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The sorption isotherm (SI) of dried tomatoes was studied at three different temperatures, 15, 25, and 35 °C, using a static gravimetric method. The modified forms of the Guggenheim-Anderson-de Boer (mGAB), Halsey (mHAL), Henderson (mHEN), and Oswin (mOSW) models that incorporate the temperature term in their equation were selected and used to describe the experimental data of dried tomatoes. The mGAB model best described the SI of dried tomato samples at individual temperatures, having the highest coefficient of determination (R²) and the lowest sum of squares of errors (SSE), the root mean square error (RMSE), and the corrected Akaike information criterion values (AIC_c). However, based on the statistical indices, three other tested models outperformed the mGAB model in describing the multi-temperature estimation to differentiate the temperature effect. The mOSW and mHAL models were superior in this case.

This research aimed to optimise a pilot-scale formulation for seamless scale-up, considering critical variables such as the honey-to-maltodextrin ratio, temperature, and drying time. Employing response surface methodology with a central composite design approach, the investigation systematically assessed the impact of four key factors within predetermined upper and lower limits: honey volume (90–900 g % dry basis), maltodextrin (60–600 g), drying temperature (60–70 °C), and drying time (180–300 min). Subsequently, these factors were randomised and optimised using the Design Expert software system. The analysis of variance revealed the significant impact of each drying factor, their interactions, and squared squares on the honey-to-maltodextrin ratio, as well as the effects of drying temperature and time. Validation results underscored the model reliability, exhibiting narrow standard deviations ranging from 0.001% to 1.3%. These outcomes emphasise the efficacy of Response Surface Methodology (RSM) and Central Composite Design (CCD) in refining formulations, offering valuable insights into appropriate product development and a seamless scale-up process.

This study aims to characterise the physicochemical properties and stability of confectionery glazes made from various tropical fruit seed powders during storage. Physicochemical properties were evaluated at regular intervals throughout frozen storage to monitor quality changes. The mango seed glaze is slightly acidic, and significantly darker, with tones of green and blue. The glaze has a total soluble solid content of 73.37 °Brix, a moisture content of 19%, hardness of 46.69 g, and sagging capacity of 18.33 mm, which ensures both structural integrity and sensory appeal. Its highest viscosity among formulations suggested possible thickening and improved stability. Over 28 days, significant changes occur, with the pH stabilising to a near-neutral 6.8. The hue changes over time, migrating towards reddish tone as indicated by increasing positive a* values, while maintaining a consistent preference for blue-toned hues with continuously negative b* values. Moisture levels remained stable at 18.71% during storage, with minimal total soluble solid content changes, indicating sustained quality. The findings suggest that mango seed glazing is a viable option for quality preservation during storage. This study provides essential empirical insights into the potential changes in the quality characteristics of various fruit seed glazes when subjected to freezing.

Sweet cherry juice rich in phenols and anthocyanins is highly perishable and typically undergo thermal pasteurisation, which can diminish its nutritional composition. High pressure processing (HPP), a non-thermal technique using pressure to inactivate the microbes while preserving nutrients, offers a more effective alternative for extending the shelf life of fruit juice. Accordingly, present study evaluated comparative impact of high pressure processing and thermal pasteurisation on phytochemicals, antioxidant activity, microbial and sensory attributes of cherry juice during storage. For study, cherry juice subjected to two different HPP levels (400 and 600 MPa) for 5 min and thermal pasteurisation (95 °C) for 30 s, followed by storage (60 days at 4 °C). Results showed HPP and thermal pasteurisation had significant impact (P < 0.05) on phenolics, flavonoids, and antioxidants compared to control, however, thermally pasteurised juice showed rapid deterioration compared to HPP juice, whereas anthocyanin and cyanidin-3-glucoside levels remarkably different in both groups. Microbial findings revealed safety of HPP pasteurisation juice with shelf life (45 days) however, better sensory acceptability for HPP treated juice. In nutshell, HPP pasteurisation is pragmatic approach for enhancing shelf life with better nutrients for cherry juice and findings useful for beverage industry and health professionals.

