971 resultados para Food preservation technique


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A água de coco é considerada uma bebida isotônica, nutritiva e pouco calórica. A sua composição química é bastante complexa, alguns dos principais constituintes são açúcares e minerais e, em menores quantidades, Iipídeos e compostos nitrogenados. Um grande desafio é preservar a água de coco por longo período de tempo fora do fruto, mantendo as suas características físicas e organolépticas. A pasteurização é um dos processos de conservação que vem sendo utilizado com esse propósito. No entanto, pouco se sabe a respeito da influência desse processo de conservação na composição química da água de coco. Nesse sentido, a proposta desse trabalho foi investigar as espécies químicas de Cu e Zn presentes na água de coco, bem como avaliar a influência do processo de pasteurização sobre essas espécies. Para esse estudo foram feitas medidas de pH e da concentração hidrogeniônica, extração em ponto nuvem, extração por solvente, ultrafiltrações e determinação da concentração total de proteínas visando a separação com eletroforese em gel de poliacrilamida com dodecil sulfato de sódio (SOS-PAGE), e cromatografia por filtração em gel. As determinações de Cu e Zn foram feitas na água de coco total e nas frações por espectrometria de absorção atômica com atomização eletrotérmica (ETAAS). Os resultados das determinações totais de Cu e Zn, e de proteínas mostraram que a composição dessas espécies varia muito entre os diferentes frutos. A combinação dos resultados obtidos pelas diferentes técnicas indicou que o Cu está, preferencialmente, associado às moléculas de maiores pesos moleculares, enquanto que o Zn encontra-se associado a pequenas moléculas. A pasteurização não afetou o pH, a concentração total dos elementos e de proteínas. Porém, a partir dos resultados da cromatografia por filtração em gel e da determinação de Cu e Zn nas frações coletadas do eluente, foi possível observar que a pasteurização provocou alterações nos pesos moleculares das proteínas e, possivelmente nos elementos associados a elas. As mudanças observadas indicam quebra de ligações fracas, provavelmente dissulfeto, rompendo aglomerados protéicos (maior massa molecular) e aumentando a abundância de proteínas mais leves (menor massa molecular).

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In the US, one in every eight deaths is due to an obesity-related chronic health condition (ORCHC). More than half of African American women (AAW) 20 years old or older are obese or morbidly obese, as are 63% of menopausal AAW. Many have ORCHC that increase their morbidity and mortality and increase health care costs. In 2013, 42.6 percent of AAs living in South Carolina (SC) were obese. The purpose of this cross-sectional study was to identify the cognitive, behavioral, biological, and demographic factors that influence health outcomes (BMI, and ORCHC) of AAW living in rural SC. A sample of 200 AAW (50 in each of the 4 groups of rurality by menopausal status), 18-64 years, completed the: Menopausal Rating Scale (symptoms); Body Image Assessment for Obesity (self-perception of body); Mental Health Inventory; Block Food Frequency Questionnaire; Eating Behaviors and Chronic Conditions, Traditional Food Habits, and Food Preparation Technique questionnaires — and measures for Body Mass Index. Most rural, and premenopausal AAW were single and not living with a partner. Premenopausal women had significantly higher educational levels. Sixty percent of AAW had between 1 and 5 ORCHC. Most AAW used salt based seasonings, ate deep fried foods 1 to 3 times a week, and ate outside the home 1 to 3 times a month. Few AAW knew the correct daily serving for grains and dairy, and most consumed less than the recommended daily serving of fruits, vegetables and dairy. Morbidly obese AAW used more traditional food preparation techniques than obese and normal-weight AAW. Rural, and menopausal AAW had significantly higher morbid obesity levels, consumed larger portions of meats and vegetables, and reported more body image dissatisfaction than very rural AAW, and premenopausal AAW, respectively. Controlling for socioeconomic factors the relationships between perceptions of body images, psychological distress, and psychological wellbeing remained significant for numbers of ORCHC^

