Obtenção de isotermas de dessorção de cogumelo in natura e desidratado osmoticamente

O presente trabalho teve como objetivo a obtenção de isotermas de dessorção de cogumelo Agaricus blazei nas formas in natura e desidratada osmoticamente com solução de NaCl (10% p/p) a 20°C. As isotermas foram determinadas nas temperaturas de 40, 60 e 80°C, através do método gravimétrico estático com soluções salinas saturadas. Os dados experimentais foram ajustados a cinco modelos da literatura (BET, GAB, Halsey, Henderson e Oswin) e a dois modelos com o parâmetro temperatura (Henderson modificado e Chung-Pfost). O desvio relativo médio entre os valores experimentais e os valores preditos foi calculado para cada curva para se avaliar o modelo que apresentou melhor ajuste. Assim, observou-se que os modelos de Henderson e Henderson modificado foram os que melhor se ajustaram dentre as equações sem e com o parâmetro temperatura tanto para o cogumelo in natura quanto para o desidratado osmoticamente.

Isotermas e calor isostérico de sorção do feijão

O teor de água de equilíbrio dos grãos de feijão foi determinado pelo método dinâmico-gravimétrico para temperaturas entre 25 e 55 °C e atividades de água para cada temperatura, entre 0,20 e 0,75. Observou-se que o teor de água decresce com o aumento da temperatura para uma dada atividade de água à semelhança dos produtos higroscópicos. Aos dados experimentais foram ajustados diversos modelos matemáticos disponíveis na literatura (Brunauer-Emmett-Teller, Chung Pfost, Copace, Guggenhein-Anderson-de Boer, Halsey Modificado, Henderson, Henderson Modificado, Oswin, Sabbah e Sigma Copace). Segundo os parâmetros estatísticos de análise, o modelo de Halsey Modificado foi o que descreveu melhor a higroscopicidade do feijão. A partir dos resultados obtidos calculou-se o calor isostérico para cada teor de água de equilíbrio. Observou-se que o calor isostérico aumenta com a diminuição do conteúdo de água do produto, indicando que a redução do teor de água aumenta a energia necessária para a remoção de água. Os valores de calor isostérico para os grãos de feijão na faixa de umidade de 10,10 a 21,71 (% b.s.), variam de 3961 a 2718 kJ kg-1.

Otimização da secagem do malte de Zea mays

Neste trabalho foi feita a otimização do processo de secagem do malte de milho (Zea mays) com o objetivo de gerar um derivado de alto valor comercial sem reduzir a atividade das enzimas presentes neste, alfa e beta - amilases, e tentar agregar valor à cultura do milho. Modelos de curvas de secagem foram usados para simular as isotermas de secagem. Um planejamento fatorial completo do tipo 2² foi feito, usando como fatores o tempo (5,18; 6; 8; 10 e 10,8 h) em torno do tempo de secagem para determinação de umidade em alimento e a temperatura (54, 65 e 76 °C) próxima do ótimo das enzimas e a atividade enzimática no malte como resposta. O modelo que mais se ajustou aos dados de cinética de secagem foi o de Henderson e Henderson, e a umidade média retirada do malte foi maior que 40%. A otimização da secagem indicou que se deve operar o secador na região que se aproxima dos 54 °C e da faixa de 5,18 a 6 h de processo. O malte obtido possuiu um bom potencial enzimático, sendo possível assim, contribuir para a agregação de valor à cultura do milho.