The presence of immature coffee beans reduces the quality of the coffee brew. This study evaluated how the acetic acid affected the aroma and taste of immature compared to mature Robusta coffee. The naturally processed immature Robusta green beans were immersed in acetic acid (0–5%) for 30–90 min. The naturally processed mature Robusta green beans were used as a control treatment. The samples were roasted at a medium level (240 °C, 14 min). The sensory analysis was evaluated by the cupping test by a trained and certified panellist (Q-Grader). Acetic acid immersion significantly improved the sensory quality of immature beans (P < 0.05). Specifically, immersion in 3% acetic acid for 90 min yielded the highest sensory score of 84.92. According to the Coffee Quality Institute (CQI) classification, this score falls into the 'Fine' Robusta classification. The 0% 30-min, 3% 30-min, and 3% 90-min treated immature samples and an untreated control mature sample were analysed for pH, caffeine, chlorogenic acid, and volatile compounds. The treatment significantly decreased the chlorogenic acid (P < 0.05) and increased the volatile compound concentration of furans, ketone, pyrrole, aldehyde, and ester while decreasing pyrazines, sulphur, phenol, and alcohol. This study effectively enhanced immature Robusta taste and aroma quality to a degree comparable with mature Robusta coffee beans.

In this paper, desorption isotherms of two jerky products were studied (whole-muscle jerky – sample 1 and minced jerky – sample 2). The work focused on the comparison of the Dynamic Dewpoint Isotherm (DDI) method and the Saturated Salt Slurry (SSS) method and testing the newly applied model for modelling desorption isotherms for dried meat. Data were statistically processed using 8 models [Guggenheim-Anderson-de Boer (GAB), Double Log Polynomial (DLP), Henderson, Chin, Smith, Oswin, Hasley, and newly applied model] and statistically evaluated using coefficient of determination (R²), root mean squared error (RMSE) and mean relative percentage deviation (P-value). The DLP model (25 °C) reached R² ≥ 0.999, P-value ≤ 1.84 for DDI, and R² ≥ 0.998, P-value ≤ 4.37 for SSS method. The GAB model reached R² ≥ 0.997, P-value ≤ 2.58 for DDI, and for SSS method the GAB model reached R² ≥ 0.998, P-value ≤ 5.47. The new model reached P-value ≤ 5.73 for DDI and P-value ≤ 3.48 for SSS method. All models reached the P-value < 10% except for Smith and Chin models. The DDI method and newly applied model prove to be a suitable and precise approach to the evaluation of isotherms of dried meat products.

The present investigation explored the possible use of Thymus vulgaris essential oil (TVEO) as a beverage antifungal preservative instead of chemical ones. The chemical profile of TVEO exposed carvacrol (60.47%) as the predominant compound. The antifungal properties of TVEO were assessed on various food spoilage yeast and mould species using two tests. TVEO showed a powerful antimicrobial effect against all the fungal strains at the three volumes of essential oil (EO) used (i.e. 10, 20, and 30 µL). The minimum inhibition concentration (MIC) of TVEO was also evaluated and ranged from 0.0625% to 0.015% (v/v). Furthermore, the potency of TVEO as a beverage antimicrobial preservative was tested at four distinct concentrations (0.6, 1.25, 4, and 6 μL·mL^–1) against Saccharomyces cerevisiae alone and combined with medium heating (70 °C for 2 min) in a real food matrix (Orangina^® drink) for eight storage days. TVEO exhibited a significantly higher preservative effect than chemical preservatives (sodium benzoate and potassium sorbate). Lastly, a molecular docking examined the mechanism of action of carvacrol against two crucial enzymes in S. cerevisiae viability [ERG2 (sterol C8-isomerase) and ERG3 (sterol C5-desaturase)] compared to a chemical preservative (potassium sorbate). The two ligands highly interacted with the two target enzymes. However, carvacrol achieved a better score than potassium sorbate against ERG2 and ERG3, with binding energy of –10.19 kcal·mol^–1 and –11.73 kcal·mol^–1, respectively. Our results open up the perspective of using TVEO as a natural food preservative.

Because grape pomace powder (GPP) contains abundant phenolic chemicals and fibres, GPPs can serve as a filler in developing novel food products. This study examined how the GPP amounts affected a composite flour's physicochemical properties and bakery snacks' chemical, technical, and sensory properties. The experimental procedure involved replacing wheat flour (WF) with GPP at 5–20% while maintaining 100% WF as the control. The addition of GPP resulted in a significant decrease in the oil absorption capacity (P ≤ 0.05), while the rehydration index and water absorption capacity increased (P ≤ 0.05). The peak length (5.44–5.90 min), pasting temperature (70.20–80.92 °C), peak viscosity (124.72–172.80 RVU; RVU – relative value unit), trough viscosity (60.76–82.04 RVU), breakdown viscosity (69.56–93.74 RVU), final viscosity (162.70–222.30 RVU), and setback viscosity were measured. The addition of GPP to the composite flour and snacks decreased the lightness (L*) and increased the redness (a*) and yellowness (b*). The items' higher dietary fibre (DF) allowed them to claim 'high fibre content' when the maximum GPP was added. The GPP also increased the snacks' total solids, protein, ash, fibre, total phenolics content (TPC), and antioxidant capacity. The sensory acceptability of the snacks made with 5–10% GPP instead of WF was higher.

