Supercritical carbon dioxide extraction of lycopene: A review

Lycopene is a powerful antioxidant and potential high-value compound for the nutraceutical and pharmaceutical sectors. Its low solubility in water and high solubility in toxic organic solvents has led to a number of studies being carried out on using supercritical carbon dioxide to extract lycopene, with a majority of the studies focusing on extraction from tomatoes or tomato-derived preparations. Parameters such as temperature, pressure, flow rate, extraction time, sample moisture content and sample particle size influence the yield of lycopene via the exertion of different mechanisms. The use of co-solvents and modifiers can greatly enhance the lycopene yield beyond optimization of the parameters previously mentioned, while the co-extraction method offers a new way of enhancing lycopene yields. The scope of this review covers the effects of various parameters on lycopene extraction by supercritical carbon dioxide.     

Production of frankfurters with tomato powder as a natural additive

This study includes the investigation of chemical properties such as nitrosomyoglobin content, lycopene content, and the oxidation level, and the sensorial properties of frankfurters which have been produced by both reducing the nitrite level and adding tomato powder. All samples have been vacuum packed and stored at +4 °C for 60 days.The pH of the frankfurters produced with tomato powder was reduced, when compared to the samples which did not contain tomato powder. This effect was due to the acidic characteristics of tomato. As the level of nitrite was reduced, the oxidation level of the frankfurters was increased significantly. Addition of 2 g/100 g of tomato powder decreased the level of oxidation; however, 4 g/100 g of tomato powder caused a slight increase when compared to the samples which did not contain tomato powder. According to this result it can be stated that tomato powder retards the oxidation reaction. According to sensorial evaluations, tomato powder improved the consumer acceptability as well. Addition of tomato powder increased the internal and external colour scores, and frankfurters were found to be more acceptable by the panellists. Nitrosomyoglobin (NOMb) content of the samples was decreased along with the decreased level of nitrite, and this, in turn, contributed to the decreased level of redness (a*).     

Apparent solubility of lycopene and β-carotene in supercritical CO2, CO2 + ethanol and CO2 + canola oil using dynamic extraction of tomatoes

Lycopene and β-carotene were extracted from freeze-dried tomatoes (skin + pulp) with pure SC CO₂ and SC CO₂ + 5% w/w co-solvent at 40 °C, 400 bar and flow rates of 0.5 and 1.2 L/min. The apparent solubility of lycopene and β-carotene in the multicomponent complex system was determined from dynamic extraction experiments using a laboratory-scale supercritical extraction system. Solubility of pure lycopene and β-carotene in SC CO₂ (binary system) was reported in the literature to be of the order of 10⁻⁶ mole fraction. The apparent solubility of lycopene extracted from tomatoes with SC CO₂ (multicomponent complex system) under the same conditions was almost one order of magnitude smaller. The apparent solubility obtained using oil as a co-solvent was higher than that obtained with ethanol as a co-solvent or pure SC CO₂. The differences in solubility are mainly due to the polarity of the co-solvent and the impact of the tomato matrix in the multicomponent complex system.     

Effects of organic tomato pulp powder and nitrite level on the physicochemical,textural and sensory properties of pork luncheon roll

Nine treatments of pork luncheon roll produced with three sodium nitrite levels (0, 0.05 and 0.1%) and three tomato pulp powder (TPP) levels (0, 1.5 and 3%) were assessed at three storage times (2, 7 and 14 d). The effects of enrichment with TPP on composition (protein, fat, moisture and ash), pH, colour (CIE L*, a*, b*), nitrosomyoglobin (NOMb) content, lipid oxidation (TBARS), residual nitrite content, total viable count (TVC) texture profile analysis (TPA) and sensory analysis of cooked pork luncheon roll were investigated. Decreasing the level of nitrite increased (p < 0.001) the pH, the NOMb value (p < 0.001), lipid oxidation (p < 0.001) and the residual nitrite content (p < 0.001) and affected the colour of the cooked product. The reduction in nitrites had no effect on the composition and texture of the pork luncheon rolls. Adding TPP reduced (p < 0.001) the pH and increased (p < 0.001) the colour parameters a* and b* of both the raw luncheon roll formulation and the cooked luncheon roll product. TPP, particularly at 3% had a detrimental effect on the texture of pork luncheon rolls by decreasing hardness (p < 0.001), gumminess (p < 0.001) and chewiness (p < 0.001) and increasing cohesiveness (p < 0.001). The TBA value increased (p < 0.01) with the three main factors (nitrite, TPP, day) but was in all cases well below the 2 mg MDA/kg threshold. TVCs for all treatments and storage days were below the TVC limit for this type of cooked product. The pork luncheon roll formulated with 50 mg nitrite and 1.5% TPP had similar or enhanced sensory attributes compared to the luncheon roll containing no TPP and a nitrite level of 100 mg/kg of product.     

