固态(膏状)番茄红素产品稳定性研究

番茄红素油树脂是从西瓜、番茄及番茄制品等中分离出来的含有番茄红素的混合物。由于分子中有 11个共轭双键及 2个非共轭双键 ,因而具有很强的抗氧化能力 ,在贮存过程中极易发生顺反异构化及氧化破坏 ,进而丧失生理活性 ,甚至产生有害成分。文中研究了固态 (膏状 )番茄红素在不同条件下存放时被氧化破坏或发生顺反异构化的规律 ,依据SAS软件的处理结果给出了其残留率计算公式 ,并提出了适宜的产品存放条件     

Lycopene degradation and isomerization in tomato dehydration

Lycopene is an important nutrient, since it appears to provide protection against a broad range of epithelial cancers. Tomatoes and tomato products are the major source of lycopene, and are considered to be an important source of carotenoids in the human diet. Biodegradation of lycopene not only affects the attractive color of the final products, but also their nutritive value. The main cause of lycopene degradation in tomato dehydration is isomerization and oxidation. The objectives of this study were to determine the retention of total lycopene and isomerization in different dehydration methods, and to optimize processing technology for the retention of lycopene biological potency in the tomato products. Experiments were carried out to compare the effect of osmotic treatment, vacuum-drying, air-drying and their combination on the retention of lycopene bioactivity. Firstly a skin treatment was applied to the tomatoes, following an osmotic treatment at 25°C in 65°Brix sucrose solution for 4 h, then vacuum-drying at 55°C for 4–8 h, or air-drying at 95°C for 6–10 h. In the fresh tomato samples, lycopene content is 75.5 μg/100 g on dry weight basis. Lycopene occurs in nature primarily in the more stable all-trans form. A significant increase in the cis-isomers with simultaneous decrease in the all-trans isomers can be observed in the dehydrated tomato samples in the different dehydration methods. The cis-isomers increased with temperature and processing time. In the osmotic treatment, the predominating mechanism is isomerization of lycopene. Since the total lycopene content remained essentially constant, but the distribution of trans- and cis-isomers changed. In the air-drying processing, isomerization and oxidation (autoxidation) as two strong factors affected simultaneously the decrease of total lycopene content, distribution of trans-and cis-isomers, and biological potency. A possible explanation of this result is that sugar enters the tomato matrix and strengthen the binding force on lycopene in the tomato matrix. Osmotic solution (sugar) remaining on the surface layer of the tomato prevents oxygen from penetrating and oxidizing lycopene. The osmotic treatment could reduce lycopene losses in comparison with other dehydration methods.     

番茄红素油树脂中脂肪酸组成的分析

番茄红素油树脂是以番茄皮渣为原料、以非极性溶剂为介质来进行抽提而得到的油溶性成分的混合物,其中除含有番茄红素外,还含有一定数量油脂及脂肪酸,维生素E、甾醇及磷脂等类脂性成分.本研究通过对皂化后所得脂肪酸经AMP衍生化所产生衍生产物的GC／MS法,对其中的脂肪酸组成及其含量进行了分析.结果表明,番茄红素油树脂中脂肪酸组成包括14∶0,16∶0,18∶0,18∶1,18∶2,18∶3等几种,以饱和脂肪酸为主,约占脂肪酸总量的75%,而不饱和脂肪酸仅占25%,并且所有脂肪酸的碳链均较短.     

Comparison of lycopene stability in water- and oil-based food model systems under thermal- and light-irradiation treatments

Lycopene can undergo degradation via isomerization and oxidation during processing and storage. These degradative reactions affect its bioactivity and health benefit functionality. Degradation kinetics and isomerization of lycopene in water- and oil-based tomato model systems were investigated as a function of thermal treatments and light irradiation. Results showed that 80 and 100 °C heating favoured the stability of lycopene in oil-based tomato products. The high heating temperatures (120 and 140 °C) increased isomerization of lycopene and resulting in degradation of total lycopene and cis-isomers in both water- and oil-based tomato products. However, the levels of degradation of total lycopene contents and cis-isomers were greater in water-based samples than in oil-based model systems under different treatments. Heat and light both promoted lycopene isomerization of the all-trans form to the cis-isomers and further oxidation of cis-isomers. The major effect of thermal degradation and photosensitized oxidation was a significant decrease in the total lycopene content, especially the content of cis-isomers. These research results could be useful in assisting industry to improve processing technology and to improve the nutritional value and health-benefits of tomato-based foods.     

