A physicochemical evaluation of ossein-hydroxyapatite within the bovine bone matrix revealed demineralization and making type I collagen available as a result of processing and solubilization by acids

Bovine bone is an animal-origin matrix rich in type I collagen (COL I) and it necessitates prior demineralization and makes COL I available. This study investigated the ossein-hydroxyapatite physicochemical properties evaluation as a result of processing and solubilization by acids and revealed the bone matrix demineralization and making COL I available. The tibia residue from bovine sources was processed, ground, and transformed into bone matrix powder. The bone matrix was solubilized in acetic acid followed by lactic acid. The bone matrix was evaluated as a result of processing and solubilization by acids: ossein and hydroxyapatite percentages by nitrogen and ash content, mineral content, particle size distribution, Fourier-transformation infrared spectroscopy, x-ray diffraction, and scanning electron microscope. For the obtained residual extracts, pH and mineral content were evaluated. The solubilization by acids affected the ossein-hydroxyapatite physicochemical properties, and the bone matrix solubilized by acetic and lactic acid showed the preservation of the ossein alongside the loss of hydroxyapatite. The processing and the solubilization by acids were revealed to be a  alternative to bone matrix demineralization and enabling the accessibility of bone COL I. PRACTICAL APPLICATION: Bovine bone is an abundant type I collagen source, but processing maneuvers and demineralization effect present limitations due to the rigidity of the structural components. Exploring methodologies to process and demineralize will allow type I collagen to be obtained from the bone source, and direct and amplify the potentialities in the chemical and food industries. The research focused on bone sources and collagen availability holds paramount significance, and promotes repurposing agribusiness residues and development of protein-base products.

Enzymatic hydrolysis improves the encapsulation properties of rice bran protein by increasing retention of anthocyanins in microparticles of grape juice

There is a growing demand for the food industry to find appealing matrices that display a clean and sustainable label capable of replacing animal proteins in the encapsulation market for natural pigments. Therefore, this study evaluated the impact of enzymatic hydrolysis by Flavourzyme protease on the encapsulation properties of rice bran proteins, aiming to protect anthocyanins in grape juice microparticles. To achieve this, rice bran protein hydrolysates (RPH) with low (5%, LRPH), medium (10%, MRPH), and high (15%, HRPH) degrees of hydrolysis (DH) were used combined with maltodextrin as carrier agents for the microencapsulation of grape juice by spray drying. The feed solutions contained 1 g of carrier agents (CA)/g of soluble solids from the juice (SS) and protein: a 15% CA ratio. Non-hydrolyzed rice protein was used as a carrier agent to obtain a control sample to evaluate the effect of enzymatic hydrolysis on the microencapsulation of grape juice. Protein modification increased the surface activity of the protein and its ability to migrate to the surface of the microparticles, forming a protective film, as observed by X-ray photoelectron spectroscopy. Using HRPH as a carrier agent combined with maltodextrin improved the internal and total anthocyanin retention, antioxidant capacity measured by DPPH and ABTS+ assays, and powder recovery compared to the control sample, and increased DH reduced particle size and powder stickiness. These particles were more homogeneous, rough, and without cracks. The microencapsulation efficiency was above 70%. All powders exhibited low values of hygroscopicity and degree of caking. Therefore, enzymatic hydrolysis proves to be a promising alternative for improving rice bran protein's encapsulating properties since using RPH as an encapsulating agent conferred greater protection of anthocyanins in microparticles. Moreover, the HRPH sample exhibited the most favorable outcomes overall, indicating its potential for prospective utilization in the market, supported by its elevated Tg.

Microencapsulation of organic coffee husk polyphenols: Effects on release, bioaccessibility, and antioxidant capacity of phenolics in a simulated gastrointestinal tract

Whey protein concentrate (WPC) and maltodextrin were used to microencapsulate polyphenols extract from organic coffee husks by spray drying. The microparticles were characterized and evaluated for their influence on the release, bioaccessibility, and antioxidant capacity of polyphenols in the simulated gastrointestinal tract. WPC as a single encapsulating agent promoted better yield (54.8%) of microparticles. The microparticles showed solubility above 92%, and lower hygroscopicity when encapsulated with maltodextrin alone (7.4%). Smaller diameter (6.78 µm), better encapsulation efficiency (89.1%) and retention of compounds (74.4%) were observed in microparticles with WPC in the composition. Polyphenols were completely released from the microparticles during simulated gastric digestion. The microparticles influenced the bioaccessibility of over 70% of the polyphenols in the intestinal phase. The microparticles showed rapid gastrointestinal release effect but favored the increase of bioaccessibility and preservation of the antioxidant capacity of polyphenols, especially those from the microparticles with WPC compared to the free extract.