Abstract: Phloridzin (phloretin-2'-O-glucoside) is a phenolic compound characteristic of the genus Malus. This study aimed to evaluate phloridzin as a marker of undeclared addition of apples in fruit products. To test this proposal, the heat and oxidation stability of phloridzin was firstly confirmed. Then the distribution and variability of phloridzin in apples were studied, showing no difference between the tested apple varieties (Golden Delicious, Granny Smith, Rubin and Champion) but a significant difference in phloridzin content in seeds (2 380 ± 755 mg kg^-1) compared to peel, flesh and core, which contained less than 70 mg kg^-1. The effects of different stages of apple purée production at an industrial scale were also investigated. The kinetics of phloridzin diffusion from seeds to apple homogenate played an important role in the final phloridzin content in 16 analysed apple purées (26-39 mg kg^-1). Finally, the survey of phloridzin content in 31 fruit products in the market was carried out. Phloridzin was also measured in eight jams and fillings which did not declare the presence of apples on their labels; findings from 2 to 6 mg kg^-1 indicate the addition of apples from 5% to 20%. It was confirmed that phloridzin appears to be a suitable marker for detecting the undeclared presence of apples, which are a cheap substitute for the declared fruit types.

Aquatic foods such as fish, shrimp, and shellfish are important human nutrient sources. However, aquatic foods spoil quickly during processing and storage due to spoilage bacteria and endogenous enzymes. Ultra-high-pressure (UHP) technology, as an advanced non-thermal treatment method, is an effective preservation technique for aquatic foods. The mechanism of UHP technology is to destroy non-covalent bonds by UHP, which leads to the change of cell membrane permeability and the destruction of high-level structure of proteins, making apoptosis and enzyme inactivation. The technology can effectively sterilise and preserve food's colour, taste and nutritional value. The paper provides an introduction to the working principles, types, sources and equipment and describes the progress of the research and application of UHP technology in pascalisation, enzyme inactivation, parasite inactivation and quality modification of aquatic products. Potential limitations and prospects of the technology are also outlined. We hope to lay the theoretical groundwork for using this technique in aquatic product processing and provide guidance for its application in industrial production.

Among the varieties of pineapples, honey pineapple is suitable to be processed as a probiotic beverage. The study aimed to evaluate the honey pineapple juice as a growth medium for Lactiplantibacillus plantarum subsp. plantarum Dad-13 probiotic strain. The pineapple juice was fermented by adding a starter culture of L. plantarum Dad-13. The fermentation time (0, 4, 8, 12, 16, 20, and 24 h) was used as a variable. The number of L. plantarum Dad-13 cells increased significantly after fermentation (P < 0.05). In acidic pineapple juice L. plantarum Dad-13 can still grow more than 2 log cycles. After 16 h, the results showed the best characteristics with cell count (8.86 log CFU·mL^–1), pH (3.52), and titratable acidity (0.59%). To balance the sour taste, the 8% sucrose addition was the most preferred by the panellists (n = 67), with a 5.74 (slightly like) overall acceptance score. After 42 days, there was no significant decrease in cell viability. The number of cells on day 42 was 8.81 log CFU·mL^–1 with significant changes in pH and titratable acidity. The study showed that honey pineapple juice is a suitable growth medium for L. plantarum Dad-13.

