952 resultados para Semiarid. Cactaceae. Algaroba. Bioactive compounds. Food functionality. Sensory evaluation


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Recent surveys have identified anthelmintic effects from many bioactive substances particularly from condensed tannin (CT) sources. The aims of the present study were to investigate the potential anthelmintic effects of condensed tannins (CT) on Trichostrongylus colubriformis in experimentally infected sheep and the nutritional consequences on animals. Twenty helminth-free lambs were divided into five groups of four animals. Groups I to IV were artificially infected with 6,000 third stage larvae (L3) of T. colubriformis. Group I was the infected control and group V was the uninfected control. Twenty-eight days post-infection (p.i.) lambs from GII were supplemented with tanniniferous sorghum (350 g/animal/day, during seven days); GIII were drenched with Acacia mearnsii extract (15% CT) for just one day and GIV during two days (1.6 g extract/kg BW). At day 36 p.i., animals from infected group (GI to GIV) were slaughtered. Faecal egg counts (FEC) values present a reduction on GII when compared with GI at day 29 p.i. (P < 0.05) and between GIII and GI at day 35 and 36 p.i. (P < 0.05). The values of egg hatchability and number of L3 recovered from the faeces were not statistical analyzed (there was no duplicate data), however there was a considerable reduction between the values from treated and control group. The use of CT on diet did not cause significant difference on blood parameters, body-weight and carcass-weight (P > 0.05). No difference was related on total worm burden between treatments; however, GIV presented lower number of females than GI (P < 0.05). The use of CT could be a promising alternative source to reduce the pasture contamination and to control T. colubriformis infection in sheep.

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P>The aim of the present work was to evaluate the use of the kefir grains as a starter culture for tradicional milk kefir beverage and for cheese whey-based beverages production. Fermentation was performed by inoculating kefir grains in milk (ML), cheese whey (CW) and deproteinised cheese whey (DCW). Erlenmeyers containing kefir grains and different substrates were statically incubated for 72 h at 25 degrees C. Lactose, ethanol, lactic acid, acetic acid, acetaldehyde, ethyl acetate, isoamyl alcohol, isobutanol, 1-propanol, isopentyl alcohol and 1-hexanol were identified and quantified by high-performance liquid chromatography and GC-FID. The results showed that kefir grains were able to utilise lactose in 60 h from ML and 72 h from CW and DCW and produce similar amounts of ethanol (similar to 12 g L-1), lactic acid (similar to 6 g L-1) and acetic acid (similar to 1.5 g L-1) to those obtained during milk fermentation. Based on the chemical characteristics and acceptance in the sensory analysis, the kefir grains showed potential to be used for developing cheese whey-based beverages.

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The objective of this study was to evaluate the sensory stability of ultra-high temperature (UHT) milk subjected to different heat treatments and stored at room temperature in white high density polyethylene bottles (HDPE) pigmented with titanium dioxide. Two lots of 300 units each were processed, respectively, at 135 and 141 degrees C/10 s using indirect heating and subsequently aseptically filled in an ISO class 7 clean room. These experimental lots were evaluated for appearance, aroma, flavor, and overall appreciation and compared to samples of commercial UHT milk purchased from local commercial stores. The time-temperature combinations investigated did not affect either the acceptability or the shelf life of the milk. Despite the limited light barrier properties of HDPE bottles, the product contained in the package tested exhibited good stability, with a shelf life ranging from 4 to 11 wk. Within this time period, the acceptability of the experimental lots was similar to that of the commercial products. The results achieved in this study contribute to turn the low-cost UHT system investigated into a technically viable option for small-size dairy processing plants.

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Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 +/- 1 degrees C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P < 0.05) in the psychrotrophic bacterial count as from the 7th day of refrigerated storage, for the MDCM samples irradiated at the dose rate of 4.04 kGy/h. With respect to the attribute of oxidized odor, the samples irradiated with a dose rate of 0.32 kGy/h showed a stronger intensity and were significantly different (P < 0.05) from the sample irradiated with a dose rate of 4.04 kGy/h on days 0 and 2 of refrigerated storage. Irradiation with a dose rate of 4.04 kGy/h (3 kGy) was shown to be the best condition for the processing of MDCM according to the evaluation of all the variables, under the conditions of this study. Practical Application The results obtained for the application of different dose rates of ionizing radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

