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Tofu was elaborated using water-soluble extract of soybean grains from the cultivar BRS 267 with cardoon flower (C. Cardunculus L.), as coagulant as an alternative to the traditional coagulant magnesium chloride. The tofu were evaluated in relation to physical, chemical, microbiological and sensory properties during 14 days. Was obsersed for the tofu coagulated with cardoon flower that the moisture, pH, total mineral, protein, and syneresis decreased with the storage, while Kunitz Trypsin Inhibitor, ureatic activity and phytic acid did not change. It was also obtained a positive effect for color (L*, a*) parameters, phytic acid, yield, syneresis, and acceptance. The textural properties, showed a tendency to increase of hardness and stickiness, while springiness and cohesiveness decreased during storage. Structurally, presented irregular-shaped, small pores or cavities. The sensory analysis, showed has great acceptance and purchase intent. Then, the cardoon flower can be used as vegetal coagulant improving the quality properties of tofu, in relation to magnesium chloride. El tofu se preparó utilizando extracto hidrosoluble de soja del cultivar BRS 267, utilizando la flor de cardo (C. Cardunculus L.), como coagulante alternativo al proceso tradicional con cloruro de magnesio. El tofu se evaluó por sus propiedades físicas, químicas, microbiológicas y sensoriales durante 14 días. Se observó para el tofu coagulado con la flor de cardo que la humedad, el pH, el mineral total, la proteína y la sinéresis disminuyeron con el almacenamiento, mientras que el inhibidor de tripsina de Kunitz, la actividad ureática y el ácido fítico no cambiaron. También se observó un efecto positivo para los parámetros de color (L *, a *), ácido fítico, rendimiento, sinéresis y aceptación. Las propiedades texturales mostraron una tendencia a aumentar la dureza y la gomina, mientras que la elasticidad y la cohesión disminuyeron durante el almacenamiento. Estructuralmente presentaba poros pequeños o cavidades irregulares. El análisis sensorial mostró una gran aceptación e intención de compra. Luego, la flor de cardo se puede utilizar como coagulante vegetal, mejorando las propiedades de calidad del tofu, en relación al cloruro de magnesio. O tofu foi elaborado usando extrato hidrossolúvel dos grãos de soja da cultivar BRS 267, utilizando a flor do cardo (C. Cardunculus L.), como coagulante alternativo ao processo tradicional com cloreto de magnésio. O tofu foi avaliado em relação as propriedades físicas, químicas, microbiológicas e sensoriais durante 14 dias. Foi observado para o tofu coagulado com a flor do cardo que a umidade, o pH, o mineral total, a proteína e a sinérese diminuíram com o armazenamento, enquanto o Inibidor de Tripsina de Kunitz, a atividade ureática e o ácido fítico não se alteraram. Foi também observado um efeito positivo para os parâmetros de cor (L *, a *), ácido fítico, rendimento, sinérese e aceitação. As propriedades texturais mostraram uma tendência de aumentar a dureza e a gomosidade, enquanto a elasticidade e a coesividade diminuíram durante o armazenamento. Estruturalmente, apresentou pequenos poros ou cavidades irregulares. A análise sensorial mostrou grande aceitação e intenção de compra. Então, a flor do cardo pode ser utilizada como coagulante vegetal melhorando as propriedades de qualidade do tofu, em relação ao cloreto de magnésio.

Given possible temperature variations in the cold chain during retail display of chilled food, this work evaluated the growth of Salmonella choleraesuis and Staphylococcus aureus inoculated in chicken breast fillet submitted to different temperature abuses. The bacterial growth was evaluated in Luria–Bertani broth and previously inoculated chicken breast fillet cooled for 12h and incubated at different temperatures (5, 20, and 25 °C) for 12 h and 5 ºC for 12 days. The maximum growth rate and maximum growth were determined. The microorganisms grew at all studied temperatures, with a significantly lower growth at 5 °C compared with 20 and 25 °C. S. choleraesuis showed higher growth than S. aureus in both culture medium and chicken breast, and major maximum growth in culture medium than chicken breast, at all studied temperatures. Salmonella sp. and S. aureus were not detected in the control treatment maintained at 5 °C, and the thermotolerant bacteria remained within the standards allowed by Brazilian legislation when stored for 12 days. However, temperature abuse resulted in the vulnerability and spoilage of chicken breast fillet quality. The effects of temperature abuse caused by negligence on the microbial growth (Ymax) and growth rate (µmax) in chicken breast fillet, under industrial conditions was demonstrated.

