Maria de Fátima Píccolo Barcelos

Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours

Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% and 10.86%, respectively. The in natura pulp presented a higher moisture and carboydrate content and lower lipid, protein, total dietary fiber, and ash than those of the peel flour. The same pattern was observed for pulp flour when compared to peel flour. The highest tannin, nitrate, and oxalic acid levels were found in the peel flour, 15,304.5 mg.kg-1, 1,578.3 mg.kg-1, and 7,925.0 mg.kg-1 (wet weight), respectively. The polyphenoloxidase and peroxidase enzymes presented higher enzymatic activity in the yacon peel. Based on the results obtained, it can be said that the yacon and its derivatives are important dietary carbohydrate and mineral sources and contain antinutritional substance contents lower than those harmful to health.

Characterization of food bars manufactured with agroindustrial by-products and waste

Food bars are products obtained from the union of a number of components, standing out in the snack category due to their portability attribute with a focus on convenience and health. Utilization of by-products and agroindustrial food waste as ingredients in the making of food bars is highly important due to the utilization of leftovers of marked nutritional and functional value and decrease of the production cost. This work intended to evaluate the chemical and physicochemical aspects of food bars made with the by-products broken rice (BR) and pequi nut (PN), soybean extract residue (SER), and pineapple waste (PW). Distinct proportions of BR: SER respectively were used, amounting to five treatments: 1:0 (A); 3:1 (B); 1:1 (C); 1:3 (D) and 0:1(E) and fixed amounts of the other components. For the statistical analysis, variance analysis and the Tukey test were performed to 5% significance. The moisture, protein, lipid, ash, mineral, and dietary fiber contents were directly increased as the SER was increased and the amount of BR was decreased. However, the opposite was found with both carbohydrates and calories. The soluble solids, pH and water activity values presented increases with the increased soybean extract residue. All the treatments presented slightly acidic pH and water activity bellow 0.6, favoring microbiological safety. In the chemical score, treatment A presented lysine as the limiting aminoacid in relation to the Food and Agriculture Organization - FAO/WHO reference (1990). The food bars can be considered rich in dietary fiber and with considerable nutritional support. Treatments D and E proved better in the set of the variables studied for human consumption.

Efeito de diferentes tipos de fibras sobre frações lipídicas do sangue e fígado de ratos wistar

Conduziu-se o presente estudo, com o objetivo de avaliar o efeito de diferentes tipos de fibras sobre as fracoes lipidicas do sangue e figado de ratos. Para determinar o efeito da pectina citrica, goma guar e celulose sobre o perfil lipidico dos ratos utilizaramse 36 ratos machos da linhagem wistar. Os ratos foram distribuidos aleatoreamente em seis grupos. Cada gruopo foi submetido a uma dieta por 58 dias. As dietas utilizadas foram: A- 10% de pectina, B - 15% de pectina, C - 10% de goma guar, D- 15% de goma guar, E - 5% de Celulose sem colesterol e F - 5% celulose com 1% de colesterol. A pectina e a goma guar evitaram o aumento do colesterol total e LDL-c serico observado na dieta F (p<0,05). Nao houve diferenca significativa entre os tipos de fibras e a quantidades utilizadas. Os niveis sericos HDL-c, VLDL-c e TAG permaneceram inalterados em todos os tratamentos. Os resultados mostram o potencial efeito benefico da ingestao das fibras soluveis pectina e goma guar no controle da colesterolemia.

Efeito das fibras dos farelos de trigo e aveia sobre o perfil lipídico no sangue de ratos (Rattus norvegicus) wistar

