Impact of encapsulated orange essential oil with ß-cyclodextrin on technological, digestibility, sensory properties of wheat cakes as well as Aspergillus flavus spoilage.

BACKGROUND: The majority of studies with essential oils in foods focus mainly on improving the shelf life of products; however, the present study goes further and demonstrates not only the effect of essential oil on conservation properties, but also the effect of free and encapsulated orange essential oil (OEO) on the technological, sensorial and digestibility properties of bakery products. RESULTS: OEO was encapsulated into ß-cyclodextrin (ß-CD) by inclusion complex formation (ß-CD/OEO 97.4% of encapsulation efficiency). OEO demonstrated in vitro antifungal activity against Aspergillus flavus (inhibition zone of 11.33 mm on mycelial growth). In situ antifungal activity against A. flavus confirmed that free OEO can effectively delay the fungal growth, unlike encapsulated OEO. Regarding texture profile and starch digestibility: cake with ß-CD/OEO showed lower hardness (31.64 N) and lower starch digestibility (69.10%) than cake with free OEO (44.30 N; 82.10%, respectively) and the addition of OEO (both free and encapsulated) decreased the adhesiveness of the cakes. Cake with free OEO showed a higher intensity of orange aroma, being preferred by 60% of panelists, whereas cake with ß-CD/OEO presented a very slight orange taste and aroma. CONCLUSION: The encapsulation of OEO into ß-CD improved the crumb texture of cakes and promoted a lower starch digestibility in the cakes. On the other hand, the encapsulation process was not effective under the conditions tested (OEO concentration and baking temperatures), compromising the action of the OEO as a natural flavoring and preservative agent. © 2021 Society of Chemical Industry.

Peptides from Chia Present Antibacterial Activity and Inhibit Cholesterol Synthesis.

In previous studies, it has not been reported that protein isolated from chia interferes favorably with antibacterial activity, and reduces cholesterol synthesis. The objective of this study was to determine whether commonly used commercial microbial proteases can be utilized to generate chia protein-based antibacterial and hypocholesterolemic hydrolysates/peptides, considering the effects of protein extraction method. Alcalase, Flavourzyme and sequential Alcalase-Flavourzyme were used to produce hydrolysates from chia protein (CF), protein-rich fraction (PRF) and chia protein concentrates (CPC1 and CPC2). These hydrolysates were evaluated for their antimicrobial activity against Gram-positive (G+) and Gram-negative (G-) microorganisms. The protein hydrolysates were purified by ultrafiltration through a membrane with 3 kDa nominal molecular weight, for evaluation of hypocholesterolemic activity. An inhibition zone was observed when the hydrolysate was tested against S. aureus, and minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were obtained. Peptides from chia protein with molecular mass lower than 3 kDa reduced up to 80.7% of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) enzymatic reaction velocity. It was also observed that, independent of the method used to obtain chia proteins, the fractions showed relevant bioactivity. Moreover, the intensity of the bioactivity varied with the method for obtaining the protein and with the enzyme used in the hydrolysis process. This is the first report to demonstrate that chia peptides are able to inhibit cholesterol homeostasis.

Valorisation of olive pomace: phenolic prospecting and biological potential.

Phenolic compounds were extracted from biphasic olive pomace and their biological potential was characterised. Two different extracts were prepared, E1 (40% methanol) and E2 (80% methanol), both subjected to agitation (180 min) and 70 °C. LC-ESI-qTOF-MS was used for individual quantification of the extracted phenolic compounds. The antioxidant activity was determined using different methods, including nitric oxide, DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydroxyl radical. The enzymes α-amylase and α-glucosidase were used to evaluate the antihyperglycemic potential and sulforhodamine B and MTT (tetrazolium salt) for antitumor activity. To evaluate the antimicrobial activity, minimum inhibitory concentration and minimum bactericidal concentration of the extracts, the disc diffusion technique was used. Among the phenolic compounds present, tyrosol was highlighted in both extracts, as well as the anti-hyperglycemic effects, antitumor action and antioxidant activity. The antimicrobial activity found in the extracts was considered moderate to weak.