KINETICS OF LYCOPENE DEGRADATION IN TOMATO PUREE BY HEAT AND LIGHT IRRADIATION

Lycopene as a natural antioxidant may provide protection against a broad range of epithelial cancers. Tomatoes and tomato‐based food products are a major source of lycopene compounds. Thermal processing is the main procedure in tomato puree production. Heat and light induces lycopene oxidation and isomerization of the all‐trans form to the cis form. The level of cis‐isomers increases as treatment time increases but only for a short period during the beginning of the treatment. The major effect of thermal processing was a significant decrease in the total lycopene content. Lycopene is relatively stable if heated at temperatures below 100C, but the duration of heating must be taken into consideration. The kinetics of lycopene degradation was analyzed. A shorter period of time of heating and less light irradiation in processing and storage would reduce lycopene degradation to a great extent.     

Characterisation of oleoresins extracted from tomato waste by liquid and supercritical carbon dioxide

Tomato waste is characterised by high amounts of bioactive compounds, such as carotenoids, polyphenols and essential fatty acids. In this work, oleoresins were produced from tomato waste (skins + seeds) and skins using carbon dioxide under liquid and supercritical conditions. The use of ethanol as a co-solvent was also evaluated. Compositions of the oleoresins were analysed and compared to oleoresin obtained by means of an organic solvent, which was used as the control. Oleoresin extraction from the waste by liquid and supercritical CO₂ provided the highest yields (12.5%–12.9%). The extracts obtained from the skins with supercritical CO₂ without ethanol had the highest content of α- and γ-tocopherols (80 and 575 mg/100 g oleoresin, respectively), while lycopene and β-carotene were found at 205 and 75 mg/100 g oleoresin, respectively. The highest quantity of polyphenols (9305 mg GAE/100 g oleoresin) was found in the oleoresin extracted from skin by supercritical CO₂ with ethanol. All oleoresins were characterised by a high antioxidant activity, which improved with the synergy of carotenoids, tocopherols and polyphenols.     

Optimisation of biological and physical parameters for lycopene supercritical CO2 extraction from ordinary and high‐pigment tomato cultivars

BACKGROUND: Lycopene is used for several industrial applications. Supercritical CO₂ (SC‐CO₂) extraction from red‐ripe tomato fruits is an excellent technique to replace the use of harmful solvents. In this study, starting from red‐ripe tomatoes of ordinary and high‐lycopene cultivars, the effect of different agronomical and technical aspects on lycopene content, stability and yield was evaluated throughout the production process from fresh tomatoes to the final SC‐CO₂‐extracted oleoresin containing lycopene. RESULTS: Red‐ripe tomato cultivars differed in their lycopene content. Irrigation excess or deficit caused an increase in the amount of lycopene in the fruits. Fresh tomatoes were processed into a lyophilised matrix suitable for SC‐CO₂ extraction, which could be stored for more than 6 months at ? 20 °C without lycopene loss. Under the optimal extraction conditions, efficiencies of up to 80% were achieved, but the recovery of lycopene in the extracted oleoresin was very low (～24%). Co‐extraction of the tomato matrix mixed with a lipid co‐matrix allowed the recovery of ～90% of lycopene in the oleoresin. Using the high‐lycopene cultivars, the yield of total extracted lycopene increased by ～60% with respect to the ordinary cultivars. Lipids and other biologically active molecules were present in the oleoresin. CONCLUSION: A method for extracting, from a tomato matrix, a natural and solvent‐free oleoresin containing lycopene dissolved in a highly unsaturated vegetable oil has been described. The oleoresin represents an excellent product for testing on cancer and cardiovascular disease prevention. Copyright © 2010 Society of Chemical Industry     