Com o objetivo de determinar os efeitos das fontes de fibras de farelo de aveia e trigo sobre o perfil lipidico no sangue de ratos (Rattus norvegicus) wistar, conduziu-se este ensaio utilizando-se 48 animais, os quais foram distribuidos em um delineamento ao acaso e divididos em oito grupos. Durante um periodo de seis dias, os animais receberam dietas padrao para se adaptarem ao experimento. Apos esse periodo, os animais receberam dietas distintas por 63 dias, sendo elas compostas com 5, 10 e 15% de farelo de aveia e 1% de colesterol e outras tres compostas por 5,10 e 15% de farelo de trigo como fonte de fibra e 1% de colesterol. Havia dois grupos-controle, sendo o primeiro isento de colesterol e com 5% de celulose como fonte de fibra e o segundo com 1% de colesterol. Apos os 63 dias recebendo as dietas experimentais, os animais se submeteram as mesmas analises de colesterol, HDL, LDL, VLDL e triacilglicerol no sangue. Os ratos alimentados com farelo de aveia 5, 10 e 15% tiveram reducao significativa do colesterol serico em relacao ao grupo controle contendo 1% de colesterol e aos alimentados com 1% de colesterol. Os niveis de HDL foram maiores nos grupos alimentados com 10 e 15% do farelo de aveia do que nos grupos alimentados com 5% de farelo de aveia e com farelo de trigo a 5,10 e 15%. Nao houve diferenca estatistica em relacao ao grupo controle e os alimentados com farelo de aveia 10 e 15%. A concentracao de LDL apresentou-se menor no tratamento com 15% em relacao ao controle contendo colesterol e aos tratamentos com farelo de trigo. Ja o os niveis de triacilglicerol e VLDL foram significativamente menores nos animais alimentados com 15% dos farelos de aveia e trigo em relacao a todos os outros tratamentos. Conclui-se, neste experimento, que o perfil lipidico pode ser melhorado com a adicao do farelo de aveia a dieta e que o farelo de trigo exerce pouca influencia apenas nos niveis de triacilglicerol sericos.

Avaliação da alimentação escolar oferecida aos alunos do ensino fundamental das escolas municipais de Lavras, MG

Objetivou-se no presente estudo avaliar a alimentacao escolar (AE) oferecida aos alunos do ensino fundamental (EF) nas unidades escolares municipais (UEM), urbanas (EU) e rurais (ER), de Lavras, MG, de forma gratuita, em funcao do repasse financeiro do Programa Nacional de Alimentacao Escolar (PNAE), quanto a composicao quimica e atendimento da meta de fornecer 15% das necessidades nutricionais dos alunos. A coleta de amostras para a analise da composicao quimica foi realizada aleatoriamente, em todas as UEM durante o ano de 2004. A analise da AE apresentou valores diarios medios de 189kcal, 7,5g de proteina, 72,9mg de Ca, 16,7mg de Mg, 2,2mg de Fe e 1,4mg de Zn. Para o atendimento da meta de fornecer 15% das necessidades nutricionais, do total de dezesseis escolas estudadas, o teor de energia e calcio encontrava-se abaixo do recomendado em quinze escolas, sendo que apenas uma do meio urbano atendeu a proporcao de energia e uma do meio rural atendeu quanto ao teor de calcio; para o magnesio so tres escolas, duas urbanas e uma rural, atingiram a meta; o oferecimento de proteina e ferro foi atingido por todas as escolas estudadas. Conclui-se que a meta de fornecer 15% das NN na alimentacao escolar nao foi totalmente atingida, pois a maioria das adequacoes ficou fora da faixa recomendada pelo PNAE.

Effects of the kefir and banana pulp and skin flours on hypercholesterolemic rats.

PURPOSE To investigate the effect of kefir and banana pulp and skin flours on the serum levels of total cholesterol, HDL-c, LDL-c and triacylglycerols in rats fed cholesterol-rich diet. METHODS Thirty Male Wistar rats were used. In the first 21 days, the animals were fed purified hypercholesterolemic diets, except the standard group. In the next 21 days, the animals were given modified diets: Group GC: standard diet AIN-93G; Group HIP: hypercholesterolemic diet; Group F: hypercholesterolemic diet added of 1% of banana skin flour and 7% of banana pulp flour; Group Q: hypercholesterolemic diet plus kefir suspension by oral infusion (1.5 ml/animal); Group FQ: hypercholesterolemic diet added of 1% banana skin flour and 7% of banana pulp flour plus kefir suspension (1.5 ml/animal). RESULTS In spite of the high fiber content, the addition of banana pulp (7%) and skin (1%) flour did not alter the plasma levels of total cholesterol, HDL-c and LDL-c. However, they reduced the TG levels in 22%. Already fermented kefir reduced significantly the levels of VLDL, LDL-c and triacylglycerols, in addition to having increased HDL-c. However, it was not possible to verify the symbiotic effect between both. CONCLUSION The results reinforce the beneficial effects of kefir in reducing the risks of cardiovascular diseases.

Características sensoriais e físicas de extratos e tofus de soja comum processada termicamente e livre de lipoxigenase

The overall objective of this study was to select a process for producing soybean milk and curd (tofu) that results in a pleasant-tasting product. The specific objective was to ascertain how bleaching and nonbleaching of conventional soybeans, prior to soaking, affects the physical and sensorial characteristics of the soymilk and tofu, and to compare the color, taste, appearance and texture of soymilk and tofu obtained from unbleached soybeans (BRS 133 cultivar), from bleached soybeans (BRS 133 cultivar), and from lipoxygenase-free soybeans (BRS 213 cultivar). The bleaching process was found to be indispensable to enhance the flavor of soybean milk. Bleaching did not affect the appearance or color of soybean milk in comparison with lipoxygenase-free soybean milk, but the used of bleached soybeans negatively affected the flavor, texture and appearance of tofu, although its color was not affected.