Starch extraction from avocado by-product and its use for encapsulation of ginger essential oil by electrospinning.

Starches from alternative sources, such as avocado seed, have potential for application in the encapsulation of essential oils. This study aimed to extract starch from avocado seeds and its use as wall material to encapsulate ginger essential oil (GEO), at different concentrations. The fibers were produced by electrospinning and evaluated by morphology, size, infrared spectra, thermogravimetric properties, contact angle, loading capacity, and antibacterial activity. The major compounds in GEO were α-zingiberene, ß-sesquiphellandrene, α-farnesene, and α-curcumene. The starch-GEO fibers presented a higher diameter (∼553 nm) than those without GEO (345 nm). Encapsulation of GEO in starch fibers increased their thermal degradation temperatures from 165.8 °C (free GEO) to 257.6 °C (40 % GEO fibers). The starch-GEO fibers presented characteristic bands of their constituents by infrared spectra. Loading capacity ranged from 44 to 54 %. The fibers showed hydrophilic character, with a contact angle of <90°. Free GEO and the fibers with 50 % of GEO displayed antibacterial activity against Escherichia coli, proving the bioactivity of the starch-GEO fibers and its possible applicability for food packaging. Avocado seed starch showed to be a great wall material for GEO encapsulation.

Red onion skin extract rich in flavonoids encapsulated in ultrafine fibers of sweet potato starch by electrospinning.

Electrospinning encapsulation is a highly viable method to protect bioactive compounds and prevent their degradation. Hence, this study produced ultrafine fibers based on yellow and white sweet potato starches and a red onion skin extract (ROSE; 0, 3, 6, and 9 %, w/w) using electrospinning. The fibers were evaluated for morphology, thermogravimetric properties, antioxidant, in vitro release simulation, thermal resistance (100 and 180 °C), and wettability. The fibers with ROSE presented 251-611 nm diameters, 67-78 % loading capacity, and 51.6-95.4 and 13.4-99.4 % thermal resistance (100 and 180 °C, respectively); apigenin presented the highest thermal protection. The phenolic compounds showed low release using 10 % ethanol and greater release with 50 % ethanol. The fibers with 9 % ROSE showed 2,2'-azino-bis(3-ethylbenzothiazoline) 6-sulfonic acid radical inhibition above 92 %. The ultrafine fibers and the unencapsulated ROSE showed inhibitory action against Escherichia coli and Staphylococcus aureus; only unencapsulated ROSE showed bactericidal activity.

Oleogels based on germinated and non-germinated wheat starches and orange essential oil: Application as a hydrogenated vegetable fat replacement in bread.

This study aimed to produce oleogels based on non-germinated and germinated wheat starches with orange essential oil, apply them to replace hydrogenated vegetable fat in bread, and assess the antifungal action. The oleogels were prepared using sunflower oil, wheat starches, beeswax, water, and orange essential oil (OEO). They were evaluated to determine the volatile compounds, oil binding capacity, texture profile, storage stability for 20 days, thermogravimetric analysis, and functional groups. The breads were evaluated by their moisture content, specific volume, texture profile, volatile compounds, and microbiological contamination during 15 days of storage. The oleogels showed high storage stability, were fully intact after 20 days of storage, and had a high oil binding capacity (∼100 %). The oleogels with OEO presented increased adhesiveness and reduced hardness compared to the ones without essential oil. The oleogels with OEO based on germinated wheat starch released a high amount of volatile compounds. Substituting saturated vegetable fat with oleogels in bread formulation resulted in decreased hardness and maintained specific volume. Furthermore, incorporating OEO oleogels in the bread led to reduced growth of total mesophiles and fungi.

Detection of Salmonella by the 3M Molecular Detection Assays: MDS® Method.

