Heavy metals cause serious problems in the environment, and they can be accumulated in organisms, especially in the higher fungi. The concentration of Ni, Cr, Pb, Cd, and Hg in 10 species of edible ...mushrooms in Medvednica Nature Park, Croatia was therefore determined. In addition, the similarity between the studied species was determined by cluster analysis based on concentrations of the aforementioned metals in the fruiting bodies. The contents of nickel, chromium, lead, cadmium, and mercury in the fruiting bodies of mushrooms were obtained by X-ray fluorescence spectrometry. The highest concentrations of Ni (3.62 mg kg
−1
), Cr (3.01 mg kg
−1
), and Cd (2.67 mg kg
−1
) were determined in
Agaricus campestris
. The highest concentration of Pb (1.67 mg kg
−1
) was determined in
Macrolepiota procera
, and the highest concentration of Hg (2.39 mg kg
−1
) was determined in
Boletus edulis
. The concentration of all heavy metals significantly differed (
p
< 0.001) between examined saprophytic and ectomycorrhizal mushrooms. Considering anatomical part of the fruiting body (cap-stipe), a considerably higher concentration of the analyzed elements was found in the cap for all mushroom species. According to calculated bioconcentration factors, all the examined species were found to be bioexclusors of Ni, Cr, and Pb and bioaccumulators of Cd and Hg. Cluster analysis performed on the basis of the accumulation of the studied metals revealed great phenotypic similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation.
The aim of the study was monitoring of phthalic acid esters in agricultural soils of the Czech Republic over the period of 6 years, namely dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate ...(DEHP). Monitoring took place in twelve regions of the Czech Republic. Soil samples were taken evenly from the top and bottom soil horizons using a zig-zag pattern. Soil samples were taken from arable land, permanent grassland, and hop field. Lyophilisation of the samples was done by ultrasound-assisted extraction using a mixture acetone-hexane (1:1). Phthalic acid esters were analysed using high-performance liquid chromatography with UV detection. Subsequently, the results were statistically compared by analysing the principal components (PCA) to determine the effect of individual factors on the content of phthalic acid esters in agricultural soil. Factors such as precipitation, distance from a pollution source, amount of pesticides, and amount of artificial and organic fertilizers were taken into account. If we compare the concentrations established in this study with the limits set out in the Methodological Instruction of the Ministry of the Environment of the Czech Republic based on RSLs (Regional Screening Levels) issued by the USEPA (United States Environmental Protection Agency), none of these values were exceeded.
This study investigated the occurrence of 5 unregulated mycotoxins in a total of 250 traditional dry-cured meat products sampled in 2020 and 2021 in five Croatian regions (eastern, northern, central, ...western, and southern). Aflatoxin B1 (AFB1), ochratoxin A (OTA), sterigmatocystin (STC), citrinin (CIT), and cyclopiazonic acid (CPA) concentrations were related to the geographical region of the product’s origin and to local weather. The results revealed the contamination of 27% of samples, namely, STC in 4% of samples in concentrations of up to 3.93 µg/kg, OTA in 10% of samples in concentrations of up to 4.81 µg/kg, and CPA in 13% of samples in concentrations of up to 335.5 µg/kg. No AFB1 or CIT contamination was seen. Although no statistically significant differences in concentrations of individual mycotoxins across the production regions were found, differences in mycotoxin occurrence were revealed. The eastern and western regions, with moderate climate, delivered the largest number of contaminated samples, while the southern region, often compared with subtropics, delivered the smallest, so that the determined mycotoxins were probably mainly produced by the Penicillium rather than the Aspergillus species. Due to the interaction of various factors that may affect mycotoxin biosynthesis during production, the detected concentrations cannot be related solely to the weather.
The influence of the drying technique on certain quality attributes of dried grapes was analysed. Five varieties of grape were used in this study (Bezsemenné, Perlette, Vrboska, Beauty seedless, and ...Jakubské). All the varieties were dried using four methods: drying at 40 °C, combined drying (70, 65, and 60 °C), drying at 70 °C, and lyophilisation. The quality attributes such as total soluble solids, water activity, content of vitamin C, the colour parameters (L*, a*, b*), and microbiological (colony forming units, moulds, yeasts) and sensory (smoothness, gloss, colour, odour, chewability, juiciness, flavour, and overall impression) analysis were determined, depending on the method of drying. Lyophilised grapes from the Jakubské variety had the highest vitamin C content. They contained 0.58 mg of vitamin C per 100 g of dried grapes. However, no significant differences between varieties in vitamin C content were found. This confirmed concerns about the negative impact on the nutritional quality of dried grapes with increasing temperature. The lowest total count of microorganisms (CFU), moulds, and yeasts were determined after using highest drying temperature (70 °C). Higher CFU values were determined in lyophilised grapes, and then followed by grapes dried at 40 °C. Lyophilised grapes and grapes dried at 40 °C achieved the best sensory rating in general. The final product was intended to have a unique appearance while maintaining the evaluated quality parameters.