Novel Brazilian hop (Humulus lupulus L.) extracts through supercritical CO2 extraction: Enhancing hop processing for greater sustainability

Hop cultivation has been increasing in the past decade in Brazil, demanding a better understanding of how the processing influences the national hop varieties. Despite the hop process being well-established in the producer countries, there is still room for optimization to reduce energy consumption for a more sustainable process. This study's main purpose was to understand the influence of drying and supercritical CO2 extraction on the quality of hop extracts. The hop quality during drying was evaluated regarding color, bitter acids, xanthohumol, total essential oil content, and volatile profile. Supercritical CO2 extraction yields, and bitter acid recovery were assessed by HPLC in a range of different temperatures (40 or 60 °C) and pressure (15, 20, 25, or 30 MPa) conditions. Hop processing was optimized to produce a greater extract quality from a Brazilian hop variety, saving energy and solvent consumption, and consequently, reducing the process footprint. Furthermore, this study established supercritical CO2 extraction conditions for Brazilian hop extract production, offering the national beer industry an alternative to overpriced products.

Rice bran protein increases the retention of anthocyanins by acting as an encapsulating agent in the spray drying of grape juice

Rice bran protein concentrate (RPC), an industrial by-product, may emerge as a green alternative for substituting animal proteins in microencapsulating compounds of interest. This study applied RPC, combined with maltodextrin (MD) as carrier agents, in the spray drying of grape juice, a product rich in these bioactive compounds, seeking to protect anthocyanins from degradation. The effects of carrier agent concentration [C: 0.75, 1.00, and 1.25 g of carrier agents (CA)/g of soluble solids of the juice (SS)] and RPC:CA ratio (P: 0%, as a control sample, 5%, 10%, 15%, and 20%) on anthocyanin retention and powder properties were evaluated. At 1.00 g CA/g SS, the internal and total retentions of anthocyanins improved by 2.4 and 3.2 times, respectively, when the RPC:CA ratio increased from 0% to 20%. The protein also exhibited excellent surface activity on the grape juice and positively influenced the physicochemical properties of the microparticles. There was a reduction in stickiness, degree of caking, and hygroscopicity, in addition to an increased antioxidant capacity when protein was used in combination with MD, especially at 1.00 and 1.25 g CA/g SS. Therefore, this study demonstrated that RPC could enhance the protection of anthocyanins during the spray drying of grape juice.

Performance of rice protein hydrolysates as a stabilizing agent on oil-in-water emulsions

Rice protein isolate (RPI) has been receiving increasing attention from the food industry due to its performance as an emulsifier. However, it is possible to enlarge its field of applications through enzymatic hydrolysis. Therefore, this work aimed to investigate the effects of the controlled enzymatic hydrolysis (degree of hydrolysis DH as 2, 6, and 10%) using Flavourzyme on the physicochemical properties of rice protein and to identify the minimum concentration of these hydrolysates (0.5, 1.0, and 1.5%) to form and stabilize oil/water emulsion. The physicochemical, interfacial tension (IT), and surface characteristics of RPI and their hydrolysates (RPH) were determined. Even at a lower protein concentration (1.0%), protein hydrolysate presented lower IT when compared with RPI at a higher protein concentration (1.5%). The interfacial tension decreased from 17.6 mN/m to 9.9 mN/m when RPI was hydrolyzed. Moreover, enzymatic hydrolysis (DH 6 and 10%) enhanced the protein solubility by almost 20% over a pH range of 3-11. The improved amphiphilic property of RPH, supported by the results of IT and solubility, was confirmed by the higher emulsion stability indicated by the Turbiscan and emulsion stability indexes. Emulsions stabilized by RPH (DH 6% and 10%) at lower protein concentrations (1%) exhibited better physical stability than RPI at higher protein concentrations (1.5%). In this work, we verified the minimum concentration of rice protein hydrolysate required to form and stabilize oil-in-water (O/W) emulsions.

