Effects of Pretreatments with Ethanol and Ultrasound on Convective Drying of BRS Vitória Grapes

The objective of this study was to evaluate the effect of ethanol and ultrasound as pretreatment to improve the convective drying of the BRS Vitória grape. The drying kinetics, rehydration, quality parameters, and phenolic compounds were evaluated. Before drying, grapes cv. BRS Vitória was ultrasound treated using two separate means, with ethanol (99.5% v/v) and distilled water. After pretreatment, the grapes were dried at 60°C and 0.1 m/s. The Logarithmic model provided a better prediction to describe the drying of grapes. Peleg’s model showed satisfactory adjustments to predict rehydration. Compared to the Control, pretreatment using the combination of ultrasound and ethanol decreased the drying time of the grapes by 61%. The pretreatments did not influence in quality parameters. In contrast, phenolic retention was observed in samples with ethanol. These results open new perspectives on the drying process and product quality by combining ethanol and ultrasound

Desidratação osmótica de batata-doce (Ipomoea batatas) em soluções ternárias

The aim of this work was to evaluate the osmotic dehydration of sweet potato (Ipomoea batatas) using hypertonic sucrose solutions, with or without NaCl, at three different concentrations, at 40 °C. Highest water losses were obtained when the mixture of sucrose and NaCl was used. The addition of NaCl to osmotic solutions increases the driving force of the process and it is verified that the osmotic dehydration process is mainly influenced by changes in NaCl concentration, but the positive effect of the salt-sucrose interaction on soluble solids also determined the decrease of solid gain when solutes were at maximum concentrations. Mass transfer kinetics were modeled according to Peleg, Fick and Page's equations, which presented good fittings of the experimental data. Peleg's equation and Page's model presented the best fitting and showed excellent predictive capacity for water loss and salt gain data. The effective diffusivity determined using Fick's Second Law applied to slice geometry was found to be in the range from 3.82 x 10-11 to 7.46 x 10-11 m²/s for water loss and from 1.18 x 10-10 to 3.38 x 10-11 m²/s for solid gain.O objetivo deste trabalho foi avaliar a desidratação osmótica da batata-doce (Ipomoea batatas) utilizando soluções hipertônicas de sacarose e/ou NaCl, em três concentrações diferentes a 40 °C. As perdas de água mais elevadas foram obtidas quando se utilizou a mistura de sacarose e NaCl. A adição do NaCl às soluções osmóticas aumenta a força motriz do processo. Verifica-se que o processo de desidratação osmótica é principalmente influenciado pela mudança da concentração de NaCl, mas o efeito positivo da interação do sal com a sacarose também determinou a diminuição do ganho de sólidos quando os solutos estavam em concentrações máximas. As cinéticas de transferência de massa foram modeladas de acordo com as Equações de Peleg, de Fick e de Page, e apresentaram bons ajustes aos dados experimentais. A Equação de Peleg e o modelo da Page apresentaram os melhores ajustes e mostraram uma excelente capacidade de predição para dados de ganho de sólidos e de perda de água. A difusividade efetiva foi determinada utilizando-se a Segunda Lei de Fick aplicada à geometria de placa plana, encontrando valores de 3,82 x 10-11 a 7,46 x 10-11 m²/s para a perda de água, e de 1,18 x 10-10 a 3,38 x 10-11 m²/s para o ganho de sólidos.696701Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Utjecaj prethodne obrade ultrazvukom na sušenje dinje i modeliranje temperaturnog profila pomoću računalne dinamike fluida

