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Legumes are abundant sources of proteins, and white common bean proteins play an important role in air-water interface properties. This study aims to investigate the technical-functional properties of white common bean protein isolate (BPI) as a function of pH, protein concentration, and guar gum (GG) presence. BPI physicochemical properties were analyzed in terms of solubility, zeta potential, and mean particle diameter at pH ranging from 2 to 9, in addition to water-holding capacity (WHC), oil-holding capacity (OHC), and thermogravimetric analysis. Protein dispersions were evaluated in terms of dynamic, interfacial, and foam-forming properties. BPI showed higher solubility (>80 %) at pH 2 and above 7. Zeta potential and mean diameter ranged from 15.43 to -34.08 mV and from 129.55 to 139.90 nm, respectively. BPI exhibited WHC and OHC of 1.37 and 4.97 g/g, respectively. Thermograms indicated decomposition temperature (295.81 °C) and mass loss (64.73 %). Flow curves indicated pseudoplastic behavior, with higher η100 values observed in treatments containing guar gum. The behavior was predominantly viscous (tg δ > 1) at lower frequencies, at all pH levels, shifting to predominantly elastic at higher frequencies. Equilibrium surface tension (γeq) ranged from 43.87 to 41.95 mN.m-1 and did not decrease with increasing protein concentration under all pH conditions. All treatments exhibited ϕ < 15°, indicating predominantly elastic surface films. Foaming properties were influenced by higher protein concentration and guar gum addition, and the potential formation of protein-polysaccharide complexes favored the kinetic stability of the system.

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This study focuses on optimizing the ultrasound-assisted extraction (UAE) of bioactive compounds from purple-fleshed sweet potatoes (PFSP) for potential use as natural colorants. Factors such as time, temperature, and solid-to-liquid ratio were varied using a Box-Behnken Design. The optimal conditions were determined as 75 min, 70 °C, and a 1:15 m/v solid-to-liquid ratio, resulting in 18.372 mg/100 g total anthocyanin (TA) and 151.160 mg GAE/100 g total phenolic content (TPC). The validation yielded 18.822 mg/100 g for total anthocyanin and 162.174 mg GAE/100 g for total phenolic content, showing a 7% difference from predictions. UAE significantly increased TA extraction by 81% and TPC by 93% compared with the conventional method, with a notable reduction in process time from 24 h to 75 min. Additionally, three kinetic models were tested to compare extraction mechanisms, confirming the efficiency of UAE for PFSP bioactive compound recovery. This study proposes the UAE technique as a highly effective means of extracting bioactive compounds from PFSP, offering promising applications across multiple industries.

RESUMO

Sorghum 3-deoxyanthocyanins (3-DXAs) have greater stability when compared to other anthocyanins. However, the efficiency in extracting these phenolic compounds from cereals, using conventional methods, is low, because most of them are bound to the cell wall. Thus, the aim of this study was to optimize the ultrasound-assisted extraction (UAE) of anthocyanins and total phenolics from sorghum flour, and evaluate the stability of the 3-DXAs. Two frequencies (25 and 45 kHz) were applied in a Central Composite Rotational design to investigate the effect of the variables time (5-75 min) and temperature (30-65°C) using the UAE, with amplitude of the ultrasonic power set at 400 W. In addition, the stability of the 3-DXAs present in the extracts was evaluated. It was possible to successfully optimize the extraction of total anthocyanins (both frequencies) and phenolics (at 45 kHz), and then to obtain equations, to predict their concentrations, with high R2 . The efficiency of UAE was observed, increasing the yield of total anthocyanins, phenolics, and antioxidant capacity at the frequencies of 25 and 45 kHz by 30% and 27%, 10% and 5%, and 30% and 15%, respectively. The apigeninidin was the major 3-DXA found in the extracts, and the luteolinidin was the most stable over storage time. Overall, there was no difference in the 3-DXAs stability obtained by the UAE compared to the conventional method. Thus, ultrasound is an alternative to obtaining sorghum extracts rich in 3-DXAs and other phenolic compounds. PRACTICAL APPLICATION: The health benefits of sorghum 3-deoxyanthocyanins coupled with the growing interest of the food industry in producing healthier food products have motivated this study, because it is important to find ways to optimize 3-deoxyanthocyanins extraction. We have demonstrated that ultrasound-assisted extraction was efficient in extracting high amounts of 3-deoxyanthocyanins and other phenolics from sorghum flour. Moreover, some 3-deoxyanthocyanins have shown to be more stable than others after extraction. Thus, the ultrasound has great potential to produce sorghum phenolic extracts rich in 3-deoxyanthocyanins, which can be used as natural colorants and functional ingredients in foods.

