超声协同钙浸渍对樱桃番茄贮藏过程中酚类物质的影响研究

研究超声协同钙浸渍处理对樱桃番茄贮藏过程中酚类物质的含量、结构和抗氧化能力以及相关酶活性的影响。结果表明:超声协同钙浸渍处理有效抑制贮藏期间樱桃番茄果实中多酚氧化酶(polyphenol oxidase,PPO)、过氧化物酶(peroxidase,POD)活性和苯丙氨酸转氨酶(phenylalanine ammonia-lyase,PAL)活性,维持总酚含量,延缓后熟。质谱结果表明,超声协同钙浸渍技术有效抑制贮藏期间樱桃番茄果实主要酚酸的消耗,更好的维持酚类物质的结构特性和抗氧化活性。综上所述,超声协同钙浸渍技术能够有效维持樱桃番茄贮藏期间品质特性,增加果实耐贮藏性。     

施硒对樱桃番茄贮藏品质及3种活性氧代谢酶的影响

为探寻施硒对樱桃番茄采后贮藏品质的影响并确定其适宜的处理浓度,在樱桃番茄发育过程中分次冲施不同浓度硒肥,分析番茄果实采收时及在贮藏过程中果实硬度、色泽、乙烯释放量、糖、酸、V_C含量及活性氧代谢相关酶活性的变化情况。结果表明,采收时2 mg/L硒处理的樱桃番茄果实硬度、可溶性糖含量、V_C含量与对照组相比分别增加了7.98%、5.29%和11.32%,并在贮藏过程中始终维持较高含量;同时2 mg/L硒处理提高了采后果实过氧化物酶活性(40.01~64.24 U/g)和超氧化物歧化酶活性(36.94~186.39 U/g);并在乙烯释放高峰时期(21 d)抑制乙烯释放量至8.01 μL/kg·h,延缓了樱桃番茄果实的采后衰老。而3 mg/L硒处理在贮藏42 d时对果实的活性氧代谢酶表现出负面影响,过氧化氢酶、过氧化物酶、超氧化物歧化酶活性分别低于对照组11.93%、23.09%和31.01%,不利于维持番茄果实的贮藏品质。2 mg/L为适宜的采前硒处理浓度,可以提升樱桃番茄果实品质及贮藏特性。     

贝莱斯芽孢杆菌发酵液对樱桃番茄贮藏品质的影响

樱桃番茄富含营养,在采后贮藏过程中其品质受到各种因素的影响而下降,为提高采后果实品质并延长货架期,亟待寻求一种安全有效的保鲜措施。以综合性评价、感官属性及风味与营养3个方面为评价指标,探究贝莱斯芽孢杆菌A4发酵液对樱桃番茄的保鲜效果。结果表明贝莱斯芽孢杆菌A4发酵液明显降低樱桃番茄的腐烂率和失重率,贮藏第12天,对照组腐烂率为27.97%,而发酵液处理组腐烂率为6.38%,且处理组的失重率显著低于对照组。贝莱斯芽孢杆菌A4发酵液可保持樱桃番茄的硬度、脆性、紧实度,延缓可滴定酸、可溶性固形物、类黄酮、番茄红素、酚类物质的损失,具有显著的保鲜效果。进一步探究发现贝莱斯芽孢杆菌A4发酵液可提高樱桃番茄超氧化物歧化酶（superoxide dismutase,SOD）、过氧化物酶（peroxidase,POD）、丙氨酸解氨酶（phenylalanine ammonia lyase,PAL）3种抗性酶的活性,并能够抑制丙二醛（malondialdehyde,MDA）的积累,从而保持樱桃番茄的贮藏品质。     

海藻酸钠和溶菌酶复合涂膜对樱桃番茄贮藏的保鲜效果

以海藻酸钠和溶菌酶为保鲜剂对樱桃番茄进行复合涂膜保鲜,研究不同浓度的海藻酸钠溶液对樱桃番茄贮藏保鲜效果的影响,分析了各处理组对樱桃番茄的感官品质、腐烂指数、失重率、硬度、呼吸强度、Vc含量、可溶性固形物含量以及SOD酶活性等生理生化指标的变化。结果表明:经1%海藻酸钠+0.1%溶菌酶处理后的樱桃番茄,在4℃条件下贮藏25 d后,其感官品质、果实的失重率明显优于其他处理,Vc含量为26.4mg/100g、可溶性固形物含量为10.9%、呼吸强度显著低于其他处理组,综合保鲜效果最佳。     

