Effect of preharvest sprays containing calcium,magnesium and titanium on the quality of peaches and nectarines at harvest and during postharvest storage

Peach and nectarine trees were foliar sprayed with a formulation containing Ca²⁺, Mg²⁺ and Ti⁴⁺. Parameters related to fruit quality were evaluated at harvest, after 7–28 days of cold storage and after subsequent ripening for 4 days at 20 °C (shelf life). At harvest, treated fruits from both cultivars had higher weight and pulp firmness than control fruits, while no effect was observed for either colour, total soluble solid content (TSS) and titratable acidity (TA) or the time required to ripen on the tree. During cold storage, lower levels of weight loss, colour evolution, TSS/TA ratio and ethylene production and higher pulp firmness were found in treated peaches and nectarines compared with control fruits. Also, the storability of treated fruits was extended for up to 14 days more than that of control fruits. During ripening at 20 °C after different periods of cold storage, parameters related to ripening evolved faster in control than in treated fruits. Also, the occurrence of the climacteric peak of ethylene production was delayed and its intensity was lower in treated peaches and nectarines than in controls. Copyright © 2004 Society of Chemical Industry     

Effect of deficit irrigation on apricot fruit quality at harvest and during storage

The effect of different irrigation strategies on the fruit quality at harvest and during storage at 1 °C of 'Búlida' apricots (Prunus armeniaca L.) was studied. Irrigation treatments consisted of a control irrigated at 100% of crop evapotranspiration (ETc) throughout the season, and two deficit irrigation treatments consisting of continuous irrigation at 50% of control, and regulated deficit irrigation (RDI) at 100% of ETc during the critical periods (second rapid fruit growth and early post‐harvest) and at 25% during the rest of the season. Fruits at harvest from both deficit irrigation treatments showed higher values of total soluble solids (TSS), titratable acidity and hue angle (h°) than control fruits, whereas their diameter, fresh weight, firmness and maturity index values were similar to those in the control. During the first 10 days of the 30‐day chilling storage period, higher TSS and h° values were found in deficit irrigated fruits, whilst the other parameters were similar for all treatments. Weight loss and fungal attacks (mainly Rhizopus sp. and Monilinia sp.) during a subsequent retail sale period of 4 days at 13 °C were the lowest in RDI. Deficit irrigation was demonstrated to be commercially advantageous for keeping fruit quality, saving considerable amounts of water. Copyright © 2007 Society of Chemical Industry     

Delayed harvest and cold storage period influence ethylene production,fruit firmness and quality of ‘Cripps Pink’ apple

The effects of harvest date and cold storage period on ethylene production, fruit firmness and quality of ‘Cripps Pink’ apple were investigated. Fruit were harvested from Perth Hills and Donnybrook (Western Australia) at commercial maturity (CM), 2, 4 and 6 weeks after CM prior to 0, 45, 90 and 135 days cold storage in 2003 and 2004. Delayed harvest significantly increased ethylene production, CIE values a* and C* at both locations in 2 years. Delayed harvest and extended cold storage period increased the internal ethylene production and reduced fruit firmness, soluble solids concentration: titratable acidity (SSC:TA) ratio and reduced CIE values L*, b*, h° during both years and locations. Fruit harvested 2 weeks after CM can be cold‐stored for 90 days with acceptable fruit quality. If the fruit is intended to be sold fresh immediately in local markets, the harvest can be delayed up to 6 weeks after CM to harness substantially improved fruit colour with acceptable fruit quality.     

