Food Technology
Rezvan Shaddel; Shadi Rajabi Moghaddam
Abstract
Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ...
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Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ways to overcome this issue. In this research, caffeine was encapsulated in nanoliposomes coated with chitosan and then the drink powder enriched with caffeine nanochitosome was produced.
Materials and methods
In this research, pure caffeine powder was purchased and stored in dry environment at room temperature. Ethanol (96%) and acetic acid were obtained from Mojallali Company, Tween 80 from Merck Company (Germany), lecithin (P3556), cholesterol (C8667), and chitosan (medium molecular weight) purchased from Sigma Aldrich Company (Germany). Sugar, essential oil and citric acid used in the formulation of the drink were purchased from a local store.
First, nanochitosomes in ratios of 9:1, 8:2 and 7:3 lecithin-cholesterol, were prepared using thin-layer hydration method. Then, the particle size and zeta potential were measured to determine the characteristics of the produced particles. Encapsulation efficiency was measured for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios. The stability of the chitosomal sample with a ratio of 9:1 lecithin-cholesterol was evaluated through visual observation of precipitation formation and the amount of release of encapsulated caffeine during 60 days of storage at ambient temperature was calculated. FTIR was performed for each of the components of the wall of chitosomes, caffeine powder, chitosomal solution containing caffeine and chitosomal solution without caffeine with a ratio of 9:1 lecithin-cholesterol. Nanochitosomes with 9:1 lecithin-cholesterol ratio were used in the formulation of beverages due to having the smallest particle size, favorable zeta potential, the highest microencapsulation efficiency, and high stability during storage. The drink samples were prepared in different formulations (samples containing 3 and 5% free caffeine solution, samples containing 3 and 5% chitosomal caffeine solution and the control sample). Then, the drinks were evaluated in terms of sensory characteristics and other physico-chemical characteristics (pH, acidity, Brix degree, etc.). The drinks produced were turned into powder with a freeze-dryer machine, and two important characteristics of powdered products, i.e. water solubility index and their hygroscopicity, were evaluated.
Results and Discussion
The average particle size and zeta potential for different ratios of lecithin -cholesterol were obtained in the range of 133.3-443.6 nm and +40.96 to +48.36, respectively. The encapsulation efficiency for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios were 91.2%, 86.18% and 79.09 %, respectively. The chitosomal sample with 9:1 lecithin-cholesterol ratio showed good stability during 60 days of storage at ambient temperature. FTIR results showed that caffeine was loaded in nanochitosomes. The results of the sensory evaluation of the prepared beverages showed the acceptability of the taste of the samples containing caffeine nanochitosome compared to the samples containing free caffeine, which indicates the success of chitosomal nanocarriers in covering the bitter taste of caffeine. The results of measuring the color of different drink samples showed that there is no significant difference between the color of samples. The results of measuring pH and acidity did not show significant differences between different drink samples. The results of measuring the solubility of different drink powder samples showed that the samples containing caffeine nanochitosomes have low solubility compared to other drink powder samples. Also, the hygroscopic amount of the drink powder containing caffeine nanochitosomes was lower than the other samples, which is considered as an advantage for powdered products.
The results obtained in this research showed that nanochitosomes are an efficient system in covering the bitter taste of caffeine. Therefore, with the production of caffeine nanochitosomes and its usage in the formulation of powder drinks, it is possible to produce energizing and desirable drinks without the need to use high amounts of sucrose.
Food Technology
Masoumeh Salamatian; Younes Zahedi; Rezvan Shaddel
Abstract
Introduction
Capparis spinosa is a perennial herb from the Capparidaceae family that is mainly distributed in arid and semi-arid regions. Its fruits are oval shaped, approximately 3 cm long, greenish in color with red pulp. Capparis spinosa extract is a rich source of phenolic compounds. The instability ...
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Introduction
Capparis spinosa is a perennial herb from the Capparidaceae family that is mainly distributed in arid and semi-arid regions. Its fruits are oval shaped, approximately 3 cm long, greenish in color with red pulp. Capparis spinosa extract is a rich source of phenolic compounds. The instability of phenolic compounds in the environmental conditions as well as their bitter or astringent taste has created challenges for the use of these compounds in the food industry. Encapsulation is a method that can positively affect bioaccessibility and bioavailability as it ensures the coating of the active component and its targeted delivery to a specific part of the digestive tract and controlled release. Encapsulation using nanoliposomes seems to be an appropriate technique to overcome these issues. Nanoliposomes are the nanometric version of liposomes. Liposomes are spherical particles composed of lipid molecules (mainly phospholipids) that tend to accumulate in polar solvents such as water in the form of bilayer membranes. Encapsulation with liposomes is an effective way to preserve the intrinsic properties of bioactive compounds during storage and production of foods fortified with them, as well as a physicochemical barrier against prooxidant agents such as free radicals, oxygen and UV.
Materials and Methods
Materials: Capparis spinosa fruits, were collected from subtropical regions of Ilam province (Iran). Folin ciocalteu, gallic acid and tween 80 from Merck (Germany), cholesterol and phosphatidylcholine from Sigma- Aldrich (Germany) were obtained.
Methods: The extract was obtained from capparis spinosa fruit powder using ultrasonic bath (Backer, vCLEAN 1- L6, Iran). The phenolic content was measured by folin ciocalteu method. Nanoliposomes containing capparis spinosa extract were prepared in ratios of 60- 0, 50- 10, 40- 20 and 30- 30 w/w lecithin- cholesterol. Then, particle size, PI and zeta potential were measured by DLS (Horiba, Japan) at 25 oC. After calculating the encapsulation efficiency using its corresponding equation, the investigation of possible reactions between capparis spinosa extract and phospholipids was performed using FTIR at a frequency of 400- 4000 cm-1. In order to observe shape and morphology of nanoliposomes loaded with capparis spinosa extract by field emission scanning electron microscopy (FESEM), a drop of sample was poured on the laboratory slide, dried at ambient temperature and then, the sample was coated with gold layer using an ion sputtering device. The stability of the samples was evaluated by visual observation of phase separation and the release rate of phenolic compounds encapsulated in nanoliposomes at ambient temperature over a period of 60 days.
