Ferrous sulfate microparticles obtained by spray chilling: characterization, stability and in vitro digestion simulation

The use of microencapsulated ferrous-sulfate is among the various options recommended for food fortification, as the protective wall material surrounding the compound can preserve it from undesirable alterations and also protect the food. Microencapsulated iron can be produced using different wall materials and encapsulation methods. Thus, a microparticle was developed through spray chilling, containing ferrous sulfate (FS), as active compound, and a fat mixture as the coating material. The resulting samples analyzed to determine encapsulation efficiency, particle size distribution, and morphology. Furthermore, the oxidative stability and bioaccessibility of FS microparticles were investigated by simulating in vitro digestion. The findings indicated that the encapsulation technique effectively retained FS, resulting in microparticles physically stable at room temperature with typical morphology. The encapsulation efficiency revealed that lower concentrations of FS led to reduced superficial iron content. However, the oxidative stability demonstrated that the presence of iron in the microparticles accelerated the lipid oxidation process. The in vitro digestion test demonstrated that the microparticles with lower iron content exhibited a higher percentage of bioaccessibility, even when compared to non-encapsulated FS. Additionally, the coating material successfully released FS during the simulation of gastrointestinal digestion, resulting in a bioaccessibility of 7.98%.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05820-1.

Encapsulation of pomegranate polyphenols by ionic gelation: Strategies for improved retention and controlled release

This study aimed at producing pectin hydrogel beads by ionic gelation proce to carry pomegranate extract (PE) evaluating approaches to increase its retention and protect the polyphenols from environmental conditions that interfere in the stability and color of these compounds, such as the pH of the medium. Several strategies were tested to reduce the mass transfer and consequently increase its retention. The insertion of a filler (gelatinized starch), the employment of different concentrations from the external environment, the adsorption using blank pectin-starch beads, and the electrostatic coating using chitosan were performed. The release of entrapped compounds over time was employed to evaluate the release pattern of PE in water media. Diffusion coefficients calculated from these experiments were then used to estimate the PE release behavior. The encapsulation efficiency (EE) was significantly improved (42 % to 101 %) when equalizing the concentration of the external medium with that from the beads formulation. Furthermore, the increase in the PE concentration was proportional to the rise in the mechanical strength (MS) of the beads which indicates a modification of internal structure due to the presence of polyphenols. The adsorption was efficient in entrapping the active compound, and despite the high PE content observed for all beads (average value of 2960.26 mg of gallic acid equivalent/100 g sample), they had the lowest diffusion coefficient from the release in water media. Finally, the coating was able to reduce the release rate in most of the tests (DAB uncoated = 0.5 DAB coated), however, during the electrostatic deposition a loss of about 32 % of the phenolic compounds in the chitosan solution was observed which led to a reduced EE. Despite the obtention of retarded release, coating studies need to be improved. Some adjustments in the execution of this technique are necessary so that the losses are reduced and the process becomes viable for the use of beads in food.

Atomization of Cocoa Honey Using Whey Protein Isolate to Produce a Dry Formulation with Improved Shelf Life for Industrial Application

