Some Physicochemical And Nutritional Properties Of A Sweet Lupin (lapinus Albus Var. Multolupa) Protein

The lupin variety utilized in this study contained between 38-40% crude protein on a dry basis. The proteins were 55% soluble in water and 80-85% soluble in aqueous alkaline solution at pH 9.0. The pH of lowest solubility was 4.5. Fractionation of the alkaline extract by gel filtration on Sephadex G-100 gave three elution peaks. Sucrose gradient centrifugation furnished three bands with sedimentation coefficients of 8.1, 2.8, and 1.2 S, and the calculated molecular weights (mol wt) were 163 000, 53 000, and 9000, respectively. Electrophoresis on polyacrylamide gel revealed six protein bands. When the sample was treated with mercaptoethanol and sodium dodecyl sulfate (SDS) and the gel prepared in the presence of SDS, a maximum of 11 polypeptide monomers was detected ranging in molecular weight from 5500 to 66 000. Methionine was the first limiting amino acid and addition of 0.15% DL-methionine based on the protein raised the protein efficiency ratio from 0.9 to 2.2 for the rat. © 1978 American Chemical Society.2661438144

Polyphenol Oxidase from Spanish Hermaphrodite and Female Papaya Fruits (Carica papaya Cv. Sunrise, Solo Group)

A partial characterization of polyphenol oxidase (PPO) in papaya fruits is described in this work. Differences among papaya fruits from hermaphrodite and female flowers in terms of PPO activity are also presented. Total soluble PPO activity in female fruits was higher than in hermaphrodite fruits during all ripening proccesses, and greater PPO values were obtained from green papayas. In this ripening stage, female fruits exhibited 30% more PPO activity than hermaphrodite fruits. Specific PPO activity also underwent this evolution. Female green papayas showed a significantly higher PPO activity. This difference became insignificant in ripe fruits (10 days at 14 °C). Native PAGE experiments showed the presence of six PPO isoenzymes in hermaphrodite papayas whereas PPO from female fruits separated into only four bands (revealed with 0.003 M gallic acid). Assays of incubation with 0.003 M gallic acid followed by ethanolic washings produced a slightly different PPO pattern (five PPO active bands for hermaphrodite green fruits and four PPO active bands for female green ones). Through ripening, the PPO isoenzyme pattern did not undergo significant changes; only a band (Rf = 0.28) disappeared in the PPO extracts of mature-green, ripe, and overripe hermaphrodite fruits.Peer Reviewe

Sampling Plan For The Brazilian Taco Poject

The TACO project (Brazilian Table of Food Composition), sponsored by the Brazilian Ministry of Health and executed by NEPA-UNICAMP (Center for Studies and Research on Foods-State University of Campinas), is generating new data on the most consumed foods in Brazil, based on a national sampling plan and analyses carried out by laboratories with demonstrated laboratory capability in nutrient analysis. Key foods have been chosen according to a national multicentric survey of food consumption, starting with 200 food items. The sampling plan covers nine cities in the five official Brazilian geopolitical regions (North, Northeast, South, Southeast and Centralwest), corresponding to approximately 16.8 million inhabitants out of a total Brazilian population of about 170 million. Samples of principal brands (maximum of five for each food) are collected from supermarkets/hypermarkets where 84-85% of total food purchases are made by the Brazilian population. Two units of each principal brand of each product are taken at each sampling site. The total units for each food from all regions are mixed and packed in cans, and three final composites of 100-200 g for each food are sent for analyses in approved laboratories. © 2002 Elsevier Science Ltd. All rights reserved.154499505Cohran, W.G., Sampling Techniques (1977), John Wiley & Sons, New YorkDomene, S.M.A., Lima, D.M., Padovani, R.M., Lajolo, F.M., Taddei, J.A.A.C., Galeazzi, M.A.M., TACO project-Brazilian food composition database (1999), Paper presented at the Third International Food Data Conference, RomeFranco, G.V.E., (1982) Nutrição: Texto Básico e Tabela de Composição Quimica dos Alimentos, , 6th edn. Atheneu, São PauloGaleazzi, M.A.M., Domene, S.M.A., Sichieri, R., Estudo multicêntrico sobre consumo alimentar (1997) Caderno de Debates, pp. 1-62. , (Eds.) special volumeGaleazzi, M.A.M., Domene, S.M.A., Zabotto, C., Inquérito de consumo alimentar familiar de Belém (1998), Relatório Ténico para o Centro Colaborador da Região Norte, Ministério da SaúdeGaleazzi, M.A.M., Falconi, P.J., (1998), Inquérito de consumo alimentar familiar (INCAF) de Brasília. Relatório Técnico para Secretaria de Saúde do DF(1977), IBGE. Estudo Nacional de Despesa Familiar-ENDEF: Tabela de Composição de Alimentos. Instituto Brasileiro de Geografia e Estatística, Rio de Janeiro(2000), http://www.ibge.gov.br, IBGE. Instituto Brasileiro de Geografia e Estatística. Retrieved June 3, 2002 from the World Wide Web: Censo DemográficoPehrsson, P.R., Haytowitz, D.B., Holden, J.M., Perry, C.R., Beckler, D.G., USDA's national food and nutrient analysis program: Food sampling (2000) J. Food Comp. Anal, 13, pp. 379-389Rodriguez-Amaya, D.B., Colugnati, F.A.B., Padovani, R.M., Lima, D.M., Galeazzi, M.A.M., Evaluation of the laboratory capability in Brazil (2001), Paper presented at the Fourth International Food Data Base Conference, BratislavaSouza, R.A.M., de Silva, R.O.P., Mandelli, C.S., Tasco, A.M.P., Comercialização hortícola: Análise de alguns setores do Mercado varejista de São Paulo (1998) Inform. Econ, 28, pp. 7-23(2001) Tabela Brasileira de Composição de Alimentos, , http://www.fcf.usp.br/tabe, USP. Universidade de São Paulo. Retrieved on June 4, 2002 from the World Wide We