Moisture adsorption characteristics of ginger slices

The moisture adsorption characteristics of dried ginger slices was studied to determine the effect of storage conditions on moisture adsorption for the purpose of shelf life prediction, selection of appropriate packaging materials, evaluate the goodness-of-fit of sorption models, and determine the thermodynamics of moisture adsorption for application in drying. There was a highly significant effect (p < 0.05) of water activity (a w), temperature, and pre-treatment on the equilibrium moisture content (EMC) of the dried ginger slices. At constant a w, the EMC decreased as temperature increased. The EMC of all samples increased as the a w increased at constant temperature. The sorbed moisture of the unpeeled ginger slices was higher than the peeled while those of unblanched samples were higher than the blanched. Henderson equation allows more accurate predictions about the isotherms with the lowest %RMS, and therefore, it describes best the adsorption data followed by GAB, Oswin, and Halsey models in that order. The monolayer moisture generally decreased with temperature for all samples. The isosteric heat decreased with moisture content approaching the asymptotic value or the latent heat of vaporization of pure water (∆Hst = 0) while the entropy of sorption was observed to increase with moisture content.

Application of mathematical models for the prediction of adsorption isotherms in solid mixture for mango powder refreshment

Solid mixtures for refreshment are already totally integrated to the Brazilian consumers' daily routine, because of their quick preparation method, yield and reasonable price - quite lower if compared to 'ready-to-drink' products or products for prompt consumption, what makes them economically more accessible to low-income populations. Within such a context, the aim of this work was to evaluate the physicochemical and mineral composition, as well as the hygroscopic behavior of four different brands of solid mixture for mango refreshment. The BET, GAB, Oswim and Henderson mathematical models were built through the adjustment of experimental data to the isotherms of adsorption. Results from the physiochemical evaluation showed that the solid mixtures for refreshments are considerable sources of ascorbic acid and reductor sugar; and regarding mineral compounds, they are significant sources of calcium, sodium and potassium. It was also verified that the solid mixtures for refreshments of the four studied brands are considered highly hygroscopic.

Effect of air-temperature and diet composition on the drying process of pellets for japanese abalone (Haliotis discus hannai) feeding

The aim of this research was to study the effect of air-temperature and diet composition on the mass transfer kinetics during the drying process of pellets used for Japanese Abalone (Haliotis discus hannai) feeding. In the experimental design, three temperatures were used for convective drying, as well as three different diet compositions (Diets A, B and C), in which the amount of fishmeal, spirulin, algae, fish oil and cornstarch varied. The water diffusion coefficient of the pellets was determined using the equation of Fick's second law, which resulted in values between 0.84-1.94×10-10 m²/s. The drying kinetics was modeled using Page, Modified Page, Root of time, Exponential, Logarithmic, Two-Terms, Modified Henderson-Pabis and Weibull models. In addition, two new models, referred to as 'Proposed' models 1 and 2, were used to simulate this process. According to the statistical tests applied, the models that best fitted the experimental data were Modified Henderson-Pabis, Weibull and Proposed model 2, respectively. Bifactorial analysis of variance ANOVA showed that Diet A (fishmeal 44%, spirulin 9%, fish oil 1% and cornstarch 36%) presented the highest diffusion coefficient values, which were favored by the temperature increase in the drying process.

Moisture sorption isotherms of fresh and blanched pumpkin (Cucurbita moschata)

Moisture desorption isotherms of fresh and heat blanched pumpkins (Cucurbita moschata) were determined at three temperatures (30, 50 and 70 °C), using the standard, static-gravimetric method. The GAB, Oswin, BET, Halsey, and Henderson models were tested and, with the exception of the Henderson model, showed satisfactory fits to the experimental data. The GAB model was used to analyze the fitting ability to describe the isotherm type. The shape of the desorption isotherms of fresh and blanched pumpkin at 30 and 50 °C was intermediate to types II and III, and at 70 °C it was of type II for the blanched pumpkin and close to type II for the fresh sample. The influence of blanching on the decrease in equilibrium moisture was very small compared to the fresh samples and it was related to the loss of soluble solids during the pre-treatment. The isosteric heat of sorption measures indicated that a larger amount of heat was required to remove the water from the fresh samples than from the blanched ones.

