Food Chemistry
Hamed Saberian; Vahid Pasban
Abstract
[1]Introduction: Anthocyanins are one of the most important of food colorants, which are found in many fruits, flowers, and vegetables, and have been used as natural pigments in commercial foods and beverage products due to their desirable colors and potential nutritional benefits. Saffron (Crocus sativus) ...
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[1]Introduction: Anthocyanins are one of the most important of food colorants, which are found in many fruits, flowers, and vegetables, and have been used as natural pigments in commercial foods and beverage products due to their desirable colors and potential nutritional benefits. Saffron (Crocus sativus) is the most expensive spice of the world and an average 86.4% of wet weight or 96.4% of dry weight of saffron flowers is related to petals. Saffron petals usually do not have a commercial value but contain large amounts of anthocyanins, flavonoids and glycosides. Thus, these petals can be a good source of natural dyes applicable in pharmaceuticals, confectionery, and soft drinks. However, anthocyanins are readily unstable compounds with exposure to oxygen, pH, temperature, enzyme, light, as well as surrounding components, which reduces food color and quality. Losses of anthocyanins occur during juice processing and storage, and methods are needed to prevent these losses. Up to now, various methods including the encapsulation and the co-pigmentation have been tried to intensify the stability of anthocyanins. The co-pigmentation based on the molecular interactions, has been shown to be an efficient way to stabilize anthocyanins. The addition of organic acids, flavonoids, alkaloids, polysaccharides, proteins, etc. as a co-pigment, can improve the stability, and change the bioactivity of anthocyanins. Encapsulation of anthocyanins by alpha and beta cyclodextrins is a potential treatment that could d anthocyanin losses. Anthocyanins can form inclusion complexes with cyclodextrin molecules, which may protect anthocyanins from hydration and polymerization reactions. Therefore, saffron petal is a potential resource of anthocyanin in Iran. Low thermal stability of the anthocyanins caused a tendency to the synthetic colorants. Therefore, the main goal of this research was to investigate the effect of cyclodextrins and co-pigmentation on the anthocyanin extract of saffron petal during heat treatment. Materials and Methods: Anthocyanin extract of saffron petal was extracted by 50% acidic ethanol solution at ambient temperature. Acidified extract was concentrated by a rotary evaporator at 40˚C up to 9 percent concentration of solid materials. Different concentrations of alpha and beta cyclodextrin (10, 25, 50, 75 and 100 mole alpha or beta cyclodextrin to one mole anthocyanin) and also, different co-pigments such as gallic acid (at two molar ratio of 50:1 and 100:1of galic acid/anthocyanin), ferulic acid (at two molar ratio of 50:1 and 100:1of ferulic acid/anthocyanin), quercetin (at two molar ratio of 2.5:1 and 5:1 of quercetin/anthocyanin) and rutin (at two molar ratio of 10:1 and 25:1 of rutin/anthocyanin) were used to study the thermal stability of anthocyanin. Furthermore, the hydroalcoholic extract of rosehip was prepared and concentrated thereby, the rosehip extract (at two molar ratio of 50:1 and 100:1gallic acid equivalent/anthocyanin) was used as a co-pigment. Total anthocyanin content was measured using differential pH method and reported based on mg of cyanidin 3-glucoside per 100 ml the model drink. a* value was measured by Hunter Lab. Model drink (20 mM acid citric buffer in pH of 3) containing 0.01 % CaCl2 and anthocyanin extract was prepared. Prepared model drinks were heated at 90 °C during 0, 15, 30, 45, 60, 90 and 120 min and then, were cooled up to room temperature. Half time of anthocyanin was calculated and the mentioned treatments were investigated to evaluate the stability of the different compounds. Results and Discussion: The results indicated that alpha cyclodextrin at molar ratio of 50:1 (alpha cyclodextrin to anthocyanin) hadn’t any significant effect on the anthocyanin stability but beta cyclodextrin at molar ratio of 50:1 increased the colorant stability, which can be due to the smaller cavity of alpha cyclodextrin rather than beta cyclodextrin that lead to the lower interaction between alpha cyclodextrin and anthocyanin. Although, phenolic co-pigments hadn’t any significant effect on the anthocyanin stability of the model drink but the rosehip extract at two molar ratios of 50:1 and 100: 1 increased the anthocyanin retention. Total phenolic content of rosehip extract was 14.56 g gallic acid equivalent per liter of the extract and total flavonoid content was 365 mg quercetin equivalent per liter of the extract. According to the studies and our results about total phenol and flavonoid content, the increased retention of the anthocyanin can be related to the variety of the phenolic and flavonoid compounds of the rosehip extract. Therefore, beta cyclodextrin as a trapping agent and rosehip extract as a co-pigment, can increase the anthocyanin stability of the saffron petal during heat treatment.
