Use of Carnobacterium spp protective culture in MAP packed Ricotta fresca cheese to control Pseudomonas spp.

Ricotta fresca is a whey cheese susceptible of secondary contamination, mainly from Pseudomonas spp. The extension of the shelf life of refrigerated ricotta fresca could be obtained using protective cultures inhibiting the growth of this spoilage microorganism. A commercial biopreservative, Lyofast CNBAL, comprising Carnobacterium spp was tested against Pseudomonas spp. The surface of ricotta fresca samples were inoculated either with Pseudomonas spp or Pseudomonas and Carnobacterium spp. Samples were MAP packed, stored at 4 °C and analyzed the day of the inoculum and 7, 14 and 21 days after the contamination. Microbiological analyses included total bacterial count, mesophilic lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp, Listeria monocytogenes, moulds and yeasts. Pseudomonas mean initial contamination level was comparable in blank and artificially inoculated samples, respectively with values of 2.15 ±â€¯0.21 and 2.34 ±â€¯0.26 log cfu g-1. Carnobacterium spp. significantly reduced the growth of Pseudomonas spp respectively of 1.28 log and 0.83 log after 14 and 21 days of refrigerated storage. Intrinsic properties and physico-chemical composition were also investigated. Limited variation of pH was observed in samples inoculated with the protective cultures, indicating low acidification properties of Carnobacterium spp. Instead, no significant differences were observed for aW, moisture, fat and proteins during storage and between inoculated and control samples.

Testing commercial biopreservative against spoilage microorganisms in MAP packed Ricotta fresca cheese.

Ricotta fresca cheese is susceptible to secondary contamination and is able to support the growth of pathogens or spoilage psychotrophic bacteria during storage. The aim of the present study was to evaluate which among three commercial biopreservatives was suitable to be used to control the growth of spoilage microorganisms in sheep's milk MAP ricotta fresca cheese. 144 Ricotta fresca cheese samples were inoculated either with the bioprotective culture Lyofast FPR 2 (including Enterococcus faecium, Lactobacillus plantarum e Lactobacillus rhamnosus) or Lyofast CNBAL (Carnobacterium spp) or the fermentate MicroGARD 430. Not inoculated control and experimental ricotta were MAP packed (30% CO2 and 70% N2) and stored at 4 °C. Triplicate samples were analyzed after 5 h and 7, 14 and 21 days after inoculation for total bacterial count, mesophilic lactic acid bacteria, Enterobacteriaceae, Pseudomonas spp, Listeria monocytogenes, moulds and yeasts. Among the tested biopreservatives only Carnobacterium spp was able to control Pseudomonas spp and Enterobacteriaceae. The maximum reduction in the concentration of Pseudomonas spp and Enterobacteriaceae was respectively 1.93 and 2.66 log10 cfu/g, observed 14 days after production. Therefore, Carnobacterium spp was selected as the culture of choice to conduct a challenge study against Pseudomonas spp.

A novel method for the determination of ascorbic acid and antioxidant capacity in Opuntia ficus indica using in vivo microdialysis.

A simple and rapid method was developed for in vivo simultaneous determination of ascorbic-acid and antioxidant capacity in microdialysates from cladodes of Opuntia ficus-indica (L.) Miller. The method is verified in water-stressed plants, as compared with a well-watered test controls. The microdialysis probe construction and insertion procedure was specifically developed to minimise the tissue trauma of the plant and to obtain optimal dialysis performance. Microdialysis was performed using a flow rate of 3 µL/min and the samples were analysed by HPLC coupled to electrochemical detection of ascorbic-acid and DPPH-determined antioxidant capacity. Our data indicate exponential decay of the concentrations of the analysed compounds as a function of microdialysis sampling time. Water-stressed Opuntia show decreased ascorbic acid levels and increased the others antioxidants.

Vegetable and animal food sorts found in the gastric content of Sardinian Wild Boar (Sus scrofa meridionalis).

Authors report results emerging from gastric content analysis from n. 96 wild boars hunted in Sardinia isle, during the hunting tide (2001-2005), from November to January. Mean pH of the gastric content was 3.77 +/- 0.69. Mean total capacity (TC) of each stomach was 1702 +/- 680 g. Mean Stuff ratio (CW/TC) between the content weight (CW) and stomachs TC was 0.45. Food categories found in animal stomachs were: 19 categories of vegetal species (Allium spp., Arbutus unedo, Arisarum vulgare, Avena fatua, Avena sativa, Castanea sativa, Ceratonia siliqua, Chamaerops umilis, Cichorium intybus, Hordeum sativum, Juniperus oxycedrus, Myrtus communis, Olea europea, Pirus amygdaliformis, Pistacia lentiscus, Quercus spp., Rhamnus alaternus, Triticum durum, Zea mais); 11 categories of animal species (Agriotes lineatus, Apodemus sylvaticus dicrurus, Chalcides chalcides, Chalcides ocellatus tiligugu, Crematogaster scutellaris, Forficula auricularia, Helix aspersa, Lumbricus terrestris, Ovis aries, Podarcis tiliguerta tiliguerta, Scolopendra cingulata); three categories were identified in general terms (insects larvae, hairs of mammals, feathers of birds). Food categories found in the stomach contents of Sus scrofa meridionalis confirm observations by other researchers who report the prevalence of vegetables in spite of animal food sorts in the wild boar diet in Italian regions.

Ileocecal valve imaging on computed tomographic colonography.

BACKGROUND: The aim of our study was to describe the visualization, normal anatomy, and variations of the ileocecal valve with computed tomographic (CT) colonography to provide information about its optimal imaging. METHODS: We analyzed data in two- and three-dimensional rendering mode in 71 consecutive patients who underwent routine CT colonoscopy followed by conventional colonoscopy for confirmation of the radiologic findings. RESULTS: Complete visualization of the ileocecal valve was better achieved in the supine than in the prone position (82% vs. 62%, respectively); the ileocecal valve appeared in 64% of cases in the supine position when it was invisible in prone position (p < 0.0001). Partial visualization of the ileocecal valve was possible in 94% of cases. The ileocecal valve was of labial type in 76%, papillary type in 21%, and lipomatous in 3% of cases. The orifice was identified in 53% of ileocecal valves; in two cases of cecal carcinoma, the normal ileocecal valve morphology was grossly disrupted. CONCLUSION: The ileocecal valve was at least partly visualized by CT colonoscopy in 94% of cases, more frequently in the supine position. Its most common normal morphology is the labial type. The absence of orifice visualization alone is not a specific sign for neoplasia, but its presence helps distinguish physiologic bulging from neoplasia.

Polyamine levels during the onset of "CAM" inOpuntia F. indica (Miller).

Polyamines have been related to the "Crassulacean Acid Metabolism" (CAM) in higher plants. Such relationship was however observed in plants where CAM activity is inducible by external factors. Results presented here indicate that, inOpuntia F. indica, cladodes where onset of CAM is dependent on internal conditions, i.e. leaf age, the concentration of putrescine increases in parallel to the acidity of the cytoplasm. The parallel increase of putrescine concentration and acidity (malic acid concentration) can be best evaluated during the onset of CAM (young cladodes), while such correlation is not observed in mature cladodes where CAM is already in it's full function. Spermidine and spermine show no correlation with CAM activity neither during the onset of CAM nor during it's full function. However, spermidine levels correlate negatively to CAM activity when cladodes attain > 30 days of age. The results suggest that putrescine in free form could possibly counteract the increase of cellular acidity during onset of CAM inOpuntia F. indica; the possible roles of spermidine are discussed.