Wine industry residues extracts as natural antioxidants in raw and cooked chicken meat during frozen storage

The effect of Isabel (IGE) and Niagara (NGE) grape seed and peel extracts on lipid oxidation, instrumental colour, pH and sensory properties of raw and cooked processed chicken meat stored at -18 degrees C for nine months was evaluated. The pH of raw and cooked samples was not affected by the addition of grape extracts. IGE and NGE were effective in inhibiting the lipid oxidation of raw and cooked chicken meat, with results comparable to synthetic antioxidants. The extracts caused alterations in colour, as evidenced by the instrumental (darkening and lower intensity of red and yellow colour) and sensory results of cooked samples. In the sensory evaluation of odour and flavour, IGE produced satisfactory results, which did not differ from synthetic antioxidants. These findings suggest that the ICE and NGE are effective in retarding lipid oxidation of raw and cooked chicken meat during frozen storage. (c) 2011 Elsevier Ltd. All rights reserved.

Phenolic compounds and antioxidant activity of seed and skin extracts of red grape (Vitis vinifera and Vitis labrusca) pomace from Brazilian winemaking

The phenolic compounds content and antioxidant activity of seed and skin of pomace from the vinification of grape varieties widely produced in Brazil were investigated with a view to their exploitation as a potential source of natural antioxidants. There was a greater concentration of phenolic compounds in the seeds (2128 to 16,518 mg of catechin equivalents (CE)/100 g) than in the skins (660 to 1839 mg CE/100 g). The highest antioxidant activity values determined as DPPH radical-scavenging ability and ferric reducing-antioxidant power (FRAP) were found for the seeds of the Pinot Noir variety (16,925 mu mol Trolox equivalents (TE)/100 g and 21,492 mu mol Fe(2+)/100 g, respectively) and in the skin extracts of the Isabel variety (3640 mu mol TE/100 g and 4362 mu mol Fe(2+)/100 g, respectively). The skin of Cabernet Sauvignon and Primitivo varieties had the highest contents of anthocyanins (935 and 832 mg/100 g, respectively). The grape seed extracts were rich in oligomeric and polymeric flavanols. The data suggested that grape seed and skin extracts may be exploited as antioxidant agents. (C) 2011 Elsevier Ltd. All rights reserved.

Effect of grape seed extract on oxidative, color and sensory stability of pre-cooked, frozen, re-heated beef sausage model system

The processing of meats at the factory level can trigger the onset of lipid oxidation, which can lead to meat quality deterioration. Warmed over flavor is an off-flavor, which is associated with oxidative deterioration in meat. To avoid or delay the auto-oxidation process in meat products, synthetic and natural antioxidants have been successfully used. Grape (Vitis Vinifera) is of special interest due to its high content of phenolic compounds. Grape seed extract sold commercially as a dietary supplement, has the potential to reduce lipid oxidation and WOF in cooked ground beef when added at 1%. The objective of study 1 was to compare the antioxidant activity of natural antioxidants including grape seed extract and some herbs belonging to the Lamiaciae family: rosemary (Rosmarinus Officinalis), sage (Salvia Officinalis) and oregano (Origanum Vulgare) with commercial synthetic antioxidants like BHT, BHA, propyl gallate and ascorbic acid using the ORAC assay. All sample solutions were prepared to contain 1.8 gm sample/10 ml solvent. The highest antioxidant activity was observed for the grape seed extract sample (359.75 µM TE), while the lowest was observed for BHA, propyl gallate and rosemary also showed higher antioxidant potential with ORAC values above 300 μmol TE/g. ORAC values obtained for ascorbic acid and Sage were between 250-300μ mol TE/g while lowest values were obtained for Butylated Hydroxytoluene (28.50 µM TE). Based on the high ORAC values obtained for grape seed extract, we can conclude that byproducts of the wine/grape industry have antioxidant potential comparable to or better than those present in synthetic counterparts. The objective of study 2 was to compare three levels of grape seed extract (GSE) to commonly used antioxidants in a pre-cooked, frozen, stored beef and pork sausage model system. Antioxidants added for comparison with control included grape seed extract (100, 300, 500 ppm), ascorbic acid (AA, 100 ppm of fat) and propyl gallate (PG, 100 ppm of fat). Product was formed into rolls, frozen, sliced into patties, cooked on a flat griddle to 70C, overwrapped in PVC, and then frozen at –18C for 4 months. GSE- and PG-containing samples retained their fresh cooked beef odor and flavor longer (p<0.05) than controls during storage. Rancid odor and flavor scores of GSE-containing samples were lower (p<0.05) than those of controls after 4 months of storage. The L* value of all samples increased (p<0.05) during storage. Thiobarbituric acid reactive substances (TBARS) of the control and AA-containing samples increased (p<0.05); those of GSE-containing samples did not change significantly (p>0.05) over the storage period.