Developed by 3M Company, 3M ™ Molecular Detection Assays-3M MDS-enable detection of Salmonella from advanced isothermal DNA amplification and bioluminescence detection technology. It can be used for a wide variety of products, including poultry, eggs, pet foods, and environmental samples, and results are obtained within about 24 h. In this chapter, all steps of the 3M MDS™ method for detection of Salmonella are described and detailed.

Suitability of starch/carvacrol nanofibers as biopreservatives for minimizing the fungal spoilage of bread.

The objective of this study was to evaluate the in vitro susceptibility of fungi to starch/carvacrol nanofibers produced by electrospinning. The nanofibers were incorporated into bread dough or used in the development of active packages to minimize bread spoilage. In agar diffusion and micro-atmosphere assays, the nanofibers with 30 % or 40 % carvacrol presented inhibition zones with low growth and were effective inhibiting both the fungi evaluated in this work. The MICs for nanofibers with 30 % carvacrol were 0.098 and 9.8 mg/mL against Penicillium sp. and Aspergillus flavus, respectively; for the 40 % nanofibers, the MIC was 19.6 mg/mL against Aspergillus flavus. As for MFC, only the 30 % nanofibers exerted fungicidal effect. The treatments administered directly to the bread dough had low colony-forming unit. For bioactive packages, nonwovens with 30 % carvacrol were effective in preventing bread spoilage. Thus, nanofibers are a good alternative to chemical additives or bioactive packages in food industry.

Pinhão coat extract encapsulated in starch ultrafine fibers: Thermal, antioxidant, and antimicrobial properties and in vitro biological digestion.

This study aimed to produce soluble potato starch ultrafine fibers for the encapsulation of pinhão coat extract (PCE), evaluating their relative crystallinity (RC), thermal stability, antioxidant activity, antimicrobial activity against Escherichia coli and Staphylococcus aureus, as well as in vitro biological digestion. In the simulation of in vitro biological digestion, the phenolic compounds release profile was also evaluated. The ultrafine fibers were produced by electrospinning, based on a polymeric solution composed of soluble potato starch (50% w/v) and formic acid. Then, PCE was incorporated at various concentrations (0.5%, 1.0%, and 1.5%, w/w, dry basis). The endothermic event of free PCE was not observed in the ultrafine fibers, which suggests its encapsulation. The RC decreased according to the increase in PCE concentration in the ultrafine fibers. The PCE resisted thermal treatments when encapsulated into the ultrafine fibers (100 and 180°C), and the ultrafine fibers with 1% PCE presented the highest amount of preserved phenolic compounds. Regarding antioxidant activity, the free PCE presented 85% of DPPH inhibition and the ultrafine fibers had 18% inhibition, not differing among the PCE concentrations (p < 0.05). The free PCE and the ultrafine fibers with 0.5% PCE showed inhibitory effect against S. aureus and the ones with 1.5% PCE showed controlled release of phenolic compounds during the simulation of in vitro digestion. Starch ultrafine fibers showed potential to be applied in food industries due to their capacity of protecting phenolic compounds when submitted to high temperatures or gastrointestinal conditions. Nevertheless, their application depends on the end use of the product. PRACTICAL APPLICATION: The encapsulation of pinhão coat extract (PCE) in ultrafine starch fibers promotes greater preservation of phenolic compounds. Thus, it can be incorporated into different foods that are produced using the ultra-high temperature (UHT) process-at 135-145°C for 5 to 10 s, or some other equivalent time/temperature combination. Another possibility is the incorporation of ultrafine fibers in active packaging: compounds can migrate to food, improving sensory characteristics, increasing shelf life, preventing chemical and microbiological deterioration, and ensuring food safety.

Antimicrobial potential of spray drying encapsulated thyme (Thymus vulgaris) essential oil on the conservation of hamburger-like meat products.

