Rice starch modification by thermal treatments with avocado oil: Autoclave versus microwave methods.

This study aimed to evaluate the physical and chemical alterations in rice starch modified by heat-moisture treatment (HMT) using an autoclave and a microwave, in association with avocado oil (AO), and evaluate the effects on thermal and structural properties, in vitro digestibility, and estimated glycemic index (eGI). Samples were adjusted to 30 % (w/w) moisture and 2, 4 and 8 % AO. HMT was conducted at 110 °C for 1 h in the autoclave (A0%, A2%, A4%, and A8%) and at 50 °C for 3 min in the microwave (M0%, M2%, M4%, and M8%). Both procedures did not alter the starch crystallinity pattern (type-A). Pasting viscosity, setback, relative crystallinity, and gelatinisation enthalpy decreased as the AO content increased in both HMT processes. The M8% showed reduced digestibility, decreased eGI (72.99, p < 0.05), and lower starch hydrolysis concentration (62.75 %, p < 0.05). The application of HMT with the addition of AO may be an interesting process for obtaining resistant starch since its content increased after both treatments (A8%, M4%, and M8%). The microwave process proved efficient, making it possible to use a lower temperature, less time, and less energy for modification and obtain starches with improved characteristics.

Encapsulation of propolis extract in ovalbumin protein particles: characterization and in vitro digestion.

The encapsulation of propolis has shown promising results for the protection of bioactive compounds, local and gradual release and masking the astringent taste. Ovoalbumin is a protein of animal origin found in large amounts in egg whites, which has good properties as a wall material for particles.The objective of this study was to microencapsulate propolis by spray drying. The best condition for microencapsulation was achieved with 4% ovalbumin at 120 °C, where there was the greatest encapsulation efficiency (88.20%) and spherical shape. However, the increase of ovalbumin concentration resulted lower yields (< 52%). As for the scanning electron microscopy (SEM), the increase of ovalbumin concentration caused an increase of the size with average diameter and formation of spherical microcapsules. The phenolic compounds were already released in the gastric fluid condition (stomach).

Stable isotope data and radiocarbon dates from Brazilian bioarchaeological samples: An extensive compilation.

Three decades have passed since the publication in 1991 of the first use of stable isotope analysis applied to a Brazilian archaeological context. Despite being still mainly applied to palaeodietary research, stable isotope analysis in archaeology has been diversified in Brazil. In the last five years, an increasing number of studies has addressed various issues. Such issues are related to population mobility, social differentiation, health and children care, changes and resilience of cultural practices, and identification of the origin of enslaved populations brought by force from the African continent, among others. However, research in this area is still incipient when compared to the large territory of Brazil (WGS 84: -33˚ to 5°N, -73˚ to -34˚E), the diversity of socio-cultural contexts of pre-colonial and indigenous societies, and the country's historical formation process. In terms of radiocarbon dates, data are also sparse and lack essential information as the material used for dating, as this information could be related to necessary corrections, e.g., the marine reservoir effect. The first radiocarbon dates of Brazilian archaeological material are reported, however, since the 1950s and have been more frequently reported in publications across Brazil since the installation of the first Brazilian radiocarbon laboratory (CENA/USP) in 1990 and the first Latin American 14C-AMS facility (LAC-UFF) in 2012. Thus, the purpose of this compilation was to gather all dispersed, and often fragmented, data from analyses of stable and radioactive (focusing on radiocarbon) isotopes carried out in Brazilian archaeological contexts. We compiled data from 1991 until the end of November 2021. The data included here contain information from 71 archaeological sites, 556 humans, 219 animals and 2 plants. Isotopic analyses were performed on 832 organic samples, mainly paired δ13C and δ15N plus δ34S measurements, and on 265 mineral samples, mainly δ13C, δ18O and 86Sr/87Sr measurements. Sr concentrations for 49 mineral samples were also compiled. Radiocarbon or relative dates span from 18 kyr BP to the present. All data from this compilation are deposited in open access on the IsoArcH platform (https://doi.isoarch.eu/doi/2021.005). This extensive work aims to point out the gaps in stable isotopes and radiocarbon dates provided for Brazilian archaeological contexts that could be further explored. Besides, it aims to promote easy access to numerous analyses that, otherwise, would be hard to obtain. Lastly, it seeks to broaden the interdisciplinary collaboration in Brazil and strengthen the international collaboration among peers.

