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The prospects of sparkling wine production by the 'Champenoise' method using alginate-immobilised yeast cells were examined. Grape varieties dominant in quantity were selected within the group of recommended and permitted varieties of Kutjevo vineyards, located in the eastern part of continental Croatia. Research revealed that there are no influential variations in the principal physicochemical and sensory characteristics between sparkling wines obtained through immobilised yeast and traditional sparkling method. The analysis of aroma compounds showed minor differences between samples. Observed oenological parameters assessed in the final products did not show any relevant oenological differences, with the exception of alcohol content, which was slightly higher in sparkling wines made with yeast cells immobilised with calcium alginate beads. According to this research, the sensory properties of the produced sparkling wines, compared to sparkling wine produced with free yeast, did not show any significant differences. On the full-scale obtained results indicate that some of the selected varieties can be sorted as suitable for the production of sparkling wine using immobilised yeast cells.

Washing and blanching are two important steps for the processing of fresh good grade small shiitake into casual snacks and prepared foods. This study explored their effects on the dimensions, weights, proximate compositions, taste and bioactive compounds of the shiitake caps and stipes. Results showed that the dimensions and weights of the caps and stipes increased after washing but decreased after blanching. On a dry basis, washing did not affect the nutrients and bioactive compounds contents of shiitake except sugars and polyols compared to fresh samples. However, blanching greatly reduced all the quality contents of the shiitake. The major minerals in the caps and stipes were potassium, magnesium and calcium. The main polyol, sugar, free amino acid, and 5'-nucleotide of shiitake were mannitol, trehalose, glutamine and 5'-adenosine monophosphate, respectively. Equivalent umami concentration (EUC) in the caps was three-fold higher than that in the stipes. Ergosterol, ergothioneine, γ-aminobutyric acid (GABA), and total phenols contents in the caps were significantly higher than those of the stipes, but the polysaccharides showed the reversed. Overall, both caps and stipes contain the necessary nutrients and bioactive compounds, and the blanching significantly affected the above-mentioned components of all tested samples.

The correlations between water state and the key factors affecting sourdough quality, including cell activity and acidification capacity of lactic acid bacteria (LAB), were established in this study. Results revealed that with the increase of frozen storage time, the cell density (CD), total titratable acidity (TTA), and organic acids content declined, whereas the pH value rose. Further, the freezable water content (FWC) and free water quantity (FWQ) decreased, but the total water loss rate (WLR) and immobilised water quantity (IWQ) increased. The CD showed a highly inversely correlation with WLR, and the pH value was strongly inversely correlated to the FWQ. The confocal laser scanning microscopy (CLSM) observed that the ice crystals had larger volumes during frozen storage. Our data, for the first time, disclosed that the total water content and the FWQ may play a crucial role in maintaining the viability and acidification capacity of LAB in frozen sourdough.

Two varieties of palm date seeds (PDS), Sukkari and Khalas, were examined for their antioxidant and antibacterial activities. Total phenol content was 2 014.37 ± 212.05 and 2 060.40 ± 176.0 mg GAE 100 g-1 dry weight (DW); and total flavonoid content was 83.98 ± 1.10 and 94.97 ± 1.36 mg QE 100 g-1 DW for Sukkari and Khalas, respectively. PDS extracts showed potential scavenging activity against ABTS, DDPH, and hydroxyl radical; the calculated IC50s were 431.17 ± 12.45, 400 ± 10.87 and 680 ± 18.12 µg for Sukkari, and 476 ± 20.25, 302.24 ± 14.08 and 284.18 ± 11.62 µg for Khalas, respectively. PDS extracts did not show potential activity against superoxide anion. Both extracts showed a high percentage of reducing power as the calculated FRAP (ferric reducing antioxidant power) concentrations were 12.66 ± 1.08 and 16.14 ± 1.94 mmol ascorbic acid equivalent 100 g-1 for Sukkari and Khalas, respectively. Bacillus subtilis showed a remarkable sensitivity to PDS extracts; the inhibition zones were 21 ± 0.82 and 22 ± 0.67 mm for Sukkari and Khalas, respectively. PDS extracts possess good antioxidant and antibacterial activity, and therefore PDS could be effectively used as a natural source of antioxidants and to be detected against gram-positive bacteria.