Effects of Cooking Conditions on the Lycopene Content in Tomatoes

ABSTRACT:  Raw tomato contains a high level of lycopene, which has been reported to have many important health benefits. However, information on the changes of the lycopene content in tomato during cooking is limited. In this study, the lycopene content in raw and thermally processed (baked, microwaved, and fried) tomato slurries was investigated and analyzed using a high-performance liquid chromatography (HPLC) method. In the thermal stability study using a pure lycopene standard, 50% of lycopene was degraded at 100 °C after 60 min, 125 °C after 20 min, and 150 °C after less than 10 min. Only 64.1% and 51.5% lycopene was retained when the tomato slurry was baked at 177 °C and 218 °C for 15 min, respectively. At these temperatures, only 37.3% and 25.1% of lycopene was retained after baking for 45 min. In 1 min of the high power of microwave heating, 64.4% of lycopene still remained. However, more degradation of lycopene in the slurry was found in the frying study. Only 36.6% and 35.5% of lycopene was retained after frying at 145 and 165 °C for 1 min, respectively.     

Lycopene Stability in Tomato Powders

The chemical stability of lycopene in 2 commercial tomato powders was evaluated during storage. Liquid chromatography and spectral analysis were used to determine lycopene loss and the formation of cis isomers and degradation products. Tomato powder products were stored at 6 and 45 °C or under fluorescent light for up to 6 wk. Several lycopene degradation products were tentatively identified in the initial and stored powders. After 6 wk at 45 °C, 60% of the lycopene was degraded. At lower storage temperatures the losses were about 30% after 6 wk. Mechanisms of loss appear to be both isomerization and oxidation.     

Study on lycopene and antioxidant contents variations in tomatoes under air-drying process

ABSTRACT:  Effects of factors such as tomato cultivars, drying temperatures (40, 80, and 120 °C), and drying time (0 to 240 min) on tomato lycopene and the major antioxidant contents (MACs, herein as the sum of total phenolics and total flavonoids) during an air-drying process were investigated. The results showed that lycopene contents increased under all the drying temperatures during the first 60 min. However, the red tomato cultivars, that is, HR, SN, and TTL, exhibited a significant decrease in lycopene contents under 120 °C after drying for 75 min. According to the experimental data, an MAC threshold value of 500 mg/100 g dry matter of tomato is proposed. When the MAC is lower than this value during air-drying, lycopene contents in all tomato cultivars would drop rapidly. In addition, the tomatoes in yellow color group, containing more MACs initially and retaining more MACs under air-drying at 40 to 80 °C, are proposed to be the proper tomato cultivars for thermal processing.     

Degradation of Lycopene, α-Carotene, and β-Carotene During Lipid Peroxidation

The stability and antioxidant effectiveness of lycopene, a-carotene, and b-carotene were compared during oxidation of methyl linoleate at 37 and 60 °C. Two carotene concentrations, 80 or 160 mg/g of methyl linoleate, were used to determine a concentration effect. At 37 °C, the degradation rates were: lycopene > β-carotene > α-carotene. Lycopene and α-carotene inhibited hydroperoxide formation, lycopene being the more effective antioxidant. β-Carotene inhibited hydroperoxide formation at the lower concentration but did not show an antioxidant effect at the higher concentration. At 60 °C, the carotenes degraded 6 to 8 times faster than at 37 °C and did not show an antioxidant effect. BHT or α-tocopherol effectively suppressed the hydroperoxide formation and degradation of the carotenes.     