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BACKGROUND: This study reported the effects of the daily intake of anthocyanins and ellagitannins (ET) extracted from blackberries on the markers for oxidative status in healthy rats. RESULTS: The phenolic compounds were administered from three different extracts: an aqueous extract of blackberry (BJ) and its two derived fractions: anthocyanin-enriched (AF) and ET-enriched (EF) fractions. After 35 days` administration, the AF and EF extracts significantly reduced thiobarbituric acid reactive substance levels and increased glutathione levels in the liver, kidney and brain. Plasma antioxidant capacity increased only in the group that received AF. Antioxidant enzyme activity and expression did not follow a pattern of response varying according to the tissues and extracts. A significant increase in the catalase activity was observed only in the plasma of the groups administered anthocyanin-containing extracts, which were the BJ and AF groups. Glutathione peroxidase activity was significantly increased in the liver and brain after EF treatment, and the highest increase in its expression was observed in the livers and brains of rats that received AF and EF, respectively. CONCLUSION: The results demonstrate that long-term intake of anthocyanin and ET through diet affects antioxidant enzyme activity and expression, and enhances oxidative markers in healthy rats. (C) 2010 Society of Chemical Industry

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The effects of refrigeration, freezing and substitution of milk fat by inulin and whey protein concentrate (WPC) on the texture and sensory features of synbiotic guava mousses supplemented with the probiotic, Lactobacillus acidophilus La-5, and the prebiotic fibre oligofructose, were studied. The frozen storage (-18 +/- 1 degrees C), followed by thawing at 4 degrees C before the analyses, and the complete replacement of the milk fat by inulin plus WPC, led to significant differences in the instrumental texture parameters of mousses (P < 0.05). Nonetheless, these changes did not affect the sensory acceptability of the products studied. The frozen storage may be employed to extend the shelf-life of synbiotic guava mousses. Additionally, to obtain a texture profile similar to the traditional product, the simultaneous addition of inulin and WPC is recommended only for the partial replacement of milk fat in refrigerated and frozen mousses, and the total proportion of both ingredients together should not exceed 2.6%. (C) 2010 Elsevier Ltd. All rights reserved.

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Red currants (Ribes rubrum L.), black currants (Ribes nigrum L.), red and green gooseberries (Ribes uva-crispa) were evaluated for the total phenolics, antioxidant capacity based on 2, 2-diphenyl-1-picrylhydrazyl radical scavenging assay and functionality such as in vitro inhibition of alpha-amylase, alpha-glucosidase and angiotensin I-converting enzyme (ACE) relevant for potential management of hyperglycemia and hypertension. The total phenolics content ranged from 3.2 (green gooseberries) to 13.5 (black currants) mg/g fruit fresh weight. No correlation was found between total phenolics and antioxidant activity. The major phenolic compounds were quercetin derivatives (black currants and green gooseberries) and chlorogenic acid (red currants and red gooseberries). Red currants had the highest alpha-glucosidase, alpha-amylase and ACE inhibitory activities. Therefore red currants could be good dietary sources with potential antidiabetes and antihypertension functionality to compliment overall dietary management of early stages of type 2 diabetes.

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Foods provide essential and bioactive compounds with health-promoting properties such as antioxidant, anti-inflammatory, and hypocholesterolemic activities, which have been related to vitamins A, C, and E and phenolic compounds such as flavonoids. Therefore, the aim of this work was to identify potential sources of bioactive compounds through the determination of flavonoids and ellagic acid contents and the in vitro antioxidant capacity and alpha-glucosidase and alpha-amylase inhibitory activities of Brazilian native fruits and commercial frozen pulps. Camu-camu, cambuci, uxi, and tucuma and commercial frozen pulps of cambuci, cagaita, coquinho azedo, and araca presented the highest antioxidant capacities. Cambuci and cagaita exhibited the highest alpha-glucosidase and alpha-amylase inhibitory activities. Quercetin and kaempferol derivatives were the main flavonoids present in most of the samples. Ellagic acid was detected only in umbu, camu-camu, cagaita, araca, and cambuci. According to the results, native Brazilian fruits can be considered as excellent sources of bioactive compounds.

