This study aimed to evaluate the influence of drying air temperature on drying kinetics and the physicochemical properties of dried bananas. Banana slices were dried at 40, 60, and 80°C. Drying was terminated when the samples had a moisture of 20%. Mathematical models were fitted to the moisture ratio. A generalized model of moisture was developed, to predict the moisture of samples as a function of drying time and temperature. The effective moisture diffusivity (Deff), activation energy and the drying rate (DR) were calculated. Electrical energy consumption was measured. The moisture, water activity, reducing and total sugar content, acidity, hardness, and color of the dried bananas were evaluated. The moisture decreased during drying, obtaining a mean value of 20.132%. All mathematical models fitted well to the MR data, with a determination coefficient greater than 0.95. The Midilli model was that which best fitted. The higher temperature resulted in higher Deff (3.538 × 10−9 m2 s−1) and DR, less drying time (120 min) and electrical energy consumption (4.319 kWh), higher reducing sugar content (47.51%) and hardness (28.187 N), lower acidity (1.038%), more yellow tonality (78.04°), and higher chromaticity (18.49) of the dried bananas. The optimum temperature for drying bananas was 80°C. Practical Applications Banana is a fruit widely consumed in the world. However, it is very perishable, causing great waste and financial loss. Convective drying is a simple and low‐cost method, widely used in fruit processing to produce new products and extend the shelf life of food. The dried banana is a product of good sensory acceptance and therefore drying is a good alternative for processing the banana pulp. The temperature of the drying air is one of the principal parameters of this process since it influences the drying kinetics and the physicochemical properties of the dry product. Therefore, it is important to study different drying air temperatures to determine the best drying condition for dried banana production, to optimize the dried banana process and properties.

Neste trabalho objetivou-se estabelecer a proporção de banana, a composição da solução extratora, bem como o tempo de extração para produzir licor com qualidade. Efetuou-se experimento fatorial com três quantidades de polpa de banana (500, 800 e 1100 g de banana para produção de 4 L de licor) e dois teores alcoólicos da solução extratora (70 e 95°GL). O processo de extração foi estudado durante 21 dias em que se analisaram as coordenadas de cor, pH, teor de sólidos solúveis e densidade a 20°C do extrato. O licor jovem foi caracterizado e submetido à análise sensorial após 45 dias de envelhecimento. O tempo de 16 dias mostrou-se suficiente para finalizar a etapa de extração, evidenciando que o tempo de infusão deve ser de 15 a 16 dias. A solução extratora com teor alcoólico de 95°GL apresentou melhores resultados, principalmente no que se refere à cor final do produto e facilidade na filtração. Como não houve diferença significativa entre as quantidades de polpa de banana optouse pela menor proporção em razão de fatores econômicos. Portanto, a utilização de 500 g de polpa de banana é suficiente para produzir 4 L de licor.

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Este é um artigo publicado em acesso aberto (Open Access) sob a licença Creative Commons Attribution, que permite uso, distribuição e reprodução em qualquer meio, sem restrições desde que o trabalho original seja corretamente citado. Cinética de secagem de acerola em leito de espuma e ajuste de modelos matemáticos Foam-mat drying kinetics for acerola and adjustment of the mathematical models ResumoA acerola (Malpighia emarginata DC) é uma fruta rica em nutrientes, principalmente vitamina C. No entanto, a perecibilidade do fruto in natura é alta. Desta forma, o processamento do fruto torna-se indispensável. Diante disto, o presente trabalho teve o objetivo de estudar a etapa de secagem da polpa de acerola em leito de espuma, além de avaliar o efeito da temperatura sobre a cinética de secagem da polpa de acerola e ajustar modelos matemáticos para descrever o processo. O experimento foi conduzido em três repetições. A espuma foi elaborada com 250 mL da polpa de acerola adicionada de 4% do agente espumante, sendo, então, espalhada uniformemente em bandejas de inox. AbstractAcerola (Malpighia emarginata DC) is a fruit rich in nutrients, especially vitamin C, but the in natura fruit is highly perishable and hence processing of the acerola pulp becomes indispensable. The aim of this paper was to study the foam mat drying process of acerola pulp to evaluate the effect of temperature on the drying kinetics of the pulp and fit mathematical models in order to describe the operation. The experiment was carried out with three repetitions. The foam was prepared with 250 mL of the pulp plus 4% of foaming agent and spread evenly in stainless steel trays. The selected drying air temperatures were 50 °C, 55 °C, 60 °C, 65 °C and 70 °C. The moisture ratios were then calculated and the Page, Henderson and Pabis and Lewis mathematical models fitted for each temperature. The Page model showed the highest determination coefficient (> 0.99) and lowest standard error for the regression at all temperatures (<0.03). The proposed generalized model presented a determination coefficient of 0.9933. The Page model and the generalized model were adequate to describe the drying process of the acerola pulp. The moisture contents of the dehydrated products were in accordance with the values established by Brazilian law. Keywords

This study aimed to evaluate the changes throughout storage of pasta formulations enriched with basil, beet, cheese, chocolate, coffee, dried tomato, ginger, pepper, rosemary, socol, spinach, and wine in metallic and transparent packages. Pasta color, moisture content, water activity (aw), pH, total titratable acidity, cooking time, water absorption, and cooking loss were evaluated for 120 days. The packages used were efficient throughout storage in preserving moisture, aw, pH, total titratable acidity, cooking time, and water absorption for all formulations. Cooking loss and kinetics of the total color difference (ΔE) of some pasta were significantly (p < .05) affected. Beet pasta was the only one that showed a significant difference in cooking loss (p < .05) and ΔE was not influenced by packaging and storage time. Spinach pasta presented the largest ΔE between the two packaging types after 120 days. The metallic packaging was better at preservation of the pasta color throughout storage. Practical applications Adding ingredients in pasta formulations is a good alternative for the manufacture of products with attractive consumer features. Storage time and packaging are factors that can influence the quality of pasta, generating characteristics that may affect the product. Therefore, the study of these factors for different types of pasta provides relevant information for the food industries, since it is possible to identify the storage conditions that promote the lower change in quality. The results indicated that storage time and packaging are factors that influenced mainly the preservation of color characteristics of pasta containing added nontraditional ingredients. Metallic packaging can be considered an efficient alternative to reduce color change throughout the storage.