Food Technology
Zohre Ganjeh-Soltanabadi; Rezvan Shaddel; Younes Zahedi
Abstract
IntroductionNowadays, the attention and desire of consumers to the role of food in health and nutrition has led the manufacturers to produce functional food and researchers to study this field. Polyphenols are secondary metabolites produced by many plants. They have anti-obesity, anti-inflammatory, anti-cancer ...
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IntroductionNowadays, the attention and desire of consumers to the role of food in health and nutrition has led the manufacturers to produce functional food and researchers to study this field. Polyphenols are secondary metabolites produced by many plants. They have anti-obesity, anti-inflammatory, anti-cancer and antioxidants activities. Despite all the mentioned benefits, due to the vulnerability of phenolic compounds to the environmental conditions and their low bioavailability in the digestive system, efforts have been made to encapsulate them with nanoniosomes. Encapsulation of polyphenolic compounds with nanoniosomes is an effective way to increase their stability and bioavailability as well ashinder their undesirable taste and smell. Niosomes are class of bi-layered structure formed by hydration of non-ionic surfactant, cholesterol or other amphiphilic molecules. This structure has two hydrophilic and hydrophobic properties, so it has the ability to be encapsulated with different solubility. Fortification food with polyphenols promotes community health. Therefore, the aim of this research was to produce nanoniosomes containing polyphenolic compounds, and to determine their important physical and chemical properties.Materials and MethodsIn this research, four polyphenol-loaded nanoniosomes were prepared using Span 60 and Tween 80 surfactants with a ratio of 3:1, and cholesterol with the concentration of 0, 10, 20 and 30 (mg/140 mg surfactant) as F1, F2, F3 and F4 treatments respectively. Physicochemical properties of the polyphenol-loaded niosomes (particle size, polydispersity index (PDI), zeta potential, encapsulation efficiency (EE)) were analyzed, and the formulation with the best characteristics was selected based on having the smallest size, less PDI and the highest EE. The selected formula was analyzed for morphology (scanning electron microscope (SEM)) and probably interactions (Fourier transforms infrared spectrometry (FTIR)). Additionally, the ability to preserve polyphenolic compounds as free or inside the nanonisomes during the storage period of 60 days was investigated. Further, the in vitro release of polyphenol from niosomes (gastric and intestinal simulated fluid) was also evaluated. The experiment was performed as completely randomized design (CRD) and the obtained data were analyzed with one-way analysis of variance (ANOVA).Results and DiscussionResults indicated that the effect of using different amounts of cholesterol on the average particle size (Z-average) of nanonisomes was significant (p<0.05). With increasing cholesterol up to 20 mg (F1 to F3), the Z-average decreased, but with further increase to 30 mg (F4), the Z-average increased. Different concentrations of cholesterol showed significant influence on the PDI of nanonisomes. The minimum value was observed for F3 (20 mg cholesterol) and the maximum for F4. The incorporation of cholesterol in the nanonisomes decreased the zeta potential (p<0.05), dedicated an increased electrostatical stability of the particle, and the values were in the range of -50.35 to -65.36 mV. The value of EE was in the range of 88-95%, and F3 treatment had the maximum EE. Based on particle size, PDI, zeta potential and EE, F3 was selected as the best nanoparticle for other assays. According to the FTIR results, there was no change in the spectrum of nanonisome (F3) containing polyphenol peaks, and the polyphenols were properly enclosed in the nanonisomal vesicles without changing its nature. SEM results also showed vesicles with a uniform and appropriate structure. Nanonisome (F3) containing polyphenol was more stable than the control sample (polyphenol) during 60 days of storage at ambient temperature, which indicated the higher potential of nanonisomes to preserve the polyphenolic compounds during storage. The release behavior in the simulated digestive system (gastric and small intestine media) indicated a diffusion-based release system, and the Kopcha model was the best model to describe the release behavior of polyphenol from the fabricated niosomes in the simulated digestive environment.ConclusionAccording to the results of this research, it is concluded that nanoencapsulation of polyphenols as a rich source of antioxidant properties inside the nanonisomes can be an effective strategy to maintain their nutritional value. These nanonisomes can be utilized to produce functional foods, and the effects of their addition on the physico-chemical properties of a model food can be investigated.