Plants are permanently exposed to biotic and abiotic stress and have therefore developed intricate resistance mechanisms, consequently. These include the presence of microbial endophytes, which can promote plant growth and ensure better resilience against unfavourable conditions. These microorganisms colonising plant tissues can directly affect plant growth by producing phytohormones, antioxidants, 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, or indirectly by the production of siderophores and antifungal agents. To the best of our knowledge, this is the first study devoted to assessing bacterial endophyte diversity and their plant growth-promoting properties in two utterly distinct vineyards in view of agricultural management (conventional, biodynamic) in the Czech Republic. With these different agricultural approaches, we hypothesised different numerical representations of bacterial endophytes acquired from vine shoots and leaves, which was not proved (P = 0.743, F = 0.129). A total of 470 distinct bacterial endophytes were isolated from the Vitis vinifera plants from the conventional and biodynamic vineyard and from which over 80% were identified by the matrix-assisted laser desorption-time-of-flight mass spectrometry (MALDI-TOF MS). In both vineyards, the dominant bacterial genus was Bacillus, followed by Pantoea, Pseudomonas and Staphylococcus. Plant-promoting endophyte properties varied with respect to the season and type of vineyard. The ability to produce indole-3-acetic acid (IAA) and ACC deaminase was higher in the biodynamic vineyard, in comparison with antioxidant activity, which was found in a higher proportion in isolates from the conventional vineyard.

The purpose of the present study was to develop edible composite films based on sodium alginate and pectin with incorporated Aronia melanocarpa (Michx.) Elliot and Thymus serpyllum L. extracts. The influence of the extracts on the physicochemical, optical, mechanical, and antioxidant properties of the films was investigated. The addition of the extracts changed the colour parameters and significantly increased the barrier properties to UV and visible light. This effect is more pronounced in the film with chokeberry extract and is due to the anthocyanins contained in it (75.43 μg cyd eq·g^–1, cyd eq – cyanidin equivalents). The antioxidant activity of films with incorporated extracts was 4-fold (thyme) to 7-fold (chokeberry) higher than the control alginate/pectin film. A significant improvement in the mechanical characteristics of the films with extracts was found. The values for tensile strength were 9.41 MPa (chokeberry) and 9.54 MPa (thyme), while for the film without extract – 4.63 MPa. The resulting films could find potential application as active packaging with antioxidant properties, which could increase the quality and extend the shelf life of the foods packaged in them.

Nutrition plays an important role in human life. So far, there have been discussions focusing on the nutritional value of individual foods, separate dishes, or daily meals. However, they have not taken into account the composition of the diet in the longer term. The aim of this work was to evaluate a full-day diet from a currently renowned company that is producing box diets on the Czech market against a full-day diet of twenty randomly selected students. The results showed that the box diet met the required amount of protein, fat, vitamin E, cholesterol, and also the optimal intake of n-6 and n-3 fatty acids. The amount of saturated fatty acids (SFA) was only slightly increased. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content averaged 38 mg day^-1, which did not meet the current requirements. The students' full-day diet was variable, the individual differences were large. Protein intake could be assessed as sufficient in most cases. The total fat intake ranged from 21 g day^-1 to 126 g day^-1. Seven out of twenty samples would satisfy the recommendation for SFA. The content of the essential acids EPA and DHA was below the detection limit with the exception of one sample (containing herring fillets).

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).

To meet rapid and non-destructive identification of selenium-enriched agricultural products selenium-enriched millet and ordinary millet were taken as objects. Image regions of interest (ROI) were selected to extract the spectral average value based on hyperspectral imaging technology. Reducing noise by the Savitzky-Golay (SG) smoothing algorithm, variables were used as inputs that were screened by successive projections algorithm (SPA), competitive adaptive reweighted sampling (CARS), uninformative variable elimination (UVE), CARS-SPA, UVE-SPA, and UVE-CARS, while sample variables were used as outputs to build support vector machine (SVM) models. The results showed that the accuracy of CARS-SPA-SVM was 100% in the training set and 99.58% in the test set equivalent to that of CARS-SVM and UVE-CARS-SVM, which was higher than that of SPA-SVM, UVE-SPA-SVM, and UVE-SVM. Therefore, the method of CARS-SPA had superiority, and CARS-SPA-SVM was suitable to identify selenium-enriched millet. Finally, 454.57 nm, 484.98 nm, 885.34 nm, and 937.1 nm, which were obtained by wavelength extraction algorithms, were considered as the sensitive wavelengths of selenium information. This study provided a reference for the identification of selenium-enriched agricultural products.

