Electrospun nanofibers based on zein and red onion bulb extract (Allium cepa, L.): Volatile compounds, hydrophilicity, and antioxidant activity.

Onion is rich in bioactive and volatile compounds with antioxidant activity. However, the pungent odor of volatile compounds (VOCs) released restricts its use. The encapsulation of red onion extract by electrospinning is an alternative to mask this odor and protect its bioactive compounds. The main objective of this study was to encapsulate red onion bulb extract (ROE) in different concentrations into zein nanofibers by electrospinning and evaluate their thermal, antioxidant, and hydrophilicity properties. The major VOC in ROE was 3(2H)-furanone, 2-hexyl-5-methyl. Incorporating ROE into the polymeric solutions increased electrical conductivity and decreased apparent viscosity, rendering nanofibers with a lower average diameter. The loading capacity of ROE on fibers was high, reaching 91.5% (10% ROE). The morphology of the nanofibers was random and continuous; however, it showed beads at the highest ROE concentration (40%). The addition of ROE to the nanofibers increased their hydrophilicity. The nanofibers' antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and hydroxyl radicals ranged from 32.5% to 57.3%. The electrospun nanofibers have the potential to protect and mask VOCs. In addition, they offer a sustainable alternative to the synthetic antioxidants commonly employed in the food and packaging industry due to their antioxidant activities.

Natural fermentation of potato (Solanum tuberosum L.) starch: Effect of cultivar, amylose content, and drying method on expansion, chemical and morphological properties.

Natural fermentation with sun-drying is a modification that promotes the expansion capacity of starch, and its effects on potato starch have not been reported so far. The aim of this study was to evaluate the effects of the amylose content of potato (Solanum tuberosum L.) starches and natural fermentation followed by oven or sun drying on its properties. Cassava starch was also used a control. Native and fermented starches were evaluated based on their chemical composition, amylose, carboxyl and carbonyl content as well as their thermal, pasty, and morphological properties. The fermentation water was evaluated by pH and titratable acidity to control the process. Puffed balls were prepared to evaluate expandability, mass loss, porosity and texture. The fermentation intensity was greater for potato and cassava starch with low-amylose content than for potato starch with higher amylose content. In addition, the acidity of the fermentation water increased faster with cassava starch than with potato starches. The fermented potato starches with the highest amylose content had low acidity and low expansion capacity compared to the fermented potato and cassava starches with low-amylose content. Fermentation and sun-drying of low-amylose potato and cassava starches increased the expansion and reduced the hardness of the puffed balls.

Absorbent bioactive aerogels based on germinated wheat starch and grape skin extract.

This study aimed to produce water-absorbent bioactive aerogels using biodegradable raw materials, wheat starch and poly ethylene oxide (PEO), and derived from agro-industrial residues (grape skin) obtained in the wine industry. The aerogels were produced using germinated wheat starch (GWS), with and without PEO, and incorporating grape skin extract (GSE) at concentrations of 5 and 10 % (w/w). The GSE was evaluated for total and individual phenolic compounds, anthocyanins, and antioxidant activity. The starch aerogels were characterized for morphology, density, porosity, functional groups by FT-IR, relative crystallinity and diffraction pattern, water absorption capacity, antioxidant activity, and in vitro release profile of phenolic compounds in food simulant medium. The total phenolic compounds in GSE was 226.25 ± 0.01 mg equivalent of gallic acid/g GSE. The aerogels showed low density and high porosity. All aerogels demonstrated high water absorption capacity (581.4 to 997.5 %). The antioxidant activity of the aerogels increased with increasing GSE concentration and the addition of PEO. The aerogels could release GSE gradually for up to 120 days in the hydrophilic simulant medium and 240 h for the hydrophobic medium. Starch-based aerogels with GSE showed potential to be applied as exudate absorbers with antioxidant activity to develop active food packaging.

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

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

Curcumin encapsulation in capsules and fibers of potato starch by electrospraying and electrospinning: Thermal resistance and antioxidant activity.

The aim of this work was to encapsulate curcumin at different concentrations in capsules and fibers of native potato starch by electrospraying and electrospinning. The best conditions for the production of capsules and fibers were obtained by varying the polymer concentration and resting time of the polymer solution. The best conditions were used for the encapsulation of curcumin. The curcumin-loaded capsules and fibers had an average diameter of 1373 nm to 1787 nm and 108 nm to 142 nm, respectively, and had a high curcumin loading capacity with values ranging from 79.01 % to 97.09 %. Curcumin encapsulated in starch capsules and fibers showed higher thermal stability at 180 °C for 2 h compared to unencapsulated curcumin. The antioxidant activity of starch fibers containing 1 % of curcumin had the greatest ability to inhibit the ABTS radical (45 % inhibition). These materials are promising for use in food or active packaging.