Hadise Karimi; Hojatollah Bodaghi; Ahmad Rajaei; Shideh Mojerlou
Abstract
Introduction: Fresh grapes (Vitis vinifera L.) show severe lesions at the post-harvest stage and during the storage period. Decreasing the quality of grapes in the post-harvest stage limits its consumption and commercialization. Some methods such as using bio-control agents, natural antimicrobials, physical ...
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Introduction: Fresh grapes (Vitis vinifera L.) show severe lesions at the post-harvest stage and during the storage period. Decreasing the quality of grapes in the post-harvest stage limits its consumption and commercialization. Some methods such as using bio-control agents, natural antimicrobials, physical methods, disinfectants agents ,GRAS, (ozone, ethanol, acetic acid) have been used to control Botrytis cinerea after harvest. Encapsulation of the essential oils will increase their ability by increasing the effectiveness of the essential oils. Currently, chitosan has been interested for encapsulating bioactive compounds, as they are generally known to be safe and possess superior biological properties such as biodegradability, biocompatibility and non-toxicity. The aim of this study was to encapsulate thyme essential oil in chitosan nanogels to enhance and maintain its antifungal effect against B. cinerea in vitro and in vitro on Shahroodi red grape. Materials and methods: For the purpose of this study, chitosan nanogels were first prepared and the infrared spectrum of chitosan-meric acid nanogels was measured using FT-IR430 infrared spectrophotometer at 20 ° C. The morphology of chitosan-meric acid nanogels and encapsulated essential oil was analyzed by SEM. Release test was then performed to determine the release rate of thyme essential oil encapsulated in chitosan-meric acid nanogels. Effect of chitosan-meristic acid nanogels at three levels of 0, 150 and 300 µl/L, pure thyme essential oil and thyme essential oil encapsulated in chitosan-meristic acid nanogels at three levels of 0, 75 and 150 µl / L in vitro and on the shelf life of grape fruits was studied under modified atmospheric conditions during 72 days storage at 2 to 4 °C. During storage, some traits such as firmness by manual penetrometer, electrical conductivity of fruit tissue, some components of fruit skin color and soluble solids were assessed by a refrectometer. Results and discusion: Infrared spectroscopy (FTIR) results confirmed the successful coupling between chitosan amin groups and carboxylic acid-meristic acid groups and scanning electron microscopy image showed that the particle size of chitosan-meric acid nanogel was than 100 nm. The Comparison of the particle size in the present study with the previous studies on the size of chitosan-meric acid nanogels was smaller and more uniform. These differences could be related to several reasons, transform the long chitosan chain into smaller fragments by initial sonication, the important role of ultrasound in the reduction of the particle size and passing the nanogels through the filter. Release test showed that the diffusion of thyme essential oil from chitosan-meric acid nanogels has a two-step process. The chitosan-meric acid nanogels prepared in this study have hydrophilic (chitosan polymer) and hydrophilic (meristic acid fatty acid chain) regions, which led to the gradual release of thyme essential oil due to their hydrophobic nature. The results of the infected packaged berries confirmed that with increasing concentration of thyme essential oil, the antifungal effect was also increased. Evaluation of the effects of essential oil and nanogels - essential oils on grape berries infected with pathogenic spores showed the highest number of spores in control treatment (10.125 × 105 per ml) and the lowest number in NE2 (1.375 × 105 per ml) were observed. Coating treatments of chitosan-meric acid nanogel and thyme essential oil encapsulated in chitosan-meric acid nanogels showed better results at higher concentrations, but in the case of essential oil, lower spores were observed. The lowest electrical conductivity and discoloration, the highest L * component and chroma index were observed in thyme essential oil treatment with concentration of 75 µl/l. The results showed that the lower concentrations of the essential oil in the control of botrytis cinerea was better than the pure essential oils, whereas in the experiments on the storage of grape fruit, the treatment of thyme essential oil with a concentration of 75 µl/l It showed the most favorable result. Based on the results of the present study, the effect of essential oil nano-gel and essential oil alone on the shelf life after harvesting of grapes packed with polyethylene film confirmed that the essential oil performance was better than the essential oil nanogel. The lower performance of the essential oil nanogel than that of the essential oil alone can be due to inhibition of the essential oil diffusion through the packaging film while, the encapsulated essential oil release slower than the essential oil alone, it is likely to have an effect longer than expected in this study for the storage period of the grape. Considering this case and the antimicrobial capability of essential oil nanogel, it is necessary to investigate the effect of essential oil nanogel compared to essential oil on longevity of grapes for a longer of storage period.