普鲁兰多糖涂膜处理对樱桃番茄保鲜效果研究

为探究不同质量浓度的普鲁兰多糖对番茄贮藏保鲜的影响，以樱桃番茄为试验材料，用0.005、0.01、0.02 g/mL普鲁兰多糖涂膜处理，评价普鲁兰多糖对樱桃番茄采后贮藏生理和保鲜效果的影响。研究结果表明，与对照组相比，普鲁兰多糖涂膜处理能够有效地降低果实的失重率，保持果实的硬度，使丙二醛含量和果胶酶活性维持在低水平状态，降低果肉细胞质膜的过氧化程度和果实软化程度，并且可以维持果实中番茄红素的含量，从而有效地保持樱桃番茄的营养价值并提高果实的货架期。     

不同颜色樱桃番茄品质研究

为进一步探究樱桃番茄颜色与品质之间关系,为培育优质樱桃番茄提供依据,测定5个颜色的15个品种樱桃番茄的营养品质、感官品质和外观品质,并对其颜色数据和感官评价得分进行分析。结果表明:不同颜色樱桃番茄品质差异较大, VB和VC红色品种樱桃番茄含量最高,粉色含量较低;绿色和黄色品种的樱桃番茄不含番茄红素和β-胡萝卜素,而红色相较紫色和粉色含有较多的番茄红素,但三者β-胡萝卜素含量差异不大;不同颜色樱桃番茄蛋白质含量接近,氨基酸总量粉色品种含量较高;外观品质的颜色指标(L和b)显著影响感官品质的果型和颜色得分,以及感官评价总分,表现为黄色是最受喜欢的樱桃番茄颜色,而绿色樱桃番茄感官评价总分最高。因此通过颜色可对番茄品质进行一定判定,为培育更受消费者喜爱的樱桃番茄品种提供理论依据和为消费者选购樱桃番茄提供建议。     

1-MCP和1-PentCP二次处理对樱桃番茄采后常温贮藏生理品质影响的比较

采用1μL/L 1-MCP(1-甲基环丙烯)或1-Pent CP(1-戊基环丙烯)2种环丙烯类乙烯抑制剂对变色期樱桃番茄果实(Lycopersicon esculentum var.cerasiforme)分别进行一次和二次处理,比较不同处理对果实在常温贮藏期间的生理和贮藏品质的影响。结果表明:与对照组相比,1-MCP与1-Pent CP二次处理均能有效保持樱桃番茄果实的硬度并延缓番茄红素和VC含量的降低、抑制果实呼吸强度和MDA(丙二醛)的积累以及细胞膜透性的增加、降低果实中POD(过氧化物酶)活性并推迟其活性高峰的出现,综合效果优于一次处理。     

番茄粉在加工和贮藏过程中番茄红素的稳定性研究

对番茄粉在加工和贮藏过程中番茄红素的稳定性进行了研究。番茄粉在加工和贮藏过程中,番茄红素将会发生氧化降解和异构化。采用高效液相色谱和二极管阵列分析测定了番茄红素的损失率以及番茄红素顺势异构体的变化。当番茄在85℃破碎1min时, 0.56%的番茄红素发生了降解。番茄浆料浓缩时,分别有6.24%和3.05%的番茄红素发生了氧化降解和异构化。在喷雾干燥过程中,约有1.1%的番茄红素发生了降解,2.1%的番茄红素变成了顺式异构体。当番茄粉在和37℃室温下贮藏6周后,番茄红素的保留率分别为70%和86%。     

采前3 种杀菌剂喷施对樱桃番茄采后品质的影响及啶菌噁唑残留检测

以金珠樱桃番茄为试材,研究采前杀菌剂喷施对采后樱桃番茄发病率、质量损失率和食用品质的影响,并测定樱桃番茄果实中啶菌噁唑残留变化。结果表明：采前喷施杀菌剂显著降低了金珠樱桃番茄采后发病率,提高了樱桃番茄果实中VC和可溶性固形物含量,减缓了VC和可溶性固形物含量贮藏期间的损失;但对质量损失率和可滴定酸含量的影响不显著（P＜0.05）。对樱桃番茄采后贮藏保鲜效果最好的杀菌剂为啶菌噁唑,喷施质量浓度为0.4 g/L。采前喷施啶菌噁唑后,樱桃番茄中啶菌噁唑残留在采前和采后均呈下降趋势;且采后樱桃番茄中啶菌噁唑残留下降的速度比采前下降的慢,贮藏温度越低,下降越慢。     