Creating SHAREDVALUE: A How-to Guide for the New Corporate (R)evolution

Competitividad y valor compartido

2004-05 Board of Trustees

The 2004-2005 Board of Trustees. Pictured here from left to right are: Front Row - Val Fleming; Dr. Patricia Teal; Wendy Staff; Dr. Norris Walker, Chair; Dr. David Atkinson, President and Vice Chancellor; Dr. Val Jaeger; Donna Scott; and Steven Lalinovich. Middle Row - Mike Farrell, Secretary to the University; Rudi Kroeker; Brandon Larry, President, Brock University Students' Union; Dr. Terry Boak, Vice-President, Academic and Provost; Mitzi Banders; Geeta Powell; Dr. Sid Segalowitz; Tom Gauld; Karin Jahnke-Haslam; and Dr. Mohammed Dore. Back Row - David Edwards, Immediate Past Chair; Bruce Wormald; Willy Heldbuechel, Vice-Chair; Brad Clarke; David Howes, Vice-Chair; Mark Steinman; Peter Partridge; Michael Sidenberg; Angelo Nitsopoulos; Steven Pillar, Vice President, Finance and Administration; Ron Dubien, Chief Information Officer. Absent from photo - Dr. Raymond Moriyama, Chancellor; Eleanor Ross; Jagoda Pike; Dr. Mary Frances Richardson; and Nick Brown.

President's Portrait

On Tuesday, February 10th, 1970, Chairman of the Board, D. Whiting Lathrop presented a portrait of Dr. Gibson to the University. The plaque reads: Dr. James A. Gibson First President and Vice Chancellor of Brock University by Ian Henderson Artist in Residence 1969-1970 Presented to the University by the Board of Governors February 1970 The portrait hung in Dr. Gibson's waiting room until the end of his presidency where it was relocated to H-Block in MacKenzie Chown.

1998 Brock Baseball Team

1998 Brock Badger men's baseball team photo. Front Row (L to R): Bill Gillen, Ryan Villers, Greg Arbour, Mark Cheeseman, Andrew Tinnish, Rick Bottomley, Matt Fletcher, Brad Namtzu, Darryl Presley, Dan Pino, Grant Giffen, Mike Caruso, Mark Reilly Back Row (L to R): Jeff Lounsbury (Head Coach), Jayar Green, Creston Rudolph, Ryan Fisher, Jamie Trull, Stefan Strecker, Andrew Robb, Jeremy Walker, Ryan Johns, Matt Stezycki, Steve Lester, Fabio Del Rio, Jarrod Haase, Jess Dixon, Rick Falconer (Pitching Coach) Absent: Marc Purdy, Ian Bala, Marc LePage (Asst. Coach), Waybe Briggs-Jude (Asst. Coach)

Men's Basketball Team

1981-1982 Men's Basketball Team Front - Doug Fast. John Radaslav, Jim Zareski, Kelly Baker, Jim Baldin, Doug Johnson, Tim Mcalpine Back - Manager Britt Fischer, ??, Bob Blasko, David Hodges, Mark Green, Bob Yuhasz, Paul Treitz, Mike Creighton, Trainer Joe Kenney, Coach Garney Henley

1969-70 Men's Basketball

Pictured here from left to right: Back Row - Les Korchok (Coach), Ken Cripps, Mike McGinnis, Bill Butler, Tim McKillop, Gary Jellum, Fred Kovacs (Manager). Front Row - Jim Leach, Wally Dick, Bob Tatti, Paul Zutautas, Tom Kearney (Trainer). Kneeling - Dave Luff, Dave Brent. Missing - Bill Levesque.

1971-72 Varsity Curling

Pictured here from left to right are: Front - John Donald, Greg Reid, Steve Thomas, John Glennie, and Mike Wilder. Back - Ed Davis (Coach). The 1971-72 curling team boasted a number of achievements including being the Niagara Distrcit Major Champions, University of Toronto Bonspiel Champions, and the Ontario University Athletic Association Champions.