Common bean (Phaseolus vulgaris L.) is one of the most important grain legume foods for the human diet. Common bean seed is gaining attention due to its content of secondary metabolites with positive effects on human health. The present work analysed the effect of common bean germination on the essential amino acid profile, active compound content, and expansion index after extrusion processing. The content of tryptophan (Trp) in raw common bean (RCB) and in germinated common bean (GCB) seeds was 6.1 and 7.9 mg·g^–1 of protein, respectively. The limiting amino acids in RCB were sulphur amino acids and Trp, and in GCB only the sulphur amino acids were the limiting amino acids. The germination process in beans increases the levels of quercetin and kaempferol and allows the synthesis of daidzein and genistein, and significantly increases the expansion index after extrusion processing. The germination of common bean could be used as a strategy to improve nutritional, nutraceutical, and processing properties.

The objective of this study was to quantify the concentration of acrylamide in biscuits, bread, and cake obtained from industrial and local bakeries, classified based on their colour intensity as light, medium, or dark. The analysis was performed using gas chromatography-mass spectrometry (GC-MS). Sugar, moisture, and asparagine analyses were also carried out simultaneously. The results demonstrated that the acrylamide content in biscuits, bread, and cakes varied according to the colour (light 109.9 ± 7.95, 214.7 ± 27.40, and 128.6 ± 7.05; medium 176.3 ± 15.16, 387.0 ± 87.71, and 804.3 ± 17.16; and dark 407.6 ± 105.13, 555.8 ± 16.20, and 1 015.0 ± 83.68 µg·kg^–1, respectively). Statistically, significant differences were observed between acrylamide content and product colour density (P < 0.05). It can be concluded that the acrylamide content increases as the product colour intensity rises due to the increased baking temperature at which the reaction between reducing sugars and asparagine takes place, resulting in the formation of acrylamide. The results suggest that selecting commercial bakery products based on colour may be beneficial for reducing the daily intake of acrylamide by consumers. Therefore, it is recommended to avoid dark-coloured bakery products.

Hazelnut is a product with high nutritional and economic value. In maintaining the quality value of hazelnut, the classification process is of great importance. In the present day, the quality classification of hazelnuts and other crops is performed in general manually, and so it is difficult and costly. Performing this classification with modern agricultural techniques is much more important in terms of quality. This study was based on a model intended to detect hazelnut quality. The model is about the establishment of an artificial intelligence-based classification system that can detect the hidden defects of hazelnuts. In the developed model, the visuals used in the dataset are divided into training and test groups. In the model, hazelnuts are divided into 5 classes according to their quality using AlexNet architecture and modern deep learning (DL) techniques instead of traditional hazelnut classification methods. In this model developed based on artificial intelligence, a very good approach was presented with the accurate classification of 99%. Moreover, the values regarding precision and recall were also determined at 98.7% and 99.6%, respectively. This study is important in terms of becoming widespread information technology use and computer-assisted applications in the agricultural economics field such as product classification, quality, and control.

The aim of the paper is to identify the factors influencing consumers when beer consumption and when choosing restaurants for beer consumption in the Czech Republic (CR). A partial goal was to compare preferences and factors influencing beer consumers from the Vysočina Region and the South-Moravian Region. The survey included a questionnaire survey, which 408 respondents took part in. The results showed that the most influential factors in the selection of beer for consumers are taste, a high-quality brand, and Czech production. Surprisingly, price was not found to be an influential factor in beer selection but is rather neutral. Factors that influence consumers most when choosing a restaurant for beer consumption were also identified. Consumers are most influenced by the quality of the beer on offer and the environment in which it is consumed.