Synthetic preservatives can have harmful effects on the body, so plant essential oils appear to be an attractive natural alternative. However, the use of essential oils is limited due to the low stability and possible negative effects on the sensory properties of food. Oil encapsulation was suggested as a way to overcome these drawbacks. The objective of this study was to encapsulate thyme essential oil and to evaluate its antioxidant and antimicrobial potential in vitro and in situ in of hamburger-like meat products. The casein-maltodextrin capsules produced by spray-drying were assessed for encapsulation efficiency, thermal stability, chemical compounds and morphology. Antioxidant activity was evaluated by DPPH, hydroxyl and nitric oxide methods, while antimicrobial activity was evaluated in vitro against four bacteria and in situ in hamburger-like products. The capsule showed high encapsulation efficiency and thermal stability, and spherical and irregular morphology. The casein-maltodextrin encapsulated essential oil showed antioxidant and antimicrobial activity against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella Typhimurium tested in vitro and against thermotolerants coliforms and Escherichia coli in situ, showing potential for application as a natural preservative in food.

Antimicrobial and antioxidant activity of unencapsulated and encapsulated clove (Syzygium aromaticum, L.) essential oil.

Clove (Syzygium aromaticum, L.) essential oil is known for its antimicrobial activity against several pathogenic bacteria. Encapsulation of clove oil was proposed as a mean to disguise its strong odor that limits its uses in food industry. Thus, the aim of this study was extraction, encapsulation and assessment of the antimicrobial and antioxidant potential of clove essential oil. The essential oil showed high DPPH scavenging capacity and low hydroxyl radical inhibition. Clove essential oil showed in vitro inhibitory and bactericidal effect against S. aureus, E. coli, L. monocytogenes and S. Typhimurium. In addition, in situ antimicrobial activity of clove oil against S. aureus was superior to nitrite. The essential oil particles encapsulated with sodium alginate and emulsifiers, showed high encapsulation efficiency, low antioxidant activity and strong antimicrobial inhibition. Similar bacterial growth was observed in meat-like products after addition of either particles or nitrite.

Evaluating pinhão conservation by using ionizing radiation and refrigeration

Pinhão is highly perishable due to its high water activity, being easily affected by fungi during storage and also susceptible to infestation by larvae. This seed is usually marketed in the pinhão cones itself, or bulk threshed, and packed in plastic bags, chilled or ground frozen. Pinhão conservation and industrialization techniques should be developed to promote its commercialization and consumption at other times of the year, besides the seasonal period, encouraging its sustainable production, extraction and commercialization, considering its essentially extractive character. The objective of this study was to evaluate the conservation of pinhão by the use of gamma radiation and refrigeration. The pinhões were irradiated with a cobalt­60 source at a dose rate of 1 kGy. A non-irradiated sample was used as a control. The pinhões were packed in high-density polyethylene bags and stored at ambient temperature and refrigerated at 4 ºC, during 90 days. Pinhões were evaluated for weight loss, acidity, reducing sugars, vitamin C, firmness, color, total phenolic compounds, antioxidant activity and microbiological analyzes. The isolated use of gamma radiation was not effective for the maintenance of the evaluated parameters. However, when used in conjunction with refrigerated storage, it reduced the growth of aerobic fungi, as well as mesophilic and psychrotrophic microorganisms. The isolated use of refrigeration showed a reduction in weight loss, reducing sugars and an increase in vitamin C content and antioxidant activity. Thus, to increase the benefits, we suggest evaluating higher doses of radiation as a function of the thick pinhão shell.

Formação de biofilmes e resistência a antimicrobianos de isolados de Salmonella spp / Biofilm formation and antimicrobial resistance of Salmonella spp. isolates

O presente estudo avaliou a presença de Salmonella spp. em 89 amostras de produtos cárneos comercializados na região sul do Rio Grande do Sul e, a partir dos isolados obtidos, foi verificada a capacidade de resistência a agentes antimicrobianos e de formação de biofilme em superfícies de poliestireno. Foi constatada a presença de Salmonella spp. em 19,1% das amostras avaliadas e, dos isolados obtidos, 40% mostraram resistência a pelo menos um dos agentes antimicrobianos testados e 33,3% manifestaram-se multirresistentes. Apenas o antimicrobiano amicacina (30 µg) foi eficaz na inibição de todos os isolados testados. Nenhum isolado mostrou-se capaz de formar biofilmes em superfícies de poliestireno.

