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The processing of chocolate bars is influenced by cocoa beans used. Chocolate bar is one of the downstream products with a simple processing process. The taste and aroma in candy comes from chocolate bars. Fermentation is an important activity in the formation of cocoa flavour. This study aims to determine the panellists' acceptance of chocolate bars produced from various fermentation treatments of sun-dried cocoa beans. The materials used in this study were cocoa beans of varieties of Lindak. The fermentation variation consisted of two treatments, namely, the addition of the inoculum gradually (A1) and the addition of the inoculum simultaneously at the beginning of fermentation (A2). The inocula added were Sacharomyces cerevisiae (FNCC 3056), Lactococcus lactis (FNC 0086) and Acetobacter aceti (FNCC 0016). The control treatment was dry cocoa beans without fermentation (A0). The fermentation time was 120 h, then the fermented cocoa beans were processed into chocolate bars. The resulting chocolate bars were subjected to sensory analysis including evaluation of the taste of sepia, bitter, and sour taste and in the test the polyphenol content of chocolate bars was used. The results showed that there was a decrease in the septic, bitter and sour taste from treatment A0, A2 and A1, respectively. The highest polyphenol content was in A0, A2, and A1, respectively. Panellists stated that the preferred chocolate bar was made from cocoa beans with A1 treatment.

The relationship between body weight and total mercury content in the muscle of common carp (Cyprinus carpio) from 13 uncontaminated ponds in South and West Bohemia was investigated. In total, 215 three-years-old marketable carps and 26 samples of bottom sediment were analysed. Total mercury contents (THg) in muscle and sediments were determined using an single-purpose atomic absorption spectrophotometer. The correlation between body weight and mercury content in muscle was found to be negative and statistically significant (Pearson correlation: r_p = -0.269, P < 0.001). THg content in muscle significantly decreased as the body weight of carp from uncontaminated ponds increased. This is likely due to the intensive weight gain of marketable carp.

Filamentous fungi were isolated from ten spices collected from markets in Indonesia. The aim was to enumerate fungal contamination and to determine the toxigenicity of Aspergillus flavus strains on each of the spices. Viable fungal populations were determined using a dilution method. Toxigenicity of Aspergillus flavus was determined by culture on a quick screening coconut agar and by PCR using four sets of primers specific for aflatoxin pathway genes. All the tested spices were contaminated by storage fungi, Species of Aspergillus was the most commonly isolated moulds followed by species of Fusarium, Mucor, Penicillium and Rhizopus. The greatest number of Aspergillus flavus isolates were found on white pepper, followed by nutmeg, cardamom, and black pepper. The greatest number of Aspergillus chevalieri isolates were found on coriander, followed by nutmeg. Fifty strains of A. flavus were isolated, all of the strains produced large sclerotia and biseriate conidiophores. Their toxigenicity was assayed by the presence of yellow pigment on a quick screening coconut agar medium and PCR amplification of regulatory and structural genes in the aflatoxin pathway.

Aiming to reduce the sodium content in saltine crackers, the present study employed a methodology of salt coating that provided an inhomogeneous distribution of salt so that the salt perception was not altered. To this end, three cracker recipes were prepared and compared. Recipe 1 (F1) was the standard, Recipe 2 (F2) had a 33.3% reduction in salt in the dough, and Recipe 3 (F3) had no salt in the dough but instead a salty coating with the same amount of salt as F2. Physicochemical and sensory analyses revealed that F1 and F3 were not statistically different in salt perception, whereas F2 differed from the others. From these results, it was concluded that the methodology of covering crackers with a salty coating with a 42.5% salt reduction could be an alternative to achieving salt reduction.

