外源柠檬酸处理对杨桃采后后熟及衰老的影响

为探索杨桃采后果实保鲜新方法,研究外源柠檬酸对采后杨桃后熟衰老及保鲜效果的影响。以广东湛江红杨桃为试材,采用5、10 mmol/L的柠檬酸溶液浸泡果实20 min并在15℃下贮藏,研究柠檬酸处理对果实的后熟软化及相关生理指标的影响。结果表明:柠檬酸处理有效延缓了杨桃果实硬度的下降、可溶性固形物含量的上升、可滴定酸含量的降低、细胞膜透性的上升以及果实VC含量的下降;柠檬酸处理还能提高果实贮藏后期POD的活性;同时,柠檬酸处理也抑制了果实中PPO活性的升高和MDA含量的积累。相关性分析表明,柠檬酸处理果实的硬度与POD活性、PPO活性及可滴定酸含量密切相关。外源柠檬酸能有效地抑制采后杨桃的后熟衰老进程,有较好的保鲜效果。     

1-MCP处理对杨桃果实采后生理和贮藏品质的影响

该文探讨1-甲基环丙烯（1-MCP）处理对“香蜜”甜杨桃果实采后生理和贮藏品质的影响。采后‘香蜜’甜杨桃果实用0.6 μL/L的1-MCP处理12 h后,在(15±1） ℃、相对湿度90%下贮藏。贮藏期间测定果实呼吸强度、细胞膜相对渗透率、果皮叶绿素和类胡萝卜素含量、果实硬度、可溶性固形物和可滴定酸含量、果实好果率、失重率及感官品质等指标的变化。结果表明：与对照果实相比,1-MCP处理能有效降低杨桃果实的呼吸强度和呼吸峰值,抑制果实外观颜色转变,保持较高的果实硬度和可滴定酸含量,延缓果实细胞膜相对渗透率升高,减少果实失重和腐烂。经1-MCP处理的果实在(15±1) ℃、相对湿度90%下贮藏20 d时的好果率为78%,而对照果实只有63%。因此认为,0.6 μL/L 1-MCP处理可延缓采后‘香蜜’甜杨桃果实成熟衰老和保持果实贮藏品质。     

1-MCP处理对杨桃果实采后生理和贮藏品质的影响

该文探讨1-甲基环丙烯(1-MCP)处理对"香蜜"甜杨桃果实采后生理和贮藏品质的影响。采后"香蜜"甜杨桃果实用0.6μL/L的1-MCP处理12 h后,在(15±1)℃、相对湿度90%下贮藏。贮藏期间测定果实呼吸强度、细胞膜相对渗透率、果皮叶绿素和类胡萝卜素含量、果实硬度、可溶性固形物和可滴定酸含量、果实好果率、失重率及感官品质等指标的变化。结果表明:与对照果实相比,1-MCP处理能有效降低杨桃果实的呼吸强度和呼吸峰值,抑制果实外观颜色转变,保持较高的果实硬度和可滴定酸含量,延缓果实细胞膜相对渗透率升高,减少果实失重和腐烂。经1-MCP处理的果实在(15±1)℃、相对湿度90%下贮藏20 d时的好果率为78%,而对照果实只有63%。因此认为,0.6μL/L 1-MCP处理可延缓采后‘香蜜’甜杨桃果实成熟衰老和保持果实贮藏品质。     

柠檬酸处理对鸭梨果实贮藏特性的影响

测定2%柠檬酸(CA)处理对套袋鸭梨贮藏品质等贮藏性的影响。结果表明,CA处理有效地延缓了贮藏中果实硬度、可溶性固形物、可滴定酸和Vc含量的下降,有效地控制了果实表皮褐变、果柄失水干枯变黑和腐烂的发生。     

热处理对红贵妃芒果贮藏品质及保鲜效果的影响

研究采后50℃热水处理10、15和20min对红贵妃芒果果实贮藏品质及某些生理性状的影响。结果表明:与对照相比,热水处理能显著抑制贮藏期间红贵妃芒果果实硬度、可滴定酸(TA)含量和VC含量的下降,延缓病情指数、总可溶性固形物(TSS)含量的上升,维持较高的SOD活性,抑制MDA的积累,从而改善了红贵妃芒果的贮藏品质,延缓了果实的成熟与衰老。综合结果认为10min和15min热水处理的效果较好。     