Cocoa honey, a by-product obtained during the processing of cocoa, is a juice rich in pectin, organic acids, minerals and phenolic compounds with antioxidant properties. Fresh cocoa honey is quickly fermented due to its high content of reducing sugars, such as fructose and glucose, which limits its shelf life. Currently, cocoa honey is only commercialized in frozen form, as logistical challenges prevent the wide distribution or export of this by-product for applications in the market of sweets, jellies, beverages, confectionery, and nutraceutical foods among others. Spray-drying technology is a viable prospect for the large-scale stabilization of products such as cocoa honey, with less heat exposure compared to other conventional drying methods. This work aimed to evaluate the efficacy of drying adjuvants for a rapid removal of the water present in cocoa honey via atomization, since this process minimizes the effects of glass transition temperature (Tg) related to materials with high sugar contents. Physical parameters such as the moisture content, hygroscopicity, particle size, and yield of the products obtained were determined. Cocoa honey presented 85.3 ± 0.20 g/100 g of moisture. The formulations successfully decreased moisture content, which was lower than 11.72 ± 0.08 g/100 g in the formulations. Water activity ranged between 0.1464 ± 0.0043 and 0.1562 ± 0.029, with no significant difference between the formulations. The hygroscopicity of cocoa honey powders ranged from 29.29 to 29.87 g of water/100 g of cocoa honey. The combination of 20% maltodextrin and 1% whey protein isolate (WPI) led to the best yield, resulting in a free-flowing powder as the final product. On the other hand, the formulation composed of maltodextrin and whey protein isolate in the ratio of 29:1, respectively, led to the most stable product, with less loss of phenolic compounds during the drying process (6.04%). Regarding particle diameter, 90% of the accumulated distribution did not exceed 57 μm. The greatest dispersion of particles occurs in the Ma20W10 formulation with a span of 2.72, inferring greater variation in size between small (7.01 ± 0.06 μm), medium (18.25 ± 0.37 μm), and large (56.65 ± 1.17 μm) particles. The use of whey protein isolate as an adjuvant proved to be an efficient drying process in the production of cocoa honey powder, and was also advantageous for enriching the nutritional content of the final product due to its protein origin. Furthermore, the combination of spray-drying technology and the use of whey protein isolate as adjuvant led to a free-flowing cocoa honey powder with an adequate particle size and benefits in terms of shelf-life extension, providing new opportunities for the commercialization of cocoa honey as an ingredient for the food industry, with benefits for the circular economy.

Microencapsulation of Limosilactobacillus reuteri (DSM 23878) for application in infant formula: Heat resistance and bacterial viability during long-time storage

This study aimed to evaluate the survival capacity of the probiotic culture Limosilactobacillus reuteri (DSM 23878) to microencapsulation by spray drying, and its potential as component of an infant formula. Preliminary tests were performed between skim milk (SM) and infant formula (IF) as wall material and two inlet temperatures, evaluating the encapsulation efficiency, moisture content, water activity and stability, to choose the drying parameters. After drying in optimized conditions, the powder of microencapsulated L. reuteri was characterized and the viability after dilution in an infant formula at 70 °C was determined. In addition, the survival rate throughout 360 days of storage was assessed. As results, encapsulation efficiency was superior to 90 % in both wall materials. However, the use of IF as for microencapsulation produced microparticles with lower water activity (Aw) and moisture, as compared with the SM. Final microparticles produced with IF as wall material presented values of Aw, moisture content, and particle diameter averaged 0.11 ± 0.02, 2.10 ± 0.35 % and 10.30 ± 0.12 μm, respectively. The viability of microencapsulated L.reuteri decreased 1 Log CFU/mL after dilution at 70 °C and the powder maintained a survivor of 73.5 % after 365 days of storage at 4 °C. Thus, the microencapsulation by spray drying under the conditions of this study proved to be an effective technique to protect the probiotic L. reuteri for application in infant formulas, obtaining an adequate number of viable cells after reconstitution at 70 °C and during long time the storage.

Microparticles loaded with fish oil: stability studies, food application and sensory evaluation

AIM

Evaluate the stability of microparticles loaded with fish oil produced by spray drying, spray chilling and by the combination of these techniques (double-shell) and use the microparticles for food application.

METHODS

Samples were stored for 180 days at 6 °C and 24 °C (75% RH). Performed investigations included encapsulation efficiency, moisture content, aw, size (laser scattering), colour (L*, a*, b*), polyunsaturated fatty acids (PUFAs) (GC), thermal behaviour (DSC) and crystalline structure (XRD).