番茄红素在有机溶剂中的异构化

采用C 3 0柱 (YMCTM CarotenoidS 5 4 6mm× 2 5 0mm )对番茄红素顺反异构体进行分离测定 ,对番茄红素在不同温度及不同有机溶剂中的异构化程度进行了比较。结果表明 ,在以甲醇 甲基叔丁基醚 乙酸乙酯 (体积比为 5 0∶40∶1 0 )为流动相 ,流速为 1 5mL/min ,温度 2 5℃条件下 ,可将番茄红素全反式与顺式异构体进行分离。番茄红素在不同溶剂中顺反异构化程度不同 ,二氯甲烷 >丙酮 >四氢呋喃 >乙酸乙酯 >正己烷 ;异构化程度与温度有关 ,1 5℃时异构化程度高于 4℃时     

Lycopene in tomatoes: chemical and physical properties affected by food processing

Lycopene is the pigment principally responsible for the characteristic deep-red color of ripe tomato fruits and tomato products. It has attracted attention due to its biological and physicochemical properties, especially related to its effects as a natural antioxidant. Although it has no provitamin A activity, lycopene does exhibit a physical quenching rate constant with singlet oxygen almost twice as high as that of beta-carotene. This makes its presence in the diet of considerable interest. Increasing clinical evidence supports the role of lycopene as a micronutrient with important health benefits, because it appears to provide protection against a broad range of epithelial cancers. Tomatoes and related tomato products are the major source of lycopene compounds, and are also considered an important source of carotenoids in the human diet. Undesirable degradation of lycopene not only affects the sensory quality of the final products, but also the health benefit of tomato-based foods for the human body. Lycopene in fresh tomato fruits occurs essentially in the all-trans configuration. The main causes of tomato lycopene degradation during processing are isomerization and oxidation. Isomerization converts all-trans isomers to cis-isomers due to additional energy input and results in an unstable, energy-rich station. Determination of the degree of lycopene isomerization during processing would provide a measure of the potential health benefits of tomato-based foods. Thermal processing (bleaching, retorting, and freezing processes) generally cause some loss of lycopene in tomato-based foods. Heat induces isomerization of the all-trans to cis forms. The cis-isomers increase with temperature and processing time. In general, dehydrated and powdered tomatoes have poor lycopene stability unless carefully processed and promptly placed in a hermetically sealed and inert atmosphere for storage. A significant increase in the cis-isomers with a simultaneous decrease in the all-trans isomers can be observed in the dehydrated tomato samples using the different dehydration methods. Frozen foods and heat-sterilized foods exhibit excellent lycopene stability throughout their normal temperature storage shelf life. Lycopene bioavailability (absorption) can be influenced by many factors. The bioavailability of cis-isomers in food is higher than that of all-trans isomers. Lycopene bioavailability in processed tomato products is higher than in unprocessed fresh tomatoes. The composition and structure of the food also have an impact on the bioavailability of lycopene and may affect the release of lycopene from the tomato tissue matrix. Food processing may improve lycopene bioavailability by breaking down cell walls, which weakens the bonding forces between lycopene and tissue matrix, thus making lycopene more accessible and enhancing the cis-isomerization. More information on lycopene bioavailability, however, is needed. The pharmacokinetic properties of lycopene remain particularly poorly understood. Further research on the bioavalability, pharmacology, biochemistry, and physiology must be done to reveal the mechanism of lycopene in human diet, and the in vivo metabolism of lycopene. Consumer demand for healthy food products provides an opportunity to develop lycopene-rich food as new functional foods, as well as food-grade and pharmaceutical-grade lycopene as new nutraceutical products. An industrial scale, environmentally friendly lycopene extraction and purification procedure with minimal loss of bioactivities is highly desirable for the foods, feed, cosmetic, and pharmaceutical industries. High-quality lycopene products that meet food safety regulations will offer potential benefits to the food industry.     