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

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

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.

Dual modification of potato starch: Effects of heat-moisture and high pressure treatments on starch structure and functionalities.

This study investigated the association of heat moisture treatment (HMT) with high hydrostatic pressure (HHP) and evaluated its effects on the thermal, pasting, swelling power, solubility, morphology, and crystallinity characteristics, as well as in vitro digestibility of potato starch. The single and dual modifications significantly altered the pasting properties of potato starch except for HHP. When HHP was applied to HMT starches, the peak viscosities, setback, and final viscosities were greatly increased compared to those of the samples processed with HMT alone. Dual modification increased the transition temperatures, swelling power, and altered the relative crystallinity. The modified starch exhibited a slower rate of glucose release which decreased proportionally with increasing moisture in the HMT. Dual modification showed a remarkable ability to modify starches with different characteristics and can be used as an alternative in the elaboration of low glycaemic index foods.

Development of antimicrobial and antioxidant electrospun soluble potato starch nanofibers loaded with carvacrol.

In this study, a method was developed to encapsulated carvacrol in nanofibers from soluble potato starch. The carvacrol was added in starch solutions at various concentrations (0, 20, 30 and 40% v/v) and electrospun into fibers. The morphology, size distribution, thermal stability, FT-IR spectra, relative crystallinity (RC) and antioxidant of the electrospun fibers were analyzed. For mechanical properties and antimicrobial activities evaluation electrospun nonwovens were obtain. The carvacrol-loaded nanofibers showed homogeneous morphology and average diameters ranging from 73 to 95 nm. The carvacrol encapsulated in the nanofibers had greater thermal stability than the free carvacrol. FT-IR analysis showed interactions between starch and carvacrol. The RC of the nanofibers was approximately 40%. The electrospun nonwovens mechanical properties did not present significant differences (p < 0.05). The 40% carvacrol-loaded nanofibers exhibited higher antioxidant activity with 83.1% of inhibition. The electrospun nonwoven loaded with 30% carvacrol resulted in 89.0% reduction of Listeria monocytogenes, 68.0% for Salmonella Typhimurium, 62.0% for Escherichia coli and 49.0% for Staphylococcus aureus. These electrospun nonwovens sustained antimicrobial activity for at least 30 days against S. aureus. The starch nanofibers are promising materials for application as a vehicle for carvacrol release in antimicrobial and antioxidant food packages.

Nano-scale polysaccharide materials in food and agricultural applications.

Potential applications of nanotechnology in food and agriculture include: (1) the encapsulation of functional compounds; (2) production of reinforcing materials; (3) delivery of nutraceuticals in foods; (4) food safety, for detection and control of chemical and microbiological risks; (5) active and intelligent food packaging; (6) incorporation of protective substances of seeds; (7) addition of nutrients in the soil; (8) use of controlled release pesticides. Natural polysaccharides and their derivatives are widely used in the production of nano-scale materials. This chapter examines, the use of polysaccharides, such as starch, cellulose, lignin, pectin, gums, and cyclodextrins for the production of nano-scale materials, including nanocrystals, nanoemulsions, nanocomplexes, nanocapsules, and nanofibers.

Characteristics of starch from different bean genotypes and its effect on biodegradable films.

BACKGROUND: Starches from four common bean genotypes were characterized and used in the production of biodegradable films. Starches were characterized by their swelling power, solubility, amylose content, granule morphology, relative crystallinity, thermal and pasting properties, and susceptibility to α-amylase hydrolysis. Films were characterized according to their morphology, mechanical and water vapor barrier properties, whiteness and opacity. RESULT: Depending on the common bean genotype, a great variation on starch properties was found, which, in turn, clearly impacted on the characteristics of the starch-based films. Starches from BRS Pitanga and BRS Pérola genotypes exhibited the highest amylose content and the lowest swelling capabilities. Bean starch from the IPR Uirapuru genotype presented granules with an irregular surface and shape. Starches from IPR Uirapuru and BRS Estilo genotypes provided well-structured biodegradable films, without the occurrence of fissures or cracks. Moreover, starch films containing starch from BRS Estilo genotype exhibited the highest flexibility, permeability and solubility. CONCLUSION: The morphological, mechanical and water vapor barrier properties of films elaborated with common bean starch vary greatly as a function of the bean genotype used for starch production. © 2018 Society of Chemical Industry.