RESULTS

Double-shell microparticles containing 26 wt% core material, 22.74 ± 0.02 µm (D0.5) and 2.05 ± 0.03 span index, 1.262 ± 0.026 wt% moisture content and 0.240 ± 0.001 of aw had PUFAs retention higher than 90 wt% during storage at 6 °C without changes in crystalline structure (β'-type crystals) and melting temperature (54 °C). The sensory evaluation suggested low fish oil release in oral phase digestion.

CONCLUSIONS

Double-shell microparticles were effective to protect and deliver PUFAs.

Umami Ingredient: Flavor enhancer from shiitake (Lentinula edodes) byproducts

An alternative use of shiitake stipes, usually treated as waste, was proposed for the production of a powder ingredient, rich in umami compounds, aiming its application in food. The extraction of umami compounds was optimized through the Response Surface Methodology (RSM), in order to obtain an extract with high umami taste intensity. From the optimized condition, a comparative analysis of shiitake stipes dehydration method was performed. Stipes were dehydrated by hot air drying (HD) and freeze drying (FD), submitted to extraction and the umami compounds in the extracts were compared. The comparative analysis showed that the 5' - nucleotides are more sensitive to prolonged heating, while the release of free amino acids (FAA) was favored by hot air drying. The HD samples extract showed higher Equivalent Umami Concentration (EUC). The spray drying of the HD samples extract allowed the production of a newly powder ingredient rich in umami compounds (Umami Ingredient) that can be applied in diverse food matrices. Due to the presence of umami compounds, Umami Ingredient can be a potential alternative to help in the process of sodium reduction by enhancing food flavor.

Methods of incorporation of D-limonene microparticles in edible films

No presente trabalho, D-limoneno foi microencapsulado por gelificação iônica utilizando alginato e íons cálcio e foi aplicado na formulação de filmes comestíveis biodegradáveis de gelatina e quitosana. Foram avaliados três métodos de incorporação das micropartículas na solução filmogênica: agitação magnética, agitação de alta velocidade (Ultra-turrax) e sonicação. A morfologia das micropartículas e dos filmes foram avaliados por microscopia óptica e microscopia eletrônica de varredura (MEV). Além disso, nas micropartículas determinou-se a eficiência de encapsulação (EE) e o diâmetro médio e nos filmes as propriedades mecânicas e a permeabilidade ao vapor de água (PVA). As micropartículas de D-limoneno apresentaram formato esférico, diâmetro médio de 134,6 ?m e EE de 83,95%. A incorporação de micropartículas elevou a resistência à tração, o módulo de Young e a PVA e reduziu a elongação na ruptura dos filmes. Porém, considerando os métodos de incorporação estudados, não houve diferença significativa, sugerindo que um simples método como a agitação magnética foi suficiente para dispersar as micropartículas na solução filmogênica.

Performance of oil-in-water emulsions stabilized by different types of surface-active components

The emulsion stability depends on the physicochemical properties of the dispersed phase and their interaction with the continuous phase. Surface-active compounds (SAC) are added in emulsions to reduce the interfacial tension (IT) between these phases and keep the oil droplets stabilized. Moreover, small amounts of SAC can occupy intermolecular voids in the dried matrix, reducing the oxidation. However, the formulation must reflect a trade-off between protection and emulsion stabilization. Therefore, this work aimed to identify the minimum concentration of SAC (modified starch-MS, gelatin-GE, and whey protein isolate-WPI) ranging from 0.48 to 6 % (w/w) to form and stabilize droplets of an unsaturated triglyceride (fish oil-FO) or a volatile oil (orange essential oil-OEO). GE did not change the IT (6.7 mN/m) and stabilized the emulsions only through an increase of the viscosity (∼42 mPas for FO-emulsions and ∼97 mPas for OEO-emulsions), presenting high droplet size (∼10 μm) and low surface charge (∼1.5 mV). WPI reduced the IT to a limit value (4.5 mN/m at 1.2 % w/w for OEO and 5.3 mN/m at 2.4 % w/w for FO), whereas MS reduce constantly the IT with the increase of the concentration for both oils (∼4.2 mN/m at 6 % w/w). Both WPI and MS-emulsions presented similar droplet size (∼2.0 μm), but WPI presented higher surface charge of WPI-emulsions (-45 mV) than MS-emulsions (-30 mV). This study allowed to gain a consistent understanding of structure-property relationships on the use of SAC in emulsions.

