Search

Vacuum impregnation (VI) allows soluble solids to be introduced into the porous matrix of a food material, modifying the composition of the tissue to facilitate further processing. The purpose of this research was to analyze the influence of pressure on the effectiveness of VI on a low porous material that is difficult to impregnate. Two cultivars of carrot (Baltimore F1 and Komarno) were subjected to VI at 5 and 30 kPa in a ternary solution of ascorbic acid (0.5%), citric acid (0.5%), and sucrose (8%) under isotonic conditions. The products were analyzed in terms of ascorbic acid content, degree of impregnation, and changes in structure, texture, color, antioxidant activity, phenolic content, carotenoids, and structure-forming compounds. Increases in vitamin C content (after VI) depended on the process conditions and ranged from 900% to 1300% in relation to the raw material. It was also observed that the extended impregnation time at a pressure of 5 kPa produced slices that were also impregnated in parenchyma area. The increased levels of polyphenolic compounds found in the saturated product may suggest that de novo synthesis under the influence of physiological stress had occurred. [ABSTRACT FROM AUTHOR]

Increasing the consumption of fruit and vegetables can be achieved by creating new products. A promising method seems to be the directed fermentation of vegetables. The aim of this study was to investigate the effect of ultrasonic pretreatment (US; 25 kHz; 5 min) and the lactic acid bacteria strain (LAB; Lactiplantibacillus plantarum 299v and Lacticaseibacillus rhamnosus GG) on the quality of fermented pumpkin (Cucurbita pepo L.). The pumpkin was inoculated with 5 log CFU/g of specific LAB strain. Fermentation was carried out for 7 days at 35 °C. Some samples were US treated at the washing stage. During fermentation, there was an increase in the LAB count of 3 logarithmic cycles compared to the initial inoculum. For L. rhamnosus, preceding fermentation by US treatment contributed to an increased bacteria count of 4 logarithmic cycles. In the case of fermentation with L. rhamnosus, the lactic acid content was significantly higher than for L. plantarum. These samples are also characterized by higher sensory properties, desirability of taste, and overall desirability. Fermentation contributed to a decrease in carotenoid and phenolic compounds content and an increase in the antioxidant capacity of the pumpkins, regardless of the bacterial strain. [ABSTRACT FROM AUTHOR]

AbstractThe study’s purpose was to assess ultrasound’s effectiveness in vacuum impregnating apples with ascorbic acid, and to evaluate the effects of drying conditions on ascorbic acid retention. Drying kinetics, water activity, and color of the dried products were also analyzed in relation to drying conditions. Ultrasound (35 kHz, 240 W) was used during individual impregnation phases (30 min) and also throughout the process (70 min). Drying was conducted using free and forced convection (2 m/s) at 40, 50, and 70 °C, and microwave-assisted forced convection (2.45 GHz, 100 W). It was found that ultrasound did not affect impregnation, as a similar content of ascorbic acid was observed in the products regardless of the ultrasound’s phase or duration. Drying conditions significantly influenced drying kinetics and ascorbic acid stability, with higher air temperatures accelerating drying but reducing ascorbic acid content. Excessive ultrasound exposure during impregnation further decreased ascorbic acid content. The most successful method was impregnation under forced convection drying at 50 °C without ultrasound. [ABSTRACT FROM AUTHOR]

Okara and linseed cake are nutrient-rich by-products containing phytoestrogens, which are underutilized in food production. The aim of this study was to optimize hydrothermal treatment and fermentation time using common starters for tempeh fermentation. Changes in isoflavones and secoisolariciresinol diglucoside (SDG) were analyzed using the HPLC-PDA method. Okara and linseed cake were steamed for 5 to 40 min, followed by fermentation with Rhizopus oligosporus at 30 °C for 48 h. The optimal steaming times were 10 min for okara and 20 min for linseed cake. Isoflavone analysis revealed a change in total levels depending on the microflora, with a significant increase in aglycones during fermentation. SDG levels did not show a significant reduction. In 24-h fermented tempeh, the isoflavone acetylglycosides content increased after frying. These results suggest that steam treatment is an effective hydrothermal method, offering energy and water savings. Additionally, the ability to modulate isoflavone composition through fermentation creates new opportunities for pro-healthy food development. This study concludes that okara and linseed cake can be successfully used for tempeh production, providing a sustainable alternative to conventional tempeh substrates. By utilizing these by-products, this research promotes the reduction of food waste and supports the development of environmentally friendly food production practices. [ABSTRACT FROM AUTHOR]