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.

Thermal stability of avocado oil: A comparative study with rice bran and olive oils

ABSTRACT This study aimed to evaluate the thermal stability of avocado oil (Breda variety) compared to olive and rice bran oils. The oils were heated to a temperature of 180 °C for 1.5, 3.0, 4.5, and 6.0 h in a digester block. The evaluations performed were: acidity, indices of peroxides, iodine, p-anisidine, refraction, electrical conductivity, specific extinction coefficients, phenolic compounds, chlorophylls, carotenoids, and antioxidant activity of the samples. Changes in the evaluated parameters were found as a function of the heating time. In general, olive oil was found to be more stable, followed by avocado oil. However, the avocado oil showed good maintenance of characteristics when subjected to heating. This work has shown that avocado oil is very similar to olive oil and that both show considerable stability after heating at the usual temperature of the frying process.

RESUMEN El objetivo de este estudio fue evaluar la estabilidad térmica del aceite de aguacate (variedad Breda) en comparación con los aceites de salvado de arroz y oliva. Se calentaron los aceites a una temperatura de 180 °C durante 1,5; 3,0; 4,5 y 6,0 h en un bloque digestor. Las muestras fueran sometidas a los siguientes análisis: acidez, índices de peróxidos, yodo, p-anisidina, refracción, conductividad eléctrica, coeficientes de extinción específica, compuestos fenólicos, clorofilas, carotenoides y actividad antioxidante. Se encontraron cambios en los parámetros evaluados en función del tiempo de calentamiento. Por lo general, se encontró que el aceite de oliva es más estable, seguido del aceite de aguacate. Sin embargo, el aceite de aguacate mostró un buen mantenimiento de las características bajo el calentamiento. Este trabajo ha demostrado que el aceite de aguacate es muy similar al aceite de oliva y que ambos muestran una estabilidad considerable al calentar a la temperatura habitual del proceso de fritura.

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.

Aerogels based on corn starch as carriers for pinhão coat extract (Araucaria angustifolia) rich in phenolic compounds for active packaging.

The objective of this study was to produce renewable aerogels from native and anionic corn starches loaded with pinhão coat extract (PCE) with water absorbent capacity, antioxidant activity and controlled release of phenolic compounds in a hydrophilic food simulant media. Starch aerogels were produced with different concentrations of PCE, 5 and 10%, and evaluated for FT-IR spectra, relative crystallinity, thermal properties, water absorption capacity (WAC), density, antioxidant activity and in vitro release. Thermal stability of the compounds was improved by the incorporation of PCE. The aerogels presented high WAC of 541 to 731% and low-density values of 0.03 g.cm-1. The highest inhibition of DPPH and ABTS radicals was presented to anionic starch aerogels with 10% PCE rendering 26% of inhibition of ABTS and 24% of DPPH. The maximum in vitro releases for native and anionic starch aerogels with 5% of PCE were 28.70 and 29.44%, respectively, and for aerogels with 10% of PCE they were 34.27 and 35.94%, respectively. The anionic starch aerogels had the highest amount of phenolic compounds released when compared to the native starch aerogels. The starch-based bioactive aerogels showed potential to be applied in food packaging as water absorbent and as a carrier of phenolic compounds.

Application of microemulsions as coating in fresh cut strawberries.

The objective of this study was to evaluate microemulsions as a protective coating for fresh cut (FC) strawberries. The effectiveness of the coating was evaluated by physicochemical, fungal deterioration, and sensorial analysis. The fruits were processed and submitted to different treatments: control (T1); microemulsion with citronella oil (T2); pure microemulsion (T3); microemulsion with avocado oil (T4), and emulsion containing Tween® 20 and avocado oil in water (T5). The loss of mass, deterioration by fungi, color, and anthocyanin content were evaluated. Sensory analysis was carried out for appearance, brightness, color, and odor. Of all the evaluated coatings, conservation of FC strawberries was the highest with T5, wherein the evaluated sample exhibited reduced loss of mass and deterioration by fungi, minimal changes in physical appearance, and highest anthocyanin content. The avocado oil-containing microemulsion reduced deterioration by fungi, while the microemulsion with citronella essential oil maintained tonality of the fruits and preserved anthocyanins. This study has significantly contributed to the limited literature-based information available about MEs in the food.