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The oil extracted from baru (Dipteryx alata Vog.) seeds is in bioactive compounds and it presents potential to be used in food and cosmetic industries. Therefore, this study aims to provide insights into the stability of baru oil-in-water (O/W) nanoemulsions. For this purpose, the effects of the ionic strength (0, 100 and 200 mM), pH (6, 7 and 8), and storage time (28 days) on the kinetic stability of these colloidal dispersions were evaluated. The nanoemulsions were characterized in terms of interfacial properties, rheology, zeta potential (ζ), average droplet diameter, polydispersity index (PDI), microstructure, and creaming index. In general, for samples, the equilibrium interfacial tension ranged from 1.21 to 3.4 mN.m-1, and the interfacial layer presented an elastic behavior with low dilatational viscoelasticity. Results show that the nanoemulsions present a Newtonian flow behavior, with a viscosity ranging from 1.99 to 2.39 mPa.s. The nanoemulsions presented an average diameter of 237-315 nm with a low polydispersity index (<0.39), and a ζ-potential ranging from 39.4 to 50.3 mV after 28 days of storage at 25 °C. The results obtained for the ζ-potential suggest strong electrostatic repulsions between the droplets, which is an indicative of relative kinetic stability. In fact, macroscopically, all the nanoemulsions were relatively stable after 28 days of storage, except the nanoemulsions added with NaCl. Nanoemulsions produced with baru oil present a great potential to be used in the food, cosmetic, and pharmaceutical industries.

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The objective of this study was to examine the effects of emulsifying agents on processing and texture characteristics of kibbles in the pet food industry. For each treatment, four runs were performed (four replications/treatment) and four samples were collected over time. Two commercial emulsifiers, added on top of the formulation, were used in an economical extruded dry food for adult dogs, forming three treatments, namely, CON: control; EMUA: CON + 0.06% emulsifier A; and EMUB: CON + 0.06% emulsifier B. The foods were extruded in a single-screw extruder with a throughput of 6,000 kg/h, and the same set of equipment, mixing, drying, and coating conditions were adopted for all treatments. Emulsifier A contains partially saturated mono- and diglycerides, sodium stearoyl lactylate, and diacetyl tartaric acid esters of monoglycerides in its composition; whereas emulsifier B includes mono- and diglycerides of fatty acids, diacetyl tartaric acid esters of monoglycerides, and stearoyl sodium lactate. Canonical correlation analysis was performed for process correlation and kibble texture characteristics data. The multivariate lambda Wilks test was used to assess the significance of the canonical roots together. Canonical function 1 was found to be significant. There was control in the process, due to the clustering of treatments. The use of emulsifiers influenced the hardness of the kibbles, with lower resistance found in EMUA (54.731 ± 1.124) than in EMUB (121.898 ± 5.158). The EMUB treatment showed lower amperage, power, and energy consumption values than the other treatments (P<0.05). Compared with the control treatment, the EMUA and EMUB treatments showed 1.43% and 3.15% lower amperage values, respectively. In conclusion, EMUB contributes more significantly to texture characteristics and to the extrusion process.(AU)

