologists have especially paid attention to their ease of separation by magnetic fields and biocompatibility. Unfortunately, the consumption of increasing amounts of nanoparticles has raised concerns about their biotoxicity. Hence, knowledge about the applicability of iron nanoparticle-based materials in the food industry is needed not only among scientists, but also among all individuals who are involved in food production. The first part of this article describes typical methods of obtaining iron nanoparticles using chemical synthesis and so-called green chemistry. The second part of this article describes the use of iron nanoparticles and iron nanoparticle-based materials for active packaging, including the ability to eliminate oxygen and antimicrobial activity. Then, the possibilities of using the magnetic properties of iron nano-oxides for enzyme immobilization, food analysis, protein purification and mycotoxin and histamine removal from food are described. Other described applications of materials based on iron nanoparticles are the production of artificial enzymes, process control, food fortification and preserving food in a supercooled state. The third part of the article analyzes the biocompatibility of iron nanoparticles, their impact on the human body and the safety of their use

Analysis of Transport Conditions for Frozen Food on the Way from the Shop to Home

The transport of temperature sensitive products takes place under special conditions defined by specific agreements and international standards. The only exception to this rule is consumer transport. This transport is carried out by the consumer and takes place on the way home from the shop. The study examined consumers' awareness of the consumer transport of frozen food and analysed this type of transport in terms of the continuity of the cold chain. Such situation affects the deterioration of frozen food quality especially in case of its later storage in the home freezer. It was found that the average distance that customers cover from shop to home was 4.98 km. They usually used a car and covered this distance in an average of 12.85 minutes. During the summer months, this time is sufficient to partially thaw a package of frozen vegetables. Only 33% of the respondents used insulated bags to protect frozen food on the way home. When analysing the transport of frozen raw material carried out by consumers in real conditions, the use of insulated bags was found to be justified. These bags are able to keep the temperature of the packed raw material below −5°C. It was found that the legal imposition of the necessity to use such bags or the introduction by the manufacturer of frozen food of appropriate packaging protecting the food against transport at inappropriate temperatures in the summer months is necessary

Transakcje ponadprogowe w biurach rachunkowych a instytucja czynnego żalu. Zarys problematyki

The Act of 1 March 1 2018 on counteracting money laundering and terrorist financing states that certain obliged institutions, in particular entrepreneurs providing accounting services, are to inform the General Inspector of Financial Information about the deposits or withdrawals of funds with an equivalent value of more than 15,000 Euro. Despite publicly available information in this regard, these entrepreneurs remain in state of acute uncertainty concerning the correct interpretation of the obligation referred to in Article 72.1 of the cited law. As a consequence of the often incorrect interpretation of the provision, they apply to the supervisory authority to include their behaviour in the category of the institution of active repentance. This article attempts to make a balanced interpretation of Article 72.1 of the Act on counteracting money laundering and terrorist financing regarding the possibility of an entrepreneur invoking the institution of active repentance.Ustawa z dnia 1 marca 2018 roku o przeciwdziałaniu praniu pieniędzy oraz finansowaniu terroryzmu obliguje niektóre instytucje obowiązane, w szczególności przedsiębiorców prowadzących działalność w zakresie usługowego prowadzenia ksiąg rachunkowych, do informowania Generalnego Inspektora Informacji Finansowej o przyjętej wpłacie lub dokonanej wypłacie środków pieniężnych o równowartości przekraczającej 15 tys. euro. Pomimo ogólnodostępnej informacji w tym zakresie przedsiębiorcy ci nadal pozostają w pewnej postępującej niepewności w zakresie prawidłowej interpretacji obowiązku, o którym mowa w art. 72 ust. 1 przywołanej ustawy. W następstwie często błędnej interpretacji przepisu występują z wnioskami do organu nadzorczego o ujęcie ich zachowań w kategorii instytucji czynnego żalu. Niniejszy artykuł jest próbą dokonania zrównoważonej interpretacji art. 72 ust. 1 przywołanej ustawy w powiązaniu z możliwością powoływania się przez przedsiębiorcę na instytucję czynnego żalu

Subsidies versus economics, finances and income of farms (2)

The paper aimed at ex-post analysis of impact of subsides on the economic situation of farms, with special emphasis on the impact of environmental payments and compensatory payments (the so-called LFA payments). Chapters: Changes to the economic and production situation of farms implementing the agri-environmental scheme in Poland. Economic condition of beneficiaries of compensatory aid in less-favoured areas (the so-called LFA). Impact of changes to direct payment system in 2014-2017 on support for selected types of farms. Value management and assessment of the financial situation of family farms in Poland – selected aspects. Subsidies versus finances and economics of farms owned by natural persons

Modified gelatine structures as packaging material for frozen agricultural products

Gelatine gels modified by hydrated paper pulp (PP), ground extruded starch (ES) and hydrogel balls (HGB) were formed so that after the crosslinking process, the plates of suitable thickness could be obtained. Then the material was freeze-dried and the obtained porous gelatine structures as well as styrofoam (XPS) as the reference material were tested for thermal conductivity and bending. The temperature fields were examined during the thawing process of products placed inside the test packagings with modified gelatine structures and polystyrene as well as temperature field profile on outer surface of these packs. The studied materials resemble styrofoam in terms of thermal insulation and exhibited medium thermal conductivity ranging between 0.047 and 0.081 [W·(mK)-1]. The bending strength of the materials under investigation proved higher than that of styrofoam and this fact supports their applicability as an alternative for frozen agricultural products packages