A novel instrument to delineate varietal and harvest effects on blueberry fruit texture during storage

BACKGROUND: Firmness is an important quality index for blueberries. It is the major factor that determines consumer acceptability, storability and resistance to injury and diseases during storage and fresh marketing. Blueberry cultivars vary in their firmness, with southern highbush cultivars usually softer than Rabbiteye blueberries. In this study, varietal and harvest effects on blueberry firmness were measured by the Firmtech II and laser air‐puff instruments. This was the first time that the laser air‐puff, a non‐contact food firmness tester, had been used for firmness testing of small fruit, such as blueberry. RESULTS: Two southern highbush cultivars (Sweet Crisp and Emerald) and two Rabbiteye cultivars (Vernon and Savory) were used for varietal effect measurement, while a Rabbiteye cultivar (Premier) that was both machine and hand harvested was used for harvest effect observation. Fifty berry samples per replicate and four replicates were tested by two instruments at harvest and after 7, 14, or 21 days of storage. The laser air‐puff tester successfully delineated the difference in firmness due to cultivar characteristics and harvest methods, as well as the firmness loss over 21 days of postharvest cold storage (4 °C). The firmness index derived from the laser air‐puff tester achieved a significant correlation with the firmness values measured by the Firmtech (R² = 0.80). A new texture index, springiness, was developed from the laser air‐puff, which largely reflects the varietal differences in elasticity of fruit. CONCLUSION: This study demonstrated the efficacy of the laser air‐puff instrument for blueberry firmness measurement. This non‐contact instrument not only provides an alternative method of firmness measurement, but also offers a new index for fruit elasticity evaluation and better texture evaluation for blueberries. Copyright © 2011 Society of Chemical Industry     

砂梨品种果实冷藏期间质地及品质差异性评价

目的:确定砂梨品质形成及劣变关键点。方法:以早生新水、沪晶梨18、沪晶梨67为试材,将成熟度一致的3个品种的梨果实于(1.0±0.5)℃、相对湿度85%～90%的冷库中贮藏60 d,每10 d测定果实品质和10个电子鼻传感器的感应值。结果:沪晶梨18和早生新水为典型的果糖积累型,沪晶梨67为山梨醇积累型,3个品种梨均为苹果酸积累型。冷藏期间,沪晶梨67可保持较高的果实带皮硬度、果肉组织硬度、脆性和咀嚼性;含有较高的葡萄糖、山梨醇和总糖含量,可滴定酸、苹果酸含量较稳定;贮藏风味浓郁,受冷藏时间调控小,耐贮性佳。沪晶梨18的果皮特性、紧实度和脆性优于早生新水,拥有较高的果糖、苹果酸含量和果糖/总糖,可保持较高的甜酸度,贮藏风味浓郁。早生新水易软化,可滴定酸含量呈急剧下降趋势,综合风味受贮藏时间调控大,不耐贮。早生新水和沪晶梨67梨果实挥发性化合物发生了明显变化,特别是氮氧化合物、甲烷、硫化物、乙醇等挥发性化合物。结论:早生新水、沪晶梨18、沪晶梨67的安全冷藏期分别为30,40,60 d。     

Physicochemical changes during strawberry development in the field compared with those that occur in harvested fruit during storage

‘Chandler’, ‘Oso Grande’ and ‘Sweet Charlie’ strawberry cultivars were harvested at four stages of color development ranging from color break to full red and stored in the dark for 8 days at 1 °C. Changes in the physical and chemical characteristics of fruit during storage were compared with those occurring during development in the field. Strawberry fruit harvested at the three‐quarters colored and full red stages continued their development and ripening during storage. However, fruit harvested at the color break and half‐colored stages did not develop like those ripened in the field. Strawberries harvested at the three‐quarters colored stage developed the same pH, acidity, soluble solids, ascorbic acid and total phenolics content during storage as the at‐harvest levels present in strawberries harvested at the full red stage. In addition, three‐quarters colored strawberries were as firm and red after storage as the full red stage fruit were at the time of harvest. Thus, strawberries harvested at the three‐quarters colored stage can be stored for a longer period than strawberries harvested full red while retaining better color and firmness. Copyright © 2005 Society of Chemical Industry     

采收成熟度对红色甜椒贮藏品质的影响

为研究不同采收成熟度对红色甜椒贮藏品质的影响,以\     

Effects of soil management systems and nitrogen fertiliser on the firmness and mean fruit weight of Cox's Orange Pippin apples at harvest

The firmness and mean fruit weight, at harvest, of Cox's Orange Pippin apples from a soil management and N fertiliser trial planted in 1972 were measured from 1979 to 1985 (excluding 1984). Trees growing in overall herbicide, or in 0.3-m herbicide-treated strips with irrigated grassed alleyways, produced significantly softer and/or larger apples than those from trees growing in unirrigated grass with narrow (0.3 m) or wide (1.7 m) herbicide-treated strips in 1982 and 1983. Both these years had drier than average summers. N fertiliser applied annually produced slightly larger and softer apples at 189 kg N ha^?1 than at 63 kg N ha^?1.     

