To investigate into the T-2 and HT-2 toxin occurrence, 240 samples of unprocessed cereals (maize, wheat, barley, and oats) were sampled from different fields located in three Croatian regions during ...2017-2018. In all samples, sum concentrations of T-2/HT-2 toxin were determined using the ELISA method, while the LC-MS/MS was used as a confirmatory method for both mycotoxins in positive samples (>LOD) and the establishment of T-2 over HT-2 toxin ratios. The results showed oats to be the most contaminated cereal, with T-2/HT-2 toxins detected in 70.0% of samples, followed by barley (40.9%), maize (26.8%) and wheat (19.2%), with the mean T-2/HT-2 ratio ranging from 1:2.7 in maize to 1:4.4 in oats. Sum T-2/HT-2 concentrations in two maize samples were higher than the indicative level recommended by the European Commission, necessitating subsequent investigations into the conditions under which these poorly investigated mycotoxins are produced. Statistically significantly (
< 0.05) higher concentrations of T-2/HT-2 toxin were determined in oats throughout study regions as compared to those found in wheat, but not maize and barley, while the concentrations of these mycotoxins were related to the regional weather in Croatia.
The bacterial species
is the most common causative agent of mastitis in cows in most countries with a dairy industry. The prevalence of infection caused by
ranges from 2% to more than 50%, and it ...causes 10-12% of all cases of clinical mastitis.
The objective was to analyze 237 strains of
isolated from the milk of cows with subclinical mastitis regarding the
,
and
genes and to perform
and multi-locus sequence typing (MLST).
Sequencing amplified gene sequences was conducted at Macrogen Europe. Ridom StaphType and BioNumerics software was used to analyze obtained sequences of
and seven housekeeping genes.
The
fragment was present in 204 (86.1%) of strains, while
and
gene were detected in 10 strains, and the
gene was not detected.
typing successfully analyzed 153 tested isolates (64.3%), confirming 53
types, four of which were new types. The most frequent
type was t2678 (14%). MLST typed 198 (83.5%) tested strains and defined 32 different allele profiles, of which three were new. The most frequent allele profile was ST133 (20.7%). Six groups (G) and 15 singletons were defined.
Taking the number of confirmed
types and sequence types (STs) into account, it can be concluded that the strains of
isolated from the milk of cows with subclinical mastitis form a heterogenous group. To check the possible zoonotic potential of isolates it would be necessary to test the persons and other livestock on the farms.
Honey is an important food supplement in the human diet because of its nutritional quality. Therefore, honey should be safe for human consumption. The purpose of this research was to evaluate ...physicochemical and microbiological properties of 64 honey samples. The physicochemical analysis (water content, hydroxymethylfurfural, electrical conductivity and diastase activity) showed that 95.31% of samples meet Croatian and European standards. Microbiological quality of tested samples was considered good with no pathogenic bacteria detected. In 34.38% of the samples, the yeast and mold count exceeded the limit established by legislation. The presence of yeasts was noted in 17 samples varying from 18 to 1300 CFU/g, whereas mold count ranged from 18 to 182 CFU/g. The study revealed that out of six genera of molds recovered, Cladosporium was the most frequent, followed by Alternaria, Penicillium, Mucor, Aureobasidium, and Stachybotrys. Considering that the majority of molds identified in this study are commonly found in bee hive environment and in digestive tract of honey bees, it can be concluded that the mold contamination of honey in this study derives mainly from primary sources. The presence of Stachybotrys sp. is an indicator of contamination that comes from secondary sources.
Practical applications
Due to continuous expansion of the world honey market and increasing awareness of consumers towards healthy food, the importance of quality control of honey has also grown. In respond to these demands, this study presents physicochemical and microbiological properties of different types of Croatian honey, with special emphasis laid on the identification of the present molds in incompatible samples. The results of this study provide useful data that Croatian honey has good level of quality and contribute to better understanding of the genera of molds present in the honey from this region.