Objetivou-se com essa pesquisa avaliar os efeitos de aditivos emulsificantes em características de processo e textura dos kibbles na indústria pet food. Para cada tratamento, foram realizadas quatro batidas (4 repetições/tratamento) e coletadas quatro amostras no tempo. Dois emulsificantes comerciais, adicionados on top, foram utilizados em um alimento seco extrusado, indicado para cães adultos, formando 3 tratamentos ((CON; Controle), (EMUA; CON + 0,06% emulsificante A), (EMUB; CON + 0,06% emulsificante B)). Foi utilizada dieta comercial econômica para cães adultos. Os alimentos foram extrusados em uma extrusora de rosca simples, com capacidade de processamento de 6.000 kg/h, sendo que o mesmo conjunto de equipamentos, condições de mistura, secagem e revestimento foram utilizados para todos os tratamentos. O emulsificante A possui em sua composição mono-diglicerídeo parcialmente saturado, estearoil lactato de sódio e mono éster de ácido tartárico di-acetilado, enquanto o emulsificante B possui em sua composição mono e diglicerídeos de ácidos graxos, ésteres de monoglicerídeos com ácido diacetiltartárico e estearoil lactato de sódio. Foi realizada uma análise de correlação canônica para os dados de correlação de processos e características de textura de kibble. O teste multivariado lambda Wilks foi usado para avaliar a significância das raízes canônicas juntas. Observou-se que a função canônica 1 mostrou-se significante. Percebeu-se que houve controle no processo, devido ao agrupamento dos tratamentos. A utilização de emulsificantes influenciou a característica de dureza dos kibbles, com menor resistência de EMUA (54,731 ±1,124), quando comparado a EMUB (121,898± 5,158). O tratamento EMUB obteve valores de amperagem, potência e consumo de energia inferiores aos demais tratamentos (P<0,05). Houve uma redução no valor da Amperagem, em relação ao tratamento CON de 1,43% e 3,15%, respectivamente, para os tratamentos EMUA e EMUB. Conclui-se que EMUB contribui mais significativamente para obtenção de características de textura e para o processo de extrusão.(AU)

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The Covid-19 pandemic has strongly impacted people's lives and the food industry. In this sense, food products claiming nutritional and health-promoting benefits due to the presence of bioactive peptides and probiotics, such as Greek-style yogurt, have been in demand. The objective of this work was to investigate, through word association, the perception of the consumers regarding the seven concepts related to Greek-style yogurt (traditional, ultra-creamy, zero fat, high content proteins, zero lactose, light and with no added sugars), in the context of social isolation due to Covid-19. In this online survey, 346 participants completed a questionnaire. The participants were divided according to health concerns (increased, not changed, or decreased) and eating habits (improved, not changed, or worsened) during the Covid-19 pandemic. Chi-square and prototypical analysis were used as statistical tests. During the Covid-19 pandemic, based on self-report, around 66% of the participants had their eating habits and their concerns about health changed. The general associations were related to the categories pleasure, health, creamy, pleasant texture, food restriction, and loss of sensory quality. 'Health' and 'pleasure' were negatively associated with the conceptualization of Greek-style yogurt. For the zero-fat, light, and sugar-free Greek-style yogurts, the terms creamy and ultra-creamy are sensory appealing to the consumers. In general, the price and concerns about health are factors that strongly influence the purchase intention of Greek-style yogurts. The yogurts were associated with sensory and non-sensory characteristics, which can be useful for marketing strategies for of different product concepts.

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Red beetroot (Beta vulgaris L.) is a great source of betalains. The main betalains are the betacyanins, responsible for the purple color, and betaxanthins, which present a brownish color. These pigments can present antioxidant activity and are very unstable under certain conditions, such as temperature, extreme ranges of pH, and exposure to light. The aim of this work was to obtain beetroot extract (BE) via ultrasound and transform it into nanoparticles by using polyethylene glycol (PBE) and polyethylene glycol with low molecular weight chitosan (PCBE) as dispersants. The stability of the main betalains in the nanodispersions and the effects of the nanodispersions on the color and rheological properties of commercial Greek yogurt were evaluated. Compared to pristine BE, PCBE nanoparticles presented increased stability for the main betalains in acidic conditions (pH 3.0 and 5.0) of 56% and 22%, respectively. Both PBE and PCBE showed enhanced relative thermal stability compared to pristine BE. Furthermore, PCBE improved commercial Greek yogurt's rheological properties and color parameters. PCBE nanodispersions can be successfully applied as a color additive to commercial Greek yogurt.