1-MCP处理对蓝莓冷藏保鲜效果的影响

以'蓝丰'蓝莓(Vaccinium corymbosum L.'Bluecrop')果实为试材,采用1.0μL/L1-甲基环丙烯(1-MCP)处理蓝莓24 h,研究1-MCP处理对蓝莓果实冷藏保鲜效果的影响。对蓝莓果实贮藏进程中的硬度、弹力、黏力等质构特性,以及相关生理指标失重率、VC含量、花青苷含量和抗氧化能力等进行测定。结果表明:1-MCP处理可以有效地保持果实水分含量,延缓果实硬度下降,保持果实中VC含量。1-MCP处理的蓝莓果实颜色比对照果实颜色浅,能够延缓果实贮藏前期的花青苷形成。另外,1-MCP处理抑制了果实贮藏后期总抗氧化能力的下降,维持了果实较高的营养价值。     

冰温和自发气调袋贮藏对冬枣质构及生理特性的影响

本文以成熟冬枣为试材,选取冰温贮藏和自发气调袋贮藏两种方式,测定贮藏过程中的硬度、弹性、粘性、内聚性和咀嚼性等质构特性,并进行贮藏相关生理指标的测定。结果表明,冰温贮藏可以延缓冬枣果实的硬度、粘性和弹性的下降,延缓冬枣质构的衰变,同时降低可溶性果胶含量,从而抑制冬枣果实的软化。自发气调袋处理的果实其质构特性明显优于对照果实,且冬枣果实在贮藏过程中失重率明显低于对照和冰温贮藏的冬枣果实。对照果实,冰温处理和自发气调保鲜袋处理的冬枣果实贮藏至20 d时,失重率分别为12.02%,10.25%和1.17%。自发气调保鲜袋处理可以延缓冬枣果实的Vc含量下降,保持果实较高的营养品质。冰温贮藏能够延缓果皮花青苷的形成,贮藏20 d后红色果皮部分不到1/3,而自发气调保鲜袋处理的果实花青苷会正常合成。自发气调袋处理的效果优于冰温贮藏。     

水杨酸处理对杏果实贮藏品质的影响

研究了水杨酸处理赛买提杏后对其采后贮藏品质的影响。在0.05MPa负压下,将杏果实分别浸泡于浓度为0.002、0.01、0.05g/L的水杨酸溶液中。将处理后的杏果实取出晾干,于4℃,RH90%～95%条件下贮藏。定期测定杏果实贮藏期间的失重率、硬度、叶绿素、维生素C、可溶性固形物、可滴定酸、发病率。结果显示,0.01g/L水杨酸处理的杏果实贮藏品质最好,能有效地抑制杏果实贮藏期间的失重率上升,硬度的下降,延缓叶绿素和维生素C含量的下降,减少杏果实中可溶性固形物和可滴定酸的损耗,降低杏果实腐烂率。     

1-甲基环丙烯(1-MCP)真空渗透处理对货架期杏果实采后生理和品质的影响

火村红杏果实经1-甲基环丙烯(1-methylcyclopropene,1-MCP)真空渗透处理后,于0℃贮藏2周再转到货架期(23～25℃)贮藏.研究结果表明:1-MCP处理能有效地抑制货架期杏果实呼吸强度和乙烯释放量,延缓果实硬度、可滴定酸和抗坏血酸含量的下降,抑制类胡萝卜素的合成积累和推迟果实色泽的转变.采后1-MCP处理明显延缓了货架期杏果实后熟软化,使果实的品质和风味更加突出.     

不同中药提取物对“夏黑”葡萄保鲜效果的影响

以"夏黑"葡萄果实为试验材料,探讨桑叶、丁香、广藿香和复方桑叶提取物处理对"夏黑"葡萄果实采后生理及贮藏品质的影响。结果表明,与对照组相比,桑叶、丁香、广藿香和复方桑叶提取物处理均可不同程度地延缓葡萄果实中多酚含量、TSS含量和VC含量的下降速度,较好地保持了葡萄果实的贮藏品质。其中,经过桑叶处理的葡萄果实中多酚、TSS和VC含量降低最少;经过复方处理的葡萄果实腐烂率下降最缓慢,有效地保持了葡萄的风味。     

CARAMBOLA QUALITY AFTER HEAT TREATMENT,COOLING AND STORAGE1

Various cooling methods following heat treatment were investigated to reduce injury to carambola (Averrhoa carambola L.) caused by heat stress. Cooling fruit with ice water (IW) caused more severe degradation to carambola quality compared with ambient air (AA), ambient water (AW) or refrigerated air (RA). Cooling fruit after heat treatment with RA at the targeted storage temperature (10C) resulted in the least damage to carambola. Refrigerated air, AA, and AW caused similar degradation such as peel pitting, bronzing, decay and weight loss, but AA cooled fruit were the least firm, and AW cooled fruit had the least preferred flavor. At the end of 7 days of storage, fruit heated with hot water (HW) were less yellow than vapor heat (VH)‐treated fruit, and fruit cooled by AA were more yellow than those cooled by other methods. There was no difference in peel color, total soluble solids, titratable solids, pH, or mastication texture of pulp among treatment combinations. Carambolas cooled with refrigerated air had the least injury compared with other cooling methods evaluated.     