The objective of the study was to evaluate the presence of Salmonella spp. in 89 samples of meat products marketed in southern Rio Grande do Sul and from isolates obtained was verified the ability of resistance to antimicrobials and biofilm formation on polystyrene surfaces. The presence of Salmonella spp. was found in 19.1% of the samples. Of the isolates obtained, 40% showed resistance to at least one of the tested antimicrobials and 33.3% expressed multiresistant. Only the antimicrobial amikacin (30 µg) was effective in inhibiting all isolates tested. No isolate was able to form biofilms on polystyrene surfaces.

Formação de biofilmes e resistência a antimicrobianos de isolados de Salmonella spp. / Biofilm formation and antimicrobial resistance of Salmonella spp. isolates

O presente estudo avaliou a presença de Salmonella spp. em 89 amostras de produtos cárneos comercializados na região sul do Rio Grande do Sul e, a partir dos isolados obtidos, foi verificada a capacidade de resistência a agentes antimicrobianos e de formação de biofilme em superfícies de poliestireno. Foi constatada a presença de Salmonella spp. em 19,1% das amostras avaliadas e, dos isolados obtidos, 40% mostraram resistência a pelo menos um dos agentes antimicrobianos testados e 33,3% manifestaram-se multirresistentes. Apenas o antimicrobiano amicacina (30 µg) foi eficaz na inibição de todos os isolados testados. Nenhum isolado mostrou-se capaz de formar biofilmes em superfícies de poliestireno.(AU)

The objective of the study was to evaluate the presence of Salmonella spp. in 89 samples of meat products marketed in southern Rio Grande do Sul and from isolates obtained was verified the ability of resistance to antimicrobials and biofilm formation on polystyrene surfaces. The presence of Salmonella spp. was found in 19.1% of the samples. Of the isolates obtained, 40% showed resistance to at least one of the tested antimicrobials and 33.3% expressed multiresistant. Only the antimicrobial amikacin (30 µg) was effective in inhibiting all isolates tested. No isolate was able to form biofilms on polystyrene surfaces.(AU)

Chemical characterization, antimicrobial and antioxidant activity of sugar-apple (Annona squamosa L. ) pulp extract / Caracterización química, actividad antimicrobiana y antioxidante del extracto de pulpa de manzana de azúcar (Annona squamosa L. )

Synthetic preservatives are widely present in processed foods, but most of them have carcinogenic potential, requiring the development of new natural alternatives such as fruit extracts, for microbial control. The objective of the study was to evaluate the chemical characterization, antioxidant, and antimicrobial activity of the sugar apple pulp (Annona squamosa L.). Physicochemical characteristics were evaluated, an extract was prepared, and its antioxidant activity by DPPH method and antimicrobial by disk diffusion. Minimal inhibitory concentration and minimum bactericidal concentration against strains of Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus were evaluated. The physicochemical analysis revealed that sugar apple pulp had 75.0% moisture, 3.0% ash, 4.0% protein, 0.2% lipids, 3.3% fibers, and 14.5% carbohydrates. The antioxidant activity of the extract by the DPPH method was 20.6%. The pulp extract from the sugar apple had inhibition zone for Staphylococcus aureus, satisfactory inhibitory effect against Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium, but did not present a bactericidal effect. Sugar apple pulp presents adequate levels of nutrients and potential for food application due to its microbiological activity and antioxidant properties.

