姜油树脂对采后橄榄果实抑菌效果和贮藏品质的影响

小孢拟盘多毛孢（Pestalotiopsis microspora）是引起橄榄果实腐烂的最主要病原菌之一。为给姜油树脂在采后橄榄果实贮藏保鲜应用提供科学依据和实践指导,本实验研究了姜油树脂对采后橄榄果实的抑菌效果和贮藏品质的影响。以‘长营’橄榄果实为材料,通过损伤接种法,研究不同剂量的姜油树脂对P. microspora接种橄榄果实的抑菌效果,并进一步探讨最佳抑菌剂量的姜油树脂对采后橄榄果实在25 ℃下贮藏49 d期间果实病害发生和品质的影响。结果表明：与对照比较,姜油树脂可显著抑制P. microspora侵染所致橄榄果实采后病害发生,其中姜油树脂的最佳抑菌剂量为30 μL/mL;30 μL/mL的姜油树脂处理可显著降低橄榄果实病害指数和果皮褐变指数（P＜0.01）,延缓橄榄果实可溶性固形物、可溶性总糖、可滴定酸、VC、总酚及类黄酮含量的下降,较好保持采后橄榄果实的外观颜色和营养品质。因此认为,30 μL/mL的姜油树脂处理可有效控制橄榄果实采后病害发生,保持橄榄果实贮藏品质。     

微波对台湾青枣果实采后营养品质的影响

采用家用微波炉对采后台湾青枣果实进行微波处理,研究处理后果实的贮藏寿命及营养品质变化。结果表明:20～25 s的微波处理,能延缓果实呼吸高峰的出现,对果实贮藏期间可溶性固形物、有机酸及Vc的降解有一定的抑制作用,减缓了果实含水量的下降,提高了果实的好果率,使贮藏寿命延长了2～3 d。     

低功率微波处理佐贺清香草莓的生物效应

试验探索了低功率微波处理对草莓采后成熟与衰老的影响。采用不同微波输出功率,120 s处理"佐贺清香"草莓,处理后于1℃贮藏,定期检测果实的生理生化及品质指标。结果表明:低功率微波处理对果实温度上升无明显影响,对呼吸速率有显著抑制,可延缓果实在贮藏期间可溶性固形物、还原糖、可滴定酸、VC含量的下降,保持较高的果实硬度,纤维素酶活性和MDA含量较对照低。其中100 W/120 s微波处理效果最优。当微波功率大于165 W/120 s时,对草莓生理和品质有损伤,说明低功率微波处理对草莓保鲜有一定生物效应影响,可起到延缓草莓的成熟与衰老的作用。     

机械损伤对橄榄采后品质及其生理的影响

通过人工上树采摘、拦网采摘和自然掉果三种采收方式,探讨不同程度的机械损伤对橄榄采后商业品质及其生理的影响,结果表明:橄榄果实受到机械损伤后,在贮藏期间,果实的失重率和可溶性固形物呈线性增加,细胞膜透性增大,有机酸和VC的含量减少,含水量快速下降,呼吸速率迅速提高,PPO、POD、CAT活性上升,加速了果实的衰老进程.轻采轻放,减少机械损伤,对延长橄榄果实贮藏寿命,提高果品商业品质具有积极意义.     

橄榄果实采后病害和保鲜技术研究进展

橄榄果实易发生采后病害而导致果实失水皱缩和不耐贮藏,严重影响橄榄产业的发展。为延长橄榄果实贮藏期提供理论依据和实践指导,对国内外橄榄煤烟病、炭疽病、焦腐病、果腐病、灰斑病、疫病、青霉病等橄榄果实主要采后侵染性病害的症状及其病原特征,采后生理性病害如低温冷害,及橄榄果实采后贮藏保鲜技术的研究进展进行了综述。     

低温贮藏对"长营"橄榄果实采后生理和品质的影响

研究了"长营"橄榄果实在(15±1)℃和(8±1)℃下贮藏的果实呼吸强度、细胞膜透性和品质的变化.结果表明:在(15±1)℃下贮藏的橄榄果实呼吸强度高,呼吸高峰较旱出现,果实细胞膜透性、失重率和果皮褐变指数增加,果实好果率低.而(8±1)℃低温贮藏可降低橄榄果实呼吸强度,延缓呼吸高峰出现,抑制果实细胞膜透性和果皮褐变指...     