As fermentation is an integral feature of both, dry sausage and cheese production, this has led to the evaluation of bacterial cultures
ssp.
(LL8307) and
(ED0207) originally isolated from artisanal ...Croatian hard type cheese to diversify the range of flavours of dry fermented sausages and to increase their microbiological safety. Both strains were chosen for their high or medium acidifying, proteolytic and/or lipolytic activity and bioprotective potential after step-by-step selection of wild isolates. Therefore, this study aims to evaluate the survival rate of selected starter cultures in wild boar meat sausages during the ripening period of 40 days at a local small-scale facility under artisanal conditions as well as their influence on sausage quality parameters.
Safety, biotechnological and probiotic properties of twenty-three enterococcal and lactococcal isolates of dairy origin were studied. Based on the results, two best candidates were selected and added to the meat batter during the artisanal wild boar meat sausage preparation where their survival rate, effect on physicochemical, microbiological and sensorial properties and histamine content were evaluated.
As revealed by repetitive element-polymerase chain reaction (rep-PCR), native starter cultures survived up to 15 days of ripening and were either absent from (LL8307) or reduced by 80% (ED0207) in final products. The application of native starter cultures rapidly decreased pH (p<0.05), leading to the significantly lower load of
coliforms and
in ready-to-eat sausages prepared by the addition of starter cultures (3.04-3.94 log CFU/g) than in the control (3.88-5.00 log CFU/g). Analysis of hedonic test data revealed that some of the sensory traits (odour, flavour, juiciness) of treatments with starter cultures were highly liked by the higher percentage of consumers. The results suggest that these starter cultures would represent a valuable tool to improve the homogeneity of artisanal manufacture and hygienic quality of fermented sausages and can be safely used for food application.
This is the first study to explore in depth the biotechnological potential of bacterial cultures isolated from artisanal Croatian cheese as functional starter cultures for high-quality game meat sausage production.
Glutamate is one of the most abundant amino acids in nature, accounting for up to 8-10% of most dietary proteins and peptides and most tissues. Only the free form of glutamate has taste-enhancing ...properties as a unique umami taste, and when glutamate is bound to proteins, it is tasteless with no umami taste. Fermentation, ageing, ripening and heat cooking are typical natural processes of protein hydrolysis during which free glutamate is released. The food industry most commonly uses it in the form of monosodium glutamate (MSG) in amounts between 0.1 and 0.8% as a flavour enhancer. Since the beginning of the 21st century, its use as a flavour enhancer in meat and meat products with reduced salt content has become more widespread. The sodium content of MSG (12.28 g/100 g) is one-third that of salt (39.34 g/100 g), making MSG a promising salt alternative in sodium reduction strategies. There is no one-sided and conclusive scientific information reporting adverse human health effects of MSG in the general population, and it is still considered safe. However, in the wake of "clean label" initiatives, many consumers would prefer not to have additives or flavour enhancers such as glutamates in their food. This can be overcome by the known synergistic effect of natural 5'-ribonucleotides and glutamates found in seaweed, cheese, fish sauce, yeast extract, soy sauce, fermented soybeans and tomatoes, as they enhance the overall perception of umami flavour.
The aim of this study was to evaluate the effect of a supplementation diet for hens consisting of dried basil herb and flowers of calendula and dandelion for color, carotenoid content, iron-induced ...oxidative stability, and sensory properties of egg yolk compared with commercial pigment (control) and marigold flower. The plant parts were supplemented in diets at two levels: 1% and 3%. In response to dietary content, yolks from all diets differed in carotenoid profile (
< 0.001). The 3% supplementation level resulted in a similar total carotenoid content as the control (21.25 vs. 21.79 μg/g), but by 3-fold lower compared to the 3% marigold (66.95 μg/g). The tested plants did not achieve yolk color fan values as the control (13.47) or 3% marigold (11.47), and among them, calendula had the highest values (9.73). Despite the low carotenoid content in diets supplemented with basil herb, iron-induced malondialdehyde (MDA) concentration was low as for marigold (on average 106.83 vs. 92.68 ng/g after 250 min). The treatments differed in sensory color scores for fresh and hard-boiled yolks and flavor while other sensory properties were similar. In conclusion, the supplementation of plants in a hen diet may result in yolks containing carotenoids and other compounds showing a high antioxidant effect.
