Three 65"Brix low-pulp concentrated orange juice (COJ) samples, between -19 and 30°C were shear-thinning (pseudoplastic) fluids with negligible magnitudes of yield stress. The simple power law model fit welt the shear rate-shear stress data. For one sample, the Powell-Eyring model also described the data well. The Arrhenius model described the effect of temperature on the apparent viscosity and the consistency index of the power law model. The activation energy of flow (E,) was 10.7 + 0.2 kcal/g mole. The models of Harper and El Sahrigi and Christiansen and Craig were suitable for describing the combined effect of temperature and shear rate. The magnitude of Ea decreased with decrease in concentration. Apparent viscosity and K increased exponeitially with concentration.

Flow behavior of guava puree was determined with a tube viscometer. The puree samples (9.8‐16.0° Brix) exhibited shear‐thinning behavior. The flow behavior index of the power law model was nearly constant for all the samples over a temperature range of 25‐60°C; its mean value was 0.43 with a standard deviation of 0.031. The apparent viscosity decreased with increase in temperature and the activation energy offlow was found to be 3.7 kcallg mole. The apparent viscosity increased as the concentration of the purees was increased; the increase was proportional to concentration raised to a power of 2.7. The Mizrahi‐Berk model described well the flow data of the purees. The magnitude of the shear rate exponent was about 0.48, indicating that the purees were suspensions in shearthinning media.

ResumoO coco babaçu (Orbignya speciosa) é constituído por quatro partes. Epicarpo, mesocarpo, endocarpo e amêndoas. Atualmente o coco babaçu é coletado e descascado manualmente por mulheres e crianças, sendo um dos problemas sociais da região Nordeste/Norte do Brasil. O trabalho de pesquisa teve como objetivo desenvolver um processo de descascamento adequado para o coco. Foram feitas caracterizações quanto ao volume, massa, densidade real, comprimento, perímetro transversal e distância entre o epicarpo e a amêndoa. Estes dados foram analisados, estabelecendo relações entre a quantidade de amêndoas encontradas em cada coco e as médias dos valores dos parâmetros estudados. Seis experimentos foram realizados com o objetivo de verificar a força de compressão necessária para a sua quebra, sendo analisado no coco in natura; descascado por abrasão; seco a 120 °C; seco a 120 °C e descascado por abrasão; seco a 120 °C descascado por abrasão, hidratado e congelado a -18 °C; e seco a 120 °C, descascado por abrasão, hidratado e "puffing" (Expansão). No procedimento de descascamento, verificouse o tempo médio para a retirada do epicarpo e mesocarpo, e na secagem e hidratação o tempo de estabilização da massa. Palavras-chave: babaçu; descascamento; amêndoas; pré-tratamento; compressão. AbstractThe babassu nut (Orbignya speciosa) consists of fours parts: the epicarp, mesocarp, endocarp and kernel. Currently the babassu nut is collected and cracked manually by women and children, which is one of the social problems of the Brazil's North/Norwest region. The purpose of this work was to develop an effective technique for removing the shell of the babassu nut. Characterizations were made of the volume, mass, real density, length, transversal perimeter and distance between the epicarp and the kernel. These data were analyzed to establish a correlation between the amount of kernels in each babassu nut and the average of the values of the parameters under study. To determine the compressive force required to break babassu nuts, six experiments were carried out involving: a) untreated nuts; b) nuts peeled by abrasion; c) nuts dried at 120 °C; d) dried at 120 °C and peeled by abrasion; e) dried at 120 °C peeled by abrasion, hydrated and frozen at -18 °C; and f) dried at 120 °C, peeled by abrasion, hydrated and puffed. An estimate was made of the average time required to remove the epicarp and mesocarp in the shelling procedure, and of the time required to reach mass equilibrium in the drying and hydration procedure. Keywords: babassu; nut breaking; kernels; compression; pretreatment. Tecnologia de quebra do coco babaçu (Orbignya speciosa) Babassu nut breaking techniqueMarcia Paisano SOLER 1 *, Alfredo de Almeida VITALI 1 , Eric Fumhio MUTO 1 IntroduçãoO babaçu é uma palmeira monocaule, com até 20 m de altura e estipe liso medindo até 41 cm de diâmetro, frutos oblongos-elipsóides lisos, com 11,3 x 6,3 cm de diâmetro, de coloração marrom na maturidade 3 . A época de frutificação do babaçu ocorre durante o ano todo, sendo que o pico da pro...

a b s t r a c tIn the present study, Coffea arabica was artificially contaminated with spores of toxigenic Aspergillus westerdijkiae. The contaminated coffee was roasted in a vertical spouted bed roaster at four different temperatures (180°C, 200°C, 220°C and 240°C) and three different time periods (5, 8 and 12 min), in order to obtain more accurate results for the development of the kinetic model for ochratoxin A (OTA). Chlorogenic acids (CGA) content during coffee roasting was also evaluated to investigate the effect of the heat employed to destroy OTA in these health promoting compounds. Coffee treated with spouted bed roasting significantly reduced the OTA level from 8% to 98%. The spouted bed roasting proved to be a very efficient procedure for OTA reduction in coffee, and its reduction depended directly on the degree of roasting. OTA degradation during coffee roasting followed first order reaction kinetics. Using the apparent activation energy of OTA degradation and the temperature-dependent reaction rate, there was a compliance with the Arrhenius equation. This model was capable of predicting the thermal induced degradation of OTA and may become an important predicting tool in the coffee industry. The present study was also able to propose roasting conditions appropriate to destroy OTA and maintain most of the CGA at the same time.