Influence of controlled atmosphere storage on polyphenoloxidase activity in relation to colour changes of minimally processed ‘Jonagored’ apple

The effects of the storage atmosphere composition (2% O2 + 4% CO2; 2% O2 + 8% CO2; 2% O2 + 12% CO2) on polyphenoloxidase activity and phenolic content of the ‘Jonagored’ apple variety during cold storage was evaluated, and the relationship with enzymatic browning investigated. Controlled atmosphere storage inhibited the polyphenoloxidase (PPO) activity of apple cubes during storage. It seems that the higher the concentration of carbon dioxide in the storage atmosphere the higher inhibition of PPO and the lower browning achieved. At the substrate-enzyme levels investigated, the phenolic content, substrate level was the major factor determining darkening

Avaliação da atividade dos inibidores de tripsina após digestão enzimática em grãos de soja tratados termicamente Evaluation of trypsin inhibitors activity after enzymatic digestion in heat-treated soybean

Este trabalho avalia a reativação dos inibidores de tripsina, após proteólise in vitro, de grãos de soja tratados termicamente. Para a inativação térmica dos inibidores, os grãos foram embebidos em água destilada (1:5 p/v) durante 12 horas e aquecidos em placas sob refluxo por 30 minutos. A reativação dos inibidores foi avaliada em comparação com a atividade das amostras cruas e aquecidas. A digestibilidade in vitro das proteínas variou de 47% ('OC-13') a 59% (Paraná), apresentando uma melhora, em média, de 32,6% com o aquecimento. A atividade dos inibidores de tripsina para os grãos crus variou de 122 a 206 UTI/mg de amostra, e os valores correlacionaram-se negativamente com a porcentagem de digestibilidade (r = -0,9177). Os inibidores tiveram suas atividades totalmente inativadas com o aquecimento dos grãos, os quais apresentaram porcentagem de recuperação, em média, de 40%. Com o aquecimento, a inativação dos inibidores provavelmente ocorre por complexação com os componentes do grão, o que leva à recuperação da atividade com o processo de digestão enzimática.<br>This work evaluates the trypsin inhibitors reactivation, after in vitro proteolysis, of heat-treated soybean. For the inhibitors thermal inactivation, soybeans were soaked in distilled water (1:5 p/v) during 12 hours and heated on reflux plates for 30 minutes. The inhibitors reactivation was evaluated in comparison with the activity of raw and heated samples. The in vitro digestibility of proteins ranged from 47% ( 'OC-13') to 59% ('Parana'), showing an average progress of 32.6% with the heating. The trypsin inhibitors activity ranged from 122 to 206 UTI/mg for the raw sample, and the values correlated negatively with the digestibility percentage (r = - 0.9177). The inhibitors had the activities totally inactivated with the heating of soybeans, which showed an average recovering percentage of 40%. With the heating, the inactivation of inhibitors probably takes place by complexing with the soybean components, which leads to the recovering of activity with the enzymatic digestion process