RESUMO
Ilex paraguariensis is a native tree from South America known for the presence of bioactive compounds, and its processed leaves are consumed as hot and cold infusions. After harvest (step 1), the leaves are subjected to flame blanching to inactive the enzymes (step 2), followed by drying and milling (step 3). The impacts of I. paraguariensis processing on leaf composition were investigated by extracting the major compounds (chlorogenic and isochlorogenic acids (3-CQA, 4-CQA, 5-CQA, 3,4-DQA, 3,5-DQA and 4,5-DQA), p-coumaric acid, caffeine and rutin) using different ratios of ethanol and water as extraction solvent (EW 25:75, 50:50, and 75:25 (w/w)). The solvent ratio of EW 50:50 was more effective in extracting the chlorogenic acids isomers, with retention of chlorogenic acids of 3463, 9485, and 9516 µg mL- 1 for steps 1, 2, and 3, respectively. Rutin and p-coumaric acid exhibited similar behavior with the increment of processing steps; however, p-coumaric acid was only detected in steps 2 and 3 for the solvent ratios EW 50:50 and 25:50. The caffeine extraction from I. paraguariensis varied from 936 to 1170 µg mL- 1 for all processing steps, with emphasis on its concentration extracted in step 1. The evolution of processing steps led to a higher retention of phenolic compounds from I. paraguariensis, which was not observed when using different solvent ratios, and the solvent ratio EW 50:50 was more effective for the extraction of chlorogenic acids. The successful extraction of chlorogenic acids from I. paraguariensis in this study proved to be a promising alternative for the use of yerba mate beyond the cuia cup.
Assuntos
Ilex paraguariensis , Cafeína , Extratos Vegetais , Rutina , SolventesRESUMO
The demand for natural compounds to replace synthetic additives has aroused the interest of different sectors of society, especially the scientific community, due to their safety, biocompatibility, biodegradability and low toxicity. Alternative sources for antimicrobial compounds have been explored, such as fruit pomace. These by-products have essential compounds in their composition with different potential for application in food and packaging. In this context, this review systematizes the use of pomace from different fruits as a source of antibacterial compounds. Also, it summarizes the extraction methods and the applications of these compounds. Grape pomace, cranberry, and apple extracts are the most explored for antibacterial control, especially against genus Listeria, Salmonella, Staphylococcus, and Escherichia. In addition, phenolic acids, anthocyanins, flavonoids, and proanthocyanins are the main compounds identified in the studied fruit pomace extracts. In the reviewed articles, the biocompounds recovery is performed by methods with the absence of high temperatures (>80 °C); in some studies, the solid-liquid extraction method at mild temperatures (<30 °C) was well explored, using ethanol and water as solvent. The use of fruit processing by-products for bacterial control highlights the possibility of favoring the three pillars of sustainability (social, economic, and environmental) in the food industry.
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BACKGROUND: Red araçá is a Brazilian native species whose fruits are rich in phenolic acids, flavonoids, anthocyanins, and carotenoids. To preserve the properties of compounds during processing, red araçá pulp (RAP) was encapsulated by hydrolyzed pinhão starch (PS), tara gum (TG), and arabic gum (AG) in different blends in equal proportions, serving as a coating material. RESULTS: Fresh RAP had a gallic acid equivalent of 3098 mg per 100 g of dry weight, 156.29 µg ß-carotene per gram of dry weight, total anthocyanins of 18 mg per 100 g of dry weight and exhibited high antioxidant activity. The highest encapsulation efficiency achieved with the PS, TG, and AG blend was 80.4% for the total carotenoids, and that for the total anthocyanins was 76% with the TG and AG blend. Only one step of antioxidant activity degradation was identified, and the carrier system PSTG was efficient at maintaining the antioxidant activity, with half-life of 23.60-37.27 days. CONCLUSION: The use of PS alone as a coating material or associated with TG and AG gums resulted in improved retention of bioactive compounds, these being an excellent alternative coating material since they improved the stability of the antioxidant activity of RAP. © 2020 Society of Chemical Industry.