Cone-beam and micro-computed tomography for the assessment of root canal morphology: a systematic review.

This study presents an overview of the accuracy of cone beam computed tomography (CBCT) compared with micro-computed tomography (µCT) in the assessment of root canal morphology of extracted human permanent teeth. A database search in PubMed, PubMed Central, Embase, Scopus, Opengrey, Scielo and Virtual Health Library was conducted which compared root canal morphology of extracted human permanent teeth on the accuracy of CBCT with µCT. In accordance with PRISMA statement guidelines, data were extracted on study characteristics, target mediators, sampling and assay techniques and the parameters associated with obtaining the image and ability to identify the root canal morphology. Amongst 2734 records, ten fulfilled the inclusion criteria. Four studies compared the accuracy of CBCT and µCT in the assessment of root canal morphology using Vertucci's classification, with at least one CBCT group or subgroup of each study presented high agreement compared to the µCT. Six studies assessed more detailed root canal morphology, including two articles that found a lack of agreement between these imaging systems. Risk of bias was deemed low in three studies, moderate in four and high in three. CBCT can be as accurate as µCT in the assessment of several morphological features of extracted human permanent teeth; however there are some exceptions related to the more detailed morphological aspects. Voxel size likely influences the ability to detect these features, though the different aspects of exposure setting used in studies components may be confounding factors. CBCT may be considered for the assessment of root canal morphology ex-vivo.

The Effect of Diode and Er,Cr:YSGG Lasers on the Bond Strength of Fiber Posts.

Background: Laser irradiation modifies the topography and composition of dentin surface aiming to increase the retention of bonded posts. Objective: To assess the effect of dentin irradiation with Er,Cr:YSGG or diode lasers on the bond strength of fiber posts using self-adhesive resin cement. Materials and methods: Sixty bovine root canals were root-canal treated, post spaces were prepared, and subsequently fiber posts were cemented. The samples were distributed according to the surface treatment: distilled water (control), Er,Cr:YSGG (1.5 W, 20 sec), or diode (1.5 W, 20 sec) lasers. Bond strengths were assessed by pull-out (n = 10) or push-out testing (n = 10). Pearson's correlation was calculated. Failure mode after testing and the depth of tags in the dentinal tubules were analyzed by confocal laser microscopy. Data were submitted to analysis of variance and Tukey's test. A p < 0.05 was considered significant. Results: In the push-out test, Er,Cr:YSGG laser had significantly different higher values (5.43 ± 0.10 MPa) compared to the control (4.79 ± 0.05 MPa). Diode laser values were not significantly different from the other groups (5.12 ± 0.27 MPa). In the pull-out test, there were no significant differences between Er,Cr:YSGG (6.86 ± 2.16 MPa) and diode (8.43 ± 1.77 MPa) lasers, and both had significant differences compared to the control (4.18 ± 1.29 MPa). No correlation was found. Adhesive failures were predominant in all groups, and no significant differences in tag penetration among the groups were found. Conclusions: The Er,Cr:YSGG laser increases the bond strength of resin cement and fiber post to dentin in both tests, compared to control group without laser treatment. Diode laser only enhanced bonding for pull-out test.