Degradation of Lycopene and β‐carotene in Model Systems and in Lyophilized Guava during Ambient Storage: Kinetics,Structure, and Matrix Effects

ABSTRACT: Being highly unsaturated, carotenoids are susceptible to isomerization and oxidation during the processing and storage of food. In the present study, the degradation of acyclic lycopene and dicyclic β‐carotene in low‐moisture and aqueous model systems, as well as in lyophilized guava, during storage at ambient temperature, in the absence or presence of light, was investigated. Both carotenoids followed first order kinetics under the various conditions investigated. Lycopene degraded much faster than β‐carotene in all the model systems. In a comparison of lycopene isolated from guava, tomato, and watermelon, greater losses were observed with lycopene from tomato. Since the model system was identical in the 3 cases, these results indicated that other compounds from the food sources, co‐extracted with lycopene, might have influenced the oxidation. Light consistently and strongly promoted degradation under all conditions studied. The susceptibility of lycopene to degradation was much less in lyophilized guava than in the model systems, showing the marked protective influence of the food matrix. Loss of β‐carotene, found at a concentration of about 18 times lower than lycopene, was only slightly lower than that of lycopene in lyophilized guava, indicating that the effect of matrix and/or the initial concentration overshadowed the structural influence.     

大鼠对番茄红素表观消化率的研究

番茄红素的研究报道主要集中在番茄红素的提取和制备、基础及药理研究等方面,而涉及番茄红素的体内消化吸收和剂量安全性方面的研究报道则相对较少。采用番茄红素含量为0．006％番茄酱和浓度分别为2％、4％和6％的番茄红素油树脂对大鼠进行灌胃试验,收集其粪便和尿液,对其中的番茄红素进行萃取,并根据国际标准检测其中番茄红素的含量,最终计算出消化率为99％以上。     

Tomato pulp as source for the production of lycopene powder containing high proportion of cis-isomers

Cis-isomers of lycopene has been demonstrated to possess higher biological activity than its all-trans form. The objectives of this study were to compare the extraction efficiency and degree of isomerization of lycopene by employing supercritical carbon dioxide (SCD) and solvents, as well as process the lycopene extract into powder containing high proportion of cis-isomers from tomato pulp as source. Results showed that a high yield of lycopene was achieved by SCD at 350 bar and 70 °C, with cis-isomers making up 41.4% of total lycopene. However, with temperature at 80 and 90 °C, the maximum isomerization was accomplished, and cis-lycopene constituted 51.0 and 53.8% of total lycopene, respectively. For solvent extraction, the highest yield of all-trans-lycopene was attained by ethanol–hexane (4/3 v/v) at 25 and 50 °C, whereas the maximum isomerization (47.0% cis-lycopene) occurred at 75 °C. A powder product containing 34.5% cis-isomers of lycopene was obtained by spray-drying, and the total amount of lycopene in spray-dried powder was much greater than that in freeze-dried powder. The maximum yield of lycopene in the powder product could be obtained through processing by adding sodium alginate to the eluate directly after SCD extraction and open-column chromatography with formation of 41.4% cis-lycopene. The method developed in this study may be used for possible commercial production of highly active lycopene powder.     

Influence of extraction with ethanol or ethyl acetate on the yield of lycopene, β-carotene,phytoene and phytofluene from tomato peel powder

This study evaluated the extraction yield of the food grade solvents ethanol and ethyl acetate by extracting lycopene, β-carotene, phytoene and phytofluene from tomato peel powder at varying heating intensities, and the influence of the solvent and heating intensity on carotenoids isomerization and degradation during extraction. The heat treatments assayed were 25, 35, 50 and 60 °C which were applied for periods of 5, 10, 20, 30 or 40 min. The carotenoid yield was higher in the extractions with ethanol than with ethyl acetate. In general, the temperature increase caused an increase in the carotenoid concentrations; however in the extractions performed with ethanol at 60 °C, the yield of (all-E)-lycopene and their (Z)-isomers was lower than at 50 °C. This could indicate that a great isomerization is produced in the high temperature extractions with ethanol but the oxidative degradation is the predominant reaction. On the contrary, the obtained results in the extractions with ethyl acetate indicate that the isomerization is the predominant reaction.     