In vitro fermentation of grape seed flavan-3-ol fractions by human faecal microbiota: changes in microbial groups and phenolic metabolites

With the aim of investigating the potential of flavan-3-ols to influence the growth of intestinal bacterial groups, we have carried out the in vitro fermentation, with human faecal microbiota, of two purified fractions from grape seed extract (GSE): GSE-M (70% monomers and 28% procyanidins) and GSE-O (21% monomers and 78 % procyanidins). Samples were collected at 0, 5, 10, 24, 30 and 48 h of fermentation for bacterial enumeration by fluorescent in situ hybridization and for analysis of phenolic metabolites. Both GSE-M and GSE-O fractions promoted growth of Lactobacillus/Enterococcus and decrease in the Clostridium histolyticum group during fermentation, although the effects were only statistically significant with GSE-M for Lactobacillus/Enterococcus (at 5 and 10 h of fermentation) and GSE-O for C. histolyticum (at 10 h of fermentation). Main changes in polyphenol catabolism also occurred during the first 10 h of fermentation, however no significant correlation coefficients (P>0.05) were found between changes in microbial populations and precursor flavan-3-ols or microbial metabolites. Together these data suggest that the flavan-3-ol profile of a particular food source could affect the microbiota composition and its catabolic activity, inducing changes that could in turn affect the bioavailability and potential bioactivity of these compounds.

Gut microbial catabolism of grape seed flavan-3-ols by human faecal microbiota. Targetted analysis of precursor compounds, intermediate metabolites and end-products.

In vitro batch culture fermentations were conducted with grape seed polyphenols and human faecal microbiota, in order to monitor both changes in precursor flavan-3-ols and the formation of microbial-derived metabolites. By the application of UPLC-DAD-ESI-TQ MS, monomers, and dimeric and trimeric procyanidins were shown to be degraded during the first 10 h of fermentation, with notable inter-individual differences being observed between fermentations. This period (10 h) also coincided with the maximum formation of intermediate metabolites, such as 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone and 4-hydroxy-5-(3′,4′-dihydroxyphenyl)-valeric acid, and of several phenolic acids, including 3-(3,4-dihydroxyphenyl)-propionic acid, 3,4-dihydroxyphenylacetic acid, 4-hydroxymandelic acid, and gallic acid (5–10 h maximum formation). Later phases of the incubations (10–48 h) were characterised by the appearance of mono- and non-hydroxylated forms of previous metabolites by dehydroxylation reactions. Of particular interest was the detection of γ-valerolactone, which was seen for the first time as a metabolite from the microbial catabolism of flavan-3-ols. Changes registered during fermentation were finally summarised by a principal component analysis (PCA). Results revealed that 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone was a key metabolite in explaining inter-individual differences and delineating the rate and extent of the microbial catabolism of flavan-3-ols, which could finally affect absorption and bioactivity of these compounds.

Grape seed oil: a potential functional food?

Grape seed oil (GSO) is not often consumed in Brazil and little is known of its nutritional value. Around the world there are already studies that point to the high levels of minority bioactive compounds and their relation to health benefits. The main constituent of GSO is linoleic fatty acid, some works are controversial and there is no consensus in literature regarding their effect on the animal organism. Thus, this study aimed to present a review of GSO and show the potential health effects of its major components, not only linoleic acid, but also γ-tocotrienol and β-sitosterol, and finally, their influence on lipid-modulating, anti and pro oxidative parameters.

