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1.
杨震峰  王臻哲  金鑫 《食品科学》2010,31(20):481-484
研究不同贮藏温度(0℃和25℃)对红肉枇杷“大红袍”和白肉枇杷“宁海白”果实贮藏期间果实可溶性固形物、可滴定酸、出汁率、相对电导率、总酚和木质素含量的影响。结果发现,枇杷果实采后贮藏期间可溶性固形物和可滴定酸含量减少,果肉出汁率快速下降,果实贮藏品质发生劣变。低温(0℃)贮藏可维持较高含量的 可溶性固形物和可滴定酸含量,却促进贮藏后期总酚含量的减少和木质素的积累,导致果实木质素败坏的发生,降低了果实的食用品质。在25℃贮藏期间,枇杷果实木质素含量也呈增加趋势。表明枇杷果实采后木质化败坏是一种衰老现象,不适当的低温贮藏会加剧这种衰老现象的发生。  相似文献   

2.
热处理对龙眼果实采后生理和贮藏品质的影响   总被引:4,自引:0,他引:4  
探讨了热处理对龙眼果实采后生理和品质的影响。用50℃热水处理龙眼果实10 min,晾干,用聚乙烯薄膜袋密封包装,置于(15±1)℃下贮藏。贮藏期间定期测定果实呼吸强度、失重率、果皮细胞膜相对渗透率、果皮丙二醛(MDA)、叶绿素、类胡萝卜素、花色素苷、类黄酮和总酚含量、果肉可溶性固形物(TSS)、可滴定酸(TA)、可溶性糖、还原糖和维生素C含量、果皮褐变指数和果肉自溶指数等指标。结果表明:与对照果实相比,50℃热水处理10 min,可有效降低采后龙眼果实呼吸强度,减少果实失重率,延缓果皮MDA含量和细胞膜相对渗透率的升高,保持较高的果皮叶绿素、类胡萝卜素、花色素苷、类黄酮和总酚含量和果肉TSS、TA、可溶性糖、还原糖和维生素C等营养成分含量,降低果皮褐变指数和果肉自溶指数。该处理可有效延缓采后龙眼果实衰老,提高龙眼果实贮藏品质。  相似文献   

3.
研究不同剂量UV-C照射处理对采后芦柑在15℃贮藏期间腐烂率及主要品质指标的影响。结果表明,1.5kJ/m2或3kJ/m2UV-C照射能有效减轻果实贮藏期间腐烂,推迟腐烂6d或12d,显著降低腐烂率。贮藏后期,1.5kJ/m2或3kJ/m2处理降低了失重率,提高了果实的可溶性固形物含量、糖酸比和VC含量,且促进了果肉中类黄酮和总酚的次生代谢合成,从而较好地保持了果实的感官品质和营养品质。1.5kJ/m2或3kJ/m2处理也有助于提高果皮中类黄酮和总酚含量。UV-C照射处理作为采后芦柑的非化学贮藏保鲜手段,具有潜在的应用前景。  相似文献   

4.
本实验以杏梅果实为供试材料,采用不同贮藏温度(0、2、4、6℃),以杏梅果实腐烂率、失重率、可溶性固形物含量、可滴定酸含量等为参考指标,研究贮藏温度对杏梅果实采后贮藏期间品质的影响。结果表明:不同贮藏温度对杏梅贮藏品质的影响效果不同。与4℃和6℃贮藏相比,0℃和2℃可以显著降低杏梅果实贮藏期间腐烂率和失重率,同时较好地维持杏梅果实贮藏期间的硬度、可溶性固形物含量(TSS)、可滴定酸含量(TA),也有效抑制了杏梅果肉总酚含量和VC含量的下降,使其抗氧化活性保持在较高水平。  相似文献   

5.
采后失水是百香果果实在贮运流通和销售环节最显著的品质劣变特征之一,严重影响其商品价值。本文利用低场核磁共振技术(Low Field Nuclear Magnetic Resonance,LF-NMR)研究采后黄金百香果果实在贮藏过程中的失水过程,并解析失水规律与品质劣变的关系。LF-NMR结果显示,黄金百香果在贮藏过程中,果浆和果皮的质子密度大幅下降,与外观严重失水表现一致;此外,果实失水以自由水为主,其含量下降了14.98%,结合水在贮藏后期显著减少,失水程度与果实采后成熟和衰老进程有关。进一步研究表明,黄金百香果采后成熟期有两个呼吸高峰,此时失水及其引起的失重较小,果皮叶绿素减少和类胡萝卜素增加促进了亮度和色调升高,果浆可溶性固形物保持在较高含量,可滴定酸含量和果实硬度均下降,果实正常完成后熟,极少出现腐烂;而在果实衰老期,呼吸速率下降,失水和失重加剧,果皮类胡萝卜素的迅速减少降低了表面亮度和色泽,果浆可溶性固形物和可滴定酸含量以及果实硬度下降,腐烂率迅速升高。因此认为,黄金百香果完熟后严重失水,不仅造成果实失重、失鲜,还可加剧其生理代谢以及细胞和组织结构变化,降低果实耐贮性,加快品质劣变。本研究可为百香果采后失水劣变机制和相应保鲜控制技术研究提供参考,并为果蔬采后水分状态的无损检测提供借鉴。  相似文献   