Citronellol and hydroxy citronellal are fragrance ingredients used in decorative cosmetics and fine fragrances. They have many applications in flavourings, extracts, foods, and drugs manufacturing. Their use worldwide is in the range exceeding 1000 metric tons per annum. Previous studies investigated the biotransformation of citral by the free cell method and immobilised cell method with Saccharomyces cerevisae. In this research, the microbial transformation of citral by the sporulated surface cultures method with Aspergillus niger-PTCC 5011 was studied. In experiments, A. niger was inoculated on solid media in conical flasks. The transformation took place for the periods of time of 6 days and 15 days. The results were analysed by the theoretical study, Fourier transform infrared spectroscopy, gas chromatography, and gas chromatography-mass spectroscopy. The major compounds produced in 6 days were acetone (26.2%) and hydroxy citronellal (37.0%), while the major compounds after the 15-day period were acetone (15.0%) and citronellol (36.0%). As citronellol has numerous commercial applications, the 15-day biotransformation period was found to be preferable.

The changes in the structure of cereal proteins during the mixing of flour into dough was described and evaluated. Wheat gliadins and glutenins (gluten proteins) have unique physical properties and play an important role in breadmaking. The effect of mixing time on the formation and the structure of the gluten network was determined using scanning electron microscopy (SEM). Buckwheat flour (gluten-free) was used to compare the development of structure during the mixing process.

The cells of commercial strain Bifidobacterium animalis subsp. lactis Bb12 were encapsulated using emulsion encapsulation in a milk protein matrix. The volume based median of the microcapsules was 52.1 ± 6.2 µm. The stability of free and encapsulated cells was compared during 28 day-storage in pineapple juice and in strawberry-apple juice at 8 ± 1°C and 22 ± 1°C. Encapsulation ensured a higher number of cells compared to the free cells only at 8 ± 1°C. Strawberry-apple juice was found to be not suitable as probiotic vehicle. Both free and encapsulated cells lost their viability after 14 days at 22 ± 1°C. The number of bifidobacteria cells, pH and lactic and acetic acid content did not change in pineapple and strawberry-apple juice after 24 h cultivation at 37°C.

The effects of different concentrations of thyme (group T), clove (group Cl), and rosemary (group R) extracts on the microbiological, chemical, and sensory attributes of fish patty made from the bonito fish (Sarda sarda Bloch, 1793) were investigated. The numbers of total mesophilic aerobic bacteria, coliform bacteria, Staphylococcus-Micrococcus spp. and yeasts and moulds in group R were lower than those of the other groups during storage (P < 0.05). During the storage period, total volatile basic nitrogen (TVB-N), thiobarbituric acid index (TBA-i), peroxide values, and free fatty acid content gradually increased in all groups, and significant differences were found between the groups (P < 0.05). The results of sensory evaluation showed that the shelf life of fish patties was 4 days for the control group, and 8, 10, and 14 days for the groups treated with thyme, clove and rosemary essential oil, respectively (P < 0.05). In conclusion, the addition of essential oils showed a positive effect on the product shelf-life; and in particular, rosemary essential oil produced a remarkable effect.

The microstructural, physical, and sensory properties of low-fat sauces made with different rice starches, soy protein ,and inulin were analysed in order to obtain sauces suitable for celiac and lactose intolerant consumers. Soy protein and inulin could prevent starch degradation due to their high water-binding capacity. Moreover, protein molecules could diffuse into the starch granules and soluble inulin could interact with starch polymers within the granule. Both effects would hinder amylose leaching. Inulin provides better diffusion capacity of gelatinised granules and soy protein-starch granule aggregates than sunflower oil, which helps to decrease viscosity in modified rice starch sauces. Soy protein prevents syneresis in the sauces. Inulin affects colour parameters in native rice starch sauces, probably because of inulin and retrograded amylose polymers interactions. Sauces made with sunflower oil and modified rice starch are best rated by consumers. However, according to the statistical analyses, the replacement of oil by inulin could be suitable to prepare low-fat, gluten, and lactose free white sauces when modified rice starch is used.

The effects of wheat flour replacement at different levels (5, 7.5, 10, and 20%) by celery root and sugar beet pulp powder on rheological parameters and quality properties of enriched pasta were studied. Sensory evaluation was also investigated. Incorporation of fibre powders increased water absorption and prolonged dough stability and dough development time. Enriched pasta had higher moisture content than control pasta. Addition of fibre powders also modified the cooking quality of pasta (cooking loss and water absorption were increased and optimal cooking time was reduced). Moreover cooked pasta with the higher addition level of celery root powder was characterised by higher intensity of vegetable taste and had pleasant flavour and colour. Sensory evaluation showed that pasta with the addition of 7.5% celery root powder was the most acceptable for assessors.

