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The probiotics are extremely sensitive to various environmental factors, which imposes limitation on their health and functional effectiveness. Thus, development of delivery system for protection of viable cells while passing through different stages of the human digestion system is key factor in application of probiotic products. In our study, the effects of several polysaccharides such as alginate, κ-carrageenan, locust bean gum, gellan gum, xanthan gum and their combination with various prebiotic components (resistant starch, lactulose, lactosucrose) on encapsulation of probiotic Lactobacillus casei 01 strain were studied. Both regular and unregular beads with size distributions from 2 mm up to 5 mm were obtained. The encapsulation efficiencies varied from 64.4% up to 79%. Based on the texture's profiles, the capsules can be grouped into 5 clusters with squared Euclidean distance 3.5. Meanwhile, the starch-alginate and the lactosucrose LS55L - alginate beads were found to be the most stable and to have massive textural properties, whereas the gellan gum - xanthan gum and the chitosan coated alginate beads emerged as the softest. Encapsulation significantly improved the degree of gastric tolerance of probiotic cells even in the presence of pepsin. The INFOGEST in vitro digestion protocol was adapted to investigate the protection effects of different capsules. The highest survival (with loss rate of lower than 1 log CFU/g) was observed in the case of the cells encapsulated in starch-alginate beads. Moreover, the alginate microcapsules combined with lactosucrose LS55L also provided very promising shield for probiotics from the low pH of gastric conditions. Our findings suggest that incorporation of prebiotics into alginate-base encapsulation would be good idea in development of micro delivery systems that helps the survival of probiotics and their delivery to the target sites of action in human body.

Xylo‐oligosaccharides (XOS) are nondigestible oligosaccharides (NDO) which are recently authorized as novel food ingredients in European Union. Present study introduces the effect of XOS on baking quality of cookies. Color measurements proved that XOS enhance the caramelization during baking. Texture profile, geometry, and baking loss of cookies showed little changes due to XOS addition indicating that XOS are easy to incorporate into baking products. Based on sensory evaluation by expert panel, it was observed that XOS increased the “baked character” of the cookies as indicated by the increased caramel flavor, darker color, and crispier texture. XOS addition also increased the sweet taste and global taste intensity of cookies suggesting that in bakery products XOS evolve a flavor enhancer role. XOS proved to be a promising new alternative to increase dietary fiber content of cereal‐based cookies., Xylo‐oligosaccharides (XOS) were used for dietary fiber enrichment of cookies. Texture profile, colour and sensory attributes have been measured. It was concluded that XOS enhance brown colour, crispy texture and “baked character” of the cookies.

Present study introduces the previously not‐described rheological properties of a nondigestible oligosaccharide: xylo‐oligosaccharide which is a novel food ingredient in Europe. Significant differences were observed among viscosity of solutions of different formulas (liquid or powder) of XOS. Thickening potential of XOS in aqueous media compared to that of sucrose (Suc) or fructo‐oligosaccharides strongly depends on utilization level: At low concentration, XOS proved to be weaker while at high concentration to be stronger than fructo‐oligosaccharides. Differences in viscosity of XOS, FOS, and sucrose were much higher at below 60°C than at higher temperatures. Storage and loss modulii of xanthan gum gels were not influenced while those of locust bean gum were affected negatively by XOS addition. Addition of XOS at low concentrations did not decrease gelatin gel strength but increased gelatin gel stability against mechanical stress. XOS proved to have different rheological behavior from previously used oligosaccharides., Present study introduces the previously not‐described rheological properties of a nondigestible oligosaccharide: xylo‐oligosaccharide. We investigated the thickening potential of XOS in aqueous media compared to that of sucrose and fructo‐oligosaccharides. Results indicated that texture‐modifying potential of XOS is different from previously used oligosaccharides, and therefore, it should be taken into account during food product development.

In our tests, we artificially infected liquid whole egg samples with Salmonella enteritidis, Listeria monocytogenes, and Staphylococcus aureus bacteria, and then treated the samples in “Food Lab900” high hydrostatic pressure (HHP) instrument for 3–17 min at 200–400 MPa. Subsequently, the change of the viable cell count of the specific bacteria has been tested. In addition to the samples infected with various bacteria, non-infected samples were also treated in each test and the change in viable cell count, colour and viscosity of the samples upon the effect of the treatment. In summary, it can be concluded that in each test of our investigations, the viable cell count of S. enteritidis critical for egg products is reduced significantly, while the reduction of the total viable cell count was around two magnitudes. Additionally, based on our results, microbial destruction, reduction of enthalpy (denaturation of egg white) caused by the treatment at HPP, and colour change are primarily affected by the pressur...