Enzymatic pretreatment in the extraction process of soybean to improve protein and isoflavone recovery and to favor aglycone formation

This research aimed to evaluate the pretreatment of soybean with the carbohydrase multi-enzyme complex "Viscozyme L", during the extraction process; in order to improve the recovery of proteins and isoflavones in soybase, and reduce the loss of these compounds through the okara residue. Three concentrations of enzyme were studied at 50 °C, along with an experiment carried out without enzyme addition (control experiment). The results were also evaluated in relation to standard soybase processing. In comparison to the standard and control processes, the enzymatic pretreatment reduced up to 85% the total amount of okara residue. Due to the action of the multi-enzyme complex, protein and total isoflavone recovery increased from 42% to 83% and from 59% to 93%, respectively. The application of Viscozyme L also favored the conversion of conjugated forms of isoflavone to aglycone in the soybase, representing up to 50% of the total isoflavones. The enzymatic pretreatment of soybean with carbohydrase improved the nutritional quality of the soybase, while at the same time reducing residue generation; showing that the proposed food process can be considered environmentally friendly method.

Modulation of aroma release of instant coffees through microparticles of roasted coffee oil

We report, on the successful addition of spray-dried microparticles containing roasted coffee oil, to soluble coffee (SC) and instant cappuccino (IC), to increase and tailor aroma release. Using PTR-ToF-MS (Proton Transfer Reaction Time-of-Flight Mass Spectrometry), five parameters were defined from time series intensity for each VOC, to compare the performance of different products: total area under the curve (AUC), area under the curve of burst (AUC-burst), maximum signal intensity, final intensity (5 min), and ratio AUC-burst/AUC. Microparticles with higher loads of roasted coffee oil were effective in increasing aroma intensity in SC while, for IC, all loads of microparticles improved aroma intensity. Volatility drove the VOC release in SC, and volatility and polarity for IC. Most compounds reached maximum headspace concentration in < 16 s upon start of reconstitution. These results open new perspectives for the development of instant coffee products and demonstrate their unique aroma release characteristics.

Novel experimental approach to study aroma release upon reconstitution of instant coffee products

This study presents an experimental approach to study the kinetics and fast release of volatile organic compounds (VOCs) upon reconstitution of instant coffee products. A sampling setup coupled to PTR-ToF-MS (Proton Transfer Reaction Time-of-Flight Mass Spectrometry) for the automated and reproducible reconstitution of instant coffee products was developed to monitor the dynamic release of VOCs. A rapid release of aroma compounds was observed in the first seconds upon hot water addition ("aroma burst"), followed by subsequent decrease in headspace (HS) intensities over the course of analysis. Differences in time-intensity release profiles of individual VOCs were correlated to their Henry's Law constant, vapor pressure and water solubility. The setup and approach proposed here have shown to be sensitive and to respond to fast dynamic changes in aroma release. It allows studying VOCs release upon reconstitution and supports the development of novel technologies and formulations for instant products with improved aroma release properties.

Influence of combined hydrolyzed collagen and maltodextrin as carrier agents in spray drying of cocona pulp

Abstract This work aimed to evaluate the effect of carrier agents containing maltodextrin and protein, represented by hydrolyzed collagen on the spray drying process of cocona (Solanum sessiliflorum Dunal), and on the properties of the resulting powders. We used pre-established proportions between the solids of cocona pulp and the carrier agents (P:CA), and among carrier agents themselves, maltodextrin and hydrolyzed collagen, (MD:HC). The process was carried out in a spray dryer at an inlet air temperature of 120 ºC. We prepared twelve feed solutions containing 20% of total solids, with P:CA ratios of 1:3, 1:4, 1:5 and 1:6, and MD:HC ratios of 0:100, 50:50, and 100:0. Solids recovery was obtained for the evaluation of the spray drying process. The cocona pulp powders were analyzed for moisture content, water activity, particle size distribution, mean particle diameter, chemical structure (FTIR) and color. For a P:CA of 1:6, for the sample formulated with hydrolyzed collagen only, solids recovery (96.2%) was much higher than that of the sample with maltodextrin only (39.2%). The chemical structure of cocona powders can be considered a sign of a good encapsulation process. The color of the cocona pulp powder was similar to that of the carrier agents. The formulation with highest content of hydrolyzed collagen improved the recovery of solids, guaranteed the cocona pulp encapsulation, and obtained fruit powders with bioactive properties.