The colour, chemical composition, texture parameters, hydration properties and fatty acids profile of fresh wild boar meat and meat after 2 months of freezing were compared. The research material was the M. longissimus dorsi muscle cut out of wild boar carcasses (Sus crofa). Analyses of physical and chemical properties of samples taken from 16 boars were performed. Samples were packed and frozen to -18°C and stored under such conditions for a period of two months. Freezing storage significantly increased the elasticity value and the colour of the meat as indicated by the decrease in L* and b* values. In frozen meat there slightly increased thermal drip and forced drip. The changes in the fatty acid profile under the effect of freezing were found more often in fat from muscle M. longissimus dorsi than in back fat of wild boar. In conclusion, it should be noted that freezing storage in a short time does not affect negatively the quality of frozen meat.

The antioxidant activity of 17 Czech medicinal plants was studied and compared with the antioxidant activity of green tea. The antioxidant activities of water and ethanol extracts of the plants tested were determined by a spectrophotometric method using the stable free radical DPPH (2,2-diphenyl-1-picrylhydrazyl), and further the contents of the compounds with reducing properties in water extracts were determined by flow injection analysis with amperometric detection (using a detection potential +0.7 V). Considerable antioxidant activities were found in the extracts of plants from the Rosaceae family (rosehips and leaves of raspberry, blackberry, and strawberry), the Lamiaceae family (oregano, sweet balm, thyme, dead-nettle, and mint), and flowers of linden and elder.

The bioactive compounds, as well as the in vitro antioxidant activity of two Savoy cabbage cultivars, Dama and Leticia, grown in west of Spain under similar conditions were identified, quantified and compared. We found that cv. Dama presented in general betters results when compared with cv. Leticia. Cv. Dama presented higher concentrations of chlorophyll a (2.26 mg/100 g fresh weight), total phenolic content (102.71 mg of chlorogenic acid equivalent/100 g fresh weight) and total intact glucosinolates (195.22 µmol of sinigrin equivalent/100 g fresh weight). Thus, cv. Dama exhibited higher values of in vitro antioxidant activity.

Response surface methodology-central composite rotatable design (RSM-CCRD) was applied to explore the optimum media formulation for maximising canthaxanthin (CTX) biosynthesis by Dietzia natronolimnaea HS-1. The effects of three variables of enzymatically hydrolysed molasses (EHM) (16.6-33.4 g/l), sodium (Na)-citrate (21.64-28.36mM), and yeast extract (6.32-9.68 g/l) concentrations on the production of CTX, total carotenoid (TCT), and biomass dry weight (BDW) were appraised. The results showed that the quadratic effects of EHM, yeast extract, and Na-citrate contents in terms of second-order polynomial regression equations (R² = 0.968-0.986), respectively, had the most significant effects on the produced TCT and CTX. The predicted maximum accumulation of BDW (8.88 g/l), TCT (7.24 mg/l), and CTX (6.40 mg/l) under the optimum concentrations of the media variables (26.16 g/l EHM, 8.29 g/l yeast extract, and 25.86mM Na-citrate) was very close to the experimental values determined in batch experiments. The high BDW content suggested EHM and Na-citrate as very promising feedstocks for CTX bioproduction by the bacterium studied.

Historically, species of the family Lamiaceae have enjoyed a rich tradition of use for flavouring, food preservation, and medicinal purposes, due to both their curative and their preventive properties. It is well known that each species has a special, complex mixture of bioactive compounds in which each component contributes to its overall bioactivity. Their value lays in the production of a wide range of secondary metabolites with potent antibacterial, antioxidant, anti-inflammatory, antimicrobial, antiviral, and anticancer activities. This review focuses on the Lamiaceae species and their secondary metabolites encompassing a wide array of beneficial functions and their applicability as sources of functional foods. It could help in addressing specific consumer needs as healthy diet is a part of the lifestyle that maintains or improves overall health.