Browning Susceptibility and Changes in Composition During Storage of Carambola Slices

Browning and changes in the composition of sliced and whole carambola (Averrhoa carambola L.) fruit during storage were investigated. Susceptibility to browning after slicing, packaging and storage for 4 wk at 4.4°C varied considerably between four cultivars and five selections. There was no difference in browning susceptibility between fruit harvested at mature green or breaker stages of maturity. Freshly sliced carambola browned only slightly when exposed to air, but packaged slices that had been stored for 2 or more wk at 4.4°C browned rapidly (within 6 hr) when exposed to air. Whole fruit stored at 4.4°C for up to 6 wk, then sliced, showed much less susceptibility to browning. Ascorbic acid decreased and polyphenoloxidase activity increased in carambola slices during storage, but less in whole fruit. Treating slices with 1.0 or 2.5% citric acid + 0.25% ascorbic acid (in water) prior to packaging was very effective in limiting browning.     

Changes in selected quality characteristics of minimally processed carambola (Averrhoa carambola L.) when treated with ascorbic acid

‘B 10’ carambola of ripening stage (RS) 3 and 4 were minimally processed (MP) and then dipped in 0, 15 and 30 mg L^?1 ascorbic acid (AA). The 1‐cm‐thick slices were then dried, packed into cling‐wrapped‐foam tray and stored at 7 °C for 0, 3 and 5 days. Skin colour (L*, C* and h°), flesh firmness, soluble solids concentration, vitamin C content, titratable acidity, pH, degree of browning, polyphenoloxidase (PPO) activity and sensory attributes of MP carambola treated with AA were determined. AA treatment had significant effect in decreasing cut surface browning degree but no significant effect on all the selected quality characteristics of the MP carambola. In the sensory evaluation, flesh colour, sweetness, flavour and overall taste were significantly affected by AA treatment especially at 15 mg L^?1. The RS of fruit significantly affected skin colour (C* and h°), pH and sensory attributes of colour and flavour of the MP carambola. As storage day (SD) progressed, skin colour (C* and h°), flesh firmness and vitamin C content, cut surface browning, PPO activity and all the sensory attributes of MP carambola decreased significantly. Flesh firmness of the MP carambola was affected by the interaction between AA × SD. Sensory attributes of MP carambola were affected significantly by AA × RS. All the sensory attributes of MP carambola positively correlated to each other but negatively correlated with browning degree. PPO activity positively correlated with browning degree. Copyright © 2007 Society of Chemical Industry     

壳寡糖对杏果实贮藏品质的影响

以新疆赛买提杏为原料,选用分子量5000u、浓度为1.00%、0.50%、0.25%的壳寡糖对杏果实进行减压渗透处理。处理后的杏果实放置在温度为4℃、相对湿度90%～95%的冷库中贮藏,定期测定杏果实的品质指标,研究壳寡糖处理对杏果实贮藏品质的影响。实验结果表明,浓度为0.50%的壳寡糖处理效果最好,可有效地保持杏果实的硬度和叶绿素的含量,延缓抗坏血酸和可滴定酸含量降低以及可溶性固形物含量的上升,降低杏果的呼吸强度,抑制杏果实的发病率。     

褪黑素结合丁香酚处理对红桃贮藏品质的影响

为研究褪黑素结合丁香酚处理对桃贮藏品质的影响,本实验以镇远红桃为试验材料,采用不同的处理（0.5 mmol/L褪黑素处理;50μL/L丁香酚处理;0.5 mmol/L的褪黑素+50μL/L的丁香酚处理）对桃浸泡5 min,处理后自然晾干在温度（0.5±0.5）℃条件下进行贮藏,研究贮藏期桃品质变化。结果表明：褪黑素结合丁香酚的处理能有效地降低果实腐烂率和呼吸强度,延缓硬度、可溶性固形物含量、可滴定酸含量和总酚含量的下降,有效维持SOD活性、APX的活性和PPO的活性。在贮藏期60 d时,褪黑素+丁香酚组果实腐烂率仅为14.65%,而CK组、褪黑素组、丁香酚组的果实腐烂率分别为36.72%,25.63%,22.49%。综上所述,褪黑素结合丁香酚处理能够推迟桃贮藏期的衰老进程,抑制果实品质的下降,更好地保持贮藏品质。     