Parvin Sharayei; Hossein Chaji
Abstract
Introduction: Saffron (Crocus sativus) is the most expensive kind of spice in the world while around 400 tons of saffron are estimated to be produced in the current Iranian year (March 2016-17) from 90,000 hectares of land under saffron cultivation across the country. But, high share of producing saffron ...
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Introduction: Saffron (Crocus sativus) is the most expensive kind of spice in the world while around 400 tons of saffron are estimated to be produced in the current Iranian year (March 2016-17) from 90,000 hectares of land under saffron cultivation across the country. But, high share of producing saffron is exclusively dedicated to produce and dry saffron stigma as whereas their violet color petals are mostly ignored and disposed. Saffron petal is one of the most economical sources of anthocyanin pigments. Attractive colour, functional properties and antioxidant properties of anthocyanins can make them a good substitute for synthetic pigments in the food industry. But, due to high moisture content of petals, 96.36% db, they must be dehydrated immediately to prevent the decay. In the meanwhile, the drying conditions are also too critical to petal sensitive compounds while the method of drying along with drying period and the amount of energy consumed, obviously play a significant role on price and quality of the final product.
Materials and methods: In this study, the optimization of the thin layer drying conditions of saffron petal was investigated using response surface methodology (RSM) and Face Centered Experimental Design (FCED) in order to designate the empirical expriments. Saffron petals were dried at different temperatures (40, 50 and 60◦C) and air velocities (0.7, 1.4 and 2.1 m.s-1) in a thin layer dryer and quantitative and qualitative characteristics of saffron petals (color )L: brightness; a: red – green; and b: blue-yellow, total phenolic compounds (TPC), total anthocyanin components (TAC), scavenging activity of DPPH (RSA), ferric reducing-antioxidant power (FRAP) and minimized 50% of radical-scavenging activity (IC50) contents) were invetigated.
Results & discussions: Maintaining the quality of final dried product as high as possible is a major concern while it is an important aspect to consider for use of phenolic compounds and anthocyanins as antioxidants and colorants in food industry. The results showed that the total phenolic compounds (TPC) and total anthocyanin content (TAC) had a remarkable increase with temperature rise from 40 to 50◦C while more temperature increase brought about sharp drops. But, an increasing trend of variations is observed in parallel with increases in velocity of drying air for each temperature. The rise in anthocyanin and phenolic content is more attributed to much significant reduction in drying duration from 40 to 50◦C in comparison with 50 to 60◦C. It was also observed that total antioxidant activity of dried saffron petals showed the same response as TPC and TAC to temperature rise from 40 to 50◦C. Such behaviour could be explained by the findings of other researchers in which the antioxidant activity has high correlation with anthocyanin content and total phenolic composition of food materials. As a complementary, it can be mentioned that polyphenols in an intermediate stage of oxidation have greater antioxidant power than initially even though this is temporary; furthermore high temperature stabilization procedures may lead to the formation of new compounds with higher antioxidant activity. This is essentially the case of the Maillard reaction, which creates various Maillard reaction products, with markedly higher antioxidant power.
Conclusion: Generally, according to Derringer’s desired function approach, the optimal conditions were 50◦C and 1.4 m.s-1.The experimental values agreed with those predicted values. At this optimum condition, the TPC, TAC, DPPH, FRAP, and a value of the dried saffron petal were found to be 46.39 mg/ g ,1205.58 mg/l, 52.97%, 1276.52 µmol Fe2+/l, and 11.13, respectively. The experimental values were in a good agreement with the predicted values.
Mohammad Farhadi Chitgar; Mehdi Varidi; Mohammad Javad Varidi; Ahmad Balandari
Abstract
Introduction: Extensive researches into native plants as a source of functional food have been conducted over the resent years. Meanwhile, barberry has been utilized as one of the main medicinal plants in Iran and many other countries, from the past decades. Currently, it has been known pharmaceutical ...