6.
过氧化氢对采后龙眼果实贮藏品质的影响   总被引:1,自引:0,他引:1  
过量的活性氧是导致果蔬采后品质劣变的主要原因之一。以活性最为稳定的过氧化氢作为活性氧,研究活性氧对采后龙眼果实贮藏品质的影响。结果显示:与对照龙眼果实相比,过氧化氢处理的龙眼果实采后贮藏期间具较低的果皮叶绿素、类胡萝卜素和类黄酮等色素含量,较低的果肉可溶性糖、蔗糖和VC等营养物质含量,较高的龙眼果皮褐变指数和果肉自溶指数,及较低的龙眼果实商品率。据此认为,活性氧在采后龙眼果实品质劣变中起重要的促进作用,活性氧会促进采后龙眼果实外观品质劣变和果肉营养物质的降解,从而降低采后龙眼果实商品价值。  相似文献   

7.
为了探讨MeJA处理对枇杷果实抗氧化能力的影响,研究了10μmol/L MeJA处理的"大红袍"枇杷果实在1℃贮藏过程中维生素C、总酚、总黄酮、总类胡萝卜素含量及抗氧化活性的变化。结果表明,枇杷果实在贮藏过程中维生素C和总黄酮含量下降,而总酚和总类胡萝卜素含量呈先上升后下降的趋势。10μmol/L MeJA处理可显著抑制果实中维生素C和总黄酮含量的下降,促进贮藏前期总酚和总类胡萝卜素含量的上升。在1℃贮藏过程中,枇杷果实DPPH和超氧阴离子自由基清除能力随着贮藏时间的延长呈先上升后下降趋势,并且抗氧化活性的变化与总酚和总类胡萝卜素含量的变化呈显著正相关,而与维生素C和总黄酮含量的变化相关性较低。这表明MeJA是通过影响枇杷果实中酚类和类胡萝卜素物质的代谢来维持枇杷果实采后较高的抗氧化能力和营养价值。  相似文献   

8.
研究了龙眼"立冬本"果实在采后(25±0.5)℃和(3±0.5)℃温度下的呼吸强度、细胞膜透性和品质的变化。结果表明:龙眼果实属于非呼吸跃变型果实;在(25±0.5)℃下贮藏4天,果实呼吸强度下降,之后明显上升;果实采后果皮细胞膜透性快速增加,果实易失重、衰老、腐烂和果皮褐变,贮藏后期果肉自溶;果肉可滴定酸和维生素C含量快速下降,总糖和蔗糖含量下降,还原糖含量先升后降,可溶性固形物含量在贮藏前期下降而后期上升,可溶性固形物和可滴定酸比值先升后降;贮藏后期果肉可滴定酸含量增加。而(3±0.5)℃低温贮藏可显著降低果实呼吸强度,抑制病原菌生长,延缓果实衰老和果皮细胞膜透性增加,延迟果皮褐变,减少果实失重和果肉营养成分变化,抑制果肉自溶,保持果实较高的品质,延长果实贮藏期。  相似文献   

9.
研究了建阳桔柚果实采后贮藏期间生理和营养成分的变化规律。试验结果表明,随着贮藏时间的延长,桔柚果实的呼吸强度、失重率、汁胞枯水指数、果皮细胞膜渗透性、乙醇含量呈上升趋势,建阳桔柚果肉可溶性固形物含量、总糖含量、类胡萝卜素含量呈现先上升后逐渐下降的趋势,而可滴定酸含量、Vc含量是呈逐渐下降趋势。  相似文献   

10.
以福建云霄解放钟枇杷为试材,采用10,20,50 μmol/L 外源茉莉酸甲酯(MeJA)熏蒸8 h,通过检测(4±1) ℃贮藏过程中可溶性固形物(TSS)、总糖、维生素C、总酸(TA)含量和呼吸强度、失重率、乙烯释放速率、腐烂率等指标,研究MeJA熏蒸处理对枇杷果实采后品质的影响。结果表明,20 μmol/L MeJA熏蒸处理可抑制枇杷果实呼吸强度、降低失重率和贮藏前期乙烯释放速率,维持总糖、维生素C、TA和贮藏后期较高TSS含量。基于外源MeJA的浓度效应,10 μmol/L MeJA处理对枇杷果实失重率影响不显著,50 μmol/L MeJA处理对保持枇杷果实维生素C、总糖、TA和贮藏后期的TSS含量效果不明显。综上,20 μmol/L MeJA处理对枇杷果实采后品质有积极影响。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.  相似文献   

13.
Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.  相似文献   

14.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of  相似文献   

15.
《印刷工业》2014,(9):94-95
In the 2014 China(Shanghai)International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;  相似文献   

16.
正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly  相似文献   

17.
《造纸信息》2014,(8):99-100
On December 24th, 2013, the meeting on the selection of top 10 news of China's paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.  相似文献   

18.
《造纸信息》2014,(8):83-84
In Apri Commi major p Plan" (h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the "13th Five-Year ereafter referred to as "The Announcement")  相似文献   

19.
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the latest scientific  相似文献   

20.
正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,  相似文献   

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