The utilization of food industrial by-products, especially pomace after juice processing, could be a big challenge. Chokeberry pomace is a valuable source of phenolic compounds, including procyanidins and anthocyanins. These compounds have, e.g., antioxidant, anticancer, hypoglycemic, hypotensive, hepatoprotective and cardioprotective effects. In this work, dried chokeberry pomace (2.0 g, 2.5 g and 3.0 g) was added to green tea leaves or white or red hibiscus flowers (0.5 g of each) to obtain mixtures for preparing infusions. Such products could be a valuable source of bioactive compounds. After brewing and cooling, selected quality parameters of the obtained infusions were tested: pH, total phenolic content (TPC), anthocyanin content and the instrumentally and sensorily determined color. The composition of the infusion had an impact on the color. Those from a mixture of chokeberry by-products and hibiscus possessed lower L* and higher a* and b* values than those composed of chokeberry and green tea leaves. Infusions prepared from the mixture containing dried chokeberry pomace (3.0 g) and green tea leaves (0.5 g) had a higher content of anthocyanins (17%) and phenols (48%), respectively, than other samples with the same proportions of ingredients. According to PCA analysis, the highest content of the tested bioactive compounds was obtained in infusions of green tea leaves with the addition of chokeberry pomace. [ABSTRACT FROM AUTHOR]

Featured Application: An important aspect of food production is achieving high yield in the production process while striving to improve quality. The conducted research indicates the application potential of thermosonication used as a method of mash treatment, both in terms of increasing the efficiency of the pressing process and the content of anthocyanins and other phenolic compounds (an increase of 40% and 20%, respectively, compared to the juice obtained from the mash without treatment). In particular, the increased content of anthocyanins in the juice shows not only health-promoting potential but also affect the formation of the appropriate color of the product. Strawberries are rich in bioactive compounds that may be of health importance. The technological process often significantly reduces the content of such compounds in the product. The study aimed to compare the effect of enzymatic, ultrasonic and thermal mash treatment on the content of ascorbic acid, anthocyanins, phenolic compounds and the antioxidant activity of strawberry juice. In addition, the effect of increased temperature assisting ultrasonic mash treatment and the use of a vacuum for a short period to remove air from the mash during pectinolysis was investigated. A significant increase in the efficiency of juice pressing was obtained for enzymatic treatment (by 40%), thermal and thermosonication (16%). It was found that the applied methods yield different results depending on the tested compounds. In the case of anthocyanin, the most effective method was thermosonication, which contributed to a 40% increase in their content. The enzymatic and thermal methods resulted in a two-fold increase in the content of phenolic compounds. The antioxidant activity of the juice from the treated mash (regardless of the method used) was significantly higher than samples from the untreated mash. A significant correlation (r = 0.77) was noted between antioxidant capacity and non-anthocyanin phenolic compound content in the tested juices. [ABSTRACT FROM AUTHOR]

We investigated the changes in Nɛ-(carboxymethyl)lysine (CML) and available lysine content, antioxidant properties, volatiles, and oxidation products of biscuits enriched with grape by-product (GP), stored for six months under a modified atmosphere of 0%/30%/70% O2/CO2/N2 and in air. Fresh GP-formulated biscuits showed lower concentrations of CML (89%), available lysine (40%), and pyrazines (75%), but higher antioxidant capacities (~ sixfold), furans (12-fold), and lipid-derived compounds (three-fold) than the control. Although ~ 15% higher losses of Maillard-type volatiles were identified in the air atmosphere during storage, lipid oxidation was ~ 30% less pronounced in the modified atmosphere. A significant correlation of 0.994 between the reduction in CML and the available lysine suggest further CML reactions with the ɛ-NH2 group of amino acids. Significant correlations (of -0.550 to -0.980) between oxidation products, antioxidant capacities, and changes in CML content during storage suggest that these parameters might be involved in the CML elimination mechanism. [ABSTRACT FROM AUTHOR]

The minor lipophilic composition of seed oils obtained from two medicinal plants (C. capsularis and H. sabdariffa L.), tocopherol, tocotrienols, sterols, carotenoids and squalene, was studied. The oil yield from the seeds of H. sabdariffa and C. capsularis was 19.1 and 12.7%, respectively. The main three fatty acids of the oils from both species were – linoleic, oleic, and palmitic acid (over 95% of all). γ-Tocopherol consisted of over 65% of total tocopherol content of four detected homologues, in both species. Nine and ten sterols were detected in H. sabdariffa and C. capsularis seed oil, respectively. β-Sitosterol was the main sterol (over 50% of all). Lutein was the main carotenoid detected in both species. The total amount of tocopherols, carotenoids and sterols in C. capsularis vs. H. sabdariffa seed oil were 117.2 vs. 159.2, 0.27 vs. 0.74, and 247.1 vs. 968.0 mg/100 g oil, respectively. [ABSTRACT FROM AUTHOR]