This research aimed to determine the meat production indicators and carcass traits of Posavska crested hen, which is the Croatian indigenous chicken breed. The research was carried out on five ...strains of the Posavska crested hen breed: yellow vetch, vetch, red colourful, light gray, and golden brown. Feeding was ad libitum for the whole time, adapted to the age of the chickens from a nutritional point of view. Separation by sex was carried out at the age of four weeks, while slaughter of roosters and determination of carcass traits was done at the age of 18 weeks. The highest average body weight was achieved by roosters of light gray and yellow vetch strain (3542.63 and 3430.38 g, respectively) and light gray pullets (2562 g) at the age of 18 weeks. The lowest feed conversion ratio was achieved by the light gray strain (2.39) at four weeks of age, and by the the roosters of the light gray strain (4.07) and pullets of the light gray and golden brown strain (4.08) at 18 weeks of age. The average dressing percentage was 71.54%, while the highest average dressing percentage was established in the red colourful strain (72.48%). Regarding the proportion of individual parts of the carcass, a significant (P < 0.05) influence of the strain can be seen in the proportion of drumsticks in the carcass, the proportion of which was the highest in the yellow vetch strain (18.69%). A significant influence of the strain was also found regarding L* (P < 0.01) and a* (P < 0.05) skin color indicators. Considering the established differences between the strains, it is necessary to carry out further selection and work on the uniformity of the breed.
The present study focused on the use of sewage sludge (SS) as a casing material amendment and the potential uptake of metal elements by the cultivated white button (
: MS-39) mushroom. Laboratory ...experiments were performed under controlled environmental conditions to grow
on the composted wheat straw substrate for 50 days. Different treatments (0, 50, 100, 150, and 200 g/kg) of casing material were prepared by mixing garden and dried SS and applied on the mushroom substrate after proper sterilization. The results revealed that SS application was significant (
< 0.05) in accelerating mushroom yield with a biological efficiency of 65.02% for the mixing rate of 200 g/kg. Moreover, the maximum bioaccumulation of selected metal elements (Cu, Cr, Cd, Fe, Mn, and Zn) was observed using the same treatment. Additionally, the multiple regression models constructed for the uptake prediction of metal elements showed an acceptable coefficient of determination (
> 0.9900), high model efficiency (ME > 0.98), and low root mean square error (RMSE < 0.410) values, respectively. The findings of this study represent sustainable use of SS for the formulation of mushroom casing material contributing toward synergistic agro-economy generation and waste management.
This study addresses the application of native, multiple strain starter cultures for standardization of game meat sausages production. The designed starter cultures consisting of two indigenous
...Lactobacillus sakei
and one
Leuconostoc mesenteroides
strains. These strains were used in both, the encapsulated and non-encapsulated form, in the game meat dough, individually or in combination, with eight treatments in total. Microbiological and physicochemical characteristics of the sausages were monitored throughout the manufacturing process, while sensory properties, biogenic amine content, and volatile compounds were evaluated in the final products. As revealed by rep-PCR, native starter cultures, encapsulated or non-encapsulated, had survived the whole sausage production process; however, to varying degrees. The application of indigenous decarboxylase negative
Lb. sakei
strains significantly (
P
< 0.05) reduced tyramine content, rapidly decreased pH and promoted the number reduction of
Enterobacteriaceae
and elimination of
E. coli
,
L. monocytogenes
and coliforms in ready-to-eat products. A total of 84 volatile compounds were identified by SPME–GC–MS in the eight treatment batches of game meat sausages, with only minor differences between the treatments. No significant differences in sensory traits (
P
> 0.05) between tested treatments were found, although treatment with the
Lb. sakei
strains received the highest scores for the sensory traits including cross-section, odour, hardness, aroma, and overall acceptability. Combination of multi-strain
Lb. sakei
starter cultures resulted in growth prevention of undesirable microbiota, reduction of tyramine content and increased the acceptability parameters of full-ripened sausages, which make them good candidates for industrial as well as artisanal application.