Assuntos
Fabaceae/química , Goma Arábica/química , Extratos Vegetais/química , Gomas Vegetais/química , Psidium/química , Amido/química , Antocianinas/química , Brasil , Carotenoides/química , Flavonoides/química , Frutas/química , HidróliseRESUMO
Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.
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Syzygium , Antocianinas/análise , Antioxidantes , Cromatografia Líquida de Alta Pressão , Frutas/química , Fenóis/análise , Extratos VegetaisRESUMO
BACKGROUND: pH-sensitive indicator membranes, which are useful for pharmaceutical, food, and packaging applications, can be formed by encapsulating halochromic compounds within various solid supports. Accordingly, electrospinning is a versatile technique for the development of these indicators, by entrapping pH dyes within ultrafine polymer fibers. RESULTS: The ultrafine zein fibers, containing 5% (w/v) anthocyanins, had an average diameter of 510 nm. The pH-sensitive membrane exhibited color changes from pink to green when exposed to acidic and alkaline buffers, respectively. The contact angle was negligible after 10 and 2 s for neat and 5% anthocyanin-loaded zein membranes, respectively. CONCLUSION: The pH membranes exhibited color changes in a board pH range, which can potentially be used in various active packaging applications. © 2017 Society of Chemical Industry.
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Antocianinas/química , Polímeros/química , Zeína/química , Cor , Concentração de Íons de HidrogênioRESUMO
BACKGROUND: The microstructure and the physical, mechanical, barrier and thermal properties of films based on different concentrations of protein isolated from croaker waste (CPI) and palm oil (PO) were analyzed. Films were elaborated by a casting technique using 2, 3 and 4 g CPI 100 g(-1) of a filmogenic solution and 0, 10 and 20 g of PO 100 g(-1) CPI. RESULT: Microstructure of the film surfaces of CPI with PO showed no presence of lipid droplets dispersed in the filmogenic matrix, although a rough surface was present. Films with 3% and 4% CPI and 20% PO had the lowest rates of water vapor permeability. When there was an addition of PO to the reduced tensile strength of the films, regardless of the concentration of CPI, this addition reduced the elongation of films with 3% and 4% CPI; however, it did not influence films with 2% CPI, which did not differ from the control film (0% OP). Thermal analysis revealed that films with the highest PO percentage had a lower initial weight loss when compared with other films, due to higher hydrophobicity. CONCLUSION: The use of protein isolate obtained from fish residues of low commercial value and palm oil is viable for the production of biodegradable films because the latter constitute good barrier properties and thermal stability. © 2015 Society of Chemical Industry.
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Proteínas de Peixes/química , Peixes/classificação , Óleos de Plantas/química , Animais , Embalagem de Alimentos , Teste de Materiais , Membranas Artificiais , Microscopia Eletroquímica de Varredura , Óleo de Palmeira , TermogravimetriaRESUMO
Estimates of dietary intake of polyphenols have been limited to specific samples from certain population groups, and different databases have been used to quantify the levels of these compounds, which makes it difficult to compare results. PURPOSE OF REVIEW: This review collated estimates of polyphenol intake from population studies including adults and elderly from different parts of the world by using a single database: Phenol-Explorer. RECENT FINDINGS: Through seven population-based studies performed in five different countries, it was possible to identify that Brazil was the country with the lowest intake of polyphenols, whereas Poland had the highest dietary intake. The most ingested subclasses of polyphenols in different countries were phenolic acids and flavonoids, and non-alcoholic beverages (coffee, tea, and orange juice) were the foods that most contributed to the intake of polyphenols. Despite the attempt to standardize this study to obtain worldwide intake estimates that could be comparable, gaps were found regarding the assessment of food consumption, standardization to obtain the polyphenol content of foods in Phenol-Explorer, calculation in aglycone equivalents, and caloric adjustment of the estimates. There is a need for more studies on the dietary polyphenols intake of representative samples of populations from different countries to collate more data on the quantities consumed and the main contributing foods.