U ovom istraživanju provedeno je ispitivanje kakvoće medova s područja Republike Hrvatske, uzorkovanih u razdoblju od 2019. do 2021. godine, kako bi se procijenila njihova kvaliteta i sukladnost ...prema zakonskoj regulativi. Analiza svih medova uključivala je fizikalno-kemijske pokazatelje vodu, električnu vodljivost, hidroksimetilfurfural, aktivnost dijastaze, slobodne kiseline, reducirajuće šećere, saharozu te melisopalinološku analizu. Rezultati su interpretirani u odnosu na kriterije propisane Pravilnikom o medu i Pravilnikom o kakvoći uniflornog meda. Ukupno je analizirano 84 uzorka meda, različitog botaničkog podrijetla (cvjetni, bagremov, kestenov, lipov, kaduljin, repičin, medljikovac) čijom je peludnom analizom utvrđeno kako njih 9 ne odgovara deklaraciji. Od fizikalno-kemijskih pokazatelja, hidroksimetilfurfural se pokazao kao najčešći uzrok nesukladnosti uzorka, s obzirom da je kod 13 medova koncentracija bila previsoka (>40 mg/kg). Osim što upućuje na pretjerano zagrijavanje i/ili neprikladno skladištenje meda, u nekoliko navrata izmjerena koncentracija hidroksimetilfurfurala je bila čak preko 100 mg/kg, što može ukazivati na patvorenje. U dva meda dobivena aktivnost dijastaze iznosila je 6, što je ispod propisane vrijednosti (8). Previsok udio saharoze zabilježen je kod jednog cvjetnog meda (6,99 g/100 g) i jednog repičinog meda (7,57 g/100 g), dok je kod dva kestenova meda i jednog kaduljinog razlog nesukladnog rezultata bila električna vodljivost. Sadržaj vode, reducirajućih šećera i slobodnih kiselina u svim pretraženim uzorcima bio je u skladu s propisanim. Najviše je uzorkovano cvjetnih medova (30) i bagremovih medova (30) pa je shodno tome i najviše nesukladnih medova pripadalo upravo tim vrstama, 8 odnosno, 9. Ukupno je zabilježeno 29 nesukladnih rezultata, što je rezultiralo s 22 uzorka meda koji nisu odgovarali kriterijima iz pravilnika, odnosno 26 % svih pretraženih uzoraka.
In this study, honey samples collected from througout Croatia in the period 2019-2021 were subjected to quality control in order to assess quality requirements regarding law regulation. Analysis of all honey samples included physico-chemical parameters moisture, electrical conductivity, hydroxymethylfurfural, diastase activity, free acidity, reducing sugars, sucrose and melissopalynology analysis. Interpretation of obtained results was made by comparison with the criteria of honey composition in the Ordinance on Honey and Regulation on the quality of unifloral honey, respectively. Pollen analysis performed on 84 honey samples with different botanical origin (floral, acacia, chestnut, lime tree, sage, rapeseed, honeydew) resulted with nine of them not being in accordance with their label. Regarding physico-chemical parameters, hydroxymethylfurfural proved to be the most common cause of sample noncompliance, since the measured concentration was too high (>40 mg/kg) in 13 of them. Although this indicates excessive heating and improper storage of honey, on several occasions measured concentration of hydroxymethylfurfural was above 100 mg/kg, which may be related to honey adulteration. In two honeys the obtained diastase activity was 6, which is below the prescribed value (8). Excessive sucrose content was recorded in one flower honey (6.99 g/100 g) and one rapeseed honey (7.57 g/100 g), while in two samples of chestnut honey and one sage honey the reason for the non-compliant result was electrical conductivity. All samples met the criteria for moisture content, reducing sugars and free acidity. Most of the collected samples were floral (30) and acacia honeys (30), so in accordance with that most of the non-compliant samples beloged to these two plant species, eight and nine respectively. In total, there were 29 non-compliant results which resulted with 22 honey samples that did not meet the Regulation criteria, and 26% of all analysed samples, respectively.