Research background: Drying is one of the most traditional processes of food preservation. Optimizing the process can result in a competitive product on the market regarding its price and quality. A common method in use as a pretreatment to drying is ultrasound. The goal of this work is to analyze different drying methods with and without applying ultrasound (US) pretreatment, on heat and mass transfer, simulating numerically the temperature profile by computational fluid dynamics (CFD). Experimental approach: The melon slices were pretreated with ultrasound for 10 (US10), 20 (US20) and 30 (US30) min at 25 kHz, and the water loss and solid gain were evaluated. Samples were dried at different temperatures (50, 60 and 70 °C). The effective diffusivity was estimated, and experimental data were modelled using empirical models. The airflow in the dryer and the temperature profile in the melon slice were simulated via computational fluid dynamics (CFD). Results and conclusions: Ultrasound pretreatment reduced the drying time from 25% (samples US20 and US30 at 50 °C) to 40% (samples US20 and US30 at 70 °C). The two-term exponential model presented the best fit to the experimental data, and the diffusivity coefficients showed a tendency to increase as the time of exposure of the melon to ultrasonic waves increased. Pretreatment water loss and solid gain behaviour and drying kinetic and diffusion data were used to choose the best experimental conditions to be simulated with CFD. The heat transfer modelling through CFD showed that the temperature distribution along the melon slice was representative. Therefore, the profile obtained via CFD satisfactorily describes the drying process. Novelty and scientific contribution: The use of simulation tools in real processes allows the monitoring and improvement of existing technologies, such as food drying processes, that involve complex mechanisms, making it difficult to obtain some data. Application of CFD in the drying processes of fruits and vegetables is still very recent, being a field little explored. There is no record in the literature that uses CFD in the drying of melon.Pozadina istraživanja. Sušenje je jedan od najtradicionalnijih postupaka konzerviranja hrane. Optimiranjem postupka sušenja dobivaju se proizvodi koji su cijenom i kakvoćom konkurentni na tržištu. Primjena ultrazvuka je uobičajena metoda prethodne obrade proizvoda prije sušenja. Svrha je ovoga rada bila ispitati različite metode sušenja s prethodnom obradom ultrazvukom ili bez nje na prijenos topline i mase, te napraviti simulaciju temperaturnog profila primjenom računalne dinamike fluida. Eksperimentalni pristup. Kriške dinje su prethodno obrađene ultrazvukom pri 25 kHz tijekom 10, 20 i 30 min, te su izmjereni gubitak vode i povećanje mase suhe tvari uzoraka. Uzorci su zatim sušeni pri temperaturama od 50, 60 i 70 °C. Procijenjena je efektivna difuzivnost vode, a eksperimentalni su rezultati oblikovani pomoću empirijskih modela. Protok zraka u sušari i promjena temperature u krišci dinje simulirani su pomoću računalne dinamike fluida. Rezultati i zaključci. Prethodnom obradom ultrazvukom vrijeme se sušenja smanjilo od 25 % (za uzorke obrađene ultrazvukom tijekom 20 i 30 min, a zatim sušene na 50 °C) do 40 % (za uzorke obrađene ultrazvukom tijekom 20 i 30 min, a zatim sušene na 70 °C). Dvočlani eksponencijalni model najbolje je opisao eksperimentalne podatke, a koeficijent difuzivnosti povećavao se s produljenjem obrade uzoraka dinje ultrazvukom. Gubitak vode i povećanje mase suhe tvari tijekom prethodne obrade ultrazvukom, te kinetika sušenja i podaci o difuzivnosti korišteni su za odabir najboljih eksperimentalnih uvjeta i njihovu simulaciju pomoću računalne dinamike fluida. Modeliranjem prijenosa topline potvrđeno je da je distribucija topline u kriški dinje bila u skladu s očekivanjima. Stoga je zaključeno da temperaturni profil dobiven računalnom dinamikom fluida na zadovoljavajući način opisuje postupak sušenja. Novina i znanstveni doprinos. Alati za simulaciju stvarnih procesa omogućuju praćenje i poboljšanje postojećih postupaka obrade hrane kao što je sušenje, koje uključuje kompleksne mehanizme, što otežava dobivanje podataka. Primjena računalne dinamike fluida pri sušenju voća i povrća je noviji i slabo istražen postupak. U znanstvenoj literaturi nema podataka o upotrebi računalne dinamike fluida pri sušenju dinje

The applicability of the Baudoin Index for sex estimation in Brazilian skulls / A aplicabilidade do Índice Baudoin para estimativa de sexo em crânios Brasileiros

Introduction: The Baudoin Index (BI) is a human identification method for sex estimation based on occipital condyle measures. Objective: To investigate the applicability of the BI for sex estimation in a Brazilian sample. Material and Method: This was a blind cross-sectional study with 209 skulls from the Center for Studies in Forensic Anthropology, Pernambuco School of Dentistry, University of Pernambuco (CEAF / FOP / UPE). The right and left occipital condyles were measured for width and length using a digital caliper. Subsequently, the BI formula was applied to the measurements for classification of sex. The data were analyzed descriptively and by Student’s t test, Mann Whitney test, and Pearson’s Chi square, considering a 5% significance level. Results: The occipital condyle measures showed significant sex-related differences (P < 0.05), except for the width of the right occipital condyle (P = 0.376). The agreement rates of the BI in males (38%, right side; 29.6%, left side) were lower than those in females (59.4%, right side; 52.5%, left side). Conclusion: The Baudoin Index did not show accurate sex estimates in the Brazilian sample of skulls analyzed herein. Thus, this index is not suitable for estimating sex in this population.Introduction: The Baudoin Index (BI) is a human identification method for sex estimation based on occipital condyle measures. Objective: To investigate the applicability of the BI for sex estimation in a Brazilian sample. Material and Method: This was a blind cross-sectional study with 209 skulls from the Center for Studies in Forensic Anthropology, Pernambuco School of Dentistry, University of Pernambuco (CEAF / FOP / UPE). The right and left occipital condyles were measured for width and length using a digital caliper. Subsequently, the BI formula was applied to the measurements for classification of sex. The data were analyzed descriptively and by Student’s t test, Mann Whitney test, and Pearson’s Chi square, considering a 5% significance level. Results: The occipital condyle measures showed significant sex-related differences (P < 0.05), except for the width of the right occipital condyle (P = 0.376). The agreement rates of the BI in males (38%, right side; 29.6%, left side) were lower than those in females (59.4%, right side; 52.5%, left side). Conclusion: The Baudoin Index did not show accurate sex estimates in the Brazilian sample of skulls analyzed herein. Thus, this index is not suitable for estimating sex in this population.