Microencapsulation of green tea polyphenols by ionic gelation and spray chilling methods

The consumption of teas has been increasing with the dissemination of information regarding the health benefits of its constituents. Obtaining food products with healthier profiles is already a reality for industry with the increasing development of new functional ingredients, including the use of tea and its derivatives (extracts). This work aimed to evaluate the encapsulation of green tea extract powder in lipid microparticles (LMP) by the spray chilling method and in ionic gelation microparticles (IGMP) by the ionic gelation method to obtain polyphenol-rich water insoluble components. Microparticles were adequately obtained in both methods, with typical physical characteristics consistent with the results in literature results, 83.5 ± 2.8% encapsulation efficiency for LMP and 72.6 ± 0.4% for IGMP, and antioxidant activity (IC50 μg/mL) of 33,169.4 ± 123.8 (IGMP) and 2099.7 ± 35.3 (LMP). The microparticles samples were considered suitable as ingredients for add polyphenols in foods.

Incorporation of microencapsulated hydrophilic and lipophilic nutrients into foods by using ultrasound as a pre-treatment for drying: A prospective study

The present work proposes using the ultrasound technology to incorporate microencapsulated nutrients during pre-treatments for drying of food products. Both hydrophilic and lipophilic nutrients were evaluated: incorporation of microcapsules of iron (obtained by spray drying using maltodextrin as wall material) and carotenoids (obtained by hot emulsification and solidification using hydrogenated palm oil as wall material). The ultrasound pre-treatment was applied in water and ethanol, where the microcapsules were dispersed, and food samples were immersed. Pumpkin and apple were selected as suitable food material to perform the iron and carotenoid incorporation, respectively. Ultrasound allowed more homogeneous iron incorporation in pumpkin. The iron content increased more than 1000% in pre-treated samples compared to control. In the same manner, carotenoid content increased in about 430% when ultrasound was applied. After drying, the carotenoid content decreased by 65% in control samples. However, better carotenoid retention was obtained after drying in ultrasound processed samples. The results show that pre-treatment with ultrasound can be used to incorporate nutrients into the food matrix, increasing not only the incorporated quantity but also promoting their preservation. Nevertheless, future studies must be performed to determine the nutrient bioavailability and bioaccessibility.

The influence of the storage temperature on the stability of lipid microparticles containing ginger oleoresin

Ginger oleoresin (GO) can be encapsulated within a protective lipid matrix in order to facilitate handling, provide protection against the external environment or promote the stability of GO compounds. The aim of this study was to verify the ability of solid lipid microparticles (SLMs) containing GO (10-20% w/w) to maintain or improve the stability of ginger compounds, by monitoring SLMs' characteristics during storage at different temperatures (25 and 40 °C). The lipids matrix of SLMs were composed by stearic acid (90, 80, 75, 65% w/w) and oleic acid (15% w/w), The crystalline structure of the particles after 84 days of storage did not present any polymorphic alterations, while presenting spherical form upon scanning by electron microscopy. SLMs containing oleic acid showed degradation of 6-gingerol when stored at 40 °C. Major volatile compounds had better stability in particles containing oleic acid. Kinetics of volatiles release resulted in a diffusion mechanism. SLMs showed better stability of GO compounds during storage at 25 °C than un-encapsulated GO and could, therefore, improve its distribution in foods due to its conversion to powder.