Improving the stability of lycopene Z-isomers in isomerised tomato extracts

Tomato-based foods rich in Z-lycopene are potentially more bioavailable and have greater bioefficacy compared to natural tomato products which mainly contain all-E-lycopene. To prepare a stable tomato extract with a high level of Z-lycopene, geometrical isomerisation of lycopene was studied in organic solvents either alone or in the presence of a tomato extract. Interconversion between the isomers was observed in all systems with 13Z-lycopene being the least stable. Heating a tomato extract containing mainly the all-E-isomer in ethyl acetate produced successively 13Z-, 9Z- and 5Z-lycopene. An isomerised tomato oleoresin with a minimal content of the most unstable 13Z-lycopene could be obtained by refluxing tomato oleoresin in ethyl acetate for 1 week. In this isomerised tomato oleoresin, total lycopene and lycopene isomer profiles were shown to remain constant for 1 year at room temperature. Accordingly, this product is a valid source of stable and potentially highly bioavailable lycopene.     

Effect of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility

The influence of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility was investigated. To this purpose, samples were subjected to ultrasound at a frequency and amplitude of 24 kHz and 100 μm, respectively, for increasing lengths of time. Results showed that ultrasound was responsible for loss of tomato cell integrity, as well as a decrease in the degree of pectin esterification. In contrast, rheological measurements showed that ultrasonically treated tomato pulp had greater gel-like properties than an untreated sample. It was inferred that ultrasound promoted the formation of a new network due to hydrogen bonding and hydrophobic interactions among the de-esterified pectin molecules. Such a reinforcement of the tomato pulp structure resulted in a decrease in lycopene in vitro bioaccessibility of the ultrasonically treated tomato pulp, probably due to the fact that the presence of a stronger network may make lycopene less available to the digestion process.     

高配比竹浆口杯原纸的生产实践

口杯原纸广泛用于加工各种环保型一次性餐饮产品.高配比竹浆口杯原纸的研究与生产,对拓宽造纸原料,以竹代木,降低生产成本,提高纸厂经济效益有较大现实意义.本文通过对影响竹浆口杯原纸质量的主要原因进行分析,结合生产实际提出高配比竹浆口杯原纸的工艺控制措施.     

纤维素醚用高黏浆生产工艺研究

对纤维素醚用高黏浆生产工艺进行了研究。探讨了高黏浆制造过程中影响蒸煮、漂白的主要因素。根据客户的使用要求,通过单因素试验及正交试验法,并结合公司实际设备能力,确定了纤维素醚用高黏浆生产工艺参数。利用该生产工艺,生产的纤维素醚用高黏棉浆白度≥85%,黏度≥1800 mL/g。     

调味新品--高钙鸽精生产工艺

报道了高钙鸽精的生产工艺,全面地介绍了全部工艺过程,并提供了重要的技术参数和数据.     