Mutagenicity of the Musa paradisiaca (Musaceae) fruit peel extract in mouse peripheral blood cells in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Invertase from a Candida stellata strain isolated from grape: production and physico-chemical characterization

Invertases are enzymes which hydrolyze the sucrose and are widely employed in food and pharmaceutical industries. In this work, the screening of autochthonous grape yeasts from Brazil was carried out in order to investigate their invertase production potential. Yeasts belonging to Saccharomyces, Hanseniaspora, Sporidiobolus, Issatchenkia, Candida, Cryptococcus and Pichia genera were analyzed by submerged fermentation (SbmF) using sucrose as substrate. Among them, Candida stellata strain (N5 strain) was selected as the best producer (10.6 U/ml after 48 hours of SbmF). This invertase showed optimal activity at pH 3.0 and 55°C, demonstrating appropriate characters for application in several industrial processes, which includes high temperatures and acid pHs. In addition, this invertase extract presented tolerance to low concentrations of ethanol, suggesting that it could also be suitable for application at the beginning of alcoholic fermentation. These data provide promising prospects of the use of this new invertase in food and ethanol industry.

Characterisation and oxidative stability of speciality plant seed oils

The past decade has seen an influx of speciality plant seed oils arriving into the market place. The need to characterise these oils has become an important aspect of the oil industry. The characterisation of the oils allows for the physical and chemical properties of the oil to be determined. Speciality oils were characterised based on their lipid and fatty acid profiles and categorised as monounsaturated rich (oleic acid as the major acyl components e.g. Moringa and Marula oil), linoleic acid rich (Grape seed and Evening Primrose oil) or linolenic acid rich (Flaxseed and Kiwi oil). The quality of the oils was evaluated by determining the free fatty acid content, the peroxide value (that measures initial oxidation) and p-anisidine values (that determines secondary oxidation products containing the carbonyl function). A reference database was constructed for the oils in order to compare batches of oils for their overall quality including oxidative stability. For some of the speciality oils, the stereochemistry of the triacylglycerols was determined. Calophyllum, Coffee, Poppy and Sea Buckthorn oils stereochemistry was determined. The oils were enriched with saturated and/or a monounsaturated fatty acids at position sn-1 and sn-3. The sn-2 position of the four oils was esterified with a polyunsaturated and/or a monounsaturated fatty acid indicating that they follow a typical acylation pathway and no novel acylation activity was evident from these studies (e.g enrichment of saturates at the sn-2 position). The oxidative stability of the oils was evaluated at 18oC and 60oC and the effect of adding a-tocopherol at commercially used level i.e 750ppm was assessed. The addition of 750ppm of a-tocopherol at 18oC increased the oxidative stability of Brown flax, Moringa, Wheat germ and Yangu oils. At 60oC Brown Flax, Manketti and Pomegranate oil polymerised after 48 hours. The addition of 750ppm a-tocopherol delayed the onset of polymerisation by up to 48 hours in Brown Flax seed oil. Pomegranate oil showed a high resistance to oxidation, and was blended into other speciality oils at 1%. Pomegranate oil increased the oxidative stability of Yangu oil at 18oC. The addition of Pomegranate oil to Wheat germ oil at 60oC, decreased the peroxide content by 10%. In Manketti and Brown Flaxseed oil at elevated temperatures, Pomegranate oil delayed the onset of polymerisation. Preliminary studies of Pomegranate oil blending to Moringa and Borage oil showed it to be more effective than a-tocopherol for certain oils. The antioxidant effects observed following the addition of Pomegranate oil may be due to its conjugated linolenic acid fatty acid, punicic acid.

Rheological and functional properties of flours from banana pulp and peel

Unripe banana flour can be an alternative to minimize post-harvest loss and to increase the aggregate value of banana fruit. Flour from unripe banana is rich in phytosterols and resistant starch, being proposed as health food. Flours from unripe banana peel and pulp were evaluated on their composition, phytosterols content, thermal and rheological properties, and pasting profiles. High amounts of beta-sitosterol, campesterol, and stigmasterol were found in flour from banana peel. These samples showed lower viscosity values of pasting profiles, lower energy enthalpy on gelatinization, and higher temperature of gelatinization than those ones from pulp. Anti-oxidant treatment of fruits with citric acid does not change pasting profiles of flours from pulp, but resulted in slight increase in viscosity, suggesting that structure of starch could be modified by acidification.

