Reduction of Salmonella enterica serovar enteritidis on the surface of raw shelled almonds by exposure to steam

This study was conducted to investigate the effect of steam treatment on the reduction of Salmonella enterica serovar Enteritidis on the surface of raw almonds. Two cultivars, 'Nonpareil' and 'Mission', were studied. Salmonella Enteritidis was inoculated on the surface of raw almonds, which were then treated with steam (93 degrees C +/- 1 degrees C) for 5, 15, 25, 35, 45, 55, and 65 s. After steam treatment, samples were plated on xylose lysine desoxycholate (XLD) and overlay (OV) XLD as a selective and nonselective agar for Salmonella, respectively, to investigate the extent of sublethal injury in Salmonella. Steam treatment of raw almonds effectively reduced Salmonella Enteritidis, and the effect was pronounced with increasing treatment time. After 65 s of steam treatment, reductions in Salmonella Enteritidis populations were 5.7 log and 5.8 log for 'Nonpareil' and 4.0 log and 4.1 log for 'Mission' when enumerated on XLD and OV XLD, respectively. There was no significant difference in population estimates determined with XLD and OV XLD over time (P > 0.05). The effect of the steam treatment was significantly different between two almond cultivars. Salmonella inoculated onto 'Mission' was more resistant to the steam treatment than that on 'Nonpareil', indicating that varietal differences must be considered in the application of steam for the disinfection of raw almonds. The present investigation revealed the potential usefulness of steam treatments for the control of pathogens in raw almonds.     

In vitro and in vivo antioxidant activity of musts and skin extracts from off-vine dried Vitis vinifera cv. “Tempranillo” grapes

The phenolic composition and antioxidant activity of musts and skin extracts from Tempranillo grapes dried for variable lengths of times were examined here. Both were found to increase in the grape must with increasing drying time, but the opposite trend was observed in the skin extracts. The antioxidant activity of the must and skin was largely due to anthocyanins. Also, the anthocyanins fraction exhibited the highest antioxidant activity per gram of phenolic compound in the musts and skin extracts at the end of the drying process, polymeric pigments and high-molecular-weight procyanidins were also prominent in this respect. In vivo antioxidant activity in terms of protein oxidation and survival of Saccharomyces cerevisiae cells previously incubated with 10 μg/mL of polyphenols from the musts and skins and exposed to hydrogen peroxide was also measured. Both extracts exerted a protective effect against oxidative stress, the effect increasing with increasing dehydration time and being somewhat higher for skin than for must. Thus, must and skin from dehydrated grapes possess antioxidant properties, which allow the latter, a by-product of sweet wine, to be used as a natural source of antioxidants.     

Protective effects of phenolic constituents from Cytisus multiflorus,Lamium album L. and Thymus citriodorus on liver cells

The present study investigated the antioxidant and cytoprotective effects of purified ethanolic extracts of Cytisus multiflorus, Lamium album L. and Thymus citriodorus plants. These extracts showed high antioxidant activity in DPPH and reducing power assays. Using a model of chemical stress induced by potassium dichromate (DK) in human hepatoblastoma HepG2 cells, 50 μg/mL of C. multiflorus, L. album and T. citriodorus extracts decreased the rate of reactive oxygen species (ROS) production by 35%, 26% and 20%, respectively, when exposed to 25 μM of DK. This effect was also observed for the treatment of cells with individual polyphenolic compounds determined in the extracts, or with mixtures prepared with individual polyphenolic compounds simulating the phenolic composition of the extracts. Additionally, the purified ethanolic extracts and the prepared polyphenolic mixtures showed a cytoprotective effect against DK-induced toxicity. The overall results emphasize the contribution of polyphenols in antioxidant and cytoprotective properties of the studied plants.     

Influence of air temperature on drying kinetics and antioxidant potential of olive pomace

This work aims to evaluate the influence of olive pomace drying (a solid by-product of the olive oil industry) on both antioxidant potential and drying kinetics. The two main fractions of olive pomace (pits, PI and pulps + peels, P + P) were characterized by image analysis and density measurement. The drying process was analyzed in experiments carried out at different temperatures (from 50 to 150 °C) and mathematically described from the diffusion and Weibull models. The antioxidant potential of the extracts (ethanol–water 80:20 v/v, 22 ± 1 °C, 170 rpm for 24 h) obtained from the dry product was analyzed by measuring the total phenolic content and antioxidant capacity and the main polyphenols were quantified by HPLC–DAD/MS–MS.     

Geographical origin classification of olive oils by PTR-MS

The volatile compositions of 192 olive oil samples from five different European countries were investigated by PTR-MS sample headspace analysis. The mass spectra of all samples showed many masses with high abundances, indicating the complex VOC composition of olive oil. Three different PLS-DA models were fitted to the data to classify samples into ‘country’, ‘region’ and ‘district’ of origin, respectively. Correct classification rates were assessed by cross-validation. The first fitted model produced an 86% success rate in classifying the samples into their country of origin. The second model, which was fitted to the Italian oils only, also demonstrated satisfactory results, with 74% of samples successfully classified into region of origin. The third model, classifying the Italian samples into district of origin, yielded a success rate of only 52%. This lower success rate might be due to either the small class set, or to genuine similarities between olive oil VOC compositions on this tight scale.     