Production, Characterization, and Stability of Orange or Eucalyptus Essential Oil/ß-Cyclodextrin Inclusion Complex.

The aim of this study was to produce and characterize inclusion complexes (IC) between ß-cyclodextrin (ß-CD) and orange essential oil (OEO) or eucalyptus essential oil (EEO), and to compare these with their pure compounds and physical mixtures. The samples were evaluated by chemical composition, morphology, thermal stability, and volatile compounds by static headspace-gas chromatography (SH-GC). Comparing the free essential oil and physical mixture with the inclusion complex, of both essential oils (OEO and EEO), it was observed differences occurred in the chemical composition, thermal stability, and morphology. These differences show that there was the formation of the inclusion complex and demonstrate the necessity of the precipitation method used to guarantee the interaction between ß-CD and essential oils. The slow loss of the volatile compounds from both essential oils, when complexed with ß-CD, showed a higher stability when compared with their physical mixtures and free essential oils. Therefore, the results showed that the chemical composition, molecular size, and structure of the essential oils influence the characteristics of the inclusion complexes. The application of the ß-CD in the formation of inclusion complexes with essential oils can expand the potential applications in foods.

Phosphate Fertilizer and Growing Environment Change the Phytochemicals, Oil Quality, and Nutritional Composition of Roundup Ready Genetically Modified and Conventional Soybean.

Phosphorus (P) intake, genotype, and growth environment in soybean cultivation can affect the composition of the soybean. This experiment was conducted in two locations (microregions I and II) using a randomized complete block design, including conventional soybean (BRS Sambaíba) and genetically modified (GM) [Msoy 9144 Roundup Ready (RR)] cultivars and varying doses of phosphorus fertilizer (0, 60, 120, and 240 kg/ha P2O5). Soybeans were evaluated for chemical composition, total phenols, phytic acid content, individual isoflavone content, antioxidant activity, oil quality, fatty acid profile, total carotenoid content, and individual tocopherol contents. Multivariate analysis facilitated reduction in the number of variables with respect to soybean genotype (conventional BRS Sambaíba and GM Msoy 9144 RR), dose of P2O5 fertilizer, and place of cultivation (microregion I and II). BRS Sambaíba had higher concentrations of ß-glucosides, malonylglucosides, glycitein, and genistein than Msoy 9144 RR, which showed a higher concentration of daidzein. The highest concentrations of isoflavones and fatty acids were observed in soybeans treated with 120 and 240 kg/ha P2O5, regardless of the location and cultivar.

Microstructural characteristics and gastro-small intestinal digestion in vitro of potato starch: Effects of refrigerated storage and reheating in microwave.

The objective of our study was to evaluate paste clarity, retrogradation (syneresis %), thermal characteristics and kinetics of glucose release during in vitro gastro-small intestinal digestion of freshly cooked and refrigerated potato starch. Freshly cooked starch pastes had a paste clarity of 71%, which decreased to 35.4% whereas syneresis (%) increased after 7days of refrigerated storage. The X-ray and thermal characteristics of native, retrograded and microwave reheated starch samples differed significantly from each other. For the freshly cooked starch pastes, ∼88% starch hydrolysis was observed at the end (150min) of digestion under simulated gastro-small intestinal conditions that decreased to ∼70% for the 7day stored pastes. The hydrolysis (%) of refrigerated pastes increased to 86% and 92% after one and two cycles of microwave reheating, respectively. These results contribute to the understanding of starch retrogradation in relation to starch digestion.

Study of heat-moisture treatment of potato starch granules by chemical surface gelatinization.

BACKGROUND: Native potato starch was subjected to heat-moisture treatment (HMT) at 12%, 15%, 18%, 21%, and 24% of moisture content at 110 °C for 1 h, and the effects on morphology, structure, and thermal and physicochemical properties were investigated. To reveal the internal structure, 30% and 50% of the granular surface were removed by chemical surface gelatinization in concentrated LiCl solution. RESULTS: At moisture contents of 12% and 15%, HTM reduced the gelatinization temperatures and relative crystallinity of the starches, while at moisture contents of 21% and 24 % both increased. The alterations on morphology, X-ray pattern, physicochemical properties, and increase of amylose content were more intense with the increase of moisture content of HMT. CONCLUSION: The removal of granular layers showed that the changes promoted by HMT occur throughout the whole granule and were pronounced at the core or peripheral region, depending of the moisture content applied during HMT. © 2016 Society of Chemical Industry.