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Several epidemiological and research studies suggest that a high intake of foods rich in natural antioxidants increases the antioxidant capacity of the plasma and reduces the risk of some kinds of cancers, heart diseases, and stroke. These health benefits are attributed to a variety of constituents, including vitamins, minerals, fiber, and numerous phytochemicals, such as flavonoids. Thus, in addition to measuring the composition of the usual macronutrients and micronutrients, it seems important to also measure the antioxidant capacity of foods. For this purpose, 28 foods including fruits, vegetables and commercially-frozen fruit pulps were analyzed for antioxidant capacity. The antioxidant capacity of the foods varied from 0.73 to 19.8 mu mol BHT equiv/g. The highest values were observed for wild mulberries (19.8 mu mol BHT equiv/g), acai fruit pulp (18.2 mu mol BHT equiv/g) and watercress (9.6 mu mol BHT equiv/g). The antioxidant capacities are only indicative of the potential of the bioactive compounds; however, these data are important to explore and understand the role of fruit, vegetables and other foods in health promotion. (C) 2009 Elsevier Inc. All rights reserved.

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Sensory analysis is a precise and descriptive measuring technique to quantify human responses to stimuli. Odor, one of these stimuli, is basically the result of the interaction between a chemical stimulus and the olfactory receptor system, which can be described using a number of different dimensions and measures through different sensory tests: threshold, intensity and quality. To measure fragrance performance on the skin, these parameters are very important, but the main attribute to be evaluated is substantivity, thus the importance of the sensory scale chosen to measure perception, discriminate different intensities and determine the substantivity of the fragrance. Some studies comparing the labeled magnitude scale (LMS) with other magnitude scales and their derivations showed that the use of the LMS scale to measure fragrance intensity could semantically understand the intensity of the stimulus. Tests using this scale confirmed the applicability and efficiency of the LMS. PRACTICAL APPLICATIONS The objective of this article is to review the techniques used to measure odor and fragrance intensities applied on the skin. The review shows general sensory techniques and their goals, the newest olfactory mechanism and its contribution to sensory evaluation and which attributes should be considered to measure odor. Substantivity/retentivity or longevity can be regarded as the most important attributes if you want to measure fragrance performance on the skin. Past studies showed different scales tested to measure odor, and some of them demonstrated that the labeled magnitude scale is very suitable to measure fragrance on the skin.

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The development of sunscreens containing reduced concentration of chemical UV filters, even though, possessing broad spectrum effectiveness with the use of natural raw materials that improve and infer UV absorption is of great interest. Due to the structural similarities between polyphenolic compounds and organic UV filters, they might exert photoprotection activity. The objective of the present research work was to develop bioactive sunscreen delivery systems containing rutin, Passiflora incarnata L. and Plantago lanceolata extracts associated or not with organic and inorganic UV filters. UV transmission of the sunscreen delivery system films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection efficacy was evaluated according to the following parameters: estimated sun protection factor (SPF); Boot`s Star Rating category; UVA/UVB ratio; and critical wavelength (lambda(c)). Sunscreen delivery systems obtained SPF values ranging from 0.972 +/- 0.004 to 28.064 +/- 2.429 and bioactive compounds interacted with the UV filters positive and negatively. This behavior may be attributed to: the composition of the delivery system: the presence of inorganic UV filter and quantitative composition of the organic UV filters; and the phytochemical composition of the P. incarnate L and P. lanceolato extracts. Among all associations of bioactive compounds and UV filters, we found that the broad spectrum sunscreen was accomplished when 1.68% (w/w) P incarnata L. dry extract was in the presence of 7.0% (w/w) ethylhexyl methoxycinnamate, 2.0% (w/w) benzophenone-3 and 2.0% (w/w) TiO(2). It was demonstrated that this association generated estimated SPF of 20.072 +/- 0.906 and it has improved the protective defense against UVA radiation accompanying augmentation of the UVA/UVB ratio from 0.49 to 0.52 and lambda(c) from 364 to 368.6 nm. (c) 2008 Elsevier B.V. All rights reserved.

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Sensory acceptance of four trials of probiotic petit-suisse cheese was investigated. Cheeses were prepared using Streptococcus thermophilus TA 040 as starter not supplemented with any probiotic culture (T1-control), Lactobacillus acidophilus La-5 (T2), Bifidobacterium animalis subsp. lactis BL04 (T3) and L. acidophilus + B. animalis subsp. lactis (T4). Sensory acceptance tests were performed after 7 and 14 days of storage at 4 +/- 1 degrees C, using a 9-point hedonic scale to evaluate flavour, texture and overall acceptability. The population of La-5 and BL04 remained at 7.0 log CFU g(-1) and at 8.0 log CFU g(-1), respectively, during storage for up to 28 days. After 7 and 14 days of storage, cheese T4 presented the highest sensory acceptance for all attributes evaluated and differed significantly from the other cheeses (P<0.05). After 14 days of storage, cheese T3 presented the lowest acceptance and differed significantly from the other cheeses (P<0.05). The supplementation of petit-suisse cheese T4 with both La-5 and BL04 in co-culture with a starter culture resulted in a product with high probiotic populations during storage and excellent sensory acceptance. The results also showed that, when added separately, La-5 and BL04 did not affect the sensory acceptability of petit-suisse cheese.