Assuntos
Dieta , Polifenóis , Humanos , Polifenóis/análise , Idoso , Adulto , Flavonoides/análise , Brasil , Chá/química , Polônia , Pessoa de Meia-Idade , HidroxibenzoatosRESUMO
There is a growing interest in exploring new natural sources of colorants. This study aimed to extract anthocyanins from broken black bean hulls (Phaseolus vulgaris L.) by modifying water with a eutectic mixture (choline chloride:citric acid (ChCl:Ca)). Ultrasound-assisted extraction (UAE) was employed and optimized in terms of temperature (30-70 °C), ultrasound power (150-450 W), and eutectic mixture concentration in water (1-9% (w/v)), resulting in an optimal condition of 66 °C, 420 W, and 8.2% (w/v), respectively. The main quantified anthocyanins were delphinidin-3-O-glycoside, petunidin-3-O-glycoside, and malvidin-3-O-glycoside. The half-life of the anthocyanins at 60 °C increased twelvefold in the eutectic mixture extract compared to the control, and when exposed to light, the half-life was 10 times longer, indicating greater resistance of anthocyanins in the extracted eutectic mixture. Additionally, the extracts were concentrated through centrifuge-assisted cryoconcentration, with the initial cycle almost double the extract value, making this result more favorable regarding green metrics. The first concentration cycle, which showed vibrant colors of anthocyanins, was selected to analyze the color change at different pH levels. In general, the technology that uses eutectic mixtures as water modifiers followed by cryoconcentration proved to be efficient for use as indicators in packaging, both in quantity and quality of anthocyanins.
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Biodegradable starch foam trays offer an eco-friendly substitute for petroleum-based single-use packaging, notably polystyrene foams. However, they lack flexibility, tensile strength, and water-sensitivity, addressable through lignocellulosic reinforcement. This study aimed to develop biodegradable starch foam trays filled with different food-chain side streams for sustainable alternative packaging. Corncob, soybean straw, cassava peel, araucaria seed hull, yerba mate stalks and yerba mate leaves petiole were collected, dried and ground to <250 µm. The trays were filled with 13 % (w/w) of each food-chain side streams and produced by hot molding. The trays morphology, moisture, water activity (aw), thickness, bulk density, tensile strength, elongation at break, Young's modulus, bending strength, maximum deflection, and sorption isotherms were investigated. Reinforcements slightly increased the foams bulk density, reduced the tensile strength and maximum deflection and while bending strength increased from 0.20 MPa to 1.17-1.80 MPa. The elasticity modulus decreased by adding any filling, that resulted in ductility improvement; however, these packaging have moisture-sensitive material especially for aw higher than 0.52, which drives the use recommendation for dry products storage or shipping/transport. The biodegradable starch foam trays filled with side streams were successfully produced and offer excellent alternative to petroleum-based packaging low-density material with bending strength improved.
Assuntos
Amido , Resistência à Tração , Amido/química , Água/química , Embalagem de Alimentos/métodos , Manihot/químicaRESUMO
The physicochemical properties of starch vary depending on the botanical sources, thereby influencing the gelatinisation/retrogradation properties and subsequently affecting the hydrogels characteristics. This study aimed to assess the influence of botanical sources influence on starch and hydrogel properties using non-conventional starch derived from guabiju, pinhão, and uvaia seeds. Hydrogels were prepared by starch gelatinisation followed by 6 h ageing period at room temperature (20 ± 2 °C) and subjected to five freeze-thaw cycles. Pinhão starch exhibited a higher viscosity peak and breakdown, along with a lower final viscosity and setback, compared to guabiju and uvaia starches. The significantly different pasting properties influenced the porous microstructure, water absorption (p-value: 0.01), and resistance of the hydrogels (p-value: 0.01). The guabiju starch hydrogels showed a uniform pore structure without cavities, whereas pinhão and uvaia starch hydrogels exhibited agglomerated and spongy pore structures. Furthermore, the guabiju starch hydrogel demonstrated the lowest water absorption (4.56 g/g) and the highest compression resistance (1448.50 g) among all the studied starch hydrogels. In contrast, the pinhão starch hydrogel showed the highest water absorption (7.43 g/; p-value: 0.01) among all studied starch hydrogels. The hardness of uvaia starch hydrogel did not differ significantly from the guabiju and pinhão starch hydrogel. The different non-conventional starches reveal important variations in the hydrogels characteristics. This provides insights into how amylose and amylopectin interact and present alternatives for using these unique starch-based hydrogels in diverse applications.