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In the US, one in every eight deaths is due to an obesity-related chronic health condition (ORCHC). More than half of African American women (AAW) 20 years old or older are obese or morbidly obese, as are 63% of menopausal AAW. Many have ORCHC that increase their morbidity and mortality and increase health care costs. In 2013, 42.6 percent of AAs living in South Carolina (SC) were obese. The purpose of this cross-sectional study was to identify the cognitive, behavioral, biological, and demographic factors that influence health outcomes (BMI, and ORCHC) of AAW living in rural SC. A sample of 200 AAW (50 in each of the 4 groups of rurality by menopausal status), 18-64 years, completed the: Menopausal Rating Scale (symptoms); Body Image Assessment for Obesity (self-perception of body); Mental Health Inventory; Block Food Frequency Questionnaire; Eating Behaviors and Chronic Conditions, Traditional Food Habits, and Food Preparation Technique questionnaires – and measures for Body Mass Index. Most rural, and premenopausal AAW were single and not living with a partner. Premenopausal women had significantly higher educational levels. Sixty percent of AAW had between 1 and 5 ORCHC. Most AAW used salt based seasonings, ate deep fried foods 1 to 3 times a week, and ate outside the home 1 to 3 times a month. Few AAW knew the correct daily serving for grains and dairy, and most consumed less than the recommended daily serving of fruits, vegetables and dairy. Morbidly obese AAW used more traditional food preparation techniques than obese and normal-weight AAW. Rural, and menopausal AAW had significantly higher morbid obesity levels, consumed larger portions of meats and vegetables, and reported more body image dissatisfaction than very rural AAW, and premenopausal AAW, respectively. Controlling for socioeconomic factors the relationships between perceptions of body images, psychological distress, and psychological wellbeing remained significant for numbers of ORCHC

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Syzygium anisatum (formerly Backhousia anisata and Anetholea anisata) is an Australian rainforest tree with leaves that produce an essential oil (EO) that has the characteristic aroma of aniseed. It is referred to as aniseed myrtle or anise myrtle in the trade and the fresh and dried leaves of this plant are used as a herb in culinary applications. The EO is extracted by steam distillation of the leaves and the major aromatic volatile compound is anethole. The EO has broad spectrum antimicrobial activity but is more effective against bacteria than fungi. Indigenous Australians have used anise myrtle for its medicinal values and in recent times it has been used as a flavoring agent by the food and beverage industry. This chapter covers the use of anise myrtle EO in food and agricultural applications, botanical aspects, and chemical composition.

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Lemon myrtle has been traditionally used by indigenous Australians for cooking and healing. More recently, lemon myrtle leaves are used as a dry or fresh herb in food applications and the essential oil (EO) used as a flavoring agent in food and beverages. The leaf of the lemon myrtle (Backhousia citriodora) is steam distilled to produce the EO. Lemon myrtle EO is known for its characteristic lemon flavor and the major chemical component contributing to the aroma is citral. The EO has broad spectrum antimicrobial activity and is very effective against fungi and has increased the potential of using the EO in food preservation and treatment of postharvest diseases in fruits. This chapter covers the use of lemon myrtle EO in food and agriculture applications, general usage, botanical aspects, and chemical composition.

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Tasmannia lanceolata, commonly known as Tasmanian pepper leaf or mountain pepper, is an Australian native plant that produces an essential oil with a characteristic pungent flavor attributed to the sesquiterpene polygodial. The dried and fresh leaves are used in culinary applications. The essential oil is produced by a solvent extraction process, and the resultant concrete is a rich source of the principal pungent molecule polygodial and other volatiles. The Tasmanian pepper leaf extract has broad-spectrum antimicrobial activity and is very effective against fungi, especially yeasts. This demonstrates its potential to be used in the food industry as a natural preservative. Indigenous Australians have used Tasmanian pepper leaves for therapeutic purposes; in recent times, it is been used as a flavoring agent and enhancer of pungency in food products. This chapter covers the use of Tasmanian pepper leaf essential oil in food applications, its botanical aspects, and its chemical composition.