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Much information on flavonoid content of Brazilian foods has already been obtained; however, this information is spread in scientific publications and non-published data. The objectives of this work were to compile and evaluate the quality of national flavonoid data according to the United States Department of Agriculture`s Data Quality Evaluation System (USDA-DQES) with few modifications, for future dissemination in the TBCA-USP (Brazilian Food Composition Database). For the compilation, the most abundant compounds in the flavonoid subclasses were considered (flavonols, flavones, isoflavones, flavanones, flavan-3-ols, and anthocyanidins) and the analysis of the compounds by HPLC was adopted as criteria for data inclusion. The evaluation system considers five categories, and the maximum score assigned to each category is 20. For each data, a confidence code (CC) was attributed (A, B, C and D), indicating the quality and reliability of the information. Flavonoid data (773) present in 197 Brazilian foods were evaluated. The CC ""C"" (as average) was attributed to 99% of the data and ""B"" (above average) to 1%. The main categories assigned low average scores were: number of samples; sampling plan and analytical quality control (average scores 2, 5 and 4, respectively). The analytical method category received an average score of 9. The category assigned the highest score was the sample handling (20 average). These results show that researchers need to be conscious about the importance of the number and plan of evaluated samples and the complete description and documentation of all the processes of methodology execution and analytical quality control. (C) 2010 Elsevier Inc. All rights reserved.

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BACKGROUND: This study evaluated the effect of a potentially probiotic bacteria (Lactobacillus paracasei subsp. paracasei LBC 82), added solely or together with the prebiotic ingredient inulin on instrumental texture attributes and sensory properties of a functional chocolate mousse during storage at 4 +/- 1 degrees C for up to 28 days. RESULTS: The addition of Lactobacillus paracasei resulted in a firmer and more adhesive chocolate mousse. This effect was intensified with the presence of inulin in the synbiotic formulation (5.24 N and -0.956 N, respectively, for firmness and adhesiveness after 28 days of storage) (P < 0.05). L. paracasei population did not vary (P > 0.05) during storage (always between 7.27 and 7.35 log cfu g(-1)), both for the probiotic and the synbiotic mousses. Synbiotic mousse differed from control and probiotic mousses during storage with respect to the color attribute. Moreover, both probiotic and synbiotic mousses presented taste, aroma and texture perceptions which were different from one another and from the control mousse after 14 and 21 days of storage. CONCLUSION: The use of inulin, together with the potentially probiotic strain of Lactobacillus paracasei subsp. paracasei, is advantageous, conferring potentially symbiotic potential to the chocolate mousse, as well as favorable texture and sensory properties. (c) 2008 Society of Chemical Industry.

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The influence of inulin, oligofructose and oligosaccharides from honey, combined in different proportions, on the consumers` sensory acceptance, probiotic viable count and fructan content of novel potentially synbiotic petit-suisse cheeses was investigated. Probiotic populations varied from 7.20 up to 7.69 log cfu g(-1) (Bifidobacterium animalis subsp. lactis) and from 6.08 up to 6.99 log cfu g(-1) (Lactobacillus acidophilus). The highest fructan contents were achieved by the cheese trials containing oligofructose and/or inulin (above 8.90 g 100 g(-1)). The control trial showed the lowest mean acceptance (6.63) after 28 days of refrigerated storage, whereas the highest acceptance (7.43) was observed for the trial containing 10 g 100 g(-1) oligofructose. Acceptance increased significantly during storage (P < 0.05) only for cheeses supplemented with oligoftuctose and/or inulin. Cheeses containing honey did not perform well enough compared to the cheeses with addition of inulin and/or oligofructose, and the best synbiotic petit-suisse cheese considering sensory and technological functional features was that containing oligofructose and inulin combined, therefore encouraging the commercial product use. (c) 2007 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.