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Hidrogéis , Amido , Amido/química , Amilose/análise , Sementes/química , Água/químicaRESUMO
The yerba mate (Ilex paraguariensis A.St.-Hil.) is abundant on phenolic compounds and their preservation by encapsulation can promote increased stability. The objective was to produce mate extract with a high concentration of bioactive compounds, microencapsulate and characterize them. A commercial yerba mate was used to produce the extracts and select the best extraction solvent (ethanol, water, and ethanol:water (1:1). The ethanol:water extract was encapsulated at 1:1 (w/w) by fructooligosaccharide (FOS) and gum arabic (GA), in different combinations: FOS, GA:FOS (1:3), GA:FOS (1:1), GA:FOS (3:1) and GA. The encapsulation of chlorogenic acids was around 80%, considering the major phenolic compounds by HPLC. Thermal stability, by DSC, increased at treatments FOS, GA:FOS (1:3), and GA:FOS (1:1) compare to the unencapsulated extract, and changes were noticed in ATR-FTIR bands and antioxidant activity. The encapsulated phenolic compounds from I. paraguariensis can be stable in food under heat processing.
Assuntos
Ilex paraguariensis/química , Fenóis/análise , Extratos Vegetais/química , Antioxidantes/análise , Ácido Clorogênico/química , Goma Arábica/química , Temperatura Alta , Oligossacarídeos/química , Folhas de Planta/química , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
The objectives of this study were to characterize zein fibers and capsules prepared by electrospinning and electrospraying techniques, respectively, and then use them to encapsulate folic acid. Folic acid containing fibers and capsules (0.5, 1.0, and 1.5%, w/v) were submitted to thermal treatment (100, 140, and 180⯰C) and ultraviolet A light (UVA) irradiation to evaluate the resistance of folic acid. Zein fibers and capsules containing folic acid showed high encapsulation efficiency (>80%). Unencapsulated folic acid showed a reduction in folic acid content from 17.17⯵g/mL to 5.44⯵g/mL (approximately 70%) when exposed to 180⯰C. Photodegradation of unencapsulated folic acid lowered its concentration from 17.17⯵g/mL to 12.58⯵g/mL (~26% of reduction), when exposed for 1â¯h to UVA irradiation. However, folic acid concentration when encapsulated in fibers (1.5%) was maintained or only slightly reduced from 9.73⯵g/mg to 8.88⯵g/mg after thermal treatment at 180⯰C. The capsules containing 1.5% of folic acid also presented a slight reduction in folic acid concentration from 8.84⯵g/mg to 7.88⯵g/mg when exposed to 24â¯h of UVA irradiation. Zein fibers and capsules containing folic acid present promising characteristics for application in foods that require thermal processing or exposure to irradiation.