Resistant starches (RS) can be used in the food industry aiming to enhance the dietary fibre content and reduce the glycaemic response of food. The aim of the present study was to investigate the physical and chemical properties of different resistant starches (origin, type of resistance) and their comparison with native starches in pure form and in stoichiometric mixtures. Measurements were carried out to determine enzymatic digestibility, water absorption, thermogravimetric parameters (DSC), and viscometric characteristics (RVA) of resistant and native starches and their mixtures. Enzymatic digestibility and water absorption were reduced linearly by adding resistant starches into the mixtures. RVA parameters have shown non-proportional character in the stoichiometric mixtures. The results of DSC measurements proved that the gelatinisation of resistant starches is quite different and only chemically modified resistant starch was heat-sensitive. Results indicated that circumspect evaluation is needed in the selection of resistant starch products for the development and innovation of food products with reduced glycaemic response.

The relationship between amylose to amylopectin ratio and functional properties of maize starch blends (system I) and “model mixtures” (system II) made of waxy and high amylose maize starch were investigated using the Rapid Visco Analyser (RVA). A 4-5% difference in amylose content caused significant difference in RVA curves and their first derivatives. Based on the first derivative of the RVA curves four different parameters (Peak 2, Peak Time 2, Peak 3, Peak Time 3) were defined. Peak viscosity and parameters were negatively correlated with amylose content confirming that amylopectin is mainly responsible for water uptake. The final viscosity of starch was very high and decreased as amylopectin or amylose was added, indicating that this parameter is the most sensitive to interactions in starch. In system II amount and characteristics of amylopectin seemed to primarily determine the pasting properties. Traditional RVA curves and parameters proved to be feasible to detect the differences between gel properties of the two systems after cooling. First derivative viscograms and alternative parameters seemed to be suitable to demonstrate the importance of interactions between the starch components during gelatinization. Our results confirmed that the Rapid Visco Analyser is a sensitive rheological tool for evaluating effects of starch structure and chemical composition on functional properties providing valuable help for food technologists.

The physical, chemical, and morphological changes of maize seeds during germination were investigated using near-infrared spectroscopy (NIR) and a method based on the Rapid Visco Analyser (RVA). Near-infrared spectra provide information about both chemical and physical changes that occur in maize seed. The RVA curves make it possible to follow the process of germination. Four RVA parameters (peak viscosity, final viscosity, trough, and setback) were linearly correlated with germination time (R = 0.64–0.96), while the first derivatives of RVA curves contain specific information about starch structure. Water-soluble protein (WSP) content of germinated maize seeds was measured using a flow injection analyser; this technique proved to be suitable for monitoring germination by following the mobilization of proteins. WSP and RVA parameters were highly correlated (R2 = 0.82–0.95) with predicted values calculated from NIR spectra of dry samples. Strong intercorrelations existed between NIR spectra and vi...

The process of germination in six different wheat cultivars was monitored using NIR spectroscopy and the Rapid Visco Analyser (RVA) method. Near-infrared spectra provided insight into both chemical and physical changes that occur in the seed, in particular mobilization processes involving carbohydrates. RVA curves also contain physical and chemical information and can be interpreted as physicochemical spectra. The process of germination was followed sensitively through the RVA curves and some rheological parameters (peak viscosity, trough, breakdown, final viscosity, and setback) were highly correlated (R = 0.95–0.98) with predicted values calculated from NIR spectra. Viscosity data calculated from RVA curves collected at 200–480 sec showed the most characteristic changes during the early heat treatment stage of the pasting procedure. Strong intercorrelations were found between viscosity data and NIR spectra from the beginning of the swelling and gelatinization processes in germinating seed. The ...

Seed development (maturation) and seed germination (mobilization) are characteristic phases of the life cycle of plant materials. During these complex metabolic, enzymatic, morphological and structural processes different anabolic and catabolic reactions take place in the seed in highly hydrated conditions. The maturation process can be characterized by the fast formation/decline of monosaccharides and amino acids in the early phase of seed development. In the second phase of maturation the synthesis and polymerisation of reserve carbohydrates and proteins are characteristic. During germination processes modifications in grain include the activation of preformed hydrolytic enzymes, biosynthesis of de novo synthesised enzymes and degradation of the storage compounds in the endosperm. The starch and reserve protein mobilization is accelerated during the first three days of germination and the amount of liberated soluble proteins, free amino nitrogen and sucrose content increase dramatically. Both maturation and germination processes need high moisture content, however, the migration of water is hindered by membranes and by interactions with different solutes and macromolecules. The status and changes of water and other main constituents were measured by near infrared (NIR) spectroscopy. This method allows insight into the hydration and dehydration process of physiological events in intact seed samples and also measures the changes of chemical constituents like protein, total nitrogen and polysaccharides. Results confirmed that the combination and overtone bands of water were sensitive indicators of changes in water and they can be used as parameters for detecting the status and changes of water clusters during hydration/dehydration processes in maturing and germinating seed. The changes of carbohydrates and proteins can also be unscrambled from reflectance spectra. NIR spectroscopy can, therefore, be used as a sensitive tool to optimise detection of the stage of growth during maturation and also to evaluate the biochemical and structural processes taking place in germinating seed.