This study aimed to produce yogurt with Ganoderma lucidum residues and selected probiotic bacteria. To select the most potent GABA-producing strain (GABA - γ-aminobutyric acid), nine probiotic bacteria were subjected to the glutamate decarboxylase (GAD) activity assay. Limosilactobacillus reuteri DSM 17938 was selected and used in preparing fresh yogurts, with and without supplementation of Ganoderma residues obtained after water extraction [GW (Ganoderma waste) 2% (w/v)]. A decrease in pH during fermentation and the occurrence of syneresis were investigated. Lactic acid bacteria (LAB) viability and anti-Escherichia activity were estimated. Further, the cytotoxic effect of yogurt extracts on the human colon cancer cell line (HCT116) was surveyed. Besides functionality, the sensory attributes were evaluated. The pH values did not significantly change with the GW addition while increasing the LAB counts [up to 9.76 ± 0.11 log colony-forming units (CFU) mL^-1] and the cytotoxic effect on HCT116 cells. Yogurt produced with selected bacteria and GW had the most valuable anti-coli effect against E. coli 0157: H7 and E. coli ATCC 35218 (American Type Culture Collection, Rockville, Maryland) (4.81 ± 0.62 and 5.64 ± 0.29 CFU mL^-1, respectively). Although the added GW increased the yogurt functionality, it had a slightly negative effect on the taste and texture of the partially modified recipe. Yogurts fortified with GABA-producing strain and GW could potentially reduce relapse rates of depressive disorders.

The objective of this research was to evaluate the effect of blackcurrant mash blended with apple pulp during juice production and storage on its phenolic composition, antioxidant activity, L-ascorbic acid, and colour. Five variants of samples were prepared: apple juices from two cultivars: the Shampion and Idared cultivars without and with 20% of blackcurrant pulp and blackcurrant juice which were stored at 4°C and 30°C for 6 months. The apple juices prepared from the Idared and Shampion cultivars had a very low L-ascorbic acid contents (1.32 mg/l and 6.26 mg/l, respectively) whereas blackcurrant juice showed the highest amount of L-ascorbic acid, i.e. 704.3 mg/l. The addition of 20% of blackcurrant pulp before apple crashing resulted in a great difference between L-ascorbic acid contents in juices. The addition of blackcurrant fruits before apple crushing had a statistically significantly different (P < 0.05) influence on phenolic compounds, especially in Idared blended pulp. As compared with the control samples, flavan-3-ol concentration increased 4 times in juices made from 80% of Idared apples blended with 20% of blackcurrant fruits. Apple pulp blended with blackcurrant was richer in hydroxycinnamic acids (especially caffeic, p-coumaric, and neochlorogenic acids) than juices made only from apples. The results ranged from 83.05 to 3297.6µM T/100 ml for DPPH (1,1-diphenyl-2-picrylhydrazyl radical), from 20.64 to 490.93µM T/100 ml for ABTS (2,2'azinobis-(3-ethylbenzthiazoline-6-sulphonic acid)), and from 1.52 to 37.35µM T/ml for FRAP (Ferric reducing antioxidant power assay) for apple juice made from the Idared cultivar and for blackcurrant juice, respectively. The highest level of the antioxidant capacity (P < 0.05) observed in the blackcurrant sample was due to the effect of the high anthocyanin and ascorbic acid contents. The apple juice colour showed a moderate degradation with time as indicated by the slight reduction of L* values in the samples stored at 4°C for 6 months, and a much higher decrease of L* values in the samples stored at 30°C. The lightness of the apple blended with blackcurrant increased during storage as a result of the coloured anthocyanin degradation. The temperature during the sample storage (30°C) had a significant influence, resulting in a higher degradation of all phenolics compounds analysed, colour and antioxidant activity.

Wheat, apple, potato, and bamboo fibres were applied at 1 and 3% content to bread wheat flour and these additions were studied for the quality of dough and bakery products characterised by farinograph parameters, laboratory baking tests, firmness, and sensory analysis. The addition of fibre caused a decrease of loaf volume, also a change of crumb colour and a slight increase of bread crumb firmness. On the other hand, the addition of fibre affected the farinograph parameters, significantly decreased the specific volume especially at 3% fibre (P < 0.05). A statistically significant difference (P < 0.05) in firmness was found out between products with added wheat and bamboo fibre. Statistically highly significant differences (P < 0.001) were found among the other pairs of products with fibre. The best sensory properties were detected when examining the products with an addition of wheat and potato fibre. The enrichment of bread with fibre at 1% or 3% increased the dietary fibre content in bread with slightly adverse effects on bread quality.