Estabilidade física e química de hidrolisados proteicos de okara microencapsulados por spray drying

Resumo A microencapsulação é um processo indicado para proteger substâncias que são susceptíveis à degradação ou redução da sua funcionalidade por causa de diferentes reações, por exemplo, oxidação, hidrólise, entre outras. O objetivo deste estudo foi avaliar o efeito da microencapsulação, usando como materiais de parede maltodextrina ou amido modificado, sobre a estabilidade de hidrolisados proteicos de okara. A pesquisa analisou a microestrutura, a capacidade antioxidante e a cor das amostras durante a estocagem dos pós por 120 dias a 35 °C. As micrografias obtidas por microscopia eletrônica de varredura indicaram que o processo de microencapsulação favoreceu a integridade física das partículas. A diferença de cor observada entre as amostras encapsuladas e não encapsuladas foi proveniente, provavelmente, da adição de materiais de paredes que contribuíram para a mudança da cor do pó obtido por spray drying. Os resultados indicaram que as microcápsulas obtidas por spray drying usando maltodextrina ou amido modificado mantiveram a cor dos pós e apresentaram boa habilidade em sequestrar o radical livre ABTS e teor de substâncias redutoras do reagente Folin-Ciocalteu durante a estocagem.

Optimizing the potential bioactivity of isoflavones from soybeans via ultrasound pretreatment: Antioxidant potential and NF-κB activation

Soybean consumption has been associated with health benefits. However, the effect of ultrasound (US) soybean pretreatment in terms of potential health benefits has not been investigated so far. Accordingly, the total phenolic content (TPC) and the total aglycone content (TAC) were optimized using the Box-Behnken design. Contrasting samples regarding isoflavones aglycones and TPCs were screened for their antioxidant and anti-inflammatory potentials using RAW 264.7 macrophages. US pretreated soybeans (55°C, 15 min, and 24 W/cm2 ) showed greater TPC and TAC compared to the control and this translated to higher antiradical activity and reduction of nuclear factor kappa B (NF-κB) activation. The concentration of genistein in treated soybeans increased by 95%. Furthermore, US pretreated soybeans rendered phenolic extracts that reduced the NF-κB activation by 86%. Therefore, this contribution demonstrates the beneficial effects of US pretreatment of soybeans, which provides a better feedstock for the functional food industry. PRACTICAL APPLICATIONS: Soybeans can be consumed as such or used as a feedstock to produce soy yogurt, fermented soymilk, tofu, and protein concentrate, among others. The greatest bioavailability of isoflavones compared to other flavonoids has recently been highlighted, and this has been explained by the relatively moderate lipophilicity of isoflavones as aglycones. The present contribution supports the use of US pretreatment of soybeans to obtain a feedstock with improved contents of isoflavones as aglycones. We have confirmed that phenolic extracts obtained from the US pretreated samples showed higher bioactivity as radical scavengers and by reducing the activation of nuclear factor kappa B (NF-κB) in a cell model, which is mediated by oxidative species. The clinical importance of NF-κB activation is derived mainly from its role in inflammatory responses. Therefore, our investigation may have a practical application in the procurement of soybean products and/or ingredients with improved functional properties related to their health benefits.

Ultrasound- and hemicellulase-assisted extraction increase β-glucosidase activity, the content of isoflavone aglycones and antioxidant potential of soymilk

Soymilk is consumed as such or used in the preparation of tofu, fermented soymilk, and soy yogurt, among others. In this study, hemicellulase-assisted extraction (HAE) and ultrasound-assisted extraction (UAE) were used during soymilk manufacturing. The activity of endogenous β-glicosidases was increased 1.3 and 1.5-fold in soymilk produced upon HAE and UAE, respectively. Likewise, the concentration of isoflavones in the aglycone form increased 1.7 and 2.4 times in samples subjected to HAE and UAE, respectively. UAE, but not HAE, rendered an equimolar conversion from conjugated isoflavones to their respective aglycones. In addition, HAE and UAE showed higher antiradical activity towards ABTS radical cation and peroxyl radical, compared to those of the control. The aglycone isoflavones/conjugated isoflavones (aISO/cISO) ratio correlated with the antiradical activity, thus suggesting that the soybean industry may use this new quality index to indicate the antioxidant potential of products. Food formulations containing soymilk with high aISO/cISO ratio may translate to higher oxidative stability of the final product. Likewise, the higher absorption of aglycone isoflavones compared to that of their conjugated counterparts is well recognized. Therefore, high aISO/cISO ratio of soymilk and/or its products may provide a better antioxidant protection under physiological conditions.