Mohammad Ganjeh; Seyed Mahdi Jafari; Mehrdad Niakosari; Ali-Mohammad Tamaddon; Yahya Maghsoudlou
Abstract
Introduction: In recent years, production of nutraceuticals by adding bioactive compounds and nutrients has been grown substantially. These compounds are generally sensitive to environmental or gastrointestinal conditions and their bioavailability is limited due to destructive reactions. One of the common ...
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Introduction: In recent years, production of nutraceuticals by adding bioactive compounds and nutrients has been grown substantially. These compounds are generally sensitive to environmental or gastrointestinal conditions and their bioavailability is limited due to destructive reactions. One of the common methods to reduce or prevent these kind of problems, is microencapsulation of valuable compounds in some materials which can protect them against environmental conditions, and enabling them to controlled release from trapped compounds at specific time and place. Orange peel oil, contains some important bioactive compounds such as limonene that is used in a variety of beverages, foods, cosmetics, pharmaceuticals and chemicals. D-limonene is the main constituent of orange peel oil, because it makes an 80-95% fraction of the orange peel oil volatile compounds, depending on fruit variety. In addition to its technological characteristics (flavor), D limonene can stop or delay the initiation of cancer. It can also be used as a safe alternative to antimicrobial compounds. Nevertheless, technological limitations (hydrophobic structure, high reactivity, sensitivity to oxidation and volatility) often avoid suitable use of this compound as a dietary supplement. Polysaccharides are among of the basic materials which are applied more in this field. Several factors such as cheap and easy access, having active groups interacting with hydrophobic and hydrophilic compounds, biodegradation, biocompatibility and relatively high thermal resistance, have turned them to be superior to lipid and protein carriers. One of the most important polysaccharide compounds existing in nature, is starch. It can be used as a carrier in encapsulation processes with different purposes, having advantages such as inexpensive, non-toxic, capable of recrystallization, the ability to form film and complex and resistant to various degrees of enzymatic hydrolysis. Spatial configuration of amylose is changed in the presence of ligands such as iodine and linear alcohols, resulting in a left-handed helix which can trap ligands within or between curvatures derived from glucose connections. One of the major structures which is created in the interaction of amylose and lipophilic substances, is known as V-amylose structure. V-amylose is a left-handed helix with an inner hole which ligands can be placed within it. The aim of this study was to determine the effectiveness of amylose in nanoencapsulation of limonene as a bioactive compound with desirable sensory characteristics using a thermo-mechanical stress.
Materials and methods: Based on the analysis of pure limonene samples (Sigma-Aldrich) as well as samples used in this study, more than 92% of examined sample comprised of D-limonene. In order to prepare amylose nanoparticles containing limonene, 0.1 molar solution of potassium hydroxide (Merck, Germany) was prepared in deionized water and then high amylose corn starch (HACS) (Sigma-Aldrich (St. Louis, MO, USA) with 70% amylose was added to it in the ratios of 2: 4% while stirring continuously for 30 minutes at 80°C. Limonene was then used in the ratios of 5: 10% of HACS was added to the suspension and stirring continued for 1 minute. Initial suspension has been processed by using ultrasound system (Model UP100- Hescheler Company, Germany) with 100 W power and frequency of 30 kHz for 9 and 18 minutes. The viscosity of amylose suspensions containing nanoparticles with different formulations was measured by using a capillary viscometer (Schott-Gerate-Capillary-Viscometer-525-00- Germany). Size and zeta potential was measured by using dynamic light scattering (DLS) and Nanotrac Flex In-situ Particle Size Analyzer devices and Microtrac ZETA-check determined. The morphology of nanoparticles was studied using a scanning electron microscopy (TESCAN-Vega3- Czech Republic). Microencapsulation efficiency and loading efficiency were determined by using spectrophotometry.