The aim of this research was to determine the influence of the process parameters and pre-treatment methods on the quality and drying kinetics of apple samples of the Florina variety using standard analytical methods: thermo-gravimetry, rehydration, colorimetry. The Apple samples were dried in a laboratory tray drier at different temperatures (50, 60, and 70°C), airflow velocities (1.5 m/s and 2.75 m/s), and pre-treatment methods (dipping in 0.5% ascorbic acid solution; 0.3% L-cysteine solution; 0.1% 4-hexyl resorcinol solution; 0.5% sodium metabisulfite solution; mixed solution of 0.05% 4-hexyl resorcinol and 0.5% sodium metabisulfite; blanching in hot water at 85°C). According to the drying time, rehydration and colour characteristics, the optimal drying parameters found were: temperature of 60°C and airflow velocity of 2.75 m/s. The drying kinetic equations were estimated using Page's mathematical model. The results of the estimation showed a good agreement with the experimental data. The best results were achieved when the samples were pre-treated with 4-hexyl resorcinol. Blanching in hot water resulted in a higher drying rate and higher rehydration ratio, but also in unacceptable changes in the colour appearance of the apple samples.

Abstract: The aim of this study was to analyse the production of gluten-free, low protein cookies, which can easily be consumed by celiac and phenylketonuria (PKU) patients. The formula was adopted to prepare the control cookies (without dried fruits) from maise starch, stabilisers, salt, sodium bicarbonate, protein-reduced milk powder, and sunflower oil. Different cookies were made by adding raisins (R), dried black currants (Cu), dried dates (D), dried apples and cinnamon (A) separately. In cookies, two different stabilisers were calculated according to starch weight [pectin (P): 0.15%, glycerol monostearate (GMS, G): 0.4%]. The effects of stabilisers and dried fruits on the physicochemical and sensory properties of cookies were investigated. The protein content was significantly higher (P < 0.05) in the cookies including R with pectin (PR), Cu with pectin (PCu), and A with pectin (PA). The amount of phenylalanine (Phe) was significantly higher (P < 0.05) in PR. The values of dietary fibre were the highest in the A cookies, while the lowest values appeared in the control (C). In the sensory evaluation (appearance, tasting properties, and affordability), it was found that PD (pectin with dries dates) was chosen as the best cookie (P < 0.05).

The paper describes the preparation and evaluation of phenolic extracts from waste materials - pomace (grape marc), seeds and press oil cake of the white grape variety Irsai Oliver (Vitis vinifera L.) and their addition to apple and grape juices to increase the nutritional properties. The waste samples were extracted using 50 or 80% ethanol (v/v). Some of the samples were extracted for 60 min at boiling temperature under reflux; the remainder were processed for 24 h on a shaker at room temperature. The highest antioxidant capacity (as measured using DPPH (758 ± 28 mM Trolox/kg of extracted matter)) and content of total polyphenols (74 ± 0.7 g gallic acid/kg of extracted matter) were found in the extract of the seeds obtained through extraction using 50% ethanol (v/v) at boiling temperature for 60 minutes. The press oil cake extract obtained by means of 80% ethanol (v/v) at boiling temperature for 60 min was evaluated as the best for enriching the sensory quality of apple and grape juices. The addition of 1 g of freeze-dried press oil cake extract to 1 l of juice increased the antioxidant capacity and total polyphenol content two-fold

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.

Limiting or preventing the growth of undesirable microbial flora in food products is one of the main goals of food microbiology. A number of preservation methods have been designed to extend the shelf-life of the food products by reducing the microbial growth while new antimicrobials are still examined. Monoglycerides are naturally occurring compounds with inhibitory activity against various microorganisms. We evaluate the antimicrobial effects of 8 monoglycerides in vitro and in fresh unpasteurised apple juice. Out of all monoglycerides tested, monocaprin (MAG C10:0) and monolaurin (MAG C12:0) showed the best ability to supress or prevent the growth of filamentous fungi in vitro. The addition of these monoglycerides to apple juice resulted in a decrease in total viable counts of bacteria and yeasts. Monocaprin was able to stop completely the growth of bacteria and yeasts at a concentration of 250 µg/ml, and to prevent microbial spoilage of apple juices for at least two weeks.