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Boletus edulis Bull: Fr. is an edible mushroom quite appreciated for its organoleptic and nutritional properties. However, the seasonality and perishability cause some difficulties in its distribution and marketing in fresh form; losses associated with this type of food during marketing can reach 40% [1]. Irradiation is recognized as a safe and effective method for food preservation, being used worldwide to increase shelf life of fresh and dehydrated products (e.g. fruits, vegetables and spices) [2]. In particular, gamma irradiation has already been applied to cultivated mushrooms (especially Agaricus, Lentinula and Pleurotus Genus) and proved to be an interesting conservation technology [3]. However, the studies with added-value wild species are scarce. In this work, the effects of gamma irradiation on chemical and antioxidant properties of wild B. edulis, were evaluated. Fruiting bodies were obtained in Trás-os-Montes, in the Northeast of Portugal, in November 2012. The irradiation was performed in experimental equipment with 60Co sources at 1 and 2 kGy. All the results were compared with nonirradiated samples (control). Macronutrients and energy value were determined following official procedures of food analysis; fatty acids were analyzed by gas-chromatography coupled to flame ionization detection (GC-FID), while sugars and tocopherols were determined by high performance liquid chromatography (HPLC) coupled to refraction index (RI) and fluorescence detectors, respectively. Antioxidant activity was evaluated in the methanolic extracts by in vitro assays measuring DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of β- carotene bleaching and inhibition of lipid peroxidation using thiobarbituric acid reactive substances (TBARS) assay. Total phenolics were also determined by the Folin-Ciocalteu assay. The nutritional profiles were not affected in high extension. Fatty acids and sugars were slightly affected, decreasing with the increasing doses. The performed assays for antioxidant activity, indicate that irradiated samples tended to have lower scavenging activity and reducing power, but higher lipid peroxidation inhibition. Despite the detected differences in individual compounds, the results of nutritional parameters, the most relevant in terms of mushroom acceptability by consumers, were less affected, indicating an interesting potential of gamma-irradiation to be used as an effective conservation technology for the studied mushrooms.

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Jellyfish are increasingly topical within studies of marine food webs. Stable isotope analysis represents a valuable technique to unravel the complex trophic role of these long-overlooked species. In other taxa, sample preservation has been shown to alter the isotopic values of species under consideration, potentially leading to misinterpretation of trophic ecology. To identify potential preservation effects in jellyfish, we collected Aurelia aurita from Strangford Lough (54(o)22'44.73aEuro(3)N, 5(o)32'53.44aEuro(3)W) during May 2009 and processed them using three different methods prior to isotopic analysis (unpreserved, frozen and preserved in ethanol). A distinct preservation effect was found on delta N-15 values: furthermore, preservation also influenced the positive allometric relationship between individual size and delta N-15 values. Conversely, delta C-13 values remained consistent between the three preservation methods, conflicting with previous findings for other invertebrate, fish and mammalian species. These findings have implications for incorporation of jellyfish into marine food webs and remote sampling regimes where preservation of samples is unavoidable.

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Increasing survival rates in young cancer patients, new reproductive techniques and the growing interest in quality of life after gonadotoxic cancer therapies have placed fertility preservation as an important issue to oncologists, fertility specialists and patients. Several techniques are now available for fertility preservation in these patients. A new promising method is cryopreservation and transplantation of ovarian cortex. Ovarian tissue can be extracted by laparoscopy without any significant delay of gonadotoxic therapy. The tissue can be cryopreserved by specialised centres of reproductive medicine and transplanted in case the women experience premature ovarian failure (POF). This review summarises the European expertise on cryopreservation and transplantation of ovarian tissue, following around 30 reported transplantations globally, resulting in six live births and several ongoing pregnancies. It emphasises that fertility preservation by the cryopreservation of ovarian tissue is a new but already a successful clinical option, which can be considered for selected cancer patients.