Avaliação do potencial antioxidante de proteínas do soro de leite concentradas por ultrafiltração e hidrolisadas por diferentes proteases comerciais

Resumo O objetivo do trabalho foi avaliar as atividades antioxidante e antimicrobiana de hidrolisados proteicos de soro de leite obtidos por diferentes proteases (Alcalase e Flavourzyme) e sua mistura (proporção 50:50). Previamente à hidrólise enzimática, o soro de leite foi concentrado por ultrafiltração com membranas cerâmicas tubulares. A reação enzimática foi realizada de acordo com o método pH-stat, sendo coletadas alíquotas com diferentes graus de hidrólise ( GH), ao longo de cada hidrólise proteica. Os hidrolisados foram analisados quanto a estimativa do teor de peptídeos, atividade antioxidante pelos métodos de captura do radical livre ABTS+ e do radical peroxila (Oxygen radical antioxidant capacity - ORAC), eletroforese e atividade antimicrobiana. Os máximos GH alcançados foram 15%, 52% e 63%, para Flavourzyme, mistura das enzimas e Alcalase, respectivamente. A atividade antioxidante aumentou com o GH. Os hidrolisados proteicos obtidos pela Alcalase apresentaram maiores atividades antioxidantes que os outros hidrolisados. Entretanto, nenhum hidrolisado proteico apresentou atividade antimicrobiana contra as cepas de Salmonella choleraesuis subsp. Enteritidis (ATCC 13076) e Listeria monocytogenes (ATCC 9117).

Soybean ultrasound pre-treatment prior to soaking affects β-glucosidase activity, isoflavone profile and soaking time

Ultrasound may convert conjugated isoflavones into their corresponding aglycones, the best form for absorption in the human body. However, ultrasound may also influence the activity of endogenous β-glucosidase. Therefore, the present work evaluated the effects of soybean ultrasound pre-treatment by applying the Box-Behnken design prior to soaking, a step that is important for industries to prepare certain soy products. Furthermore, a multi-response optimisation is provided. The best conditions for soybean ultrasound pre-treatment were established as temperature, X1 = 55 °C; exposure time, X2 = 5 min and ultrasound intensity, X3 = 19.5 W cm-2. Under these conditions, soybeans with higher contents of aglycones were obtained and β-glucosidase activity was kept as high as possible. A second experiment was conducted and confirmed that ultrasound pre-treatment results in a lower soaking time (2 h) to achieve the highest moisture content, lower hardness as well as increased content of aglycones.

Action of multi-enzyme complex on protein extraction to obtain a protein concentrate from okara

The objective of this study was to optimize the extraction of protein by applying a multi-enzymatic pretreatment to okara, a byproduct from soymilk processing. The multi-enzyme complex Viscozyme, containing a variety of carbohydrases, was used to hydrolyze the okara cell walls and facilitate extraction of proteins. Enzyme-assisted extraction was carried out under different temperatures (37-53 °C), enzyme concentrations (1.5-4%) and pH values (5.5-6.5) according to a central composite rotatable design. After extraction, the protein was concentrated by isoelectric precipitation. The optimal conditions for maximum protein content and recovery in protein concentrate were 53 °C, pH 6.2 and 4% of enzyme concentration. Under these conditions, protein content of 56% (dry weight basis) and a recovery of 28% were obtained, representing an increase of 17 and 86%, respectively, compared to the sample with no enzymatic pretreatment. The multi-enzyme complex Viscozyme hydrolyzed the structural cell wall polysaccharides, improving extraction and obtaining protein concentrate from the okara. An electrophoretic profile of the protein concentrate showed two distinct bands, corresponding to the acidic and basic subunits of the protein glycinin. There were no limiting amino acids in the protein concentrate, which had a greater content of arginine.

The effect of thermal treatment of whole soybean flour on the conversion of isoflavones and inactivation of trypsin inhibitors

The aim of this paper was to evaluate the effect of the thermal treatment of whole soybean flour (WSF) on the conversion of isoflavones and the inactivation of trypsin inhibitors. Soybeans were ground and whole soybean flour was obtained and subjected to heat treatment in an oven for 10, 15 and 20min at 100, 150 and 200°C according to a 3(2) experimental design. The response functions were taken to be the contents of different isoflavone forms and the residual activity of trypsin inhibitors. The thermal treatment in the oven altered the content and profile of the different isoflavones forms. At 200°C for 20min, there was a higher conversion of malonylglycosides to acetylglycosides, β-glycosides and aglycones and a significant reduction in the activity of trypsin inhibitors. Mathematical models were established to estimate the process parameters in obtaining the WSF with isoflavone conversions and reductions in trypsin inhibitor activity.