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Despite some thermodynamics studies about ß-lactoglobulin (ßLG) and resveratrol (RES) interactions, there is a gap regarding kinetics data about ßLG-RES complex formation. Here, we determined the kinetic and thermodynamic parameters of ßLG-RES interactions by using surface plasmon resonance (SPR). The kinetic association parameters were dependent on the 3D water structure present on the solvation shell of both interacting molecules. At lower temperature (285.15 K), all activation energies were positive (Eacta‡= 82.86 kJ.mol-1,TΔSa‡= 32.26 kJ.mol-1, and ΔCpa‡= 4.15 kJ.mol-1K-1) due to the higher water structuration on the RES and ßLG solvation shell. All these energetic barriers become mainly from the energetic cost for the desolvation process of RES and ßLG. At higher temperature (301.15 K), the solvation water structure decreases and all the above activation energies become negative (Eacta‡=-121.58 kJ.mol-1,TΔSa‡=-173.59 kJ.mol-1, and ΔCpa‡=-29.92 kJ.mol-1K-1) because the direct interaction between desolvated RES and ßLG molecules released more energy than it is absorbed by desolvation process. However, kinetic dissociation parameters were not dependent on the hydrogen bond density of the water solvation shell as showed by the temperature independence of dissociation energetic parameters. This non-dependence of the dissociation process from the desolvation step probably is because the water molecules interacting with the ßLG-RES complex is not concentrated around/inside the protein site of interaction. The association of free molecules was 1.5 times faster than the dissociation of the thermodynamically stable complex (ΔG(a)‡â€¯â‰… 48.15 kJ.mol-1, ΔG(d)‡â€¯â‰… 73.10 kJ.mol-1). The lower free energy barrier observed for the association came from an isokinetic process where entropic and enthalpic parameters compensated for each other. The ΔG° values indicate that the thermodynamically stable complex predominates over free molecules. At low temperature (285.15 K), the hydrophobic interaction (ΔH° = 73.06 kJ.mol-1; TΔS° = 99.60 kJ.mol-1) drove the ßLG-RES complex formation while at high temperature (301.15 K), hydrophilic interactions became dominant (ΔH° = -142.50 kJ.mol-1; TΔS° = -118.18 kJ.mol-1).

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This study focused on the extraction, purification, and physicochemical characterization of γ-conglutin, a protein present in lupin seeds with properties of reducing blood glucose levels. Total protein was extracted with an alkaline-saline solvent, followed by isoelectric precipitation. Chromatographic purification of the precipitated fraction was performed using a cation exchange supermacroporous cryogel column. Electrophoresis of the eluted fraction from chromatography presented a single band of ∼48 kDa under non-reducing conditions (two bands of ∼30 and ∼17 kDa, under reducing conditions) confirming the success of the purification protocol. Liquid chromatography-tandem mass spectrometry analysis confirmed the identity of the protein as γ-conglutin. The purified γ-conglutin had an isoelectric point of 7.51, ß-sheets prevailing as a secondary structure, and denaturation temperature close to 68°C. The outcome of this work showed that γ-conglutin was obtained with a high degree of purity. The proposed purification protocol is simple and can be easily scaled up.

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This article presents a study of the interfacial properties of oil-in-water emulsions containing sugar esters and polysaccharides. Sucrose fatty acid esters were synthesized using immobilized Candida antarctica lipase B. A yield of 53.4% was obtained using 2-methyl-2-butanol and 1:3 M ratio of sucrose:stearic acid. Equilibrium surface tension was 45 mN/m and low critical micellar concentration (CMC) value was obtained (ca. 10 mg/mL), characteristic of non-ionic surfactant. The interfacial properties of mixtures of sucrose esters and polysaccharides, at the oil-water interface were determined using a pendant drop tensiometer. Addition of polysaccharides increased the interfacial tension. Studies of interfacial viscoelasticity showed that the films were predominantly elastic. The presence of polysaccharides in emulsions resulted in flocculated droplets. All the emulsions presented great stability along 28 days with no creaming formation.