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Introduction: Extensive researches into native plants as a source of functional food have been conducted over the resent years. Meanwhile, barberry has been utilized as one of the main medicinal plants in Iran and many other countries, from the past decades. Currently, it has been known pharmaceutical active ingredients like berberin have wide application in pharmaceutical industry. The genus of Berberis includes about 450–500 species of deciduous or evergreen shrubs in which four species B.integerrima, B.crataegina, B.vulgaris and B.orthobotrys are found in Iran. Iran is the first largest producer of barberry (B.vulgaris) in the world. Apart from that, other species in different parts of Iran grow in wild conditions. B. Integerrima is a thorny shrub with fragile branches to a height of 1 to 3 meters. Its fruits are small and red with a mild sour taste. There are 1-4 small oblong seeds inside. The changes in this species are important and can produce hybrid with other species. B. Integerrima fruits are consumed fresh or used in the preparation of traditional foods. Barberry fruit, which contains large amount of anthocyanins, can be used as an alternative to synthetic colorants. In addition, aqueous extract of barberry has beneficial effects on both cardiovascular and neural system suggesting a potential use for treatment of hypertension, tachycardia and some neuronal disorders, such as epilepsy and convulsion. The physical properties of barberry genotype are important to design the equipment for sorting, transportation, separation, processing and packaging. Identification of the chemical characteristics of Berberis genotype can lead in using them in the pharmaceutical or food industries. Therefore, in order to introduce these native species, physicochemical characteristics of three wild barberries were evaluatedMaterials and method:Three native seed genotypes from Semnan province were manually collected from Research Institute of Food Science and Technology (Mashhad). The harvested fruits were instantly stored inside ice box to minimize damages and transported to the laboratory. Over ripened and damaged fruits were separated. Some physical properties (size, geometric mean diameter, sphericity, area, mass and the weight ratio of seeds to fruit) of fruits were determined using 100 repetitions at the natural moisture content of fruits. Chemical properties of samples were determined as follows: total anthocyanin content by the pH differential, total phenolic content by modified Folin–Ciocalteu method, mineral elements amounts such as Potassium(K), Sodium (Na) and Calcium (Ca) by Flame Photometer and microelements (Fe, Cu, Mg, and Zn) by Atomic Absorption Spectrophotometer, Moisture, crude oil, crude protein, ash, reducing sugar, water-soluble extract, pH and acidity were determined according to Indrayan et al,1989 and Iranian National Standard No. 2685. All experiments (except physical properties) were repeated at least three times and results were expressed as mean ± SD. The significant differences between mean values of juice samples were determined by analysis of variance (one way-ANOVA) using Duncan’s test at a significance level of p< 0.05. Data analysis was performed using the SPSS 19.0 software.Results and Discussion: Results showed that in physical properties such as, fruit length there was statistically difference between genotypes. The number of seeds in the three genotypes varied between 1 and 4 numbers. The weight ratio of seeds to fruit was 11.88%, 10.84% and 10.68 in Noshin, Negarin and Parchin genotypes, respectively. All three genotypes contained high amount of protein, total carbohydrate, fat and ash (3.82-5.255%, 21.68-23.97%, 2.04-2.70% and 0.94-1.27%). Noshin contained the highest reduced sugar (8.03±0.222). So, it is sweeter taste than others. In accordance with result, the amount of anthocyanins (950.17-3927.60mg/L) and total phenol (9.75-12.35gr/L) were higher than these fruits in comparison to the other fruits like mulberry and blueberry that represents the health benefits of these wild plants. All the three genotype emerged as good source of minerals, especially K, Ca, Mg and Zn.
Roksaneh Rouhani; Soudabeh Einafshar; Reihaneh Ahmadzadeh Ghavidel
Abstract
Sepals and petals are byproducts from saffron production process that waste without any use in Iran. These byproducts containing a lot of anthocyanin and natural antioxidants.The aim of this study is determine efficiency of extraction and measurement of antioxidant activity and anthocyanin pigments of ...
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Sepals and petals are byproducts from saffron production process that waste without any use in Iran. These byproducts containing a lot of anthocyanin and natural antioxidants.The aim of this study is determine efficiency of extraction and measurement of antioxidant activity and anthocyanin pigments of pollen and anther of saffron flower ,using mixed solvent of ethanol and hydrochloridic acid 1.5 N (85:15) by ultrasonic waves. Therefore, the time factors (5, 15, 25 minutes) and sound intensity (20, 60 and 100%) were usedThe results showed that the most efficient extraction of samples (54/48%) was extracted in 15 minute and 100% of sound intensity, and the maximum measure of anthocyanin compounds (48.83 mg/ml), total phenolic compounds (36.54 mg/ml), power of reviving the anti-radical DPPH activity of the extracts (335.7 mg/ml) and the power of scavenging Fe III (431.1µmol/lit Fe III), the best sample in all of the exams was extracted in 10 minutes and 100% of sound intensity. So, the optimized situation for extraction of anthocyanin compounds by ultrasound waves was time 15 min and 100% about sound intensity.