Changes in quality attributes of pulsed light and thermally treated mixed fruit beverages during refrigerated storage (4 °C) condition

The effect of batch pulsed light (PL) irradiation (3000 J cm⁻²) on the shelf-life of the beverage blend comprising apple ber (Indian jujube), carambola (star fruit), and black table grapes was investigated. The equivalent thermally treated beverage (90 °C|5 min) exhibited greater stability from microbial and enzymatic spoilage but retained 27% less antioxidants and 14% less vitamin C than PL-treated juice. Thermally and PL-treated blends possessed sensory scores of 5.8 and 7.2, respectively. The beverage's microbial shelf-life (population ≤ 6-log₁₀ cfu/mL) was extended to 45 days at 4 °C after the PL treatment. The PL exposure did not alter the pH and soluble solids during storage. The PL-treated juice, after 45 days, was placed on par with the freshly prepared juice by the sensory panel. The PL-treated juice preserved 61% more antioxidants, 38.8% more phenolics, and 68.2% more vitamin C than the thermally pasteurized beverage after 45 days of refrigerated storage.Industrial relevanceWhile the fruit processing industry demands microbial safety and enzymatic stability, today's consumer demands juices of high nutritional quality. This study utilizes under-explored fruits like apple ber (Indian jujube) and carambola (star fruit) to make a shelf-stable mixed fruit beverage. This study will help the industry understand the potential of PL treatment in accomplishing microbial safety, enzymatic stability, and nutritional quality, along with the utilization of under-explored fruits.     

CO2高渗袋复合处理对“金桃”猕猴桃贮藏品质的影响

为研究CO2高渗袋(high carbon dioxide permeability film bag,GS)、1-甲基环丙烯(1-methylcyclopropene,1-MCP)和乙烯吸收剂(ethylene absorbent,EA)对“金桃”猕猴桃的保鲜效果,以“金桃”猕猴桃为试材,研究3种保鲜方法单一或复合处理对“金桃”猕猴桃贮藏期间果实硬度、可溶性固形物(total soluble solid,TSS)含量、维生素C(vitamin C,VC)含量、淀粉含量、呼吸强度和丙二醛(malondialdehyde,MDA)含量的影响。结果表明:各保鲜处理均能不同程度延缓“金桃”猕猴桃的果实硬度、VC含量、淀粉含量下降,抑制TSS含量、呼吸强度升高,减少MDA含量的累积。其中,GS+1-MCP+EA处理保鲜效果最好,贮藏180 d时,果实硬度、VC含量和淀粉含量最高,分别为0.93 kg/cm2、99.84 mg/100 mL和29.50 mg/g,TSS含量、呼吸强度和MDA含量最低,分别为13.40%、16.49 mg/(kg·h)、1.04 mmol/g,且这些指标与对照均差异显著(P<0.05)。     

石榴贮藏期间间歇升温处理对果实品质的影响

以陕西临潼净皮甜石榴为试材,研究了间歇升温处理对石榴果实贮藏期间品质变化的影响。结果表明:石榴在(5.0±0.5)℃条件下贮藏,每隔6 d在(15±0.5)℃下间歇升温处理24 h,能有效保持果粒可溶性固形物含量、总糖含量和可滴定酸含量,减缓果皮褐变指数升高速率,降低果实腐烂率,贮藏120 d果实外观色泽鲜艳.籽粒感官品质良好,保鲜效果理想。     

超高压处理对杨梅鲜果感官品质的影响

为了探讨超高压处理对杨梅鲜果感官品质的影响,将杨梅("东魁"品种)鲜果在400～600MPa压力、室温条件下处理2min后,测定鲜果在25℃和4℃条件下储藏期间的感官品质变化,包括颜色、汁水流失、硬度、糖度、pH等指标的变化。结果表明:不同条件超高压处理后,样品的颜色、糖度、pH在储藏期间没有显著变化,汁水流失随着储藏时间的延长不断增大,鲜果硬度随着储藏时间增大而减小。不同超高压条件对杨梅鲜果的感官品质影响不显著。与未处理的鲜果品质变化速率对比,超高压处理后的鲜果品质变化速率显著减小,说明超高压处理可以有效延缓杨梅储藏期间的品质变化。