We examine the nutritional effect of selected non-traditional grain samples added into wheat flour. In a form of flour, amaranth, quinoa, lupine, 5 hemp types, 2 teff types and 2 chia types were used for wheat flour substitution on a low and high level. Samples with amaranth and lupine flour showed the best improvement in terms of protein content (in the range between 21.1 and 26.0%). The highest total dietary fibre was found in lupine composites (7.1 and 9.8%). Hemp samples contained a significant amount of minerals in comparison with the control wheat sample (from 1.16% to 1.98%). According to the above-mentioned differences, flour composites containing single tested grains were distinguished by principal component analysis. All examined plant materials could be recommended for wheat flour fortification in terms of nutritional improvement. The addition of non-traditional flours partially changed both the volume and shape of laboratory prepared bread correspondingly to the type and added amount.

Pesticide residues and heavy metals were analysed in both fresh tender coconut water (FTCW) (n = 161) and packaged tender coconut water (PTCW) (n = 126) samples collected from three southern states of India [Andhra Pradesh (AP), Kerala (KL), and Tamil Nadu (TN)]. A method validated in the laboratory using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for pesticide residues, while heavy metals were analysed using a validated method of inductively coupled plasma-optical emission spectrometry (ICP-OES). Significant differences in heavy metal concentrations were assessed using analysis of variance (ANOVA) and post hoc test (between different varieties collected 'within' and 'among' states). FTCW samples [n = 9 (6%)] collected from TN showed Monocrotophos and Malathion residues in the range of 1.0 µg L^-1 to 51.6 µg L^-1 and 0.5 µg L^-1 to 0.6 µg L^-1, respectively, while they were detected in n = 5 (4%) of the PTCW samples at a range of 0.90 µg L^-1 and 0.82 µg L^-1 to 1.56 µg L^-1. Heavy metals such as cadmium (Cd), chromium (Cr), lead (Pb), and stannum (Sn) were detected in different varieties collected from all three states. Some of the PTCW samples also contained traces of Cd, Cr, cobalt (Co), and Pb. Arsenic (As) was found in one sample from KL, while none of the samples was contaminated with mercury (Hg). The present study accentuates the need for fixing standards for the pesticide residues in coconut water.

Acetyl-coenzyme A (CoA) is a key metabolite produced by the acetyl-CoA synthetase (ACS) gene in energy metabolism and biosynthetic pathways. ACS is speculated to be the branching site of monacolin K (MK) and citrinin production and related to the metabolite production of Monascus. In this study, the ACS expression was inhibited by ribonucleic acid interference (RNAi). T7 was selected for a follow-up analysis of the lowest ACS expression, which was 0.401 times higher than that of the wild-type strain. The effects on the colony morphology of Monascus were determined. The morphological characteristics of mycelia and spores were observed under a scanning electron microscope. The contents of secondary metabolites, namely, MK and citrinin, were determined through high performance liquid chromatography (HPLC). Colour values were measured with a spectrophotometer. Results showed that the low ACS expression could inhibit the growth of Monascus colonies and the hypha and affect the formation and morphology of Monascus M1 spores. It could also inhibit the production of the main secondary metabolites, namely, MK, citrinin, and pigment.

Coeliac disease is an autoimmune gluten-sensitive entheropathy. The only available treatment for it is the life-long adherence to a gluten-free diet although these products are often poor in proteins, minerals, and vitamins. The current study was designed to investigate the effect of buckwheat flour incorporation to a gluten-free experimental formulation on the size-related parameters, and microelements and proteins contents. Buckwheat flour affected positively the technological quality of bread, like bread specific volume index and loaf size. Increasing concentration of buckwheat flour (10-40%) in bread affected the proportional enrichment in proteins and microelements, especially in copper and manganese.