1-甲基环丙烯处理对樱桃番茄果实低温贮藏品质的影响

为了探讨低温贮藏条件下1-甲基环丙烯(1-methylcyclopropene,1-MCP)处理对樱桃番茄果实采后品质的影响,该研究以'粉娇'樱桃番茄为试材,测定了经1-MCP(0.14μL/L)处理的樱桃番茄在低温[(8±1)℃]贮藏期间果实腐烂率、呼吸强度、果实硬度、可溶性固形物、维生素C、有机酸和类胡萝卜素含量的...     

复合涂膜处理对圣女果的贮藏保鲜效果研究

以体积比为2:1的1.0%壳聚糖(CTS)与5.0%大豆分离蛋白(SPI)的复合涂膜液为基础,在其中分别加入0.2%硬脂酸(SA)、0.2%软脂酸(PA),对圣女果进行涂膜处理,以研究壳聚糖、蛋白质及脂类组成的复合膜对圣女果的保鲜效果。结果表明,复合涂膜处理能有效抑制圣女果贮藏期间聚半乳糖醛酸酶(PG)和果胶甲酯酶(PE)活性的上升,抑制圣女果硬度的降低和失重率的增加,保持较高的番茄红素含量和较低的呼吸强度,在一定程度上抑制膜脂过氧化产物丙二醛(MDA)的积累和V_C含量的降低,从而有效地保持了圣女果的贮藏品质,并且CTS/SPI/SA复合膜的效果要优于CTS/SPI/PA复合膜。     

Bio-preservation of fresh-cut tomatoes using natural antimicrobials

Effects of several natural volatile compounds such as methyl jasmonate (MJ), ethanol (ETOH), their combination (MJ–ETOH), tea tree oil (TTO) and garlic oil (GO) were evaluated on fresh-cut tomato storage at 5 °C for 15 days. Microbial growth, in-packaged atmosphere, quality attributes (firmness and color) and bioactive compounds (lycopene content, ascorbic acid and phenolic compounds) of fresh-cut tomatoes were determined. The shelf-life based on microbial growth was longer on fresh-cut tomatoes treated with natural volatile compounds than in control fresh-cut tomatoes. Treatment with ETOH combined with MJ was more effective in suppressing microbial proliferation than the individual treatments with each natural volatile compound. The lowest in-packaged atmosphere modification was detected in fresh-cut tomatoes treated by ETOH. In addition, this treatment better maintained firmness and color attributes than those treated with the other antimicrobial compounds. Related to the bioactive compounds, the use of MJ let keep higher content of lycopene, ascorbic acid and phenolic compounds than the other treatments. Thus, the shelf-life of fresh-cut tomatoes could be prolonged by the use of natural antimicrobials, which do not have significant negative effects on health-related compounds.     

组合保鲜技术对圣女果保鲜效果的影响

研究臭氧(ozone,O3)、乙烯去除剂(ethylene absorbent,EA)结合低温气调(controlled atmosphere,CA)组合保鲜处理对圣女果贮藏品质的影响。以广西百色市所产的圣女果为原料,分别进行以下处理:1-甲基环丙烯(1-methylcyclopropene,1-MCP)结合低温气调处理组(1-MCP+CA处理组),臭氧、乙烯去除剂结合低温气调组合保鲜处理组(O3+EA+CA处理组),以低温气调贮藏组作为空白对照(CK组),研究不同保鲜处理对圣女果贮藏期间失重率、腐烂率、呼吸强度、硬度、番茄红素、果糖、葡萄糖、苹果酸、柠檬酸、VC等指标的影响。结果表明:与CK组和1-MCP+CA处理组相比,O3+EA+CA处理组能够对圣女果起到保鲜效果,能够显著地降低圣女果的失重率、腐烂率、呼吸强度,可有效保持硬度、番茄红素、果糖、葡萄糖、苹果酸、柠檬酸、VC含量(P<0.05)。因此,臭氧、乙烯吸收剂结合低温气调处理对圣女果具有良好的保鲜效果。     