Results and Discussion
The amount of phenolic extract was 6.328 mg of GAE/g dry sample. The average particle size (Z- Average) was in the range of 95.05 to 164.25 nm. Increasing the cholesterol concentration resulted in enhancement of particle size of nanoliposomes. The particle size distribution was in an acceptable range of 0.3 to 0.5 (PI 0.5). The PI of the cholesterol-free nanoliposomes was maximum and significantly higher than that of the others. Addition of cholesterol increased zeta potential from -60.40 to -68.55. Higher zeta potential values indicate a higher and long term stability of the particles. Also, cholesterol led to an increase of encapsulation efficiency (EE). The stability of phenolic compounds loaded in nanoliposomes was affected by cholesterol during storage time via reducing fluidity and permeability of liposomal membrane. Presence of cholesterol also inhibited the membrane rupture and any changes into it. Results of FTIR showed interactions between wall constituents of nanoliposome and capparis spinosa extract, and confirmed successful loading of the extract within nanoliposomes. Images of FESEM were in agreement with DLS results regarding particle size and particle size distribution.
Conclusion
This study indicate that the nanoliposomes have potential applications in improvement of the shelf life of nutraceuticals, stability of cosmetic materials and drug delivery systems. The phenolic compounds of encapsulated extract showed good stability within two months of storage at room temperature. The results showed that the problem of instability of phenolic compounds, which leads to their limited commercial application, can be solved by encapsulation.
Food Biotechnology
Rezvan Shaddel; Safoura Akbari-Alavijeh
Abstract
[1]Introduction: Today, the incidence of non-communicable and emerging diseases is increasing due to lifestyle changes, reduced mobility and changing dietary patterns. Some clinical evidences in simulated samples and real cases show that some compounds and plant extracts have a significant effect on ...
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[1]Introduction: Today, the incidence of non-communicable and emerging diseases is increasing due to lifestyle changes, reduced mobility and changing dietary patterns. Some clinical evidences in simulated samples and real cases show that some compounds and plant extracts have a significant effect on the prevention and even treatment of these diseases. On the other hand, due to the structural and functional diversity of plant polysaccharides, there is a great tendency among researchers to find new polysaccharides in different sources with new functional and bioactive properties. Despite extensive studies in this field, no study has been done on the extraction of polysaccharide compounds with prebiotic properties from green almond hull as one of the agricultural wastes. Therefore, the purpose of this study was to introduce a new type of synbiotic compound to balance clone microbiota and promote consumer health. Materials and methods: In this study, after extraction of water-soluble almond hull polysaccharides (AHP) by hot water extraction and precipitation with alcohol, the chemical analysis was done. To investigate the chemical composition of AHP, phenol sulfuric acid test was used to measure total sugar and Bradford test was used to measure protein. The amount of fat and ash in the sample was measured using standard methods (AOAC, 2005) and (AOAC, 2000), respectively. The amount of uronic acid of AHP was measured by calorimetry using metahydroxyphenyl at a wavelength of 520 nm. The content of AHP phenolic compounds was investigated by Folin Siocalcu calorimetric method. Fourier transform infrared (FT-IR) was also used to identify the functional groups and the anomeric status of AHP components. The prebiotic effect of this compound was also tested by digestion resistance and also by growth stimulation of the probiotic strain of Lactobacillus casei ATCC 393 in vitro for the first time. Results and discussion: Chemical analysis showed that AHP is a heteropolysaccharide consisting of 86.30% w/w of total sugar, 5.10% w/w protein and 3.21% w/w uronic acid. FT-IR analysis also confirmed the chemical structure of AHP as a heteropolysaccharide. The results of digestion resistance showed that 91.24% of AHP can remain stable and undecomposed after the stages of gastrointestinal digestion, while this rate was 74.94% for inulin as a commercial prebiotic. The second prebiotic property of AHP investigated in this study was the stimulation the growth of Lactobacillus casei ATCC 393 as probiotic in sugar-free MRS-based culture media and the results showed that AHP compared to inulin significantly increased the survival of Lactobacillus casei ATCC 393 (p <0.01). The proliferation index in media containing AHP and inulin showed a significant difference and AHP stimulated the growth of Lactobacillus casei ATCC393 significantly more than inulin (p <0.01). Therefore, to design a synbiotic product, if AHP is used as a prebiotic, the probiotic strain of Lactobacillus casei ATCC 393 would be a good choice.Considering the annual production of thousands of tons of almond green hull waste in Iran and the concerns related to environmental problems caused by its accumulation, the introduction of industrially feasible and economically justified methods to produce value-added products from this agricultural waste seems essential. In the present study, polysaccharides extracted from almond green hull by hot water extraction and alcohol precipitation, which is an economically feasible method and can be implemented on an industrial scale, were introduced as a useful compound. In vitro studies also used culture medium containing AHP as a commercial prebiotic in comparison with culture medium containing inulin. The results showed that this compound has a good resistance to digestive conditions in the gastrointestinal tract compared to inulin. The compound was also able to stimulate the growth of the probiotic Lactobacillus casei ATCC 393 in culture medium. In general, in this study, a new synbiotic compound including Lactobacillus casei ATCC 393 and AHP was introduced as a health beneficial food additive.