Utjecaj prethodne obrade etanolom i ultrazvukom na sušenje ananasa u konvekcijskoj sušari

Research background. Drying represents a viable unit operation for the preservation of food. Convective drying is the most used method for plant materials. However, it can result in negative changes in food nutrient composition, and other quality parameters, besides requiring high energy consumption. Pretreatments can represent an alternative to minimise these negative aspects of dried materials. This work aims to evaluate the use of ethanol and ultrasound before pineapple convective drying and its effect on the product´s colour, water activity, ascorbic acid and total carotenoid contents. Experimental approach. For the pretreatment step, fruit samples were immersed in ethanol solutions of different volume fractions, and experiments were carried out for 10 min with and without using ultrasound (25 kHz). Fruit samples were dried at 60 ºC. A control group (without the pretreatment step) was also dried under the same condition. Semi-theoretical models were used for drying data fitting, and the diffusional model was used to describe the moisture transfer and calculate the effective diffusivity. Water activity, ascorbic acid, total carotenoids and colour analyses were performed. Results and conclusions. The combination of ethanol and ultrasound as a pretreatment reduced the drying time of pineapple. Higher effective moisture diffusivities were obtained when ethanol and ultrasound were applied before drying. The two-term exponential model presented the best fit for drying experimental data. The dried samples had a darker colour than the fresh sample. The pretreatment with ethanol resulted in increased retention of the studied bioactive components. The satisfactory results of this study represent an improvement in the drying process. Novelty and scientific contribution. Ultrasound and ethanol as a pretreatment to convective drying are promising. However, each food matrix has a typical structure and composition. Therefore, the application of the pretreatment in other products or using other conditions is still necessary to deeply understand and explain their effect on the process and the quality of the dried products.Pozadina istraživanja. Sušenje predstavlja održivi postupak konzerviranja hrane, a za sušenje biljnog materijala najčešće se koristi konvekcijska sušara. Međutim, ovaj postupak troši veliku količinu energije i može dovesti do negativnih promjena sastava hranjivih sastojaka i drugih parametara kakvoće hrane. Postupci prethodne obrade mogu umanjiti negativne učinke sušenja. Svrha je ovoga rada bila procijeniti postupak obrade ananasa etanolom i ultrazvukom prije konvekcijskog sušenja, te utvrditi učinak tih postupaka na boju, aktivitet vode, te udjele ukupnih karotenoida i askorbinske kiseline u dobivenom proizvodu. Eksperimentalni pristup. U postupku prethodne obrade uzorci voća uronjeni su u otopinu etanola različitih volumnih udjela tijekom 10 min, s primjenom ultrazvuka (25 kHz) ili bez njega, te su zatim sušeni pri temperaturi od 60 ºC. Kontrolna je skupina (bez prethodne obrade) sušena pri istim uvjetima. Dobiveni su rezultati prilagođeni korištenjem teorijskih kinetičkih modela, a pomoću difuzijskog modela opisan je prijenos vlage te izračunata efektivna difuzivnost vode. Ispitani su sljedeći parametri: aktivitet vode, udjeli askorbinske kiseline i ukupnih karotenoida, te boja dobivenog proizvoda. Rezultati i zaključci. Kombinacijom obrade etanolom i ultrazvuka smanjilo se trajanje sušenja ananasa. Veća je efektivna difuzivnost vlage postignuta primjenom etanola i ultrazvuka prije sušenja. Dvočlani eksponencijalni model najbolje je opisao eksperimentalno dobivene podatke. Sušeni su uzorci imali tamniju boju od svježih uzoraka. Prethodnom obradom etanolom zadržala se veća količina bioaktivnih spojeva. Zadovoljavajući rezultati ovog istraživanja predstavljaju poboljšanje postupka sušenja. Novina i znanstveni doprinos. Obrada etanolom i ultrazvukom prije konvekcijskog sušenja daje obečavajuće rezultate. Međutim, svaki prehrambeni artikl ima svojstvenu strukturu i sastav. Stoga je neophodno produbiti razumijevanje učinaka prethodne obrade na sušenje i kakvoću sušenog proizvoda

Restructuring Passiflora cincinnata fruit pulp: influence of hydrocolloids

This study evaluated the effect of mixtures of alginate, low methoxy pectin and gelatin on characteristics of P. cincinnata fruit gels, containing pulp with high soluble solids content (50 °Brix). The results of a central composite design showed that the models obtained, except for water activity and pH, were predictive. Gelatin was an important factor affecting firmness and colour parameters since higher concentrations of this hydrocolloid, combined with alginate concentrations greater than 1.3% and pectin quantity up to 1.26%, could be used to obtain clear yellow products with firmness greater that 1.2 kg