RESUMO

The aim of this study was to evaluate the visceral composition, cuts, and meat quality of two strains of free-range chickens fed diets containing crushed sugar cane. 448 chickens were distributed at 35 days of age, in two randomized blocks design, in 4x2 factorial, with four levels of replacement in the feed (0; 15; 30 and 45%) by sugarcane and two strains (Pesadão and Label Rouge), in two repetitions per block of fourteen birds per experimental unit. In 30 minutes after slaughter, the parameter a* was higher for animals of the Pesadão strain relation to the Label Rouge lineage. A quadratic effect was observed with increasing levels of sugarcane on the L* parameter of breast meat; and linear effect on parameter b* of the breast skin. Within 24 hours after slaughter, a quadratic effect of sugarcane levels was observed on the b* parameter of the breast meat. The increase in sugarcane levels linearly reduced the weight of heart, liver, chest, thigh plus drumstick, wing, carcass yield and relative heart weight of the animals. A quadratic effect was observed with increase in sugarcane levels over the relative weight of abdominal fat, the lowest fat content was observed in animals that consumed up to 30% of sugarcane in the feed. The use of sugarcane as an alternative feedstuff in up to 45% in the diet maintains the quality of meat and reduces the abdominal fat content, however, decreases the carcass yield.(AU)

Objetivou-se com este trabalho avaliar a composição visceral, o rendimento de cortes e a qualidade de carne de duas linhagens de frangos tipo caipira alimentados com dietas contendo cana-de-açúcar triturada. Foram utilizados 448 frangos distribuídos, aos 35 dias de idade, em dois blocos casualizados, em esquema fatorial 4x2, sendo quatro níveis de substituição da ração (0; 15; 30 e 45%) por de cana-de-açúcar e duas linhagens (Pesadão e Label Rouge), em duas repetições por bloco de quatorze aves unidade experimental. Em 30 minutos após o abate, o parâmetro a* foi maior para os animais da linhagem Pesadão em relação à linhagem Label Rouge. Observou-se efeito quadrático com o aumento dos níveis cana-de-açúcar sobre o parâmetro L* da carne do peito; e efeito linear sobre o parâmetro b* da pele do peito. Em 24 horas após o abate, observou-se efeito quadrático dos níveis de cana-de-açúcar sobre o parâmetro b* da carne do peito. O aumento dos níveis de cana-de-açúcar reduziu linearmente o peso do coração, fígado, peito, coxa mais sobrecoxa, asa, rendimento de carcaça e peso relativo do coração dos animais. Observou-se efeito quadrático com o aumento dos níveis de cana-de-açúcar sobre o peso relativo da gordura abdominal, sendo que o menor teor de gordura foi observado nos animais que consumiram até 30% de cana-de-açúcar. O uso da cana-de-açúcar como alimento alternativo em até 45% na dieta, possibilita manter a qualidade de carne e reduz o teor de gordura abdominal, porém, diminui o rendimento de carcaça.(AU)

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Naringenin (NG) is a flavonoid with many bioactive properties, however, its bitterness limits its use in foods. It is known that complex formation with proteins can mask this undesirable sensory property. Therefore, a trained panel evaluated the effect of bovine lactoferrin (LF) on NG bitterness using time-intensity analysis. LF reduced the maximum bitterness intensity and overall bitterness perception for NG by 27% and 33%, respectively. Isothermal titration nanocalorimetry (ITC), molecular docking (DC), and molecular dynamics (MD) were used to characterize NG-LF binding. These techniques provided similar values of ΔG° for binding ( [Formula: see text]  = -33.42 kJ mol-1; [Formula: see text]  = -32.22 kJ mol-1; [Formula: see text]  = -31.84 kJ mol-1). ITC showed that the complex formation is primarily entropy driven and DC suggested that NG binds at a hydrophobic site in LF. Here are presented strategic tools for promoting NG incorporation in food and health products.