The packaging protects food from actions of external agents, from alterations and contaminations, in addition to adulteration. Edible films are structures produced from biopolymers, which can replace non-biodegradable packaging. These films have been formulated with naturally polymers of polysaccharides, lipids and proteins, isolated or combined with each other. Edible films produced with polysaccharides and proteins are transparent and flexible, although proteins films are less resistant. They act as a barrier, protecting food and increasing shelf life. Additionally, they can carry antimicrobial and antioxidant compounds, being called active films. The antioxidant power is proportional to the amount of the compound added. Natural extracts such as green tea, cloves, ginger and others can be incorporated into the films, wich could improving the mechanical properties of the films and the characteristics of the food. The use of active edible films has been evaluated in the meat industry as an alternative packaging. This review aims to address the use of edible films added with vegetable compounds, with antimicrobial and antioxidant activity, applied to meat products. El envase protege los alimentos de la acción de agentes externos, de cambios y contaminación, además de la adulteración. Las películas comestibles son estructuras producidas a partir de biopolímeros, que pueden reemplazar los envases no biodegradables. Estas películas se han formulado con polímeros naturales de polisacáridos, lípidos y proteínas, aislados o combinados entre sí. Las películas comestibles producidas con polisacáridos y proteínas son transparentes y flexibles, aunque las proteínas son menos resistentes. Actúan como una barrera, protegiendo los alimentos y aumentando la vida útil. Además, pueden transportar compuestos antimicrobianos y antioxidantes, que se denominan películas activas. El poder antioxidante es proporcional a la cantidad de compuesto agregado. Se pueden incorporar a las películas extractos naturales como té verde, clavo, jengibre y otros, lo que puede mejorar las propiedades mecánicas de las películas y las características del alimento. El uso de películas comestibles activas se ha evaluado en la industria cárnica como envasado alternativo. Esta revisión tiene como objetivo abordar el uso de películas comestibles añadidas con compuestos vegetales, con actividad antimicrobiana y antioxidante, aplicadas a productos cárnicos. A embalagem protege o alimento de ação de agentes externos, de alterações e contaminações, além de adulterações. Filmes comestíveis são estruturas produzidas a partir de biopolímeros, que podem substituir as embalagens não biodegradáveis. Esses filmes têm sido formulados com polímeros de ocorrência natural de polissacarídeos, lipídeos e proteínas, isolados ou combinados entre si. Filmes comestíveis produzidos com polissacarídeos e proteínas são transparentes e flexíveis, embora os proteicos sejam menos resistentes. Agem como barreira, protegendo o alimento e aumentando a vida de prateleira. Adicionalmente, podem carrear compostos antimicrobianos e antioxidantes, sendo denominados filmes ativos. O poder antioxidante é proporcional à quantidade do composto adicionado. Extratos naturais como chá verde, cravo, gengibre e outros podem ser incorporados aos filmes, que podem melhorar as propriedades mecânicas dos filmes e as características do alimento. A utilização de filmes comestíveis ativos têm sido avaliados na indústria de cárneos como embalagem alternativa. Esta revisão, tem por objetivo abordar a utilização de filmes comestíveis adicionados de compostos vegetais, com atividade antimicrobiana e antioxidante, aplicados em produtos cárneos.

SUMMARY The aim of this study is to elaborate and evaluate structural characteristics of soybean gelato by varying the content of soybean protein concentrate (2.95 to 17.05%) and vegetable fat (7.95 to 22.05%) using experimental design. The replacement of milk by hydrosoluble extract and soybean protein concentrate presented itself as an alternative to gelato production with unique characteristics, especially in terms of protein, solubility, viscosity, melting point, overrun and acceptability. The addition of up to 5% (m/V) protein concentrate, 14% (by volume) soybean hydrosoluble extract, and 15% (by mass) vegetable fat to gelato formulations resulted in better structural characteristics, with viscosity ranging from 0.45–0.70 Pa∙s at 10 °C, a non-Newtonian behaviour and protein stability (total protein content 8.44% and solubility 41%). Soybean gelato structural analysis using X-ray diffraction revealed 15° and 35° diffraction angles at 2Θ, characterizing the crystalline part of the product. The thermal analyses showed four bands of mass loss in the temperature range of 40–600 °C, characterizing loss of moisture, decomposition of the soy protein and the fat/emulsifier of the formulations. Thus, the soybean gelato is an innovative product, lactose and milk protein-free with outstanding characteristics for the general public, mainly, for the populations with intolerance to such components.

This paper aim to evaluate the ultrafiltration (UF) process for constituents recovery from whey. Sequences of factorial designs were performed by varying temperature (5 to 40°C) and pressure (1 to 3 bar), to maximize the proteins concentration using membrane of 100kDa in dead end system. Based on the best result new experiments were performed with membrane of 50kDa and 10kDa. With the membrane of 50 the protein retention was about 3 times higher than the membrane of 100kDa. The concentrated obtained by UF membrane of 10kDa, 10°C and 2 bar in laboratory scale showed a mean protein retention of 80 %, greater protein solubility, emulsion stability and the identification of β-lactoglobulins (18.3 kDa) and α-lactalbumin fractions (14.2kDa). Therefore, the use of membrane of 100 and 50kDa are became a industrially recommendable alternatives to concentration of whey proteins, and/or as a previous step to the fractionation of whey constituents using membrane ≤10kDa, aiming at future applications in different areas (food, pharmaceutical, chemical, etc.).

The aim of this work was to perform the screening of microorganisms, previously isolated from samples of agro-industrial waste and belonging to the culture collection of our laboratory, able to produce polygalacturonases (PG). A total of 107 microorganisms, 92 newly isolated and 15 pre-identified, were selected as potential producers of enzymes with PG activity. From these microorganisms, 20 strains were able to synthesize PG with activities above 3 U mL(-1). After the kinetic study, the enzyme activity was increased up to 13 times and the microorganism identified as Aspergillus niger ATCC 9642 and the newly isolated W23, W43, and D2 (Penicillium sp.) after 24 h of fermentation led to PG activities of 30, 41, 43, and 45 U mL(-1), respectively. The RAPD analysis demonstrated that the selected strains differs genetically, indicating that no duplication of strains among them in the experiments for polygalacturonases production was verified.