Cone-beam and micro-computed tomography for the assessment of root canal morphology: a systematic review

Abstract This study presents an overview of the accuracy of cone beam computed tomography (CBCT) compared with micro-computed tomography (μCT) in the assessment of root canal morphology of extracted human permanent teeth. A database search in PubMed, PubMed Central, Embase, Scopus, Opengrey, Scielo and Virtual Health Library was conducted which compared root canal morphology of extracted human permanent teeth on the accuracy of CBCT with μCT. In accordance with PRISMA statement guidelines, data were extracted on study characteristics, target mediators, sampling and assay techniques and the parameters associated with obtaining the image and ability to identify the root canal morphology. Amongst 2734 records, ten fulfilled the inclusion criteria. Four studies compared the accuracy of CBCT and μCT in the assessment of root canal morphology using Vertucci's classification, with at least one CBCT group or subgroup of each study presented high agreement compared to the μCT. Six studies assessed more detailed root canal morphology, including two articles that found a lack of agreement between these imaging systems. Risk of bias was deemed low in three studies, moderate in four and high in three. CBCT can be as accurate as μCT in the assessment of several morphological features of extracted human permanent teeth; however there are some exceptions related to the more detailed morphological aspects. Voxel size likely influences the ability to detect these features, though the different aspects of exposure setting used in studies components may be confounding factors. CBCT may be considered for the assessment of root canal morphology ex-vivo.

A CAD/CAM-based strategy for concurrent endodontic and restorative treatment.

This case report describes a technique in which endodontic treatment and permanent indirect restoration were completed in the same clinical appointment with the aid of a computer-aided design/computer-aided manufacturing (CAD/CAM) system. Two patients were diagnosed with irreversible pulpitis of the mandibular first molar. After access preparation, root canals were located, irrigation was performed until bleeding ceased, and the coronal tooth structure was prepared for indirect restoration. Then, utilizing an interim 3-mm build-up of the endodontic access cavity, a hemi-arch digital scan was performed with an intraoral scanner. Subsequent to digital scanning, restoration design was performed simultaneously with the endodontic procedure. The root canals were shaped using the Race system under irrigation with 2.5% sodium hypochlorite followed by root canal filling. The pulp chamber was subsequently filled with a 3-mm-thick composite resin restoration mimicking the interim build-up previously utilized to facilitate block milling in the CAD/CAM system. Clinical try-in of the permanent onlay restoration was followed by acid etching, application of a 5th generation adhesive, and cementation of the indirect restoration. Once the restoration was cemented, rubber dam isolation was removed, followed by occlusal adjustment and polishing. After 2 years of follow-up, the restorations were esthetically and functionally satisfactory, without complications.

Avaliação do estado oxidação dos óleos de abacate, azeite e arroz / Oxidation state evaluation of the avocado, olive and rice oils

O estado de oxidação é um importante aspecto relacionado à qualidade nutricional e sensorial dos óleos vegetais, que pode limitar a utilização dos mesmos. Assim, objetivou-se com este estudo avaliar o estado oxidação de óleo de abacate produzido nacionalmente, comparativamente a azeite de oliva extra virgem e a óleo de arroz refinado. Avaliaram-se nos produtos os índices de peróxidos, p-anisidina e coeficiente de extinção específica (K232 e K270). Os resultados indicaram que, de um modo geral, as amostras lipídicas mostravam bom estado de conservação, tanto em relação a produtos primários quanto secundários de oxidação. Entretanto, com base na legislação para azeite de oliva, pode-se inferir que o óleo de arroz apresentava elevado valor para produtos de oxidação secundários, expressos pelo K270. O óleo de abacate mostrou os mais baixos valores em todas as determinações realizadas, portanto, indicando estar em ótimo estado de conservação em relação à presença de produtos de oxidação.

Efeito da forma de aquecimento em parâmetros de qualidade e identidade de óleos vegetais / Effect of the heating means in quality and identity parameters of vegetable oils

Objetivou-se com este trabalho avaliar parâmetros de identidade e qualidade de óleo de abacate produzido nacionalmente, comparativamente a azeite de oliva e óleo de arroz, após aquecimento em bloco digestor ou micro-ondas. Avaliaram-se amostras sem aquecimento (controle) e aquecidas por 1:30 h em bloco digestor ou 3 min em micro-ondas. Determinaram-se a acidez e os índices iodo e refração. Os resultados indicaram que houve aumento de acidez, redução no índice de iodo e índice de refração após o aquecimento. Apesar do maior valor de acidez após o aquecimento, o óleo de abacate sofreu menor elevação em relação ao controle (cerca de 4 vezes) do que as demais amostras. O impacto do aquecimento foi maior no óleo de arroz, seguido do azeite de oliva. O aquecimento por micro-ondas afetou mais a qualidade das amostras que o aquecimento em bloco digestor.