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Emojis can be used to explore food-evoked emotions in order to provide information that can support the product development and marketing decisions. This study aimed to evaluate consumers' acceptance, purchase intent and emotional responses to milk beverages, with and without kefir added, before and after these consumers were informed about the products' composition (0%, 15%, 30% and 50% m/v) and health claims toward kefir (blind and informed tests, respectively). Emotional responses were assessed by emoji use within a RATA questionnaire in order quantify the perceived significance of the emojis chosen. In the informed test, the consumers' perception of the sensory attributes of the milk beverages, such as their perception of an acid taste in added kefir beverages was shown to have changed. Overall, participants attributed significantly higher acceptance and purchase intent scores to added kefir beverages after they had been informed on its health benefits. In addition, expressions of positive emotion increased when participants were exposed to stimuli related to health benefits of kefir (15%, 30% and 50% m/v), while negative expressions of emotion decreased. The provided information of kefir modified valence and arousal in subjects, and it can be said that to 30% of kefir can be added to yogurt without compromising its sensory acceptability. Thus, health benefits alone cannot improve product acceptance, since participants found a 50% addition of kefir to be unpleasant when tasted during a blind test. Mixed beverages may present a probiotic beverage alternative for consumers who dislike kefir milk, but want to include it in their diets. The implications of liking and purchase intent and how they are linked to emotions are discussed in this paper as well.

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The aim of this study was to evaluate the visceral composition, cuts, and meat quality of two strains of free-range chickens fed diets containing crushed sugar cane. 448 chickens were distributed at 35 days of age, in two randomized blocks design, in 4x2 factorial, with four levels of replacement in the feed (0; 15; 30 and 45%) by sugarcane and two strains (Pesadão and Label Rouge), in two repetitions per block of fourteen birds per experimental unit. In 30 minutes after slaughter, the parameter a* was higher for animals of the Pesadão strain relation to the Label Rouge lineage. A quadratic effect was observed with increasing levels of sugarcane on the L* parameter of breast meat; and linear effect on parameter b* of the breast skin. Within 24 hours after slaughter, a quadratic effect of sugarcane levels was observed on the b* parameter of the breast meat. The increase in sugarcane levels linearly reduced the weight of heart, liver, chest, thigh plus drumstick, wing, carcass yield and relative heart weight of the animals. A quadratic effect was observed with increase in sugarcane levels over the relative weight of abdominal fat, the lowest fat content was observed in animals that consumed up to 30% of sugarcane in the feed. The use of sugarcane as an alternative feedstuff in up to 45% in the diet maintains the quality of meat and reduces the abdominal fat content, however, decreases the carcass yield.

Objetivou-se com este trabalho avaliar a composição visceral, o rendimento de cortes e a qualidade de carne de duas linhagens de frangos tipo caipira alimentados com dietas contendo cana-de-açúcar triturada. Foram utilizados 448 frangos distribuídos, aos 35 dias de idade, em dois blocos casualizados, em esquema fatorial 4x2, sendo quatro níveis de substituição da ração (0; 15; 30 e 45%) por de cana-de-açúcar e duas linhagens (Pesadão e Label Rouge), em duas repetições por bloco de quatorze aves unidade experimental. Em 30 minutos após o abate, o parâmetro a* foi maior para os animais da linhagem Pesadão em relação à linhagem Label Rouge. Observou-se efeito quadrático com o aumento dos níveis cana-de-açúcar sobre o parâmetro L* da carne do peito; e efeito linear sobre o parâmetro b* da pele do peito. Em 24 horas após o abate, observou-se efeito quadrático dos níveis de cana-de-açúcar sobre o parâmetro b* da carne do peito. O aumento dos níveis de cana-de-açúcar reduziu linearmente o peso do coração, fígado, peito, coxa mais sobrecoxa, asa, rendimento de carcaça e peso relativo do coração dos animais. Observou-se efeito quadrático com o aumento dos níveis de cana-de-açúcar sobre o peso relativo da gordura abdominal, sendo que o menor teor de gordura foi observado nos animais que consumiram até 30% de cana-de-açúcar. O uso da cana-de-açúcar como alimento alternativo em até 45% na dieta, possibilita manter a qualidade de carne e reduz o teor de gordura abdominal, porém, diminui o rendimento de carcaça.

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The objective of this study was to assess the microstructural characteristics of goat's milk chocolates formulated with different concentrations of cocoa mass by rheological measurements and microscopy. For rheological characterization, rotational and oscillatory tests were performed, while crystal morphology was observed by means of atomic force microscopy (AFM) and 3D optical profilometer. It was verified that the chocolates presented pseudoplastic and thixotropic behavior. The Herschel-Bulkley model adequately described the flow behavior of the formulations. In the oscillatory tests, it was found that the tangent δ (loss) decreased from 0.33 to 0.17 as a function of the increase in cocoa mass concentration. The creep recovery tests were consistent with the other rheological tests. The analysis of AFM and profilometer indicated that there are different microscopic pores on the surface of the chocolates, and that with the increase in the concentration of cocoa mass, it has a structure with greater interactions.