Potentiality of Indian pineapple leaf fiber for apparels

The use of textile-grade fiber extracted from the Indian pineapple leaf is an unexplored area. Pineapple leaf fiber (PALF) is fine, soft, and moderately strong and is much acceptable for fashion garment. An attempt has been made to extract and soften Indian PALF from the pineapple leaves by decortication and subsequent water retting. Decorticated cum retted fiber has shown better physicomechanical and surface appearance properties than decorticated fiber. Fine yarn (38 tex) was spun in a suitable spinning system, and the property performance was found to be suitable to make eco-sustainable novelty fabric. Fabric was developed by using cotton as warp yarn and PALF-based yarn as weft in a handloom. The developed fabric shows very good physical and mechanical properties, desired for apparels. This inferred that Indian PALF may be successfully used to make eco-niche apparel quality fabric as well as novelty textiles.     

Atmospheric DMSO degradation in the gas phase: Cl-DMSO reaction. Temperature dependence and products

The reactions of Cl atoms and ClO radicals with CH3-SOCH3 (DMSO) have been studied using the discharge flow method with direct detection of DMSO, CO, and products by mass spectrometry. The absolute rate constant at room temperature measured for reaction 1, (CH3)2SO + Cl --> products, was k(1) = (1.7 +/- 0.3) x 10(-11) cm3 molecule(-1) s(-1). For reaction 2, (CH3)2SO + ClO --> products, only an upper limit could be established, k(2) < or = 6 x 10(-14) cm3 molecule(-1) s(-1) Reaction 1 has been found to proceed through adduct formation and further decomposition involving the cleavage of the C-S bound. The pressure effect on the Cl-DMSO reaction from 0.5 to 3 Torr was negligible, and the temperature dependence in the range 273-335 K was also very slight. The results obtained are related to previous studies of sulfur compounds, and the atmospheric implications are also discussed in relation to the homogeneous sinks of DMSO. Tropospheric lifetimes of DMSO based on average Cl and ClO concentrations and the measured rate constants have been calculated showing that the contribution of reaction 1 must be of minor relevance in the marine boundary layer. Reaction 2 is so slow that it does not play any role within the atmospheric sulfur chemistry.     

Variation in Malting Quality and Heat Resistance in the Malting Barley Variety “Alexis”

In earlier studies concerning vigour, where subsamples are heat‐treated before germination there was found heat‐sensitive as well as heat‐resistant barley samples. The vigour model developed by Ellis and Roberts and further developed at Carlsberg, could only describe the heat‐sensitive barleys. Seventeen samples of the “Alexis” variety grown widely in Europe were collected from the EBC trials in 1994 in order to see if heat resistance in barley was influenced by different growing conditions. We found both heat‐sensitive samples following the vigour model as well as pronounced heat‐resistant samples, but these were not divided according to growing conditions. The germination curves dependent on heat treatment and germination time were evaluated by Principal Component Analysis (PCA). Heat‐resistant barley samples could be differentiated from heat‐sensitive samples already after ½ h of heat treatment at 68°C (12% moisture) and after 3 days of germination. The barley samples were analysed with regard to malting quality. The PCA evaluation of the data divided the samples according to growing location, mainly due to differences in protein and β‐glucan. However, the malting analyses could not describe the differences in heat resistance and sensitivity of the barleys. The biochemical background of the heat resistance found is discussed on the basis of literature. Our findings should give an experimental basis for exploiting a biochemical principle for heat resistance, which is formed during grain filling and consumed during storage and germination.     

Modified atmosphere packaging of filleted rainbow trout

Shelf‐lives of filleted rainbow trout (Oncorhynchus mykiss) packaged in over‐wrap, vacuum and gas mixture conditions and stored at 1 ± 1 °C were compared by measurement of pH, total volatile bases (TVB), hypoxanthine content, lipid oxidation (TBARS value), superficial counts of aerobic psychrotrophic flora and sensory analysis (colour, odour and flavour). The gas mixtures evaluated were 10% O₂ + 50% CO₂ + 40% N₂, 10% O₂ + 50% CO₂ + 40% Ar, 20% O₂ + 50% CO₂ + 30% N₂, 20% O₂ + 50% CO₂ + 30% Ar, 30% O₂ + 50% CO₂ + 20% N₂ and 30% O₂ + 50% CO₂ + 20% Ar. Sensory quality deterioration was delayed and bacterial growth as well as increases in pH, TVB and hypoxanthine levels were reduced by modified atmosphere packaging (MAP). Lipid oxidation was higher in gas packages with 20 and 30% O₂ than in those with 10% O₂. Vacuum‐packed fillets presented the lowest TBARS values. In summary, MAP gave rise to a significant extension of shelf‐life when compared with vacuum and over‐wrap packaging. No significant differences were found between the packages containing either N₂ or Ar. The best evaluated atmosphere consisted of 10% O₂ + 50%CO₂ + 40% N₂/Ar. © 2002 Society of Chemical Industry