Los conservantes sintéticos están ampliamente presentes en los alimentos procesados, pero la mayoría tienen potencial carcinogénico, lo que requiere el desarrollo de nuevas alternativas naturales para el control microbiano, como los extractos de frutas. El objetivo del estudio fue evaluar la caracterización química, la actividad antioxidante y antimicrobiana de la pulpa de manzana de azúcar (Annona squamosa L.). Se evaluaron las características fisicoquímicas, y se evaluó su actividad antioxidante mediante el método DPPH y antimicrobiano por difusión en disco, concentración inhibitoria mínima y concentración bactericida mínima contra cepas de Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes y Staphylococcus aureus. El análisis fisicoquímico reveló que la pulpa de manzana de azúcar tiene 75.0% de humedad, 3.0% de cenizas, 4.0% de proteínas, 0.2% de lípidos, 3.3% de fibras y 14.5% de carbohidratos. La actividad antioxidante del extracto por el método DPPH fue del 20.6%. El extracto de pulpa de la manzana de azúcar tenía zona de inhibición para Staphylococcus aureus, efecto inhibidor satisfactorio contra Staphylococcus aureus, Escherichia coli, Listeria monocytogenes y Salmonella Typhimurium, pero no presenta efecto bactericida. La pulpa de manzana de azúcar presenta niveles adecuados de nutrientes y potencial para la aplicación de alimentos debido a su actividad microbiológica y propiedades antioxidantes.

Storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics / Conservação de pinhão minimamente processado pelo uso de revestimentos comestíveis com características antimicrobianas

The pinhão shows high nutritional value; however, its consumption is still low owing to the long cooking time required because it is hard to peel, and it is susceptible to sprouting, larval infestation, and fungal contamination. Thus, this study aimed to evaluate the storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics. The pinhões were subjected to minimal processing with the following treatments: Treatment A - control; Treatment B - chitosan; Treatment C - xanthan gum and clove essential oil. After drying, they were packed in polyethylene terephthalate and stored at 4 °C for nine days. The pinhões were analyzed for mass loss, total acidity, reducing sugars, vitamin C, color, firmness, respiratory rate, sensory characteristics, and microbial growth. In general, no differences were observed in mass loss, reducing sugars, and oxygen concentrations of the pinhões after any treatment. In addition, we observed a reduction in acidity and carbon dioxide concentrations, maintenance of color parameters, and the absence of growth of thermotolerant coliforms and coagulase positive Staphylococcus. Although the minimal processing did not increase the respiratory rate of pinhões, it did not stop the process of seed maturation. Of the coatings evaluated, chitosan coating of the pinhões was associated with a higher content of vitamin C as well as a lower number of psychrotrophic microorganisms. The coatings did not influence the taste and aroma of the minimally processed pinhões.(AU)

O pinhão apresenta alto valor nutricional, entretanto seu consumo ainda é pouco expressivo devido ao longo tempo de cocção, por apresentar um difícil descasque, ser susceptível ao processo de brotamento, infestação por larvas e deterioração fúngica. Assim, o presente trabalho teve por objetivo avaliar a conservação de pinhões minimamente processados por meio de revestimentos comestíveis com características antimicrobianas. Os pinhões foram submetidos ao processamento mínimo e após aos diferentes tratamentos: Tratamento A - controle; Tratamento B - quitosana; Tratamento C - xantanae óleo essencial de cravo-da-índia. Após, foram secos sob ventilação forçada, acondicionados em embalagem de Polietileno Tereftalato (PET) e armazenados a 4 ºC, durante 9 dias. Foram realizadas avaliações de perda de massa, acidez total titulável, açúcares redutores, vitamina C, firmeza, cor, taxa respiratória, análise sensorial e microbiológica. De uma forma geral, independente do tratamento, pôde se observar comportamento semelhante nas características dos pinhões, em relação ao aumento da perda de massa, dos açúcares redutores, da concentração de oxigênio e da deterioração fisiológica. Além disso, foi observada a redução da acidez e da concentração de dióxido de carbono, bem como a manutenção dos parâmetros de cor e a ausência de crescimento de coliformes termotolerantes e Staphylococcus coagulase positiva. O processamento mínimo não elevou a taxa respiratória dos pinhões, porém não freou o processo de maturação das sementes. Dos revestimentos avaliados, a quitosana possibilitou a obtenção de pinhões com maior teor de vitamina C e contagem de microrganismos psicrotróficos. Os revestimentos não influenciaram no sabor e aroma dos pinhões minimamente processados.(AU)

Storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics / Conservação de pinhão minimamente processado pelo uso de revestimentos comestíveis com características antimicrobianas

The pinhão shows high nutritional value; however, its consumption is still low owing to the long cooking time required because it is hard to peel, and it is susceptible to sprouting, larval infestation, and fungal contamination. Thus, this study aimed to evaluate the storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics. The pinhões were subjected to minimal processing with the following treatments: Treatment A - control; Treatment B - chitosan; Treatment C - xanthan gum and clove essential oil. After drying, they were packed in polyethylene terephthalate and stored at 4 °C for nine days. The pinhões were analyzed for mass loss, total acidity, reducing sugars, vitamin C, color, firmness, respiratory rate, sensory characteristics, and microbial growth. In general, no differences were observed in mass loss, reducing sugars, and oxygen concentrations of the pinhões after any treatment. In addition, we observed a reduction in acidity and carbon dioxide concentrations, maintenance of color parameters, and the absence of growth of thermotolerant coliforms and coagulase positive Staphylococcus. Although the minimal processing did not increase the respiratory rate of pinhões, it did not stop the process of seed maturation. Of the coatings evaluated, chitosan coating of the pinhões was associated with a higher content of vitamin C as well as a lower number of psychrotrophic microorganisms. The coatings did not influence the taste and aroma of the minimally processed pinhões.

O pinhão apresenta alto valor nutricional, entretanto seu consumo ainda é pouco expressivo devido ao longo tempo de cocção, por apresentar um difícil descasque, ser susceptível ao processo de brotamento, infestação por larvas e deterioração fúngica. Assim, o presente trabalho teve por objetivo avaliar a conservação de pinhões minimamente processados por meio de revestimentos comestíveis com características antimicrobianas. Os pinhões foram submetidos ao processamento mínimo e após aos diferentes tratamentos: Tratamento A - controle; Tratamento B - quitosana; Tratamento C - xantanae óleo essencial de cravo-da-índia. Após, foram secos sob ventilação forçada, acondicionados em embalagem de Polietileno Tereftalato (PET) e armazenados a 4 ºC, durante 9 dias. Foram realizadas avaliações de perda de massa, acidez total titulável, açúcares redutores, vitamina C, firmeza, cor, taxa respiratória, análise sensorial e microbiológica. De uma forma geral, independente do tratamento, pôde se observar comportamento semelhante nas características dos pinhões, em relação ao aumento da perda de massa, dos açúcares redutores, da concentração de oxigênio e da deterioração fisiológica. Além disso, foi observada a redução da acidez e da concentração de dióxido de carbono, bem como a manutenção dos parâmetros de cor e a ausência de crescimento de coliformes termotolerantes e Staphylococcus coagulase positiva. O processamento mínimo não elevou a taxa respiratória dos pinhões, porém não freou o processo de maturação das sementes. Dos revestimentos avaliados, a quitosana possibilitou a obtenção de pinhões com maior teor de vitamina C e contagem de microrganismos psicrotróficos. Os revestimentos não influenciaram no sabor e aroma dos pinhões minimamente processados.

Formação de biofilme por Staphylococcus aureus isolados de queijo mussarela elaborado com leite de búfala e seu efeito sobre a sensibilidade a sanitizantes / Biofilm formation by coagulase-positive staphylococcus aureus isolated from mozzarella cheese elaborated with buffalo milk and its effect on sensitivity to sanitizers