Use of Carnobacterium maltaromaticum cultures and hydroalcoholic extract of Lippia sidoides Cham. against Listeria monocytogenes in fish model systems

Minimally processed refrigerated ready-to-eat fishes may offer health risk of severe infection to susceptible individuals due to contamination by the psychrotolerant bacterium L monocytogenes. In this work, inhibition of L monocytogenes by a plant extract and lactic acid bacteria (IAB) was studied in model fish systems kept at 5 degrees C for 35 days. For that, fillets of tropical fish ""surubim"" (Pseudoplatystoma sp.) and hydroalcoholic extract of the plant Lippia sidoides Cham. (""alecrim pimenta"") were used. Fish peptone broth (FPB), ""surubim"" broth and ""surubim"" homogenate were inoculated with combinations of L monocytogenes and bacteriocin-producing Carnobacterium maltaromaticum (C2 and A9b(+)) and non bacteriocin-producing C. maltaromaticum (A9b(-)), in the presence or absence of extract of ""alecrim pimenta"" (EAP). In all model systems, monocultures of L monocytogenes and carnobacteria reached final populations >= 10(8) CFU/ml after 35 days, except for L monocytogenes in ""surubim"" homogenate (10(4) CFU/ml). In FPB, EAP alone and combined with cultures of LAB inhibited L monocytogenes but carnobacteria without EAP were only weakly antilisterial. In ""surubim"" broth, EAP alone did not prevent L monocytogenes growth but cultures of carnobacteria combined or not with EAP inhibited L monocytogenes, with more pronounced effect being observed for C maltaromaticum C2, which produced bacteriocin. In ""surubim"" homogenate, EAP alone and combined with cultures of C. maltaromaticum A9b(-) and A9b(+) were strongly inhibitory to L monocytogenes, while C maltaromaticum C2 with EAP caused transient inhibition of L monocytogenes. No significant inhibition of L monocytogenes was observed for carnobacteria in ""surubim"" homogenate without EAP. In conclusion, it was observed that the use of EAP and cultures of carnobacteria have potential to inhibit L monocytogenes in fish systems and the applications should be carefully studied, considering the influence of food matrix. (c) 2011 Elsevier B.V. All rights reserved.

Survival of conidia of sorghum ergot (caused by Claviceps africana) on panicles, seed and soil in Australia

Macroconidia of the sorghum ergot pathogen, Claviceps africana Frederickson, Mantle & de Milliano, survived in dried honeydew on soil for 13-14 weeks in a glasshouse at ambient temperatures, but for less than half that time on seed stored in a shadehouse over summer. Those on seeds stored at 4degreesC, however, survived for over a year (58-62 weeks). During summer, conidia on ergot-infected panicles buried in soil, or on the soil surface, survived for 7.5-12 weeks, whereas over winter the survival times were 4 weeks and 19-27 weeks, respectively. Macroconidia on infected panicles held above the soil surface survived for >38 weeks (8 calendar months) over winter, suggesting that they may play a role in the perennation of C. africana in Australia.

Taxonomic relevance of seed and seedling morphology in two Amazonian species of Entada (Leguminosae)

We carried out a comparative morphological study to evaluate the taxonomic value of seed and seedling traits of Entada polystachya and E. simplicata (Leguminosae, Mimosoideae, Mimoseae). Seeds of both species were collected from wild populations in Roraima State, Brazil. Our results show consistent quantitative and qualitative differences between these species regarding their seeds and seedlings. Testa fracture lines, funiculus impression, lens characters, radicle shape and length, and cotyledon lobes length, seedling morphology group, number of pinnae at first node, and hypocotyl length permit a straightforward distinction of E. polystachya from E. simplicata, supporting a recent treatment of the latter taxon as a distinct species, endemic to Roraima State, northern Amazonia, Brazil.