One of the efforts to produce functional foods is using ingredients containing health-beneficial bioactive compounds. Another way to produce functional foods is fermentation generating bioactive compounds or fortification with the bioactive compound extract. An ingredient historically believed to have benefits on health is moringa (Moringa oleifera) leaf powder. Moringa leaf powder is a valuable source of functional ingredients, including protein, vitamins, minerals, and phytonutrients such as carotenoids, tocopherols, polyphenols, flavonoids, alkaloids, and tannins. However, moringa is a plant that is distributed in various tropical countries in the world. Its quality depends on geographical differences, cultivars, environmental conditions, seasons, genotypes, and varieties. This article reviews the bioactive compounds of moringa leaf powder and the characteristics of moringa leaf powder extract. The effect of moringa leaf powder fortification on food product characteristics is also discussed. Moringa leaf powder possesses many pharmacological properties, such as anticancer, anti-inflammatory, hepatoprotective, cardioprotective, and antioxidant ones. The bioactivity of leaf extract is extracting solvent dependent. Therefore, fortification results in nutritional improvement and increasing health benefits of food products. However, the adverse effect is found in sensory. Thus properties, thus the moringa leaf powder fortification level usually is less than 10%. Changes in the functional properties of foods due to moringa leaf powder fortification have been studied to a limited extent. A low level of fortification might not affect the properties of food products. Therefore, moringa leaf powder is potentially used as a functional food ingredient. Some studies reported the toxicological effects of moringa leaf powder and the use of this ingredient, should be below the harmful doses.

The effect of different solvents and extraction methods on total anthoc yanins, phenolic compounds, and antioxidant capacity from x´kijit (renealmia alpinia Rottb. Maas) peels was evaluated. In order to evaluate the effect of solvents on the bioactive compounds extraction efficienc y and antioxidant capacity, a special cubic mixture design model was implemented with ethanol, methanol, and acetone as solvents and conventional (agitation - 1 and 6 h; Soxhlet - 2 and 4 h), novel (power ultrasound - 2.5 and 5 min) methods, and combination of extraction methods. Acceptable correla - tions between predicted and experimental data were obtained for total anthoc yanins ( r2 = 0.95), phenolic compounds (r2 = 0.78), and antioxidant capacity (r2 = 0.97), with methanol exhibiting the highest extraction yield of bioactive compounds and resultant antioxidant capacity. Although the extraction of total anthocyanins (82.2-85.8 mg cyanidine/ kg) and phenolic compounds (183.6-207.0 mg GAE/kg) was best carried out through Soxhlet, the ultrasonic treat- ment showed similar antioxidant capacity values (27.4-34.3 mg Trolox/kg) to those of 2-h Soxhlet. Moreover, a 5-min ultrasound pretreatment significantly increased (p < 0.05) phenolic compounds by 11, 21 and 12% when combined with agitation 1, 6, and 2-h Soxhlet treatments, respectively ; while the antioxidant capacity increased by 26, 48, and 22% for the same treatments. Ultrasound might be used as a valuable, green alternative procedure for improving the solvent extraction of bioactive compounds.

The effect of modified atmosphere packaging (MAP) in combination with cold storage on physicochemical and microbiological changes of farmed pufferfish was studied during 14 days of storage. Results showed that samples with MAP3 (gas composition of 60% CO₂, 5% O₂, 35% N₂) treatment had the significantly lower total volatile basic nitrogen, K value, and total viable counts. The water holding capacity, low field NMR analysis and MRI indicated that MAP3 was more effective in maintaining the water content and water migration. Analyses of free amino acids (FAAs) also indicated that MAP3 treatment had a positive effect on preventing the degradation of proteins and retained better flavour quality.

Phenolic compounds are linked to a number of health benefits, including antioxidant, antibacterial, antiglycaemic, antiviral, anticarcinogenic, anti-inflammatory and vasodilatory properties. To improve a great loss of phenolics during extrusion, researchers have investigated incorporating functional ingredients into the extrusion input mixture. Other reasons for the addition of active ingredients are the re-use of by-products from food technology, decreasing the calorie content of extruded food, inhibition of starch digestion, and the colour change of the gluten-free products. The paper presents 28 examples of new designs for extrusion based on rice, corn, cassava, sorghum, and lentil flours and on other crops, together with the analyses of phenolics. The present results show the highest total phenolic content in sorghum among cereals, and lentil flour and orange peel powder among mixtures for extrusion to prepare extrudates. The highest content of total flavonols was found in the mixture containing corn and freeze-dried red and purple potatoes.