Lycopene (Z) – isomers enrichment and separation

(All‐E)‐ Lycopene undergoes geometrical isomerisation into (Z)‐lycopene isomers with thermal treatment. Influence of three isomerisation methods including ethyl acetate reflux, microwave‐assisted reflux and ultrasound/microwave‐assisted reflux, and isolation of (all‐E)‐lycopene from other carotenoids and (Z) lycopene isomers through selective inclusion by deoxycholic acid (3α, 12α dihydroxy‐5βcolan‐24‐oic‐acid, DCA) were investigated. The results showed that microwave and ultrasound/microwave‐assisted reflux were not significantly different at P < 0.05, but both were significantly different (P < 0.05) over refluxing in ethyl acetate, proportion of (Z)‐lycopene isomers reached 54% after refluxing for 5 h. Heterogeneous mixture of isomerised tomato oleoresin containing 54% (Z)‐lycopene isomers and 40% (all‐E)‐lycopene and deoxycholic acid in dichloromethane was incubated at 25 °C for 2 h. Then, the mixture was filtered and from the filtrate 96.6% (Z)‐isomers enriched lycopene was obtained. The processes can be used in the production of enriched (Z)‐lycopene isomers for food supplements and functional food industry as a natural bioactive ingredient.     

Modeling Lycopene Degradation and Isomerization in the Presence of Lipids

The kinetics of thermally induced degradation and isomerization of lycopene in olive oil, fish oil, and an olive oil/tomato emulsion were studied in detail. Special attention was paid to the isomerization reactions using a multi-response modeling approach. The type of oil had a significant impact on lycopene degradation kinetics, being faster in fish oil compared with olive oil. The estimated kinetic parameters to describe lycopene degradation in olive oil were not significantly different from those in an olive oil/tomato emulsion. The overall Z-isomer formation and elimination in olive oil, fish oil, and olive oil/tomato emulsion was similar. Only the kinetic parameters for 13-Z-lycopene formation differed significantly in the two oils. Although the isomerization rate constants for the emulsion were lower than for olive oil, the isomerization reactions showed similar temperature dependency. This study shows that the kinetics of thermally induced degradation and isomerization of lycopene in oil and in an olive oil/tomato emulsion can be described using the same model. The food system, however, has an influence on the model parameters, especially on the rate constants.     

Effects of Heat Treatment on the Carotenoid and Tocopherol Composition of Tomato

Abstract: The objective of this study was to determine the influence of thermal processing on the assessment of tocopherols and carotenoids, as well as their isomer formation in tomatoes. The sliced tomatoes were heated in an oven at 100, 130, and 160 °C for 5, 10, and 20 min, then freeze‐dried. Freeze‐dried samples were finely ground and the analysis was performed on lyophilized samples. The average concentrations of total lycopene, lutein, β‐carotene, α‐tocopherol, and γ‐tocopherol in fresh tomatoes (in 100 g dry weight) were 21.2, 1.1, 2.7, 8.0, and 2.5 mg, respectively. Oven baking of tomato at 160 °C for 20 min led to a significant increase in the apparent measurement of lycopene, β‐carotene, and α‐tocopherol content by 75%, 81%, and 32%, respectively. Heating induced isomerization of (all‐E) to various (Z) isomers of lycopene, and we found that the total (Z)‐lycopene proportion in the tomatoes increased with longer heating time. (All‐E)‐lycopene constituted 75.4% in fresh tomatoes and decreased to 52.5% in oven‐baked tomatoes (160 °C, 20 min), while (5Z)‐lycopene increased from 9.4% to 17.9% of total lycopene. However, β‐carotene release and isomerization was less influenced by the heat treatment than that of lycopene. These results suggested that thermal processes might break down cell walls and enhance the release of carotenoids and tocopherols from the matrix, as well as increase isomerization of lycopene and β‐carotene.