Composição lipídica, características físicas e sensoriais de recheios de morango em biscoitos

Resumo Recheios de biscoito de cinco marcas comerciais brasileiras foram avaliados quanto a teor de lipídios, composição em ácidos graxos, atividade de água, diâmetro médio e distribuição do tamanho de partícula, aspecto morfológico, textura (firmeza e adesividade), além de avaliação sensorial, por teste de aceitação, quanto aos atributos: sabor global, sabor de morango, cor, arenosidade, cerosidade e firmeza. Os cinco recheios comerciais avaliados apresentam valores de atividade de água de 0,47 a 0,50. Apenas um diferiu quanto ao tamanho de partícula, apresentando o maior diâmetro médio e a menor aceitação da arenosidade. Quanto à firmeza, houve maior variação entre as marcas comerciais (37,41 a 124,04 gf), assim como na composição em ácidos graxos, indicando diferentes fontes lipídicas nas gorduras destinadas aos recheios. O teor médio de lipídios encontrado, 27,5%, está próximo ao da literatura, de 30%; porém, de acordo com a composição em ácidos graxos, o valor médio de ácidos graxos trans encontrado indica que a indústria pode estar realmente reduzindo os teores desses ácidos graxos, não obstante os valores de ácidos graxos saturados ainda mostrarem-se altos.

Controlled Release of Protein from Hydrocolloid Gel Microbeads Before and After Drying

Casein entrapped within gel microbeads using alginate, amidated LM pectin, gellan gum and a system containing a mixture of these polysaccharides (pectin:gellan:alginate, 1/3: 1/3: 1/3), were obtained by ionic gelation in a high-pressure capillary apparatus. Hydrogenated vegetable fat was also added to produce the gel microbeads and protein release in all the systems was measured, including from freeze-dried capsules containing protein and fat. Encapsulation efficiency, capsule size and morphology were evaluated as well as the protein release profile. Encapsulation efficiencies from 83.7 to 90.7% were obtained for the protein capsules and from 71.8 to 95.4% for those containing protein and fat. Greater release was observed from gel microbeads without fat where alginate presented the greatest diffusion (100%) and the system with a mixture of polyssacharides, the best barrier, with protein retention of 90% after 240 min in solution. The fat containing gel microbeads presented good percent retentions and both the gel microbeads and the dry microbeads showed similar percentages for release. The majority of the systems studied showed a burst effect on release. Gel microbeads size distribution was similar, both with and without fat, and independent of the matrix material, the mean size being 150microm. The morphological observations showed that the gel microbeads were spheroidal with a homogenous distribution of fat droplets in the microcapsules. Agglomeration occurred on drying but many particles maintained a partially spheroidal form, with a configuration of solid material.

Composição centesimal e valor protéico de levedura residual da fermentação etanólica e de seus derivados

Este trabalho teve por objetivo promover a autólise e o fracionamento da levedura (Saccharomyces sp.) para produção de autolisado e extrato, bem como para produção de concentrado protéico fosforilado, a partir da levedura residual das destilarias de álcool etílico. Foram estudados a composição centesimal, o perfil de aminoácidos essenciais e o valor protéico dos três derivados comparativamente à levedura íntegra não processada. Proteína e carboidrato (fibra alimentar) foram os principais componentes da levedura íntegra e do autolisado. No extrato e no concentrado protéico predominaram proteína e minerais (cinzas). O autolisado e a levedura íntegra apresentaram os melhores índices de aminoácidos essenciais, seguidos pelo concentrado protéico e pelo extrato. A digestibilidade da proteína variou de 68% para a levedura íntegra a 91% para o extrato. Os índices de quociente de utilização líquida da proteína variaram de 2,1 para a levedura íntegra a 4,3 para a caseína (referência). Não houve diferença estatística no quociente de utilização líquida da proteína entre o autolisado (4,1), o extrato (3,9) e o concentrado protéico (4,2). O concentrado protéico promoveu o maior crescimento no período (21 dias), seguido do extrato e o autolisado. As células íntegras apresentaram a menor capacidade para promover crescimento em rato.