Peanut skins were isolated from deshelled and dried conventional and high-oleic peanuts. In order to obtain simpler mixtures of phenolics with other components of the respective extract, the samples were extracted with solvents of increasing polarity (hexane, ethyl acetate, and methanol). The amounts of extracts were as follows: methanol > hexane > ethyl acetate, and the contents of phenolic constituents in the extracts: ethyl acetate > methanol > hexane. Ethyl acetate extracts from the skins of both conventional and high-oleic peanuts were about the same. The amount of peanut skin ethyl acetate extract was higher than that of tea leaves, but lower than those of Labiatae plants which were also analysed. Antioxidant activities under the conditions of the Schaal Oven Test in lard and in rapeseed oil were only moderate, lower than in the case of synthetic antioxidants (butylated hydroxytoluene, butylated hydroxyanisole, ascorbyl palmitate). The reducing power, free DPP* radical scavenging, inactivation of hydroxylic, and superoxide free radicals were medium, comparable to those of synthetic antioxidants; these activities also resembled to those in the extracts of conventional and high-oleic peanut skins.

The effect of whey powder, whey protein concentrate, caseinomacropeptide, and malt addition into milk on the growth and acid production of lactobacilli (Lactobacillus casei Lafti L-26, Lactobacillus acidophilus CCDM 151, and Lactobacillus casei CCDM 198) was evaluated. The ability of these strains to use different types of saccharides from milk and plant sources was also tested. Glucose, galactose, fructose and maltose were utilised by all tested strains. The results showed that the addition of malt positively affected the growth of lactobacilli strains compared to the growth in milk enriched by whey ingredients. The addition of malt increased significantly the production of d(-)isomer of lactic acid by Lactobacillus acidophilus CCDM 151 and Lactobacillus casei CCDM 198 and the production of acetic acid by Lactobacillus casei CCDM 198.

White lupin seeds have been used in human nutrition and treatment for several thousand years. Nowadays the use of white lupin seeds is limited by a small scale of their production. However, in the last 20 years quite new properties of white lupin have been discovered for the application in the production of different kinds of functional food. Unique traits of protein, fatty acids with a desirable ratio of omega-6 to omega-3 acids, and fibre as well as other specific components, for example oligosaccharides and antioxidants or non-starch carbohydrates, make white lupin an excellent component in many healthy diets. The effects of white lupin components concern the physiological condition of the human body, including diabetes, hypertension, obesity, cardiovascular diseases, lipid concentration, glycaemia, appetite, insulin resistance, and colorectal cancer. Seeds are used among others for the production of gluten-free flour, bacterial and fungal fermented products, noodle and pasta products, as substitutes of meat, egg protein and sausages, also are cooked, roasted and ground and mixed with cereal flour in the production of bread, crisps and pasta, crisps and dietary dishes.

Phenolic acids represent the most common form of phenolic compounds in the cereal grain and many other plants. The phytochemical ferulic acid is found in the leaves and seeds of many plants, but especially in cereals. It is the most abundant phenolic acid in common cereals, representing up to 90% of total phenolic compounds. Ferulic acid has been reported to have many physiological functions, including antioxidant, antimicrobial, anti-inflammatory, and anti-cancer activities. It is an antioxidant which neutralises free radicals (superoxide, nitric oxide, and hydroxyl radical) which could cause oxidative damage to cell membranes and DNA. Like many other antioxidants, ferulic acid reduces the level of cholesterol and triglyceride, thereby reducing the risk of heart disease.