Eight less-known juices are characterised and contents are monitored of selected substances and nutritional parameters. 100% juices were produced of Aloe Vera, Aronia, Blackcurrant, Black elder, Cranberry, Malpighia, Pomegranate and Seaberry by pressing, including the flesh. Total phenolic compounds (TPC) and ascorbic acid (AA) content were analysed as other parameters. The juices were measured on total antioxidant capacity (TAC) as the content of trolox, where the highest levels were found for Malpighia 63.2 mM, when the value was significantly different (P < 0.05) compared with all the other juices, while Aloe Vera had lowest levels with 0.4 mM. The Aronia juice possessed the highest level of TPC (8297 mg of GAE/l). TAC levels very well corresponded with TPC levels while AA content actually did not correlate with TAC values. In addition to the objective analysis, the juices were subjected to a sensory evaluation. Blackcurrant presents an attractive product from the sensorial aspect as well as in terms of the nutritional value.

This work aimed to determine if it was possible to eliminate or reduce the content of the Api g1 allergen in celery juice by oxidation, utilising its natural polyphenol oxidase (PPO) content. We attempted to determine a possible relationship between the enzymatic browning of celery juice and the reactivity of the Api g1 allergen. Pressed celery juice was stirred, and samples for the colour measurement and allergenicity, determined using the Western Blot (WB) method, were collected at pre-defined times. Oxidation failed to eliminate the allergenicity of pure celery juice. Further trials were focused on celery allergen elimination in apple-celery juices mixtures in ratios of 3:1, 5:1, and 7:1. We selected the 5:1 ratio as the most acceptable from the sensory perspective, and monitored its allergenicity using the WB method, basophil activation test, and skin prick testing. The WB test showed that oxidation, caused by stirring for 120 min, reduced the allergenicity of the mixture. However, the basophil activation test showed no reduction in the allergic response to the oxidised juice mixture. Skin testing showed that the oxidised juice mixture stirred for 120 min exhibited a significantly lower reaction than the juice mixture stirred for 60 min or celery and apple juice stabilised with ascorbic acid. Due to the contradictory results in different tests, the method cannot be declared successful or safe, even for mixtures of apple-celery juices.

The textural characteristics of onion slices (Allium cepa L.) of 3- and 7-mm thicknesses undergoing convective drying (50, 60, and 70°C) and microwave drying (68, 204, and 340 W real effective power levels) techniques with or without pre-treatment were evaluated. Pre-treatment consisted of dipping into brine solution (8% NaCl). Texture profile analysis at 25% compression was applied and hardness, chewiness, springiness and gumminess values of onions were recorded. As the temperature (convective) or real effective power level (microwave) increased, the hardness and chewiness levels of dried onion slices were enhanced. The values of these parameters were higher in response to microwave application compared to convective drying. Pre-treatment had an additive effect on hardness and chewiness in convectively dried samples. Maximum springiness was observed in response to convective drying. Dipping in brine solution generally caused no significant changes among slices of the same thickness (P < 0.05). With respect to gumminess, the results were quite similar to those for hardness and chewiness, i.e., markedly higher in microwave-dried onions.

Different solvents and extraction solutions (distilled water, NaCl, Tween 80, citrate buffer, and acetate buffer) were evaluated for enzymes recovery. The independent variables evaluated were agitation (12-348 rpm), time (4.8-55.2 min), and temperature (13.2-46.8°C) and 10 extraction cycles, using an experimental design (Central composite rotatable design 2³). Pectin methyl esterase maximum recovery by solid state culture of Aspergillus niger was 11 U/g_wm (31 U/g_dm) using NaCl (0.1 mol/l) as solvent at a 5 : 1 (v/w) ratio, 30°C for 55.2 min, at 180 rpm, with one extraction cycle.

DNA extraction is a crucial step in PCR analysis especially when analysing food samples that can be degraded and can potentially contain PCR-inhibiting substances. In this study, we compared the suitability of three DNA extraction methods - two kits: DNeasy^® Plant Mini Kit and NucleoSpin^® Food, and the CTAB method - for DNA extraction from commercial fruit jams. Fourteen jams with different contents of fruit, sugar and other additives were extracted in triplicate using the above-mentioned methods directly and after a washing step. The concentration and optical density were analysed using UV spectrophotometry and the amplifiability of the obtained DNA was evaluated using a PCR assay targeting a sequence coding for chloroplast tRNA-Leu. Samples isolated using the NucleoSpin^® Food kit contained non-amplifiable DNA in eight cases, and samples isolated using the CTAB method could not be quantified. The DNeasy^® Plant Mini Kit thus proved to be the most suitable method, since well-amplifiable DNA was obtained for all the analysed samples.

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.