65"Brix serum samples from four concentrated orange juice (COJ) samples, between -19 and 30aC, were mildy shear-thinning fluids with negligible yield stress. The power law model described well the flow data. For one sample, the Powell-Eyring model also described the data. The activation energy of flow (E,) for the samples was between 11.2-13.6 kcaI/gmole. The power law parameters were determined for a 65'Brix sample as a function of pulp content (O-11%) between -19 and 30°C. At a fixed temperature, the apparent viscosity and the consistency index increased exponentially with pulp content. E, decreased with increase in pulp content and reached a constant value of about 10.2 kcaI/gmole. Data on a highpulp (21.2%), 65OBrix, sample indicated the presence of yield stress, particularly at low temperatures. The Mizrahi-Berk model predicted reliable values of the yield stress.

The migration of patulin in apples was studied. A patulin-producing Penicillium expansum strain, isolated from apples, was inoculated in sound apples. Patulin was extracted and its migration was studied in each centimeter from the point of inoculation. Trimming just the rotten tissue was not enough to exclude all patulin. At 1 cm from the periphery of the rotten area, no patulin could be detected.

Performance of thermal process simulation software was tested for predicting internal product temperature and lethality. Responses were tested for process deviations on canned products with a wide range of heating characteristics for computer-based on-line control of retorts. Static and agitated processes were tested with products exhibiting heating rate factors (fh) ranging from 2 to 70 min. Cans were fitted with thermocouples and subjected to deviations of various types. Center temperature profiles and lethalities predicted by the model in response to dynamic retort temperatures were compared with those measured by thermocouples. Profiles agreed, and process lethalities calculated from predicted and measured profiles agreed ±10% with the model slightly underpredicting measured lethality.

Resumo -O objetivo deste trabalho foi recuperar e fracionar as proteínas do soro de leite por meio da técnica de coacervação, utilizando o polissacarídeo carboximetilcelulose sódica (CMC). O soro de leite foi obtido da fabricação industrial do queijo tipo frescal. Foram estudados concentrações do polímero (0,1% a 0,9% CMC p/v) e valores de pH, a fim de se obter uma precipitação seletiva das proteínas do soro de leite, sendo as condições otimizadas para produção em piloto. Mediante ajuste gradual, foi possível obter, no pH 3, uma precipitação das proteínas totais (PT/CMC); no pH 4, da β-lactoglobulina (β-Lg/CMC) e, no pH 3,2, a maior proporção de α-lactoalbumina (α-La/CMC). Os coacervados foram separados, por aplicação de força centrífuga, e caracterizados em relação à composição centesimal e perfil eletroforético. O maior rendimento foi verificado no fracionamento da β-lactoglobulina, com 86% de recuperação dessa classe de proteínas do soro desnatado. O coacervado β-lactoglobulina-CMC (β-Lg/CMC) apresenta maior conteúdo protéico, provavelmente em conseqüência da proporção estabelecida entre os hidrocolóides coacervados. O coacervado composto pela α-La/CMC apresentou menor conteúdo protéico e porcentagem de recuperação dessas proteínas presentes no soro.Termos para indexação: carboximetilcelulose, β-lactoglobulina, α-lactoglobulina, hidrocolóides coacervados. Milk whey protein recuperation by coacervation with polysaccharideAbstract -This work aimed to recover and fractionate milk whey proteins through the coacervation technique, using sodium carboxymethyl cellulose (CMC) polysaccharide. Milk whey was obtained from the manufactured cheese type "frescal". Polymer concentration (0.1-0.9% CMC w/v) and pH values were studied in order to obtain a selective precipitation of whey proteins; conditions were optimized to pilot scale production. After pH gradual adjustment the precipitation of total proteins (PT/CMC) was achieved for pH 3; for pH 4 β-lactoglobulin (β-Lg/CMC) precipitation and for pH 3.2 the greatest proportion of α-lactoalbumin (α-La/CMC) precipitation. Coacervates were separated by centrifuge force, and characterized in relation to their composition and electrophoretic profile. The highest yield was obtained from fractionation of β-Lg/CMC with precipitation of 86% of this whey protein type. Highest protein content was showed by β-Lg/CMC, probably due to the proportion among hydrocolloids. The α-La/CMC showed minor protein content and yield recuperation of this whey protein fraction.