不同功率的微波处理对猕猴桃贮藏特性的影响

在微波处理量、处理时间、输出功率等对皖翠猕猴桃果心温度影响检测的基础上,研究了微波处理后PE保鲜袋折口包装,(1±0.5)℃贮藏对果实贮藏品质的影响。结果表明不同输出功率的微波处理猕猴桃(1500±50)g/次,处理时间60s,果心温度存在一定的差异;贮藏实验表明低功率处理组果实品温上升不明显,能有效地推迟猕猴桃呼吸峰的出现,抑制呼吸速率、可溶性固形物(SSC)含量的上升;抑制猕猴桃硬度、可滴定酸含量、V C含量的下降,保持其营养品质;能显著抑制LOX酶活性、电导率的上升,延缓皖翠猕猴桃的成熟衰老。当处理功率高于300W时,对猕猴桃的生理有一定的损伤,不利于贮藏。120W/60s微波处理组合为最优组合。     

微波处理用于采后番茄保鲜效果研究初探

为了解决番茄采后不耐贮藏的问题,研究了不同功率微波条件对番茄进行处理后品质的变化,从中找出对番茄品质保持最好的微波处理条件。将采后的番茄经过100%(A组)、50%(B组)、30%(C组)功率的微波分别处理10、20、30、40s,常温下避光贮藏,定期检测各处理与对照果实的腐烂率、杀菌率、VC含量、失重率、可滴定酸含量、可溶性固形物含量的指标,通过对实验结果的观察分析可以看出,微波处理具有一定的杀菌作用,但在品质指标方面各处理组都低于对照组。其中100%功率微波处理10s的番茄各项指标下降幅度最小,并且腐烂率最低,为10%。     

微波处理对货架期石榴品质的影响

利用微波炉对采后石榴果实进行辐照处理,研究处理后果实在货架期的生理变化及贮藏品质。结果表明：10～20s 短时微波处理可抑制果皮多酚氧化酶(PPO)活性,减轻果实的褐变程度,保持果皮较高的多酚含量,减缓可滴定酸(TA)含量降低的速度,较好的保持了可溶性固形物含量(SSC)。10～20s 是适宜的微波处理时间,超过20s会产生热伤害,加重果实褐变。     

橄榄果实冷藏期间失重影响因素的研究

对福建省10个主栽橄榄品种果实在8℃、RH85%贮藏条件下的果实失重率及贮藏温度(2℃、6℃、10℃、20±1℃室温)、贮藏时间及包装对果实失重率的影响进行研究.结果表明,橄榄各品种随贮藏天数的增加,果实失重率呈线性增加;供试的10个橄榄品种,以中长营最易失水,福州品种群大长营、中长营、小长营较容易失水,莆仙品种群厝后本、刘族本保水性能较好,其中刘族本果实失重率显著(P<0.05)地低于其它品种果实.没有包装的檀香橄榄果实失重率与贮藏温度、贮藏时间呈显著(P<0.05)正相关,即橄榄果实失重率随贮藏温度升高(相关系数r=0.9560～0.9999),贮藏时间延长(r=0.9692～0.9960)而增加,且它们间存在互作效应,橄榄不同品种与贮藏时间之间也存在互作效应.用0.04mm厚聚乙烯薄膜袋包装,可有效地控制橄榄果实的自然失水,与对照组没有包装间存在极显著(P<0.01)差异,因而延长了橄榄果实贮藏期.     

初榨橄榄油中的微生物群及其对橄榄油品质的影响

初榨橄榄油生产环境相对开放,榨取橄榄油的原料、环境及设备中的微生物群都可能进入初榨橄榄油,对油脂品质产生影响。为全面认识初榨橄榄油中微生物群以及从微生物层面控制初榨橄榄油品质,从食品微生物学研究的视角,综述了初榨橄榄油中酵母菌、细菌和霉菌等主要微生物群,分析了油橄榄枝叶、果实和初榨橄榄油中的微生物群对油脂品质的影响,介绍了采后储存的油橄榄果实及储存期的初榨橄榄油品质与微生物群之间的关系,探讨了对有害微生物群影响初榨橄榄油品质的防控措施。研究认为酵母菌对初榨橄榄油储存期间的品质起主要的影响作用。通过避免采摘和储存过程中油橄榄果实的损伤,保证加工过程中清洗用水和设备的洁净,控制储存环境温度、光照和氧含量等措施,可以有效防控有害微生物对橄榄油品质的负面影响。     

