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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]

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]

BACKGROUND Knowledge regarding microaerophilic and anaerobic specific spoilage organisms (SSOs) is crucial for an appropriate evaluation of vacuum-packed ham. The objective of this study was to characterize the SSO community in vacuum-packed ham by a culture-dependent technique and MiSeq next-generation sequencing (NGS) platform. The relation between changes among the SSO group in the ham and changes in sensory characteristics of the product was also assessed. RESULTS In the study, conventional microbiological analyses were employed in order to establish the participation of several groups of microorganisms in the deterioration of vacuum-packed ham. The diversity of the SSO group in the product was further assessed with the use of MiSeq NGS technology. The bacteria identified in sliced cooked ham belonged mostly to four phyla, namely Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. A temperature of 4 °C favoured the development of mesophilic and psychrophilic/psychrotrophic flora, mainly Lactobacillaceae, Enterobacteriaceae and Micrococcaceae families. A high ratio of Brochothrix thermosphacta species and new, cold-tolerant Clostridium spp. was also observed. The growth of these microorganisms facilitated changes in the pH value and organoleptic characteristics of the product. CONCLUSION This study confirms that the combination of culturing and MiSeq NGS technology improves the microbial evaluation of food. © 2016 Society of Chemical Industry [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]

Experiments focused on evaluating the ability of three aquatic plant species (sweet flag, common reed, and broadleaf cattail) to decontaminate industrial wastewater effluents from a nitroglycerin and nitroglycol production factory were carried out in the framework of this study. Toxicity of a nitrate-rich wastewater toward the studied plant species was determined by measurement of plant biomass gain, and subsequent mathematical modeling allowed for assessment of IC50 values. The studied plant species were cultivated in hydroponic cultures containing 1,500 mg/l of nitrates, 2.4 mg/l of nitroglycerin, and 1.0 mg/l of nitroglycol for 21 days, during which the decontamination efficiency of each nitrogen-based compound was analyzed. It was observed that the application of sweet flag and common reed contributed to a high nitrate removal efficiency (82 and 79%, accordingly). Sweet flag also was most efficient for decontamination of nitroglycerin (87%) and nitroglycol (42%), but the removal of the former compound was preferential. [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]