The perceptions of individuals with coeliac disease about gluten-free products and their consumer behaviour when eating out in hospitality establishments in the Czech Republic were investigated. The dependence of the selected characters important in the consumer behaviour of coeliac patients in the decision-making process when choosing a dining establishment, in particular the focus on identifying the key criteria that influence the decision-making of coeliac patients when selecting a particular public catering establishment, were examined. 441 questionnaires were analysed. The result is a finding of the consistency and relevance of characters in the decision-making process of coeliacs when selecting dining establishments and their satisfaction with the range of gluten-free foods in open and closed dining establishments in the Czech Republic. Deglutenised foods (raw ingredients) are very expensive and a structured and economically balanced range of processed products should be found in the hospitality industry with the acceptance of the purchasing power of their consumers.

Eight types of capsules containing Bifidobacterium animalis subsp. lactis Bb12 with addition of inulin and/or ascorbic acid were prepared by emulsion method with milk protein matrix or by extrusion method with alginate matrix. The size of protein and alginate capsules containing only Bb12 was 204 ± 18 µm and 1.7 ± 0.1 mm, respectively. Addition of both inulin (1% w/w) and ascorbic acid (0.5% w/w) increased the size of alginate capsules. Both methods of encapsulation prevented efficiently the manifestation of Bb12 cell metabolic activity. All types of encapsulation provided higher resistance of Bb12 cells to the conditions of a model gastrointestinal tract (GIT) compared to free cells. The influence of co-encapsulation with inulin (1% w/w) and ascorbic acid (0.5% w/w) on viability in model GIT was not demonstrable in alginate capsules but it was significant in protein capsules. The most efficient was co-encapsulation in a protein matrix with 1% w/w inulin and 0.5% w/w ascorbic acid.

Until now, the relationship between the fat and oil composition and their oxidation stability has been studied only at elevated temperatures (typically above 100 °C). Therefore, the initial oxidation rates of 19 edible fats and oils were determined as an increase in the peroxide value during storage in the dark at 35 °C with free access to air (oxygen). The initial oxidation rates of fats and oils were compared with parameters characterising these fats and oils (peroxide value, acid value, fatty acid composition, antioxidant capacity, and tocochromanol content). Using a simple correlation analysis, the initial oxidation rate correlated the most strongly with the peroxide value of the analysed fats and oils (P < 0.01). A highly reliable model (P < 0.0001) was obtained by multivariate statistical analysis. According to this model, the initial oxidation rate is affected mainly by the peroxide value and then by total trans fatty acid content, and antioxidant capacity.

Disulphide bonds and sulphhydryl concentrations were evaluated to determine the effects on rheological, thermodynamic, pasting, and dynamic rheological characteristics of mixed flours. Gluten samples, first treated with sodium sulphite of different concentrations, were added into flour at a 4% level, which had a significant impact on free sulphhydryl, disulphide bonds, and the ratio of the two indices. There was no relevance between the ratio and other parameters except for free sulphhydryl. The mixed flour doughs had reduced water absorption, dough development time, dough stability time as well as degree of weakening (P < 0.05). Disulphide bonds were associated negatively with the rate of starch gelatinisation (C3-C2), peak, and setback and these characteristics were correlated strongly with dough development time, dough stability time, and progressive protein weakening (C2-C1). The stability of starch gelatinisation and cooking stability of mixed flours did not remain significantly different. The larger the concentration of sodium sulphite, the higher the peak, breakdown, final viscosity, and setback values, but there were no significant differences between samples. For all samples, storage modulus and loss modulus increased with increasing scanning frequency. For mixed doughs, the trend lines of moduli decreased with increasing levels of reduction in added gluten. There was no substantial effect on thermal properties of flours.

Grape juice of Cabernet Sauvignon was fermented with three axenic cultures of Saccharomyces cerevisiae (CS-V1, CS-V2, CS-V3) to determine the effect of yeast strain on the aroma of rosé wine. An analytical methodology based on headspace solid phase microextraction combined with comprehensive two-dimensional gas chromatography and high-resolution time-of-flight mass spectrometry was used for identification of volatile organic compounds (VOC) in resulting wines. This method allowed the identification of 97 VOC responsible for wine aroma which was strictly affected by the strain used for fermentation. Results of the statistical analysis showed that strains CS-V2 and CS-V3 had the highest similarity of VOC profiles while CS-V1 was significantly different. Wine fermented with yeast strain CS-V1 was characterized by a high concentration of hexyl octanoate, 2-phenylethyl octanoate and free terpenoids (farnesol, farnesyl acetate). Strain CS-V2 contributed to an increased relative concentration of 1-hexadecanol, 1-heptanol, 9-decenoic acid and nerolidol. Wine fermented with CS-V3 had a high level of benzaldehyde, hexyl hexanoate, benzeneacetaldehyde and terpenoids α-terpineol and nerol.