Background: The buffalo milk mozzarella cheese is a new product in the market, with high consumer acceptance and excellent prospects for trade. The cheese is rich in nutrients, which favors the proliferation of microorganisms that can cause food-borne diseases in the consumer. Staphylococcus aureus can cause gastro-enteritis in humans by the production of enterotoxins in food. One problem that may hinder the elimination of undesirable microorganisms in the food industry is the formation of biofilms. The objective of this study was to determine the effect of biofilm formation by Staphylococcus aureus isolated from buffalo mozzarella cheese on sensitivity to sanitizers.Materials, Methods & Results: Fifty samples of buffalo mozzarella cheese were analyzed to investigate the presence of S. aureus. The isolates were obtained through microbiological analysis and identified by PCR. The similarity of the strains was compared through rep-PCR. The distinct strains were tested for biofilm formation in microtiter plates. Soy Tripticase Broth (TSB) was placed in each well of the microtiter plate and overnight cultures of each strain was added. Wells without bacterial culture were used as controls. A villous cap was then placed on the plate and incubated for 48 h at 37°C. During incubation, the biofilms formed on the surface of the villi of the caps. For quantification of biofilm formation, material that remained attached to the cap was stained with crystal violet, the stained biofilm was extracted and the OD570 of each well was measured. Each strain was classified as non-biofilm forming, weak forming, moderately formed or formative strong. Strong forming and non-biofilm forming strains were tested on high density polyethylene, stainless steel and glass surfaces. Plates of 4 cm² of the different materials were placed in TSB where the culture of each isolate was inoculated separately.[...](AU)

Formação de biofilme por Staphylococcus aureus isolados de queijo mussarela elaborado com leite de búfala e seu efeito sobre a sensibilidade a sanitizantes / Biofilm formation by coagulase-positive staphylococcus aureus isolated from mozzarella cheese elaborated with buffalo milk and its effect on sensitivity to sanitizers

Background: The buffalo milk mozzarella cheese is a new product in the market, with high consumer acceptance and excellent prospects for trade. The cheese is rich in nutrients, which favors the proliferation of microorganisms that can cause food-borne diseases in the consumer. Staphylococcus aureus can cause gastro-enteritis in humans by the production of enterotoxins in food. One problem that may hinder the elimination of undesirable microorganisms in the food industry is the formation of biofilms. The objective of this study was to determine the effect of biofilm formation by Staphylococcus aureus isolated from buffalo mozzarella cheese on sensitivity to sanitizers.Materials, Methods & Results: Fifty samples of buffalo mozzarella cheese were analyzed to investigate the presence of S. aureus. The isolates were obtained through microbiological analysis and identified by PCR. The similarity of the strains was compared through rep-PCR. The distinct strains were tested for biofilm formation in microtiter plates. Soy Tripticase Broth (TSB) was placed in each well of the microtiter plate and overnight cultures of each strain was added. Wells without bacterial culture were used as controls. A villous cap was then placed on the plate and incubated for 48 h at 37°C. During incubation, the biofilms formed on the surface of the villi of the caps. For quantification of biofilm formation, material that remained attached to the cap was stained with crystal violet, the stained biofilm was extracted and the OD570 of each well was measured. Each strain was classified as non-biofilm forming, weak forming, moderately formed or formative strong. Strong forming and non-biofilm forming strains were tested on high density polyethylene, stainless steel and glass surfaces. Plates of 4 cm² of the different materials were placed in TSB where the culture of each isolate was inoculated separately.[...]

Good hygienic practices and identification of contamination sources in Hotel Food and Beverage sector

This study aimed to evaluate the application of good practices in hotel restaurants in Southern Brazil, relate these practices to the microbiological quality of the food offered, in addition to identifying contamination sources. The food and beverage sector of four hotels was evaluated by means of a checklist based on the Resolution 216/2014 of Agência Nacional de Vigilância Sanitária and microbiological analyzes. Surface, utensil, equipment and handlers' hand samples were collected for coagulase positive Staphylococcus and thermotolerant coliform count. Isolates obtained from these culture counts were compared by band profiles obtained by rep-PCR. According to non-conformities observed, only one hotel was rated as excellent in good practices avaliation. Some microbiological analysis exceeded the allowed limit for the analyzed microorganism count, revealing failure in the hygiene-sanitary process. Genetic similarities between some food samples and handlers' hands and utensils were identified. These results showed inadequacies in the process of food care and handling which may compromise the quality of food offered to custumers.(AU)