TPA质构分析栽培料水分对草菇子实体采后质地变化的影响

研究不同草菇栽培料含水量对草菇采后保鲜的影响,从栽培料水分的角度,为研究草菇采前保鲜提供理论依据.采用生产草菇常用原材料(废棉90％和棉籽10％),设置培养料高水分(73％)和低水分(63％)2个梯度栽培草菇.将草菇采后置于温度15℃,湿度55％的环境中贮藏,结合表型和质地多面分析法,研究栽培料水分高低对草菇采后贮藏的...     

基于质地多面分析法对平菇质构特性的分析

以平菇108-2、108-3及108-9 3个供试菌株为试材,采用感官评价和质构仪质地多面(TPA)分析法,研究发酵料及发酵熟料2种栽培模式对平菇子实体不同部位质地参数的影响,以期为平菇子实体质构分析和平菇育种提供参考依据。结果表明：不同模式下子实体质地特性差异主要是由品种决定;TPA质地参数可以代替感官品质评价,菌柄的质地参数大多高于菌盖;利用多元统计分析(主成分分析和相关性分析)能够提取到4个主成分,累计方差贡献率达到79.54%,其中硬度、咀嚼性及内聚性3个参数可用来反映平菇子实体质地特性。     

质地多方面分析三个桃品种果实采后质地的变化

以鲜食桃品种"脆保"、"艳保"和"大久保"为试材,采用质构仪质地多方面分析测试法(TPA),研究3个品种果实采后不同贮藏时间的质地变化。结果表明:在室温和低温2种贮藏温度下,3个品种桃果实的硬度随着贮藏时间的延长逐渐下降,而粘附性、弹性、咀嚼性都随贮藏时间延长呈现先上升后下降的趋势,表现为"脆保""艳保""大久保";内聚性变化相对比较平缓。相关性分析表明,桃果实咀嚼性与粘附性呈极显著正相关,二者与果实硬度间亦表现为极显著正相关(P0.01)。弹性与硬度和咀嚼性之间均呈相反的线性相关关系,果肉内聚性值与其它参数值相关性较差。硬度、粘附性、弹性和咀嚼性可用于评价采后桃果实质地的变化,内聚性则反映了果实质地的细微变化。     

不同贮藏温度对‘红香酥’梨果实品质和相关生理指标的影响

以山西省运城市盐湖区的‘红香酥’梨果实为试材,研究了-1.5、-0.5、0.5、1.5、3.0℃5个低温环境下‘红香酥’梨贮藏120、180、240 d以及对应的20℃货架7 d的果实外观品质和内在品质、呼吸强度和乙烯释放量等相关生理指标的变化规律,以确定‘红香酥’梨最适贮藏温度和最佳贮藏期。结果表明:L值和h°可较好地反映‘红香酥’梨果实贮藏期间果皮颜色的变化情况,贮藏后期(贮藏180～240d),1.5℃和3.0℃贮藏果实的果皮颜色亮(L值高)、黄(h°低、a值负值绝对值低)、果皮油腻化、果实腐烂严重;-1.5℃贮藏虽能较好地维持果皮绿色和抑制果实腐烂,但贮藏后期果心出现严重褐变,而且果实硬度和可溶性固形物含量较低;-0.5℃和0.5℃贮藏能长期维持‘红香酥’梨较高的果实硬度和可溶性固形物含量,明显抑制果皮转黄和果心褐变,保持果实较好的食用品质和商品价值,还能更好地抑制果实呼吸强度和乙烯释放量、降低果实乙醇的积累和减轻细胞膜的损伤程度。建议‘红香酥’梨中短期(120d以内)贮藏温度以1.5～3.0℃为宜,不宜太高;中长期贮藏(120～240 d)可采用-0.5～1.5℃,不宜太低。     

不同浓度1-MCP处理对“早金酥”梨低温贮藏品质的影响

以"早金酥"梨为试材,经不同浓度(0.0(CK)、1.0、2.0、4.0μL·L~(-1))1-MCP处理后,放置在(0±0.5)℃条件下贮藏105d,研究其品质变化。结果表明:不同浓度1-MCP处理均显著抑制了果实乙烯的合成,降低了果实呼吸强度,较好地保持了果实中可滴定酸含量和维生素C含量,维持了果实硬度,提高了果实的品质,但对果实可溶性固形物含量的变化无明显的影响。1-MCP处理对"早金酥"梨贮藏保鲜效果显著,以2.0μL·L~(-1)的1-MCP处理效果最好。     

不同浓度1-甲基环丙烯处理对鄂北冬枣常温贮藏生理指标及品质的影响

以鄂北冬枣为试材,研究了不同浓度1-甲基环丙烯(1-MCP)处理(500、1 000、1 500nL/L)对鄂北冬枣采后生理指标及贮藏品质的影响。结果表明:在常温条件下贮藏21d时,1-MCP处理能够延缓冬枣在贮藏过程中硬度、可滴定酸含量和维生素C含量的下降,提高可溶性固形物含量,降低果实的呼吸速率,其中以1 000nL/L保鲜效果最佳。     

