Cultural heritage items are composed mainly of organic compounds which are susceptible to biodegradation. Various molds species are the most widespread biological agents that cause damage to library ...materials. Molds that can produce cellulose enzymatic complex, which degrades and damages cellulose, are most dangerous to paper, because cellulose is its main component. Mold spores are constantly present in the air, in the dust and on various objects, and in the favourable conditions the molds will easily develop. The degree of paper susceptibility to mold attack depends on the chemical characteristics of the paper and the environmental conditions in the library. Critical environmental factors, which are favorable for mold growth on paper, are presence of mold spores, source of nutrients, sufficient moisture, appropriate temperature for certain species of mold and limited air circulation. The most important condition for germination of mold spores is moisture. Good hygienic measures and elimination of environmental conditions that can cause mold growth are the best means of prevention of mold attacks. Infected materials have to be isolated, cleaned and disinfected by specified procedures. The most common genera of molds on paper are Chaetomium, Trichoderma, Aspergillus, Penicillium, Stemphylium, Alternaria, Stachybotrys and Cladosporium. The 47 mold species that are most frequently isolated from paper are systematized in this study.
Kulturna baština većinom se sastoji od organskih tvari koje su podložne biodegradaciji. Među biološkim uzročnicima oštećenja materijala knjižnične građe najrasprostranjenije su različite vrste ...plijesni. Najopasnije plijesni za papir su one koje imaju sposobnost proizvodnje celulaznog enzimskog kompleksa, koji razgrađuje i oštećuje celulozu, glavni sastojak papira. Spore plijesni stalno su prisutne u zraku, u prašini i na predmetima, i u povoljnim uvjetima iz njih će se razviti plijesan. Stupanj podložnosti papira napadu plijesni ovisi o kemijskim svojstvima papira i fizičkim uvjetima u knjižnici. Kritični čimbenici okoliša pogodni za rast i razvoj plijesni na papiru su prisutnost spora plijesni, izvor hranjivih tvari, dovoljna količina vlage, odgovarajuća temperatura za određenu vrstu plijesni i ograničeno strujanje zraka. Najvažniji uvjet koji plijesni trebaju za klijanje spora je vlaga. Najbolji način za prevenciju napada plijesni su higijenske mjere i uklanjanje uvjeta koji bi mogli omogućiti njihov razvoj. Zaraženu građu potrebno je izolirati i određenim postupcima očistiti i dezinficirati.
Rodovi plijesni koji se najčešće nalaze na papiru su Chaetomium, Trichoderma, Aspergillus, Penicillium, Stemphylium, Alternaria, Stachybotrys i Cladosporium.
U ovom radu sistematizirano je 47 vrsta plijesni koje su najčešće izolirane s papira.
Honey is usually adulterated by cheaper, commercially available sugar syrups with similar chemical composition. Adulterated honeys are frequently marked as natural and are valued in the same way as ...pure honeys and as a result, there is a growing need for rapid, simple, and accurate analytical methods to evaluate their characteristics and authenticity. In this work potential of UV-VIS and NIR spectroscopy coupled with PLS modelling and ANN modelling was analysed for the detection of adulteration and quantification of the physical and chemical proprieties of pure and adulterated honey samples. Acacia honey samples from Krapina-Zagorje County (Croatia) were adulterated by corn syrup (10–90%). The results indicate that PLS models developed in this work, except that for moisture content, can be used efficiently for screening (7<RER<20). ANN modelling provided accurate and simultaneous prediction of the properties of honey with correlation coefficients for validation above 0.8 so that these results show significant performance of ANNs modelling in the prediction of the physical and chemical properties of pure honey samples and adulterations based on combined UV-VIS NIR spectra.
•Acacia honey samples from Krapina-Zagorje County (Croatia) adulterated by corn syrup.•Detection of adulteration based in UV-VIS and NIR spectra.•PLS and ANN models for prediction of the physical and chemical properties of samples.•PLS efficient for samples screening.•ANN simulation precise prediction of the physical and chemical properties of samples.
Honey adulteration with cheap sweeteners such as corn syrup or invert syrup results in honey of lesser quality that can harm the objectives of both manufacturers and consumers. Therefore, there is a ...growing interest for the development of a fast and simple method for adulteration detection. In this work, near-infrared spectroscopy (NIR) was used for the detection of honey adulteration and changes in the physical and chemical properties of the prepared adulterations. Fifteen (15) acacia honey samples were adulterated with glucose syrup in a range from 10% to 90%. Raw and pre-processed NIR spectra of pure honey samples and prepared adulterations were subjected to Principal Component Analysis (PCA), Partial Least Squares (PLS) regression, and Artificial Neural Network (ANN) modeling. The results showed that PCA ensures distinct grouping of samples in pure honey samples, honey adulterations, and pure adulteration using NIR spectra after the Multiplicative Scatter Correction (MSC) method. Furthermore, PLS models developed for the prediction of the added adulterant amount, moisture content, and conductivity can be considered sufficient for screening based on RPD and RER values (1.7401 < RPD < 2.7601; 7.7128 < RER < 8.7157) (RPD of 2.7601; RER of 8.7157) and can be moderately used in practice. The R2validation of the developed ANN models was greater than 0.86 for all outputs examined. Based on the obtained results, it can be concluded that NIR coupled with ANN modeling can be considered an efficient tool for honey adulteration quantification.
The growing problem of food products adulteration requires a rapid and simple method for adulteration detection. Adulterants, which can range from plant material to natural and synthetic colours and ...compounds have a severe influence on customer trust as well as public health risks. Food safety regulations are being tightened and expanded, requiring a more thorough examination of hazards and risk management solutions. Due to its advantages, near infrared spectroscopy has been recognised as an effective method for food adulteration detection. In this work, an overview of the basics of NIR spectroscopy, NIR data analysis and the use of NIR for food adulteration detection are discussed.