Estabilidade térmica de pigmentos em óleo de abacate, arroz e azeite de oliva / Thermal stability of pigments in avocado, rice and olive oil

Sabe-se que o aquecimento do óleo pode alterar sua composição, degradando ácidos graxos e compostos minoritários. Assim, objetivou-se avaliar a estabilidade térmica dos pigmentos carotenoides e clorofilas no óleo de abacate produzido nacionalmente, em comparação com óleo de arroz e azeite de oliva após aquecimento a 180 ºC em micro-ondas, por 3, 6, 9 e 12 minutos. Observaram-se diferenças significativas entre as amostras em todos os tempos de análise, tanto para clorofilas quanto para carotenoides. Na avaliação ao longo do tempo de aquecimento somente foi verificada alteração significativa no teor de clorofilas do azeite de oliva, ainda que no óleo de abacate os percentuais de perda tenham sido maiores. Verificou-se que os teores dos pigmentos avaliados foram significativamente maiores no óleo de abacate em relação ao azeite de oliva e o óleo de arroz, mesmo após o aquecimento por 12 minutos. Destaca-se a importância destas informações para estimular o consumo do óleo de abacate.

Influência da luminosidade na firmeza e perda de massa de pinhões / Influence of luminosity on firmness and loss of mass of pinhões

As sementes de Araucaria angustifolia, conhecidas como pinhão, tem sua conservação pós-colheita dificultada. A germinação do pinhão representa uma desvantagem, já que sementes brotadas não tem valor comercial. A inibição da germinação pela luz induz a semente ao seu estado de dormência, com redução da atividade metabólica, sendo uma alternativa para a conservação da semente. Com isso, objetivou-se neste estudo avaliar a perda de massa e firmeza de pinhões armazenados sob diferentes condições de luminosidade a temperatura ambiente por 90 dias. O armazenamento de pinhões em diferentes condições de luminosidade a temperatura ambiente ocasionou perda de massa e firmeza, sendo que a luminosidade não proporcionou aumento da conservação de pinhões.

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.

Bioactive compounds and quality parameters of avocado oil obtained by different processes.

The objective of this study was to evaluate the quality of avocado oil whose pulp was processed through different drying and oil extraction methods. The physicochemical characteristics of avocados cv. Breda were determined after drying the pulp in an oven under ventilation (40 °C and 60 °C) and vacuum oven (60 °C), followed by the oil extracted by mechanical pressing or the Soxhlet method. From the approximately 72% pulp found in the avocado fruit, the 16% fraction is lipids. The quality indices evaluated in avocado oil showed better results when the pulp was dried at 60 °C under vacuum and oil extraction was done by the Soxhlet method with petroleum ether, whereas the bioactive compounds were better preserved when the avocado pulp was dried at 60 °C under ventilation and mechanical pressing was used for the oil extraction. Among the fatty acids found, oleic acid was the main.

Effect of nanoencapsulation using PLGA on antioxidant and antimicrobial activities of guabiroba fruit phenolic extract.

Guabiroba fruit has been highlighted for its high phytochemical content, particularly of phenolic compounds. The stability, bioavailability, and bioactivity of these compounds can be enhanced by nanoencapsulation, to improve functionality. Poly(d,l-lactic-co-glycolic) acid (PLGA) nanoparticles containing phenolic extract of guabiroba (GPE) were synthesized by an adapted emulsion-evaporation method and their physico-chemical and functional properties were studied at two lactic to glycolic acid ratios (50:50 and 65:35). Higher (P<0.05) or equivalent antioxidant capacity compared to free GPE were observed for GPE-loaded nanoparticles. Free extract and PLGA nanoparticles were effective inhibitors of Listeria innocua, with lower (P<0.05) GPE concentrations required for inhibition when nanoencapsulated. Also, reduction of ROS generation in non-cancer cells was achieved with lower GPE concentrations (P<0.05) after encapsulation. These results suggest that PLGA nanoparticles can be used as a delivery system for phenolic compounds at lower levels than originally required for enhanced functional properties.