橄榄矿质元素的测定及品质比较

采用微波消解- 火焰原子吸收光谱法,测定粤东地区不同橄榄品种果实中10 种矿质元素的含量。结果表明,各种橄榄的矿质元素含量高低顺序基本一致,但是含量大小有差异;差异的原因除了环境因素外,还与遗传因素、元素吸收率有关。21 种橄榄中10 种矿质元素含量分别是：Ca 2040.20～4348.89mg/kg、Mg 926.38～1175.12mg/kg、Na 78.77～143.55mg/kg、Fe 80.17～88.27mg/kg、Mn 39.47～62.30mg/kg、Zn 23.13～28.71mg/kg、Cu 9.59～16.39mg/kg、Cr 3.17～12.95mg/kg、Co 2.30～4.04mg/kg、Ni 1.23～1.27mg/kg。土榄、青皮、下院和小丁香属于优良品种,它们含有丰富的矿质元素。     

初榨橄榄油中多酚类化合物含量随油橄榄果 生长发育的累积变化

旨在为甘肃陇南橄榄油的质量评价和油橄榄鲜果采收时间提供指导,探究了不同品种初榨橄榄油（VOO）中多酚类化合物（PPs）随油橄榄果生长发育的累积变化。以甘肃陇南不同成熟度的8个品种油橄榄鲜果为原料,采用压榨法获得VOO,利用反相高效液相色谱法同时测定VOO中的9种PPs含量。结果表明：VOO中总多酚的含量主要由酪醇和橄榄苦苷决定,橄榄苦苷是含量最高的PPs,且其含量随油橄榄果成熟度指数（MI）变化最明显;VOO中木犀草苷含量均较低,阿魏酸和芹菜素仅在个别品种中检测到,芦丁在所测油品中均未检测到;‘阿斯’‘鄂植8号’‘中山24号’和‘佛奥’4个品种VOO的PPs评估数据表现良好,分别在MI为0～1.0、2.0～4.0、0～2.0和5.0～7.0表现最佳,建议这4个品种油橄榄鲜果的采收时间分别为9月下旬、11月上旬、9月下旬至10月上旬以及11月下旬,而‘切姆拉尔’VOO在PPs种类和总含量等评估数据中表现不佳。综上,可以依据不同MI的油橄榄鲜果制备的VOO中多酚含量,尤其是酪醇和橄榄苦苷含量,确定不同品种油橄榄鲜果的采收时间,并进行VOO的品质评价。     

品种和成熟度对油橄榄鲜果功效成分及抗氧化能力的影响

油橄榄鲜果被广泛用作加工药材或作为蔬菜食用,不同品种及成熟度对其药用和食用价值具有重要影响。 本实验研究了10 个具有代表性的油橄榄品种（白橄榄、豆果、鄂植、佛奥、卡林、科拉蒂、克罗莱卡、皮瓜尔、 云台和配多灵）及3 个成熟度（早、中、晚）对其功效成分（总酚、总类黄酮、总黄烷-3-醇、橄榄苦苷和羟基酪 醇）和抗氧化能力（铁离子还原能力、清除1,1-二苯基-2-苦基苯肼自由基、羟自由基和超氧阴离子自由基能力）的 影响,并通过相关性和主成分分析研究了油橄榄鲜果不同品种及成熟度与所分析指标之间的关联性。研究发现：不 同油橄榄品种及成熟度对其功效成分影响程度不同,并且品种对所分析指标的影响大于成熟度;随着成熟度的增 加,油橄榄鲜果提取物的抗氧化能力（除清除超氧阴离子自由基能力）呈现增强趋势。通过对不同品种及成熟度的 油橄榄鲜果功效成分和抗氧化能力进行分析,为油橄榄品种的选育、采收、加工和应用提供理论依据。     

微波技术应用(英文)

As a new development technique microwave technology has applied widely in areas of food processing.This article summarized the principles and characteristics of microwave technology and applications of microwave processing technology in meat products, cereals, fruits and vegetables processing.Some problems existed in microwave applications were analyzed.The development trend of microwave processing technology in food industry was put forward.     