留树保鲜对恭城水柿果实品质、贮藏特性及翌年果实产量和品质的影响北大核心CSCD

【目的】探讨激素和叶面肥喷施对留树保鲜水柿的果实品质、贮藏特性及翌年产量和品质的影响,为水柿果实留树保鲜提供理论依据和技术指导。【方法】在花后170~214 d每隔7~15 d分别喷施75%的GA_(3)50000倍液、0.01%2,4表芸薹素内酯2800倍液及可溶性叶面肥800倍液3次(处理Ⅰ)、4次(处理Ⅱ)和5次(处理Ⅲ),同时增施0.5%的尿素和0.5%磷酸二氢钾作为追肥,以成熟后自然挂果、不增加追肥量的植株作为对照,比较不同处理对不同采摘时间果实的色泽、营养成分含量、果实质地及贮藏特性的影响,并探讨留树保鲜措施对翌年果实产量和品质的影响。【结果】激素和叶面肥喷施导致果实色泽转变和营养成分转化延迟,减缓水柿硬度、弹性、内聚性、咀嚼性的下降,且处理组的果实在贮藏期营养成分含量和质地的下降相比对照组更缓慢,其中喷施混合液3次(处理Ⅰ)的延缓效果更为显著。同时与对照组相比,处理组延迟采收后植株翌年的果实产量、果实大小和优质果率并无显著差异。【结论】留树保鲜技术能有效延迟水柿果实的成熟,且不会对果实品质、贮藏特性和翌年的产量、品质造成影响。因此,在近成熟期喷施3次GA3、表芸薹素内酯和可溶性叶面肥是水柿留树保鲜最经济有效的方案。     

Study and prediction of quality changes in garlic cv. Perla (Allium sativum L.) stored at different temperatures

White and purple garlic is harvested in the Bajio region of Mexico from February to August and then stored at room temperature. A complete study of quality changes under different conditions and how these conditions interact to determine the shelf life of the product has been lacking, nor have objective parameters to predict shelf life been determined. Six batches of 360 bulbs of garlic (Allium sativum L.) cv. Perla were stored for 190 days at 0 °C, 0 °C and 70% relative humidity (RH), 5, 20, 30 °C, and at room temperature (RT) (17.7 ± 7 °C). The weight loss, subjective firmness of the bulbs, clove penetration resistance, hue value, internal sprouting index, soluble solids and dry matter content of the cloves were recorded periodically. The weight loss and internal sprouting index had a negative correlation on the subjective firmness, penetration resistance, and hue of the cloves. Storage at 5 °C, 20 °C, and RT induced sprouting, and subsequent growth had an effect on a loss of firmness and color. Complete sprouting (>100%) induced a weight loss of 9–11% at these temperatures. In order to maintain an adequate safety margin for marketing, we propose an internal sprouting index of 50% to determining the effective shelf life of garlic cv. ‘Perla’. In accordance with this criterion and in conditions studying, shelf life at 0 °C was 155 days; at 5 °C and RT it was 80 days; and at 20 °C it was 60 days. These results lead us to conclude that it is possible to estimate the shelf life of garlic using the internal sprouting index.     

Effects of greenhouse cooling method on growth,fruit yield and quality of tomato (Solanum lycopersicum L.) in a tropical climate

A tomato (Solanum lycopersicum L.) crop was grown in four greenhouses during the dry season 2005/06 in Central Thailand. Sidewalls and roof vents of two greenhouses were covered with nets and these greenhouses were mechanically ventilated when air temperature exceeded 30 °C (NET). The other two greenhouses were covered with polyethylene film and equipped with a fan and pad cooling system (EVAP). Overall mean air temperature was significantly reduced by 2.6 and 3.2 °C (day) and 1.2 and 2.3 °C (night) in EVAP as compared to NET and outside air, respectively. Temperature maxima in EVAP averaged about 4 °C lower than in NET and outside. The relative humidity was around 20 and 30% (day) and 10 and 15% (night) higher in EVAP than in NET or outside, respectively. Vapour pressure deficit averaged 0.25 kPa in EVAP, 1.03 kPa in NET and 1.48 kPa outside. The crop water-consumption was significantly lower in EVAP (1.2) than in NET (1.8 L plant⁻¹ day⁻¹), which is ascribed to reduced transpiration in EVAP. Total fruit yield was similar in NET (6.4 kg plant⁻¹) and EVAP (6.3 kg plant⁻¹). The quantity of undersized (mostly parthenocarpic) and blossom-end rot (BER)-affected fruits was reduced in EVAP. However, the proportion of marketable yield was significantly higher in NET (4.5 kg plant⁻¹) than in EVAP (3.8 kg plant⁻¹), owing largely to an increased incidence of fruit cracking (FC) in EVAP. Higher FC but lower BER incidence coincided with higher fresh weight and Ca concentration in the fruits in EVAP. It is concluded that in regions with high atmospheric relative humidity evaporative cooling without technical modifications allowing dehumidification will not improve protected tomato production.