Fungal food spoilage is a common problem that leads to both great economic losses and serious health problems. This study screened the antifungal activity of 137 Lactobacillus plantarum isolates against six common food spoilage indicator fungi using an overlay method and indicator strains of the species Aspergillus flavus, Fusarium moniliforme, Penicillium expansum, Penicillium chrysogenum, Cladosporium cladosporioides, and Aspergillus niger. Among Lactobacillus plantarum isolates, strain IMAU80174 was selected as the most effective based on the results of mycelium growth inhibition by its cell-free supernatant (CFS) and tolerance to simulated gastrointestinal juices and bile. The CFS of Lactobacillus plantarum IMAU80174 showed heat and protease resistance, and it was active only in a low pH environment. The application of the CFS to golden-red apples could slow down spoilage caused by inoculation of Penicillium expansum.

A farewell to Associate Professor Jiří Čmolík

The microbiological and hygienic quality of cow's, goat's and sheep's milk in the Czech Republic was evaluated. Milk (230 samples) was collected on 41 farms and investigated from May 2012 to October 2014. Milk was analysed for the presence of selected groups and types of bacteria: mesophilic microorganisms (total plate count - TPC), enterococci, Enterobacteriaceae, Escherichia coli, Staphylococcus aureus, Salmonella spp., Campylobacter spp., and Listeria monocytogenes. Besides these indicators and pathogenic agents, somatic cell count was determined as one of the indicators of mammary gland health in cows. TPC ranged between 8.3 × 10² and 1.2 × 10⁹ CFU/ml and somatic cells between 1.6 × 10⁴ and 6.8 × 10⁶ cells/ml. The presence of E. coli was confirmed in 86.3% of samples and the colony counts ranged from 1.0 × 10¹ to 4.0 × 10⁶ CFU/ml. The presence of verotoxigenic E. coli was confirmed in 3 samples (1.3%) (cow's milk 0%; goat's milk 6.3%; sheep's milk 4.4%). The presence of S. aureus was confirmed in 29.1% of the samples (cow's milk 26.9%; goat's milk 34.4%; sheep's milk 39.1%), but the numbers were very low (< 5.0 × 10² CFU/ml). L. monocytogenes was confirmed in 3 examined samples (1.3%) (cow's milk 0.6%; goat's milk 3.1%; sheep's milk 4.4%). Salmonella spp. and Campylobacter spp. were not detected in any of the samples tested.

The series of phenolic acid (2-, 3-, 4-monohydroxy- and 2,4-, 2,5-dihydroxy) alkyl esters (methyl, ethyl, propyl, and butyl) were prepared, and their antimicrobial activities were determined. The antimicrobial activity against the tested microorganisms Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis was investigated and expressed by minimum inhibitory concentration (MIC) in the range of 1.2-20 mM. The inhibitory activity of higher esters of phenolic acids was found to be higher than that of methyl esters and acids. The minimum inhibitory concentration (MIC) of tested compounds was compared with that of 4-hydroxybenzoic acid and its esters (parabens).

The purpose of the present work was to investigate the impact of somatic cell count (SCC) on the content of milk casein and to compare the sensitivity of different methods for the determination of the casein level in milk. Two different methods were employed in order to determine the casein level: routine method - infrared spectrophotometry and reference method - Kjeldahl. Data array of 26, 169 milk samples of the livestock control was used to analyse milk casein variation by SCC limits. Mean casein values (investigated by the routine method) varied from 2.47% to 2.8% (2.65 ± 0.09) and casein number (in % on crude protein basis) - CN% varied from 79.5% to 81.1%. The present analysis showed that the relation between SCC and casein content obtained by the routine method correlated significantly (Pearson correlation r_p = 0.644, P < 0.05, R² = 0.414, Spearman correlation r_s = 0.786, P < 0.05). Evaluated results obtained by the least squares method, and linear approximation of variation indicators presented a noticeable decline in casein percentage - 0.27%, when SCC increased by 80 × 10³/ml, but only when the studies were done by the reference method.