Assuntos
Ácido Fólico , Nanocápsulas/química , Zeína/química , Estabilidade de Medicamentos , Técnicas Eletroquímicas , Ácido Fólico/análise , Ácido Fólico/química , Ácido Fólico/efeitos da radiação , Nanocápsulas/efeitos da radiação , Fotólise , Polímeros , Temperatura , Raios Ultravioleta , Zeína/efeitos da radiaçãoRESUMO
The objective of this study was to evaluate the effects of the heat-moisture treatment (HMT) applied to paddy rice grains on the physicochemical properties, in vitro starch digestibility, and molecular weight distribution of proteins in rice flour. The paddy rice grains were adjusted to 13%, 16%, and 18% moisture and autoclaved at 121°C for 30 and 60min. The HMT promoted a reduction of the amylose content, the swelling power, and the solubility of the rice flour. Changes in the relative crystallinity and molecular weight of the proteins extracted with a sodium phosphate buffer containing 2.0% sodium dodecyl sulfate (SDDS) were observed in HMT samples. The different methods for the quantification of resistant starch resulted in distinct resistant starch contents. The HMT (18%-60min) promoted an increase in resistant starch content and the HMT (16%-60min) caused an increase in the slowly digestible starch in the rice flour.
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Oryza/química , Amido/química , Peso MolecularRESUMO
The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films.
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Sorghum/química , Sorghum/metabolismo , Amido/análise , Amido/metabolismo , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/metabolismo , Grão Comestível/química , Grão Comestível/metabolismo , Oxirredução , Permeabilidade , Solubilidade , Vapor/análise , Resistência à Tração , Difração de Raios XRESUMO
Black bean protein hydrolysates obtained from pepsin and alcalase digestions until 120min of hydrolysis were evaluated by gel electrophoresis, relative fluorescence intensity, emulsifying properties, light micrograph of emulsions and in vitro antioxidant activity. The emulsion stability of the bean protein hydrolysates were evaluated during 30days of storage. The pepsin-treated bean protein hydrolysates presented higher degree of hydrolysis than the alcalase-treated protein hydrolysates. The alcalase-treated bean protein hydrolysates showed higher surface hydrophobicity. Moreover, the protein hydrolysates obtained with alcalase digestion presented higher emulsion stability during 30-days than those obtained from pepsin digestion. The protein concentrate and especially the hydrolysates obtained from alcalase digestion had good emulsion stability and antioxidant activity. Thus, they could be exploited as protein supplements in the diet as nutritional and bioactive foods.
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Phaseolus/química , Phaseolus/fisiologia , Hidrolisados de Proteína/química , Fenômenos Químicos , Digestão/fisiologia , Eletroforese em Gel de Poliacrilamida/métodos , Emulsões/química , Emulsões/metabolismo , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Hidrolisados de Proteína/metabolismoRESUMO
The aim of this study was to produce ultrafine fibers from zein incorporated with a complex of eucalyptus essential oil (EEO) and ß-cyclodextrin (ß-CD) with antimicrobial properties by electrospinning technique. The EEO was characterized by chemical composition and antimicrobial tests against three Gram positive and four Gram negative bacteria. The inclusion complex (IC) was prepared with ß-CD and EEO by co-precipitation technique and added at different concentrations in zein polymer solution using aqueous ethanol as solvent. The morphology, thermal properties, functional groups, and antimicrobial activity against L. monocytogenes and S. aureus of the ultrafine fibers were evaluated. The composite membranes containing 24% IC exhibited a greater reduction of growth as compared to the fibers without addition of IC. For L. monocytogenes the growth reduction was 28.5% and for S. aureus it was 24.3%. The electrospun IC-ß-CD/EEO composite membranes are promising for use in antimicrobial applications, such as food packaging.
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Eletricidade , Eucalyptus/química , Óleos Voláteis/química , Zeína/química , Zeína/farmacologia , beta-Ciclodextrinas/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Membranas Artificiais , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacosRESUMO
Biodegradable films from native or acetylated starches with different amylose levels were prepared. The films were characterized according to the mechanical, water vapor barrier, thermal, and biodegradability properties. The films from acetylated high amylose starches had higher moisture content and water solubility than the native high amylose starch film. However, the acetylation did not affect acid solubility of the films, regardless of the amylose content. Films made from high and medium amylose rice starches were obtained; however low amylose rice starches, whether native or acetylated, did not form films with desirable characteristics. The acetylation decreased the tensile strength and increased the elongation of the films. The acetylated starch-based films had a lower decomposition temperature and higher thermal stability than native starch films. Acetylated starches films exhibited more rapid degradation as compared with the native starches films.