Effects of light-emitting diode illumination on the quality of fresh-cut cherry tomatoes during refrigerated storage

The effects of light-emitting diode (LED) illumination on the quality of fresh-cut cherry tomatoes were investigated. Tomatoes were exposed continuously to red, green, blue and white LED light for 7 days and control samples stored in darkness. Results showed that blue light treatment significantly led to more total soluble solids, lycopene concentration and individual phenolic compounds (chlorogenic acid, caffeic acid, rutin) after 7 days of storage. On day-5, green and blue light-treated tomatoes showed relatively higher firmness than samples treated by other lights and the control. At the early stage of storage, blue light could preserve the fresh flavour of tomatoes compared to other treatments. Overall, the blue light was most effective in the quality preservation of fresh-cut cherry tomatoes and could be used as a novel strategy in the preservation of fresh-cut fruits and vegetables during shelf life.     

不同减压处理对圣女果贮藏品质的影响

将圣女果分别放在101.3 kPa(常压)、80、50、20 kPa下,每4 d测定相关指标,研究减压处理对圣女果贮藏品质的影响。结果表明:减压处理可降低采后圣女果的失重率、呼吸强度,抑制Vc含量、可滴定酸含量、可溶性固形物含量、原果胶含量的降低,减缓细胞质膜透性、花青苷含量的上升,从而保持了其贮藏期的品质,延缓其衰老速率,其中以50 kPa处理效果佳。     

基于高压静电场处理的樱桃番茄果实贮藏期生理品质及其代谢

樱桃番茄色泽艳丽,味道酸甜适口,受到消费者欢迎。但樱桃番茄采后容易腐烂变质,且鲜食时其表面致病菌不利于消费者健康。本实验以‘黄妃’樱桃番茄为材料,通过大肠杆菌菌落总数、腐烂率、生理指标测定以及代谢组学分析,研究高压静电场（high voltage electrostatic field,HVEF）处理对樱桃番茄果实贮藏期生理品质及代谢的影响。结果表明,HVEF处理能显著降低果实表面的大肠杆菌菌落总数（P＜0.05）,并能延缓贮藏期间果实腐烂,且对呼吸速率和质量损失率没有明显影响,果实乙烯释放量在贮藏早期受到抑制。代谢组学分析结果表明,HVEF处理能引起部分代谢物质的含量差异,且存在多种上调和下调模式,其中部分类黄酮和生物碱类物质含量上升。综上,HVEF处理能够降低果实采后腐烂率和表面致病菌数量,并对改善樱桃番茄果实采后品质有一定的作用。     

玉米醇溶蛋白膜的制备及其保鲜效果评价

该实验制备了负载大蒜素-丁香酚的玉米醇溶蛋白膜,并评价其对圣女果的保鲜效果。研究表明大蒜素-丁香酚混合精油的加入量为1.50%时（体积分数）,所制得的玉米醇溶蛋白膜在外观、厚度、透明度等方面表现良好。用此配方对圣女果进行覆膜处理,负载大蒜素和丁香酚的蛋白膜与空白膜和对照相比,在贮藏期间圣女果的失重率、腐烂软化率、褐变度均小于空白对照组,在第8天各项指标分别较对照降低22.92%、50.00%、19.11%;圣女果的维生素C含量在第8天较对照提高1.69%,在第10天可溶性糖含量较对照提高9.58%。实验结果表明,负载大蒜素-丁香酚的玉米醇溶蛋白膜在减少圣女果水分流失、抑制腐烂和抗氧化等方面的性能均有了明显的提高,可以进一步开发成蔬果保鲜剂进行应用。     

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.     

不同钙制剂处理对番茄冷藏期间品质的影响

以“辽园多丽”番茄研究花期喷施不同种类的钙剂,对改善番茄品质及冷藏品质的影响。经实验可知各处理硬度、可溶性固形物含量、还原糖含量、可滴定酸含量和游离氨基酸含量冷藏期间均呈下降趋势,泛酸钙处理硬度下降最为最慢,冷藏结束硬度为14.33kg/cm2,其他各指标下降最缓慢的均为腐植酸钙处理。转红指数呈上升趋势,冷藏结束时腐植酸钙处理最高,比对照高19%。番茄红素含量腐植酸钙处理最高为4.55mg/100g。腐植酸钙处理总体优势明显,与对照差异极显著。