The study aimed to demonstrate how irradiation affects the chemical composition and amino acids of Spunta potato flour, and the sensory evaluation of biscuit samples partially composed of irradiated potato flour. The potato flour was irradiated with 50 and 150 Gy. Protein, fat, total dietary fibre, ash, carbohydrates, ascorbic acid, and amino acids were analysed. Sensory evaluation of biscuits was conducted after adding potato flour as a partial replacement for wheat flour at ratios of 5, 10, and 15%. The results showed that potato flour contained ascorbic acid, which was absent in wheat flour. Potato flour had less total protein and carbohydrate and more ash and fibres than wheat flour. Total essential amino acids appeared at the highest percentage, particularly lysine at 8.29 ± 0.02, compared with non-essential amino acids in the samples irradiated at a dose of 150 Gy. The biscuits were prepared with different ratios of the irradiated potato flour at dose 150 Gy to white flour. Sensory evaluation for biscuits with 10% of potato flour scored 8.61 ± 0.01, 8.33 ± 0.02, 8.77 ± 0.02, and 8.38 ± 0.00 for overall acceptance, colour, texture and appearance, respectively. This study recommends using 10% of irradiated potato flour at 150 Gy blended with wheat flour to produce biscuits.

The subject of this study was to investigate lactic acid bacteria (LAB) and yeasts microbiota of traditional sourdough (n = 36) and to indicate characteristics of enriched sourdough that is produced from combinations of isolates. A total of 60 LAB and 40 yeasts were identified from sourdough by matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry (MALDI-TOF MS) analysis. The dominant LAB microflora was Lactobacillus brevis (43.33%), Pediococcus acidilactici (21.67%) and Lactobacillus plantarum (18.33%). The dominant yeasts microflora was Saccharomyces cerevisiae (27.5%), Pichia kudriavzevii (25.0%) and Kluyveromyces marxianus (12.5%). The sourdough prepared with the combination of L. brevis, Leuconostoc mesenteroides, P. acidilactici and S. cerevisiae, K. marxianus showed the best physicochemical and microbiological properties while that with L. plantarum, L. brevis and P. kudriavzevii, Wickerhamomyces anumalus was the poorest. LAB and yeasts in the sourdoughs were ranged from 6.58 log CFU g^-1 to 9.12 log CFU g^-1 and from 6.12 log CFU g^-1 to 7.88 log CFU g^-1, respectively. Various chemical parameters such as pH, total titratable acidity (TTA), ethanol, and sourdough volume were differ depending on the type of microbial species. TTA was more pronounced in the sourdoughs produced with homofermentative LAB. Yeasts and LAB were dominated during continuous enriching of sourdough, supporting an important role during fermentation.

Since the adherence to the gluten-free diet in celiac patients affects the consumption from the grain food group, questions have been raised about the effects of such diet on calcium, iron, and fiber intake, as well as total carbohydrate and grain food consumption. Therefore, in the framework of this research, eleven types of nutritionally valuable gluten-free raw materials were proposed for consumption in gluten-free diet. They were investigated considering their macronutritive composition, different starch classes, the contents of essential minerals, dietary fiber, and polyphenols, as well as their antioxidant activity. The results were compared to the values obtained with wheat flour that was used as the reference raw material indicating that, in many aspects, the gluten-free raw materials mentioned can be considered as nutritionally more valuable in comparison to wheat flour. Especially satisfying results were obtained regarding the contents of proteins, dietary fiber, polyphenols, iron, and calcium. Therefore, the raw materials investigated can be recommended as desirable components that may contribute to the diversity, functionality, and nutritional quality of gluten-free diet.