Eight individual bacteriocin-producing lactic acid bacteria (LAB) strains and three bacteriocin-non-producing cheese starter cultures were evaluated for their ability to inhibit the growth of six Listeria monocytogenes strains, originating from the guinea-pig lymph nodes, raw cow milk, and manufacturing dairy equipment. Results showed that either live cells or cell-free neutralised supernatant (CFNS) and/or heated CFNS of six individual LAB strains (Lcc. lactis subsp. lactis CCDM 416 and NIZO R5, Lbc. plantarum HV 11 and DC 1246, P. acidilactici HV 12, and Ent. mundtii CCM 1282) and one starter culture (DELVO-ADD^® 100-X DSF) were effective in the suppression of at least one listeria strain. Neither any individual LAB strain nor starter culture was antagonistic toward all studied L. monocytogenes strains, indicating diverse sensitivity/resistance among L. monocytogenes strains to antimicrobial compounds of LAB. The significant susceptibility of listerias isolated from raw milk and dairy equipment together with the strong antilisterial activity of DELVO-ADD^® 100-X DSF could be applied in dairy technology, where commonly used starter cultures could play both the biopreservative and fermentation role.

An improved screening procedure was developed for the detection of amino acid decarboxylase-positive microorganisms (especially lactic acid bacteria and Enterobacteria). Monolayer culture and double layer colour development methods for the detection of amino acid decarboxylase-positive lactic acid bacteria and Enterobacteria were established. Biogenic amine-positive bacteria strain was isolated directly from the samples. The applicability and detection level of the designed medium were quantitatively evaluated by the confirmation of the amine-forming capacity using an HPLC procedure, while tyrosine decarboxylase and lysine decarboxylase genes were detected by PCR with specific primers. The screening method showed a good correlation with the chemical analysis and molecular detection. Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Enterococcus faecium, and Enterococcus faecalis were obtained from traditional Chinese sausage. The isolation and screening of amino acid decarboxylase-positive lactic acid bacteria and Enterobacteria can be carried out simultaneously by the improved method.

Several multivariate methods including partial least squares (PLS) regression, principal component regression (PCR) or multiple linear regression (MLR) have been applied to predict wine quality, based on the definition of chemical and phenolic parameters of grapes and wines harvested at different ripening levels. Three different models including grape phenolic maturity parameters (grape), wine phenolic parameters (wine) and a combination of grape and wine phenolic parameters (grape + wine) were analysed for each of the wine sensory attributes. The grape parameter model has been presented as the best test to predict wine quality based on sensory scores. On the other hand, wine models showed lower accuracy. The combination of grape and wine parameters presented intermediate results showing sometimes good predictability. Moreover, PLS and PCR appeared as more accurate multivariate methods compared to MLR. Although MLR showed higher correlation coefficients, lower RPD values were observed, displaying thus its lower prediction accuracy. Multivariate calibration statistics appeared as a promising tool to predict wine sensory quality in an easy and inexpensive way.

Folin-Ciocalteu reagent (FCM) and Price and Butler method (PBM) were used for spectrophotometric determination of the total content of phenolic compounds in 29 wines (8 white, 21 red). The average contents of phenolic compounds determined by FCM and PBM were 108 (90-119) and 105 (90-129) for white wines, and 1545 (874-2262) and 547 (306-816) mg/l of gallic acid equivalents (GAE) for red wines, respectively. The reason for the lower PBM values in red wines is the higher reactivity in PBM of phenolic compounds, especially of gallic acid generally used as a standard in the above methods. The higher reactivity of the standard means that the measured absorbance of the sample responds to a lower concentration. The average total antioxidant activities determined by TEAC (Trolox Equivalent Antioxidant Capacity), FRAP (Ferric Reducing Antioxidant Power), and DPPH (using diphenyl-p-picrylhydrazyl radical) were 5.14 (4.30-6.14), 1.43 (0.86-2.14), and 0.71 (0.61-0.81) of Trolox equivalents (TE) and 26.44 (13. 9-34.4), 9.43 (4.92-13.9), and 5.52 (2.91-8.62) mmol/l TE for white and red wines, respectively. Almost the same molar absorptivities with TEAC and DPPH methods were found while with FRAP method it was somewhat higher (about 1.56-times). The ratio of the values determined by FRAP and DPPH methods for white and red wines were 2.0 and 1.7, respectively. The TEAC values were 2.8- and 4.8-fold higher than those determined by FRAP and DPPH methods, respectively. The radical ABTS*+ used in TEAC method is therefore the most reactive and responds to the highest number of hydroxyl groups of the phenolic compounds of wines.