Total antioxidant activity of dried tomatoes marketed in Brazil

The main antioxidant compounds (lycopene, β-carotene, total phenolic, and vitamin C) and total antioxidant activity in eight dried tomatoes marketed in Brazil were determined. The total antioxidant activity was determined by the DPPH radical scavenging method and the β-carotene/linoleic acid system in both hydrophilic and hydrophobic extracts. The contents of the antioxidant compounds varied significantly among the products analyzed. The hydrophobic extracts showed higher antioxidant activity with the β-carotene/linoleic acid system while the hydrophilic extracts showed higher antioxidant activity with the DPPH method. Despite differences found, the dried tomatoes can be considered products with high contents of antioxidant compounds with high antioxidant activity.

Composição química e conteúdo de ferro solúvel em soja [Glycine max (L.) Merrill]

A soja e um grao que possui um dos maiores teores de proteina e ferro entre os alimentos de origem vegetal e teve a sua utilizacao muito aumentada nos ultimos anos, principalmente por lactentes que tem problemas de intolerância ao leite de vaca em todo mundo. Em razao da sua grande quantidade de ferro, a soja tem sido investigada quanto a sua capacidade de recuperacao de individuos anemicos. No passado, a investigacao baseou-se somente na sua quantidade de ferro total, nao considerando as fracoes soluveis (mais biodisponiveis) das insoluveis (que sao mais dificilmente absorvidas). Objetivou-se com este trabalho realizar analises quimicas em quatro cultivares de soja Glycine max (L.) Merrill (IAC PL-1; IAC 22; IAC 8-2 E IAC 15-2), bem como os seus respectivos conteudos de ferro soluvel. Os teores de proteina nos graos, que foram em media de 34,46%, foram estatisticamente iguais; o de lipideos foi maior para a cultivar IAC PL-1, com 20,07% (P<0,01) e a cultivar que apresentou o menor teor de fibras foi tambem a IAC PL-1, com 5,24% (P<0,01), no grao moido e tratado termicamente a 95oC por uma hora. A quantidade de ferro total foi maior para a cultivar IAC 8-2, com 110,27 ppm, seguida pela IAC PL-1, que apresentou uma media de 101,93 ppm de ferro. Quanto aos seus conteudos de ferro soluvel e de polifenois, nao houve diferenca estatistica entre os tratamentos, sendo os seus conteudos medios de ferro soluvel cerca de 2,52 mg/100 g , e de tanino cerca de 5,51 mg/100 de soja moida e tratada termicamente. Pelos resultados dessas analises, verifica-se que a soja IAC PL-1 seria a mais indicada para um possivel tratamento de anemia ferropriva de ratos, por ter bons conteudos de ferro total e conteudo de ferro soluvel estatisticamente igual a da soja IAC 8-2, que teve o maior conteudo de ferro total e por apresentar os menores teores de fibras.

Ensaio tecnológico e sensorial de soja [Glycine max (L.) Merrill] enlatada em estádios verdes e no estádio da maturação de colheita

It was investigated the consumption possibility of the soybean cultivar IAC PL-1 canned as green grain and its best harvest time for canning. Five harvests were processed from the 48th day after flowering (DAF) until extinction of the green coloration. The canning procedure started by pod bleaching, dehulling and canning. To the five lots obtained, a sixth lot was added to study the effect of storage. To qualify the six lots of canned grains, measures of weight, color, texture were done, as well as characteristics of canning liquid. Studies of the sensorial properties of canned grains to dimensionate both acceptance and aspect was performed. Canning was optimized to 121oC with sterilization time around four minutes. Grains physiological maturity took place between 61st to 64th DAF. The heat process conserved the green color of canned grains and did not induce significant loss of the mass of grains; the firm texture of grains increased with maturation. The tasters showed good acceptance of the products and there was no preference concerning the maturation stages. The work concluded that green grains of soybean IAC PL-1 provide canned products with very good technical and taste characteristics. It was found that grains harvested at the conventional maturation point stored and canned obtained good taste acceptance, following that the cultivar IAC PL-1 is also suitable to consumption canned after storage.