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L’abeille domestique (Apis mellifera Linnaeus) joue un rôle crucial comme pollinisateur dans l’industrie de l’agriculture. Cependant, durant les dernières décennies, une mortalité des colonies d’abeilles a été observée partout à travers le monde. La conservation du sperme d’abeille est un outil efficace pour sauvegarder la diversité génétique. Sa conservation est possible à température pièce, mais la cryoconservation serait une meilleure méthode pour la conservation à long terme. Notre objectif général est de développer une méthode de cryoconservation de la semence d’abeille. L’hypothèse no.1 était que la cryoconservation de la semence d’abeille est plus efficace à long terme que les températures au-dessus de 0 °C. Nous avons évalué l’efficacité, basé sur la viabilité des spermatozoïdes, de deux températures de conservation: -196 °C et 16 °C. Après un an de conservation, la semence congelée avait une meilleure viabilité comparée à 16°C (76% ± 5% vs 0%; p < 0,05). Par la suite, la spermathèque des reines inséminées avec la semence cryoconservée a été évaluée par la migration des spermatozoïdes ainsi que la viabilité des spermatozoïdes. Il y avait beaucoup de variabilités dans nos résultats. Nous n’avons pas été en mesure de vérifier si l’ajout de la centrifugation après la conservation améliore la fertilité des reines après insémination. Toutefois, nos résultats confirment que la cryoconservation est une technique efficace pour conserver la semence d’abeille à long terme.

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Background Malnutrition is common among dialysis patients and is associated with an adverse outcome. One cause of this is a persistent reduction in nutrient intake, suggesting an abnormality of appetite regulation. Methods We used a novel technique to describe the appetite profile in 46 haemodialysis (HD) patients and 40 healthy controls. The Electronic Appetite Rating System (EARS) employs a palmtop computer to collect hourly ratings of motivation to eat and mood. We collected data on hunger, desire to eat, fullness, and tiredness. HD subjects were monitored on the dialysis day and the interdialytic day. Controls were monitored for 1 or 2 days. Results Temporal profiles of motivation to eat for the controls were similar on both days. Temporal profiles of motivation to eat for the HD group were lower on the dialysis day. Mean HD scores were not significantly different from controls. Dietary records indicated that dialysis patients consumed less food than controls. Conclusions Our data indicate that the EARS can be used to monitor subjective appetite states continuously in a group of HD patients. A HD session reduces hunger and desire to eat. Patients feel more tired after dialysis. This does not correlate with their hunger score, but does correlate with their fullness rating. Nutrient intake is reduced, suggesting a resetting of appetite control for the HD group. The EARS may be useful for intervention studies.

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In humans the presence of negative affect is thought to promote food intake, but there is widespread variability. Susceptibility to negative affect-induced eating may depend on trait eating behaviours, notably ‘emotional eating’, ‘restrained eating’ and ‘disinhibited eating’, but the evidence is not consistent. In the present study, 30 non-obese, non-dieting women were given access to palatable food whilst in a state of negative or neutral affect, induced by a validated autobiographical recall technique. As predicted, food intake was higher in the presence of negative affect; however, this effect was moderated by the pattern of eating behaviour traits and enhanced wanting for the test food. Specifically, the High Restraint-High Disinhibition subtype in combination with higher scores on emotional eating and food wanting was able to predict negative-affect intake (adjusted R2 = .61). In the absence of stress, individuals who are both restrained and vulnerable to disinhibited eating are particularly susceptible to negative affect food intake via stimulation of food wanting. Identification of traits that predispose individuals to overconsume and a more detailed understanding of the specific behaviours driving such overconsumption may help to optimise strategies to prevent weight gain.