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The surface properties and foaming of ovalbumin and guar gum aqueous solutions was investigated in the presence of sucrose or sorbitol. All solutions had a broad particle size distribution (395.60 at 1137.50 nm). Higher ovalbumin concentrations had lower equilibrium surface tension and higher absolute values of the zeta potential, regardless the presence of sucrose or sorbitol. Mixtures containing ovalbumin and guar gum resulted in a predominantly elastic character of the air-water interface probably due to the formation of a complex (hydrogen bonding and/or hydrophobic interactions) between ovalbumin and guar gum. Besides, the increase in guar gum concentration enhanced the elasticity of the surface film. Higher concentrations of both polymers were required to provide higher kinetic stability to the system, although the increase in guar gum concentration reduced foam capacity due to the increase in the apparent viscosity. Foams formed in the presence of sucrose or sorbitol showed similar half-lives.

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A doença celíaca é uma doença inflamatória autoimune do intestino delgado, desencadeada pela ingestão de glúten. O desenvolvimento de produtos isentos de glúten que apresentem boas características sensoriais se torna uma grande oportunidade para a indústria alimentícia. Nesse contexto, o objetivo deste trabalho foi desenvolver formulações de bolo de chocolate sem glúten e avaliar o perfil sensorial pelos consumidores. As formulações diferiram na proporção de farinha de arroz e dos diferentes substitutos das farinhas utilizados. Após garantir a segurança microbiológica, o produto foi caracterizado sensorialmente pelo método Check-all-that-apply (CATA) por 102 consumidores. A formulação F2 no teste CATA se assemelhou a F1. Dessa maneira, foi possível perceber que ambas formulações apresentaram características sensoriais desejáveis e podem ser uma boa alternativa para aqueles que desejam ou precisam de uma dieta isenta de glúten.(AU)

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A doença celíaca é uma doença inflamatória autoimune do intestino delgado, desencadeada pela ingestão de glúten. O desenvolvimento de produtos isentos de glúten que apresentem boas características sensoriais se torna uma grande oportunidade para a indústria alimentícia. Nesse contexto, o objetivo deste trabalho foi desenvolver formulações de bolo de chocolate sem glúten e avaliar o perfil sensorial pelos consumidores. As formulações diferiram na proporção de farinha de arroz e dos diferentes substitutos das farinhas utilizados. Após garantir a segurança microbiológica, o produto foi caracterizado sensorialmente pelo método Check-all-that-apply (CATA) por 102 consumidores. A formulação F2 no teste CATA se assemelhou a F1. Dessa maneira, foi possível perceber que ambas formulações apresentaram características sensoriais desejáveis e podem ser uma boa alternativa para aqueles que desejam ou precisam de uma dieta isenta de glúten.

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Colorimetric nanosensors formed of polydiacetylene (PDA), triblock copolymer (L64 or F68), and sodium dodecyl sulfate (SDS), so-called nanoblends, were developed to detect enrofloxacin (ENRO) in aqueous media. The nanosensors show hydrodynamic diameter ranging from 234.2 ±â€¯3.5 to 801.6 ±â€¯17.8 nm for SDS concentrations of 13.0-21.0 mM, respectively. The lowest limit of detection was 0.054 µM, which is five times smaller than the maximum limit allowed by the European Union. The response surfaces showed that both the SDS and ENRO concentrations influenced the colorimetric response (p < 0.05), and kinetic rate of colorimetric transition (RCT). SDS concentration between 11.0 and 14.0 mM in the nanoblend yielded the most sensitive nanosensors for detecting ENRO. When L64 was replaced by F68, the colorimetric response of the nanoblends was similar, but PDA/F68/SDS showed a slower RCT than PDA/L64/SDS. The developed nanosensor is a sensitive and simple device for the fast detection of ENRO.

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