Microstructure and bioaccessibility of different carotenoid species as affected by high pressure homogenisation: A case study on differently coloured tomatoes

The effect of high pressure homogenisation (HPH) on structure (Bostwick consistency, particle size distribution and microstructure) and carotenoid in vitro bioaccessibility of different tomato pulps was investigated. HPH decreased tomato particle size due to matrix disruption and increased product consistency, probably due to the formation of a fibre network. Homogenisation also resulted in a decrease of in vitro bioaccessibility of lycopene, ζ-carotene, and lutein. Such decrease was attributed to the structuring effect of HPH. An inverse relation between tomato consistency and carotenoid in vitro bioaccessibility was found. This dependency was affected by carotenoid species and its localisation within the matrix. It could be observed that one matrix (e.g. (homogenised) red tomato pulp) can contain carotenoids with a very low bioaccessibility (lycopene) as well as carotenoids with a very high bioaccessibility (lutein), indicating that carotenoid bioaccessibility is not solely dependent on the matrix.     

CO2超临界流体代替水作介质铬鞣机理的研究(3)--CO2超临界流体条件下铬鞣初始pH值和温度的优化

利用自制的CO2超临界流体制革设备,考察了CO2超临界流体代替水作介质条件下的铬鞣因素：初始pH值和温度的影响。通过对各实验条件下坯革的收缩温度、铬含量、铬的渗透以及革坯的状态等进行评价鞣制效果,得到了在CO2超临界流体条件下的铬鞣的最佳初始pH值为3．5,最佳鞣制温度为34℃。     

废纸脱墨浆生产线的设计

从介绍新闻纸废纸脱墨浆流程设计开始,到将原新闻纸脱墨浆生产线改造成文化用纸脱墨浆生产线,以及当前规模较大的、用于文化用纸脱墨浆生产线工艺流程及设备排列的特点、设备选型的方法供读者参考。     

含机械浆纸张的掉毛掉粉成分分析及处理方法

分析了含机械浆纸张纸粉的主要成分为纤维束、阔叶木导管、填料,细小纤维等,并提出降低纤维束、阔叶木导管含量,同时尽可能地使填料、细小纤维与长纤维结合牢固等处理方法.     

Supercritical carbon dioxide extraction of the residual oil from palm kernel cake

Palm kernel cake contains residual oil that has never been retrieved and it is treated as wastes. In this study, supercritical carbon dioxide was used to separate the oil from the palm kernel matrix. The studied extraction parameters were at the set pressures 27.57, 34.47 and 41.36 MPa, temperatures 40-70 °C and carbon dioxide flow rate between 1 and 3 ml/min. The effect of the particle size on the oil yield was examined using different particle size that separated by sieving from ?106, ?150, ?180, ?250 and ?450 μm. The results showed that the highest oil removed was 9.26 g oil/100 g sample (p < 0.05) for the particle ?150 μm, and under extraction temperature of 70 °C, pressure 41.36 MPa, and carbon dioxide flow rate of 2 ml/min. The experimental results indicate that supercritical carbon dioxide extraction could be a viable technique to remove the remaining oil and to produce defatted palm kernel cake.     

Measurements and thermodynamic modeling of the solubility of squalene in supercritical carbon dioxide

The solubility of squalene in supercritical carbon dioxide (SC-CO₂) was measured and it was analyzed together with the values obtained by Catchpole and von Kamp (1997). The results showed that the experimental values obtained in this work agreed with the order of magnitude of those reported in the literature and correlated well with the Chrastil equation. The thermodynamic modeling using the Peng–Robinson equation of state only correlated well with the experimental values obtained when the critical properties and acentric factor reported by Ruivo et al. (2004) were used. The values predicted for the solubility of squalene in SC-CO₂ using modeling employing the GC-EOS, were only of the same order of magnitude as the experimental values for pressures below 200 bar, and its performance was influenced by the value of the critical hard sphere diameter.     