The effect of modified atmosphere packaging (MAP 1 - 80% O₂ + 20% CO₂ and MAP 2 - 90% CO₂ + 10% N₂) on selected chemical and sensory parameters of common carp steaks stored at 3 ± 0.5°C, and determination of the shelf life of the products was studied in this research. Samples were analysed on day 1, 3, 5, 7, 9, 11, 13, 15, and 17. An increase in TVB-N values in carp steaks followed the order: MAP 2 < control < MAP 1. From day 9 of storage FFA concentrations were higher (P < 0.01) in MAP 2 samples compared to control and MAP 1 samples. The presence of oxygen (MAP 1 and control) resulted in an increase in TBA values in comparison with samples packaged in the absence of oxygen. According to sensory evaluation, it was concluded that carp steaks packaged in modified atmosphere with 80% O₂ + 20% CO₂ remained acceptable up to 15 days of storage, whereas samples packaged under 90% CO₂ + 10% N₂ as well as samples kept on flaked ice remained unchanged until the end of the experiment.

The objective of this work was to verify the effect of the lean meat proportion on the chemical composition of the meaty parts (loin and ham) of pork. A total of 116 finishing hybrid pigs commonly used in the Czech Republic were fattened for this purpose. The pigs were divided according to the lean meat proportion criterion into 3 groups, i.e. more than 60.0%, 55.0-59.9% and 50.0-54.9%. Representative muscle samples were taken from the right halves of these pigs. They were then homogenised and submitted to chemical analysis. The results of the measuring showed that the values of the water content, intramuscular fat (IMF), crude proteins, and ash matter ranged in the loin between 72.50-72.80%, 1.56-1.96%, 23.20-23.40%, and 1.37-1.40%, respectively, and in the ham between of 70.43-71.59%, 3.52-4.26%, 21.67-21.95%, and 1.42-1.56%, respectively. The ascertained values of the water content and crude proteins with regard to the increasing lean meat proportion in the carcasses did not show any developmental tendencies. As for the content of IMF, it was determined that the higher was the lean meat proportion, the lower was the IMF content. Concerned of sensoric quality traits it means that pork meat from supermeaty hybrid pigs shows lower quality. Concerning the content of ash matter, it was observed that the ash content increased with an increasing lean meat proportion. In the carcass part of the musculus longissimus lumborum et thoracis (MLLT), it was demonstrated that the higher was the lean meat proportion, the lower was the content of amino acids - threonine, isoleucine, lysine, aspartic acid, serine, and proline. From point of the production of exceedingly meaty pigs (over 60%), it can be expected a worse nutritional pork meat value. In the carcass portion of the musculus semimembranosus (MS), the contents of valine, isoleucine, phenylalanine, lysine, serine, proline, and glycine increased with an increasing lean meat proportion. Within the framework of statistical evaluation of differences between the groups, the values of IMF ((P ≤ 0.01) in MLLT, water content, IMF, ash matter, threonine, valine, phenylalanine, lysine, aspartic acid, serine, glycine, and alanine in MS were highly significant ((P ≤ 0.05; (P ≤ 0.01 and (P ≤ 0.001).

Germinated seeds are rich in various nutrients but are vulnerable to fungal contamination which favours micromycete formation on the sprouts. The main aim of this work was an investigation of strategies to reduce the contamination of sprouted seed foods. Over the course of 96 hours of sprouting, seeds of organic spring wheat (Triticum aestivum L.), winter wheat (Triticum aestivum L.), naked oat (Avena nuda L.), triticale (xTriticosecale) and rye (Secale cereale L.) were irrigated in water filtered using the Pazdroid Med-1500 filtration device with and without 4% ethyl alcohol. Germinated seeds were stored at 18°C for one, three and seven days and the levels of Mucor spp., Penicillium spp., Alternaria spp., Aspergillus spp., Fusarium spp. and Bipolaris spp were determined. Micromycete numbers were greater in sprouted winter wheat and rye but were reduced when these were soaked and irrigated with filtered water and filtered water containing 4% ethyl alcohol. Filtered water led to greater reductions in micromycete numbers in sprouted winter and spring wheat than in other seeds.