Kernels recovered from fruit pits of 14 apricot (Prunus armeniaca L.) genotypes are tested for future application as feedstock for biodiesel production. The difference between the lowest and the highest oil yield between studied samples is over twofold and reached between 27.1 and 58.7% (w/w) dw. The oleic and linoleic acids are the two dominant fatty acids in apricot kernel oils; however, their content is affected meaningfully by the variety and amounted to 38.5–67.2 and 26.4–54.8%, respectively. Two significant correlations (p < 0.000005) are found between oil yield in kernels of different apricot genotypes and two fatty acids, oleic and linoleic (r = 0.947 and r = −0.927, respectively). The biodiesel parameters of 14 apricot genotypes are calculated empirically according to previously developed equations based on the fatty acid methyl esters composition of the potential feedstock. The European biodiesel standards of kinematic viscosity, cetane number, density, and iodine value are met for 13 investigated samples. The exception was noted for genotype HL PSŠ 5. The recorded differences between minimum and maximum value of individual biodiesel parameters calculated empirically for various apricot genotypes differed as follows: 0.20 mm2 s−1 (kinematic viscosity), 4.9 (cetane number), 0.06 MJ kg−1 (higher heating value), 0.0028 g cm−3 (density), 15.6 I2/100 g (iodine value), 1.67 °C (CFPP), and 2.15 h (induction period). The logarithmic regression model in comparison to linear regression model, better expressed the relationship between physicochemical properties of biofuel and the ΣPUFA/(ΣSFA + ΣMUFA) ratio. To confirm the usefulness of the applied empirical equations for biodiesel parameters prediction of the apricot feedstock, five cold‐pressed apricot kernel oils of different origin and with a varied composition of fatty acids are tested experimentally and compared with the values calculated empirically. Practical Applications: Apricot kernels have limited use in food industry due to a high content of the amygdalin. Therefore, application of apricot kernels as potential feedstock for the biodiesel production seems to be reasonable, especially due rich oil yield (up to even 60%). In this paper the impact of the apricot genotype on the potential application in the biodiesel industry as well as the relationship between the oil yield and apricot biodiesel quality is described. Obtained biodiesel parameters of 14 apricot (Prunus armeniaca L.) genotype oils can help estimate the economic perspectives of utilization as a potential energy source. The present study may contribute to the more targeted use of the apricot (Prunus armeniaca L.) kernels and promotes the efficient management of the plant material and environmental sustainability. Kernels recovered from fruit pits of 14 apricot (Prunus armeniaca L.) genotypes are tested for future application as feedstock for biodiesel production. High oil yield 27–58.7% (w/w) dw and predomination of the oleic and linoleic acids 38.5–67.2 and 26.4–54.8%, respectively, is recorded in the tested genotypes. The European biodiesel standards of kinematic viscosity, cetane number, density, and iodine value are met for all investigated samples, with the exception of genotype HL PSŠ 5. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of soaking in ascorbic acid and citric acid solution and modified atmosphere packaging on the quality of a coleslaw mix stored for 12 days at 4C. Pretreatment caused a reduction by ∼2 logarithmic cycles for counts of psychrophilic bacteria from the genus Pseudomonas, and mesophilic yeasts, as well as a significant decrease in the counts of mesophilic bacteria and coliform bacteria. Packaging of tested samples in modified atmosphere with high contents of oxygen (70 or 50%) and carbon dioxide (30%) caused an inhibition of growth for mesophilic, psychrophilic, lactic acid and coliform bacteria during storage. Application of atmosphere with increased contents of CO2 (25 or 30%) resulted in the inhibition of growth of bacteria from the genus Pseudomonas, while in the case of elevated (70%) or reduced contents of oxygen (5%) a slower growth of yeasts was observed. Practical Application The using of the atmosphere with a high content of oxygen is the new trend in the minimal processing of fruits and vegetables. When applying atmosphere with a high oxygen content in packaging of fruit and vegetables it is recommended to use barrier films, which guarantees maintenance of high contents of this gas during product storage. In the case of coleslaw mix, sensory quality (particularly aroma) is not acceptable. Using pretreatment (soaking in ascorbic acid (5 g/L) and citric acid (5 g/L) solution) and atmosphere of 70% O2 and 30% CO2 with microperforated barrier film results in good sensory and microbiological quality (regarding to research parameters) of the coleslaw mix during 12 days of storage. [ABSTRACT FROM AUTHOR]