Results and Discussion: In all formulations, particle sizewere less than 50 nm. Starch granules were exposed to cavitation stress by applying the ultrasonic process .The constant formation of bubbles creates a mechanical impact with high energy on starch granules during bursting. Fast impingement of fluid to granule surfaces, hitting particles to each other as well as resistant of the granules against fluid stream cause breaking of starch particles into nanoparticle scales. The highest amount of zeta potential was related to the sample which had the highest starch and limonene concentration. Amylose concentration had the main effect on zeta potential changes. Electrostatic charges can be the main reasons for the higher zeta potential in samples with 4% amylose concentration. More increasing in surface active agents of amylose, namely ionized hydroxyl groups of glucose molecules leads to increasing in surface charge, and results in zeta potential. The most impact on solutions viscosity is related to amylose concentration. Generally, increasing the amylose concentration leads to increasing the solution viscosity, in other side, with ultrasound treatment, the amount of this index was reduced and the solution became more fluent. Microencapsulation and loading efficiency values ranged between 28-82% and 0.38-1.63% respectively. The limonene concentration had the most impact on the efficiency in various formulations. At similar treatments with %4 amylose concentration and 9 min sonication period, by increasing the amount of limonene from %5 to 10, microencapsulation and loading efficiency were increased from %31 to %82 (%62 growth) and from 0.52 to 1.41 (%63 growth) respectively.
Afshin Faridi Esfanjani; Seyed Mahdi Jafari; Elham Assadpour; Habibollah Mirzaee
Abstract
Introduction: Controlling and targeting release of bioactive compounds have a key role in improving their functional properties such as antioxidant and anti-disease activities. Encapsulation is one of the best methods for protection and controlling release of bioactive ingredients. Indeed, in this process, ...
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Introduction: Controlling and targeting release of bioactive compounds have a key role in improving their functional properties such as antioxidant and anti-disease activities. Encapsulation is one of the best methods for protection and controlling release of bioactive ingredients. Indeed, in this process, protection and controlling release of ingredients as core materials are performed by surrounding of them via variety of wall materials. Emulsions are most popular encapsulation systems that are classified in variety types such as single layer emulsion, multi-layer emulsion, doubleemulsion, and etc. Hydrophilic bioactive compounds can be loaded in inner aqueous phase of water in oil in water (W/O/W) double-emulsions. The stability of doubleemulsions is low due to presence of two interfaces in them.Applying a thermodynamically stable W/O emulsion (e.g., micro-emulsion) as a primary emulsion and using of complex biopolymers as emulsifier and stabilizer in outer phase of doubleemulsions can improve their stability (Dickinson, 2011; Boyer et al, 2012).Saffron bioactive compounds include crocin, picrocrocin, and saffranal are widely used for a variety of functional and healthy goals in food and pharmaceutical industries. These compounds have many different functions, including anti-carcinogenic, anti-oxidant, anti-depressant, anti-apoptotic, anti-tussive, anti-nociceptive, anti-inflammatory and anti-thrombotic properties (Moraga et al, 2004).In the present study, our main goal was kinetically evaluated release of crocin, picrocrocin and saffranal from inner phase to outer phase of doubleemulsion during 22 days storage by Zero order, Fist order, Higuchi, and Hixson-Crowell.Materials and method: Saffron was provided from Torbatheydariyeh farms, Khorasan-e-razavi, Iran. Sunflower oil and sodium azide were purchased from FRICO (Sirjan, Iran) and Sigma-Aldrich (St. Louis, USA), respectively. Whey protein concentrate (80% protein) and sorbitanmonooleate (span 80) were obtained from Sapoto cheese (USA) and Merck (Germany), respectively. Maltodextrin