Changes of quality characteristics of pepino fruit (Solanum muricatum Ait) during convective drying

Quality assessment of pepino fruit preserved through convective dehydration was investigated in this work. The effect of process temperature (50, 60, 70, 80 and 90 °C) on physicochemical properties, colour, non‐enzymatic browning, vitamin C, total phenolic content, antioxidant activity and firmness of the fruit were considered. When comparing the fresh with the corresponding dehydrated pepino samples, it was shown that the drying conditions resulted in important reductions of proteins and crude fibres. Discoloration of fruit was noticeable for all treatments due to effects of non‐enzymatic browning and changes in chromatic coordinates leading to a modification of the original colour. Regarding vitamin C and total phenolic content, an increase of drying temperature resulted in a considerable reduction of both initial compounds contents. Antioxidant activity showed an important decrease especially at low temperatures (e.g. 50 °C). Softening of the dried product was observed for all the treatments indicating structural modifications of the fruit due to thermal process.     

冻干甜椒贮藏过程中抗坏血酸及还原糖的变化

以冻干甜椒为材料,研究其在不同贮藏温度下抗坏血酸及还原糖含量的变化,揭示其品质变化的情况。分别采用斐林试剂比色法、固蓝盐B分光光度法测定抗坏血酸及还原糖的含量。结果表明,在贮藏期间,冻干甜椒中的抗坏血酸和还原糖含量逐渐减少,并且随储藏温度上升减少的速率增大。     

采摘时间和天气条件对菜豆保鲜品质的影响

以贵阳青棒豆作为试材,采后贮藏在(9±1)℃下,研究了不同采摘时间和天气条件对其贮藏期间失重率、腐烂率、硬度、可溶性固形物含量、呼吸速率、可溶性蛋白质、抗坏血酸、淀粉及色泽的影响。研究发现,在阴天中午采摘时贵阳青棒豆的贮藏和营养品质最佳。      

采摘时间和天气条件对菜豆保鲜品质的影响

以贵阳青棒豆作为试材,采后贮藏在(9±1)℃下,研究了不同采摘时间和天气条件对其贮藏期间失重率、腐烂率、硬度、可溶性固形物含量、呼吸速率、可溶性蛋白质、抗坏血酸、淀粉及色泽的影响。研究发现,在阴天中午采摘时贵阳青棒豆的贮藏和营养品质最佳。     

Effect of harvest time and storage conditions on almond kernel oil and sugar composition

The effect of storage for 6 months at 5 °C (80% RH) versus 20 °C (60% RH) of shelled versus in‐shell almonds was studied on early versus late harvested nuts from ‘Ferragnes’ and ‘Texas’ trees. Kernel quality characteristics, oil composition and sugar composition were determined initially and after 6 months of storage. Early harvested almonds had similar kernel weight to but higher moisture content than late harvested almonds after 6 months of storage. Early harvested almonds also had similar oil quality (based on ultraviolet absorption coefficient measurements) and oil composition but lower sugar content and modified sugar composition compared with late harvested almonds. Storage of shelled almonds resulted in kernels with higher oil content, better oil quality, similar oil composition, similar sugar content and some modifications in sugar composition compared with in‐shell stored almonds. Finally, storage for 6 months at either 5 or 20 °C resulted in lower moisture content, higher oil content, similar oil quality and composition, similar sugar content and some modifications in sugar composition compared with freshly harvested almonds. Almonds stored at 5 °C retained higher kernel weight and moisture content than almonds stored at 20 °C. © 2003 Society of Chemical Industry     

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。     

不同贮藏温度对杏梅贮藏品质的影响

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。