Effect of semi-drying on the antioxidant components of tomatoes

Three tomato cultivars (Excell, Tradiro, and Flavourine) grown under hydroponic conditions in a commercial greenhouse in New Zealand were semi-dried at 42 °C. The semi-dried tomatoes contained low levels of 5-hydroxymethyl-2-furfural and were significantly (p < 0.05) darker (lower CIELAB L* values) and had a higher mean a*/b* value (1.6) than the fresh tomatoes (1.2). The mean total phenolics in the semi-dried samples of tomatoes (300 mg gallic acid equivalents, GAE/100 g dry matter (DM)) was significantly lower than that of fresh tomatoes (404 mg GAE/100 g DM). The mean total flavonoid, and lycopene contents in the fresh samples (206 mg rutin equivalents/100 g DM, 63 mg/100 g DM, respectively) also showed a significant decrease after semi-drying (179 mg rutin equivalents/100 g, 54 mg/100 g DM, respectively). Ascorbic acid content in fresh tomatoes (284 mg/100 g DM) decreased to 223 mg/100 g DM after drying. The total antioxidant activity of the semi-dried tomatoes (1783 μmole trolox equivalents antioxidant capacity (TEAC)/100 g DM) was significantly (p < 0.05) lower than that of the fresh samples (2730 μmole TEAC/100 g DM).     

高压CO2处理对香蕉果肉中多酚氧化酶活性的影响

比较了CO2压力、温度和处理时间对香蕉果肉中多酚氧化酶活性的影响,并且采用二次回归正交旋转组合设计优化了高压CO2处理对香蕉果肉中多酚氧化酶的钝化条件.结果表明,影响高压CO2处理钝化香蕉果肉中多酚氧化酶活性的主次因素顺序为温度＞时间＞ CO2压力;高压CO2处理钝化香蕉果肉中多酚氧化酶的最佳条件为温度60℃、CO2压力19MPa、处理时间50min,在此条件下,香蕉果肉中多酚氧化酶的残活力仅为0.9％.     

微波干燥红枣浆生产红枣粉助干剂的研究

为了确定微波干燥红枣粉最佳助干剂配比,以陕北滩枣为原料,在前期实验确定微波干燥工艺条件的基础上,应用单因素和正交实验,以微波干燥红枣粉的集粉率和感官评价指标进行综合评定考察微波干燥的效果。结果表明:微波干燥工艺条件为主助干剂为麦芽糊精,红枣浆总固形物与主助干剂的配料比4:6,微波功率360W,间歇微波加热方式10s/60s,铺料厚度4mm时,优化的最佳助干剂配比分别为β-环糊精添加量15.0%、大豆分离蛋白添加量2.5%、可溶性淀粉添加量13.0%、卵磷脂添加量3.0%。应用该优化的技术工艺可达到最大限度地节省生产能耗,提高产品的集粉率和感官评价效果,产品外观色泽呈红色至微淡黄色。     

Effects of supercritical carbon dioxide treatment for sterilization purpose on meat quality of porcine longissimus dorsi muscle

The objective of this study was to investigate the effect of supercritical carbon dioxide (SC-CO₂) treatment for the sterilization purpose on meat quality and protein denaturation of the porcine longissimus dorsi muscle. The conditions of SC-CO₂ treatment were 7.4 and 15.2 MPa at 31.1 °C for 10 min. SC-CO₂ treatment had no effect on muscle pH, tenderness, and water-holding capacity (WHC). However, the samples treated at 7.4 MPa had a higher lightness value (52.97 vs. 46.94, P<0.001) and a more pronounced extent of sarcoplasmic protein denaturation (73.80 vs. 80.73, P<0.01) than the control samples. These results suggest that the paler color of samples treated with SC-CO₂ was associated with the sarcoplasmic protein denaturation, and the major denaturated proteins were determined to be phosphorylase b (PH), creatine kinase (CK), triosephophate isomerase (TPI), and one unknown protein. On the other hand, other quality traits were generally unaffected by the SC-CO₂ treatments at 7.4 or 15.2 MPa.     

新疆色买提白杏果肉汁饮料的生产工艺研究

小白杏果肉汁饮料,采用新疆色买提白杏鲜食加工兼用品种,通过合理工艺流程和加工设备,制定可行的工艺参数,解决了小白杏加工过程中的原色保留、滋味和纤维木质素的沉降问题,并在不添加任何防腐剂、化学添加剂和稳定剂的情况下,使该产品6个月内不发生褪色、分层。该项目已被新疆兵团科技局批准为“星火推广计划项目”。