was obtained from Qinhuangdao starch Co. (DE 16-20, China) and citrus pectin with a degree of methyl esterification of 71.1% and galacturonic acid >65% was purchased from MP biomedical (Netherland). All other chemicals used in this study were of analytical grade.For extraction of crocin, picrocrocin and saffranal, a total of 10 grams of saffron sample was macerated in 150 mL of water in a glass bottle, covered with aluminum foil (to prevent direct exposure to light), and was placed in an incubator shaker (Kavooshmega, Iran) for 24 hours at 30oC. Then, this solution was homogenized (10000 rpm for 10 minutes, HeidolphSilentcrusher, Germany) for maximum extraction of saffron compounds. Finally, the extract was filtered under vacuum by using a Whatman No. 1 (11 mm) filter paper, and kept in the freezer at -18oC prior to any examination. ISO/TS 3632 procedure (2003) was used for the measurement of saffron compounds. The doubleemulsions were prepared in two-step:(a) Frist, primary W/O micro-emulsions were produced by two formulations: 60:30:10% and 62:33:5% of sunflower oil, span 80, and saffron extract, respectively. (b) Then, the W/O micro-emulsions was gradually added into the outer aqueous phase contains why protein concentrate (WPC)/maltodextrin or WPC/pectin/maltodextrin while blending by a homogenizer (12000 rpm for 5 minutes at 10oC, HeidolphSilentcrusher, Germany) and then these coarse emulsions were further emulsified using mentioned homogenizer (15000 rpm for 8 minutes at 10oC). All doubleemulsions were composed of 25% primary emulsion and 75% outer aqueous phaseDroplet size of doubleemulsions after one day and 22 days storage weremeasured using Zetasizer (Malvern Instruments, Worcestershire, UK).The released components in the outer aqueous phase were measured by evaluation of encapsulation efficiencyof the ratio of crocin, picrocrocin, and saffranalat a specific time:E (%) = 100- (C2×100/C1) (1)Where C2 is the percentage of crocin, picrocrocin and saffranal in outer aqueous phase and C1 equals to the percentage of compounds in inner aqueous phase.C2 is a released into outer aqueous phase relative to the total amount present in the outer aqueous phase if all compounds were released (M ∞).The viscosity of emulsions was measured using a programmable viscometer (model LVDV -II + Pro, Brookfield Engineering Laboratories, USA) and by a ULA spindle.The released are kinetly evaluated by Zero order, Fist order, Higuchi, and Hixson-Crowell.The experiments were all carried out in triplicate. The collected data were analyzed by one-way ANOVA; the means were compared by the Duncan's multiple range tests at the 5% level through SPSS version 21 (IBM, USA).Results and Discussion: As shown in fig. 1, the droplet size of produced W/O micro-emulsions were lower than 200 nm. In fact, these droplets are water droplets containing bioactive compounds of saffron dispersed within oil phase that surrounded with Span 80 (Fig. 2).Also, it was found that by increase of saffron extract (from 5% to 10%) as dispersed phase in W/O micro-emulsions, droplet size and poly-dispersityindex (PDI) weresignificantly (P< 0.05) affected (Table. 3).As shown in table. 4, crocin, picrocrocin, and saffranal had a same release trend, but the release rate of crocin was lower than saffranal and picrocrocin. As regard to R2, SSE, and RMSE from kinetic modeling in table. 5, the firstorder was a best model for release of crocin, and zero order was a best model for release of picrocrocin and saffranal. Also, kinetic date of release showed that the high release of crocin, saffranal, and picrocrocin was observed by increasing the dispersed phase content of primary W/O micro-emulsion and also it was found that WPC/pectindelayed the release of encapsulated ingredients more than single WPC (Table. 5). Indeed, the using of complex biopolymers as the external binary film of doubleemulsions causes a resistance to release for inner compounds (Dickinson, 2011).As shown in fig. 3, the viscosity of doubleemulsions stability with WPC/pectin complex was higher than doubleemulsions stabilized by only WPC. This can confirm the higher stability of stabilized doubleemulsions with complex biopolymers (Olivieri et al, 2003).