Ultrasound-accelerated debittering of olive fruits

Effects of ultrasound-accelerated debittering (UAD) at different NaOH concentrations (1.50, 1.75, and 2.00% w/v) and temperatures (25, 30 and 35 °C) on physicochemical and textural properties of olive fruits were investigated and compared with conventional debittering (CD). In UAD, processing time decreased up to 48% in comparison with CD method. During debittering, increasing moisture and decreasing nitrogen and ash contents of the samples were observed. In UAD, reduction rate of phenolic compounds and as a result the speed of debittering process increased in comparison with CD method. UAD was able to reduce textural hardness at a higher rate than CD method. Fatty acid compositions of UAD and CD samples were similar. Both UAD and CD methods similarly caused considerable damages to the structure of olives as observed on micrographs. Overall, UAD method was able to debitter olive fruits at a higher rate without causing any undesirable changes. This can have practical implications in reducing NaOH and water usage for olive processing.Industrial relevanceIn this research, the efficacy of ultrasound-assisted debittering (UAD) of olive fruit was evaluated. UAD increased the rate of sodium hydroxide penetration into the olive flesh, leading to a higher rate of oleuropein hydrolysis and significant reduction of processing time of up to 48% in comparison with CD method. Therefore, ultrasound-assisted debittering was found to be a suitable and applicable technique in minimizing debittering time of olive fruits and reducing NaOH concentration. It is also possible to reduce the number of wash-cycles required for the completion of debittering resulting in substantial reduction in water usage.     

Estimation of olive oil acidity using FT-IR and partial least squares regression

Olive oil characteristics are directly related to olive quality. Information about olive quality is of paramount importance to olive and olive oil producers, in order to establish its price. Real-time characterization of the olives avoids mixtures of high quality with low quality fruits, and allows improvement of olive oil quality. This work describes an indirect determination of olive acidity and that allows a rapid evaluation of olive oil quality. The applied method combines chemical analysis (30 min Soxhlet olive pomace extraction) in tandem with a spectroscopic technique (FT-IR) and multivariate regression (PLS1). The most suitable calibration model found used SNV pre-processing and was built with 4 Latent Variables giving a RMSECV of 8.7% and a Q² of 0.97. This accurate calibration model allows the estimation of olive acidity using a FT-IR spectrum of the corresponding Soxhlet oil dry extract and therefore is a suitable method for indirect determination of FFA in olives.     

肉类保藏技术(五) 微波技术的应用

微波技术作为一种新兴技术,已广泛地应用于食品加工等领域。本文介绍了微波加热的原理、特点,介绍了近年来微波技术在肉制品、谷类和果蔬等食品原料中的应用技术研究,分析了微波技术的现状及存在的问题,提出了微波技术在食品工业中的应用研究前景。     

Pre-processed fruits as raw materials: part II—process conditions,demand and safety aspects

The demand for pre-processed fruits has grown rapidly in recent years as a result of consumer attention towards fresh, healthy and convenient foods. Most of the fruits are available seasonally and they are perishable, so it is necessary to have a continuous supply of the fruits to avoid the blockages in the fruit processing industry. The review is written in the purview of this issue, and it presents pre-processed fruits as a sustainable solution. The present review is part II of the series of articles on pre-processed fruits as the raw material for various food industries. The fruits covered here are mango, pineapple, pear, olive and papaya. The article continues to emphasise the critical processing and storage condition for these fruits ranked higher in terms of their production quantity and economic value. The fruits are critically reviewed for their processing, storage and safety aspects along with key research findings of different processing techniques. The important safety aspects associated with such processed commodities are also discussed.     

Volatile phenols in virgin olive oils: Influence of olive variety on their formation during fruits storage

The potential significance as odorants and markers of olive fruits degradation has been recently pointed out for volatile phenols in virgin olive oil (VOO) and related to the appearance of VOO sensory defects. The few studies carried out in order to elucidate the factors affecting their formation in olive fruits or VOOs, indicated that they could be considered as analytical indices of olive fruits degradation during storage, likely reflecting the microbiological activity. In the present study, the effect of the olive variety (‘Arbequina’, ‘Arbosana’ and ‘Leccino’) on the production of volatile phenols during twelve days of storage in closed plastic bags was evaluated. The different resistance of each variety to the microbiological attach was observed during olive fruit storage, and it was reflected by the evolution of guaiacol, 4-ethylphenol and 4-ethylguaiacol, and related to free acidity values. On the contrary, a scarce dependence on the microbial growth or varietal factors was observed for 4-vinyl derivatives, which appeared more directly related to the time of olives storage. The evolution of volatile phenols found certain correspondence in the sensory characteristics of the resulting VOOs, while the rest of VOO chemical quality indices did not show major variations during fruits storage.