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Amilose/análise , Oryza/química , Amido/química , Acetilação , Temperatura Alta , Estrutura Molecular , Solubilidade , Vapor , Resistência à TraçãoRESUMO
The objective of this study was to evaluate the effects of starch source and amylose content on the expansion ratio, density, and texture of expanded extrudates, as well as to investigate the structural and molecular changes that occur in starch granules as a function of extrusion. The starches employed were rice starches (8%, 20%, and 32% amylose), carioca bean starch (35% amylose), and Hylon V® corn starch (55% amylose). The extrudates from rice starches containing 20% and 32% amylose exhibited the highest expansion ratio, while, extrudates from Hylon V® corn starch containing 55% amylose exhibited the lowest expansion ratio. The hardness values of the extrudates with 55% amylose were twice those of the extrudates with 20%, 32%, and 35% amylose. An additional finding was that although the amylopectin promoted the expansion of the gelatinized starch matrix, it failed to strengthen and sustain the walls of the extrudate bubbles during expansion.
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Amilopectina/análise , Amilose/análise , Fabaceae/química , Oryza/química , Amido/química , Zea mays/química , Análise de Alimentos , Gelatina/química , Estrutura MolecularRESUMO
This study aims to evaluate the effects of polishing and parboiling on proximate composition, structure, phenolic compounds, antioxidant activity, cooking time and hardness of IAC-600 black rice cultivar and MPB-10 red rice lineage. Proximate analysis and light micrographs revealed higher migration of red rice proteins than black rice proteins to the endosperm as a result of parboiling. Parboiling reduced the ash content of red rice while no difference was determined in black rice. Gelatinized starch granules from both genotypes showed similar appearance. There was a decrease in relative crystallinity on both black and red rice subjected to parboiling, which was an indicative of crystallites disruption. Polishing removed more than 90% of free phenolics for both genotypes, while parboiling allowed the partial preservation of free phenolics content in polished rice. Parboiling induced an increase in the cooking time of red rice, but a decrease in the cooking time of black rice.
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Culinária , Oryza/química , Cor , Genótipo , Dureza , Temperatura Alta , Oryza/genética , Fenóis/análise , Amido/químicaRESUMO
Acetylation and oxidation are chemical modifications which alter the properties of starch. The degree of modification of acetylated and oxidized starches is dependent on the catalyst and active chlorine concentrations, respectively. The objective of this study was to evaluate the effect of acetylation and oxidation on the structural, morphological, physical-chemical, thermal and pasting properties of barley starch. Barley starches were acetylated at different catalyst levels (11%, 17%, and 23% of NaOH solution) and oxidized at different sodium hypochlorite concentrations (1.0%, 1.5%, and 2.0% of active chlorine). Fourier-transformed infrared spectroscopy (FTIR), X-ray diffractograms, thermal, morphological, and pasting properties, swelling power and solubility of starches were evaluated. The degree of substitution (DS) of the acetylated starches increased with the rise in catalyst concentration. The percentage of carbonyl (CO) and carboxyl (COOH) groups in oxidized starches also increased with the rise of active chlorine level. The presence of hydrophobic acetyl groups, carbonyl and carboxyl groups caused a partial disorganization and depolymerization of starch granules. The structural, morphological and functional changes in acetylated and oxidized starches varied according to reaction conditions. Acetylation makes barley starch more hydrophobic by the insertion of acetyl groups. Also the oxidation promotes low retrogradation and viscosity. All these characteristics are important for biodegradable film production.