Off-flavour in soft drinks is one of the main threats to manufacturers, which can result in expensive recalls, and discredit the brand. Off-flavours can occur for a variety of reasons (e.g . chemical contamination of raw material). The presented case study has proved there is a relationship between the identification of biphenyl and its derivatives in the used preser vative (benzoate) and off-flavours in the drink . The project consisted of three phases: (1) the assessment of the probable cause of off-f lavours based on sensor y evaluation and GC-MS -Olfactometr y profiling of volatiles; (2) the quantification of biphenyls and the characterisation of their sensor y properties; (3) the screening of commercially available benzoates for the presence of biphenyls. Based on the odour threshold obtained by GC-O (0.03 mg/l for 4-methyl-1,1'-biphenyl and 0.02 mg/l for biphenyl in an aqueous solution) and the common benzoate content in soft drinks (0.14 g/l), the 'non-obser vable sensory' levels of contamination were determined to be maximally 0.143 mg/g of benzoate for biphenyl and 0.214 mg/g of benzoate for 4-methyl-1,1 '-biphenyl .

Microbial quality of ultra-high temperature (UHT) milk is usually ascertained by a total bacterial count (TBC) cultivation. But this is time consuming, so there is a tendency to search for faster and simpler methods. We compared three instruments, focusing on shortening the detection time and their suitability for practical use in dairy plants. Two of them, RapiScreen Dairy 1000 and Promilite III, detect microbial contamination by measuring adenosine triphosphate bioluminescence; the third, GreenLight, is based on oxygen consumption analysis. In the laboratory experiments, samples of UHT milk, were spiked with low concentration of microorganisms and then the level of microbial contamination was evaluated using the above-mentioned instruments together with cultivation method as a control. The instruments were also applied in a dairy plant to test 182 real samples. All investigated methods determined microbial quality faster than the TBC, but in some cases false positive and false negative results were obtained. Therefore, precise testing including optimizing pre-incubation time for bacteria enrichment is needed prior to industrial use.

The effect of taxifolin (TXF) with starter cultures (SC), such as Leuconostoc carnosum, or a mixture of strains Pediococcus pentosaceus and Staphylococcus xylosus, on the TXF stability was evaluated. UPLC analysis demonstrated that after 181 days of storage total TXF content was the highest in samples with TXF and L. carnosum (60%), compared to the 1st day of storage. The sausages with TXF and the mixture of P. pentosaceus and S. xylosus (56%) followed next. The samples treated only with TXF retained 40% of TXF, compared to the 1st day of storage. TXF had no significant effect on the growth of lactic acid bacteria. The accumulation of biogenic amines (BA), including histamine and putrescine, was more effectively reduced in sausages inoculated with the TXF plus P. pentosaceus and S. xylosus mixture. Using this mixture, the rate of lipolysis and processes of lipid oxidation were effectively slowed down. Fatty acid (FA) composition was stable in all cases.

The cell survival in the digestive tract is one of the main criteria required for the probiotics. The aim of this study was to evaluate the stability of the selected lactobacilli (Lactobacillus acidophilus CCDM 151; L. casei CCDM 198; L. rhamnosus CCDM 150, and L. fermentum ST 68) in conditions simulating those in the gastrointestinal tract as compared to the commercial probiotic strain Lactobacillus casei LAFTI L-26. The growth of lactobacilli decreased both after 2 h and 4 h incubation in MRS media with increasing concentration of bile salt but all lactobacilli had the ability to adapt in the environment of bile salt. Great differences in viability were detected between the isolated cells in the stomach simulating conditions. L. casei LAFTI L-26 and L. acidophilus CCDM 151 were most stable, L. rhamnosus CCDM 150 did not survive under these conditions. Milk revealed a strong protective influence on the viability of all lactobacilli in the stomach simulating conditions. The conditions existing in the small intestine did not influence the cell viability. Differences in autoaggregation were also observed.