Postupci uzorkovanja za mikrobiološku analizu hrane mogu utjecati na krajnji rezultat mikrobiološke pretrage. Uzorkovanje trebaju provoditi educirane i stručne osobe; pribor i oprema za uzorkovanje ...moraju biti sterilni; uzorak koji se uzorkuje mora biti reprezentativan, što znači da mora predstavljati jednu seriju ili lot proizvoda iz koje je uzet. Vrlo je važno uzorkovati dostatnu količinu uzorka koja je dovoljna za mikrobiološku analizu. Transport uzoraka do laboratorija i početak pretrage mora se provesti u što kraćem vremenu uz poštivanje temperaturnog režima. Sa svim se uzorcima treba postupati tako da bi se izbjeglo bilo kakvo oštećenje ambalaže. Uzorci moraju biti propisno upakirani te pravilno označeni. Subjekt u poslovanju s hranom sam određuje učestalost uzorkovanja hrane, vode i površina koje dolaze u dodir s hranom koja je definirana
planom samokontrole, a nadležna tijela kontroliraju provedbu propisanih planova. Osim uzorkovanja tijekom samokontrole koje provode osobe u poslovanju s hranom u Republici Hrvatskoj postoje i službene kontrole koje su propisane od nadležnih tijela u Republici Hrvatskoj.
Mycotoxins may contaminate food of animal origin due to the carry-over effect and represent a potential risk to human health. The problem of Fusarium mycotoxin contamination becomes an issue ...especially during rainy years characterised by substantial temperature changes. The aim of this study was to investigate into the level of Fusarium mycotoxins zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in maize silage (n=21), concentrated dairy cattle feeds (n=56) and cow milk samples (n=105), taken during 2015 from households located in four Croatian regions. The presence of mycotoxins was determined using validated ELISA methods. A high level of feedstuffs’ contamination was evidenced, especially with ZEN, with values higher than recommended observed in 9.5 % of maize silage samples. Fourteen point three percent (14.3 %) of milk samples were DON positive, with the toxin concentrations ranging from 5.4 to 67.3 μg/L. ZEN was determined in 94.3 % of milk samples, ranging from 0.3 to 88.6 μg/L. FUM were not detected in any of the analysed milk samples. Given the tolerable daily intakes (TDIs) defined for these mycotoxins, human health risks arising from the consumption of cow milk can generally be considered low, even in times characterised by weather conditions that facilitate the production of Fusarium mycotoxins in cereals subsequently used as dairy cattle feed. The exception represents particular milk samples in which high ZEN concentrations were found.
The physiological properties of 47 Staphylococcus aureus strains were investigated. The test strains were grown on bacteriological media and identified by the ID32 STAF system for biochemical ...identification of bacteria. Sensitivity to antimicrobial agents was performed by the disc diffusion method. The nuc gene and the virulence factors coa, hla, hlb, hld, hlg, hlg-2, tst, eta, etb, lukF-PV and lukS-PV and mecA gene were detected by the polymerase chain reaction. Furthermore, the spa type of the studied isolates was also set. According to the obtained results, all strains had the nuc, coa, hla and hld gene. Ten strains (21.3 %) had also the tst gene, while 37 strains (78.7 %) had the hlg gene and 35 strains (74.5 %) had the hlb and hlg-2 genes. All of the investigated S. aureus isolates were penicillin resistant (100 %), with 29 strains which were also resistant to oxacillin (61.7 %). Methicillin (oxacillin) resistance was detected by the mecA gene detection, which is also the first MRSA result from the secretion samples of cows’ mammary glands in Croatia. The researched MRSA strains proved to belong to different spa types, and the most common were spa types t005, t011 and t521, and a new spa type t9498 was detected.
Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEN) often contaminate cereals and cereal by-products. Certain thermal processing methods used in the food industry show promising results in ...terms of reduction of cereal contamination with mycotoxins. In order to establish the degree of DON and ZEN reduction in naturally contaminated cereals (maize, wheat and oat), this study investigated the effects of cooking, roasting and extrusion cooking, performed at different temperatures (100 – 220 °C) and for a different length of time (10 – 30 min) on these mycotoxins concentrations. Before and after the treatment, cereal samples were analysed for DON and ZEN concentrations using enzyme-linked immunosorbent assay (ELISA). In comparison to cooking, which achieved only a negligible mean mycotoxin reduction (of up to 8% for DON and 11% for ZEN), roasting and extrusion cooking resulted in a significantly more pronounced mycotoxin reduction (of up to 40% for DON & 46% for ZEN and of up to 75% for DON & 80% for ZEN, respectively) (p < 0.05). The results show similar effects of thermal processing on all of the studied cereals (p > 0.05), suggesting that extrusion cooking can be considered as an effective thermal method capable of reducing mycotoxin content in cereals.
Various factors, such as weather and production practices (e.g., environmental hygiene, process duration, raw material quality, ripening temperature, and relative humidity), in combination with the ...intrinsic product properties (e.g., pH, aw, salt content), significantly affect the growth of surface moulds. The aim of this study was to isolate and identify surface moulds retrieved from traditional meat products (TMPs) and correlate these data to the production region and production technology. The surface of 250 TMPs (dry-fermented sausages, n = 108; dry-cured meat products, n = 142) from five Croatian regions were sampled during a two-year period. Dry-fermented sausages had a significantly higher pH and a lower salt concentration when compared to dry-cured meat products. In total, 528 isolates were obtained, comprising 20 Penicillium and 17 Aspergillus species. The species most frequently isolated from the dry-fermented sausages were P. commune (32.4 %), A. proliferans (33 %), and P. solitum (14.8 %), while A. proliferans (52.1 %), P. commune (28.9 %) and P. citrinum (19.7 %) predominated in dry-cured meat products. Aspergillus predominated on the TMPs from southern Croatia, while Penicillium was prevalent on products from the other four regions, possibly due to differences in weather conditions. Seven potentially mycotoxigenic species (A. creber, A. flavus, A. niger, A. westerdijkiae, P. citrinum, P. commune, and P. nordicum) were isolated and identified. Regular monitoring of mould species and their toxigenic metabolites present on traditional meat products is of the utmost importance from the public health perspective, while the results of such a monitoring can prove beneficial for the tailoring of the production technology development.
•Surface moulds on TMP depends on the environmental parameters and the production in households.•Penicillium species were predominant in continental and Aspergillus species in the coastal region.•The number of isolates on dry-cured meat products depends on the length of the ripening period.•50 % of the isolated mycotoxigenic species possess genes for mycotoxin production.
This study of incidence of deoxynivalenol (DON) and zearalenone (ZEA) was performed on the maize (Zea mays) harvested in Croatia after a growth period characterized with extremely high rainfall and ...low temperatures. A total of 40 maize samples were collected during harvesting in October 2010 at different maize fields located in the north, central and eastern part of Croatia. Determination of DON and ZEA concentrations was done by simultaneous use of two methods, ELISA/TLC and ELISA/HPLC, for DON and ZEA, respectively. The DON was detected in 85% samples with the maximum concentration of 17.92 mg/kg, while ZEA was detected in 87.5% samples with the maximum concentration of 5.11 mg/kg. Detected high concentrations of DON and ZEA in our research could be explained with the high humidity and significantly low temperatures in the period of growth that might have lead to increased contamination of maize with Fusarium moulds and production of its secondary metabolites.
► Study of incidence of DON and ZEA was performed on the maize harvested in Croatia. ► Determination was done by simultaneous use of ELISA/TLC and ELISA/HPLC method. ► DON was detected in 85% while ZEA in 87.5% samples. ► Results pointed to high contamination of maize. ► It might be consequence of high humidity and low temperatures during maize growth.
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