Copyright of Science, Nature, Technologies / Nauka, Przyroda, Technologie is the property of Science Nature Technologies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The regulation of phenotypes of vegetable-associated bacteria can be mediated through the production of acylated homoserine lactones (AHLs). This knowledge is essential for successful control of bacterial diseases of vegetable. The purpose of these investigations was to define the AHL patterns of gram-negative bacteria presented in storage cabbage by LC/MS technique. The phenomenon of regulating the pectinolytic activity and the exopolysaccharide (EPS) production by AHLs that are associated with microbial spoilage of cabbage was also examined. Among 100 strains isolated from storage cabbage, 47 isolates produced AHLs. The results of the 16S rDNA sequence analysis indicated that selected microflora was highly closely related to Pantoea agglomerans, Rahnella aquatilis, Pseudomonas fluorescens, Pseudomonas syringae, and Pseudomonas cedrina (approximately 98%-99% confidence). The chemical nature of AHLs produced by selected microflora differ from species to species. The pattern of AHLs of Ps. cedrina consisting of C8- HSL, 3-oxo-C10-HSL, and 3-hydroxy-C14-HSL, has not been previously reported. The present study demonstrates that bacterial spoilage of storage cabbage is influenced by quorum sensing. Application of furanone C-30 that acts as quorum sensing inhibitor, caused the significant reduction in the production of EPS and pectinolytic enzymes by examined bacteria. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this study was to determine the effect of washing (4 °C, 120 s) or soaking (4 °C, 600 s) of shredded celeriac in tap water on changes in contents of phenolic compounds, including furanocoumarins, and sensory and microbiological quality during 12 days of storage. The product was packaged in air or modified atmosphere containing 2/10/88 kPa O2/ CO2/ N2. RESULTS The applied pre-treatment consisting of washing or soaking of shredded celeriac in water resulted in decreases in 8-methoxypsoralen content by approximately 50 and 70% respectively and phenolic content by 30% compared with samples that were not subjected to pre-treatment. During storage of shredded celeriac, a further significant ( P ≤ 0.05) reduction in phenolic compounds and an approximately 2.5-fold increase in the total content of furanocoumarins were found. The application of modified atmosphere packaging had a significant effect on the maintenance of good sensory and microbiological quality of the tested product. CONCLUSION Modified atmosphere packaging of shredded celeriac not subjected to pre-treatment made it possible to obtain a product with good sensory and microbiological quality and the highest content of phenolic compounds. The level of furanocoumarins recorded in the tested product does not constitute a health hazard. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the effect of different compositions of modified atmospheres and packaging film's microperforation density on changes in the levels of phenolic compounds and antioxidant capacity in a coleslaw mix stored for 12 days at 4°C. The salad was made up of 80% shredded head cabbage cv. Galaxy F1 and 20% carrot cv. Perfekcja. The samples were packaged in modified atmospheres with the following concentration (%) of O2/CO2 /N2 : 20/25/55, 50/30/20 and 70/30/0, as well as in normal air. Trays with samples of the prepared mix were sealed with a packaging film with oxygen permeability of 2500 cm³/m²/24h* bar. The film was microperforated using one (1x10) or two (2x10) cylinders 7 cm in diameter with 10 needles 70 µm in diameter. The levels of total and free phenols in the product, and the product's antioxidant capacity were determined after 0, 9 and 12 days of storage. After 12 days of storage, the total phenolic content and the antioxidant capacity of the tested samples were significantly higher than those of the fresh salad. In the case of free phenolic compounds, their level was significantly lower than in the salad before storage. The salad samples packaged in the film with 2x10 microperforations contained higher levels of total phenols and had a higher antioxidant capacity than the samples sealed with the film with 1x10 microperforations. [ABSTRACT FROM AUTHOR]

Background. Pumpkin seed oil is valuable oil for its distinctive taste and aroma, as well as supposed healthpromoting properties. The aim of this study was to investigate how roasting pumpkin seeds influences the physicochemical properties of cold-pressed oils. Materials and methods. The fatty acid composition, content of phytosterols, carotenoids and tocopherols, oxidative stability and colour were determined in oils after cold pressing and storage for 3 months using GC-FID, GCxGC-ToFMS, HPLC, Rancimat and spectrophotometric methods. Results. The results of this study indicate that the seed-roasting and storage process have no effect on the fatty acid composition of pumpkin seed oils, but does affect phytosterols and tocopherols. The carotenoid content decreased after storage. The colour of the roasted oil was darker and changed significantly during storage. Conclusion. Pumpkin oil obtained from roasted seeds shows better physicochemical properties and oxidative stability than oil from unroasted seeds. [ABSTRACT FROM AUTHOR]