Acetylation of barnyardgrass starch with acetic anhydride under iodine catalysis.

Barnyardgrass (Echinochloa crus-galli) is an invasive plant that is difficult to control and is found in abundance as part of the waste of the paddy industry. In this study, barnyardgrass starch was extracted and studied to obtain a novel starch with potential food and non-food applications. We report some of the physicochemical, functional and morphological properties as well as the effect of modifying this starch with acetic anhydride by catalysis with 1, 5 or 10mM of iodine. The extent of the introduction of acetyl groups increased with increasing iodine levels as catalyst. The shape of the granules remained unaltered, but there were low levels of surface corrosion and the overall relative crystallinity decreased. The pasting temperature, enthalpy and other gelatinisation temperatures were reduced by the modification. There was an increase in the viscosity of the pastes, except for the peak viscosity, which was strongly reduced in 10mM iodine.

Functional, thermal and rheological properties of oat ß-glucan modified by acetylation.

Fibers of ß-glucan have been added to foods for their thickening properties, their ability to form gel at low concentrations, but mainly for their appeal in health promotion. Current analysis evaluates the influence of acetylation (4% and 6% acetic anhydride for 10 and 20 min) on the functional, thermal, morphological and rheological properties of the concentrate containing 31% of oat ß-glucan. The degree of substitution of the acetylated ß-glucans ranged from 0.03 to 0.12, suitable for use in foods. Acetylation increased the heterogeneity of molecule degradation and promoted a more compacted hole-less microstructure. Functional properties such as the swelling power and bile acid binding capacity were increased by acetylation. The ß-glucan gel showed a reduction in hardness and adhesiveness, which was confirmed by its rheological behavior similar to liquid. The above information is relevant to establish the industrial application of acetylated ß-glucan.

Ozone oxidation of cassava starch in aqueous solution at different pH.

Ozone is a more powerful oxidant than common oxidising agents, such as sodium hypochlorite and hydrogen peroxide. It is considered as a safer starch modification method for both consumers and the environment. However, few studies have investigated the changes in starch properties associated with ozone treatment, particularly when applied in aqueous solution. This work aimed to evaluate the carbonyl and carboxyl contents, the X-ray diffraction patterns, the spectrum profiles of Fourier transform infrared spectroscopy, the pasting properties and the surface morphology of ozone-oxidised cassava starch during 60 min under different pH (3.5, 6.5 and 9.5) at 25°C. The pH 6.5 and 9.5 seemed to favour the cross-linking between the depolymerised starch molecules during ozonation. The pH 3.5 was more effective in reducing the peak viscosity, breakdown, setback and final viscosity of cassava starch during ozonation in aqueous solution. No differences in the granule surface morphology were observed in the ozone-treated cassava starches compared to native starch.

Lipid profiles of rats fed with diets supplemented with vitamins niacin and pyridoxine

Hypercholesterolemia is a major risk factor for cardiovascular disease. Supplements containing the vitamins niacin (B3) and pyridoxine (B6) can promote the reduction of total cholesterol and an increase in HDL cholesterol. In this study, the effects of diets supplemented with niacin (B3) and pyridoxine (B6) on the hepatic and serum lipid profiles of Wistar rats were assessed. The diets were prepared with combinations of three concentrations of niacin (3, 4 and 5 g/kg) and pyridoxine (6, 12 and 18 mg/kg) and one with neither vitamin. The animals were divided into eleven experimental groups of six animals per group, and nine groups were fed on a standard diet with 7.5% fat and vitamin supplementation. Another group was fed with 7.5% fat without vitamin supplements. A control group received the standard diet (AIN-93M) without modifications (4% fat). The weight gain, food intake, serum and hepatic total cholesterol, serum cholesterol fractions (HDL, LDL, and VLDL), serum and hepatic triacylglycerols and hepatic and fecal lipid contents were measured after 30 days. The diet with the highest concentration of niacin and lowest concentration of pyridoxine had the lowest level of total hepatic cholesterol. Hepatic triacylglycerols were reduced by the highest concentration of niacin (5 g/kg), and this reduction was enhanced by increasing the pyridoxine concentration. The diets supplemented with niacin and pyridoxine reduced the levels of serum total cholesterol, LDL, VLDL, triacylglycerols and hepatic lipids. These effects on the lipid profile varied with the concentrations of the two vitamins and the interactions between them.

Development of oxidised and heat-moisture treated potato starch film.

This study investigated the effects of sodium hypochlorite oxidation and a heat-moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat-moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch.