1-MCP对灵武长枣采后生理变化的影响

以灵武长枣为试材,采收后经1—MCP（1-甲基环丙烯）处理,在0℃条件下贮藏,定期测定果实品质和生理生化指标,以期研究对其贮藏效果的影响。结果表明,1μL/L1-MCP处理可以显著地保持果实硬度,抑制VC含量、可滴定酸含量和失重率的下降。0℃条件下贮藏90天时,果实硬度达6．5kg／cm^2,VC含量为253．9mg／100g,可滴定酸含量为0．275％,失重率4．9％;显著地降低PPO和ADH活性,贮藏末期分别为1．287U和22．0U;延迟灵武长枣果实的后熟与衰老,低温贮藏90天后好果率达到75．5％。     

壳寡糖处理对天麻贮藏品质的影响

天麻采收后分别用0．5％、1．5％、3．0％壳寡糖溶液浸泡处理40～50min,在常温条件下（25℃）贮藏180d,研究壳寡糖处理对天麻贮藏品质的影响。结果表明。经壳寡糖处理的天麻还原糖含量显著高于对照;过氧化氢（H202）及丙二醛（MDA）含量较对照低;过氧化氢酶（CAT）及过氧化物酶（POD）活性下降减慢;天麻素含量高于对照。表明壳寡糖可通过提高果实抗氧化防御系统的能力来延缓天麻衰老．保持其良好品质,其中以1．5％浓度的壳寡糖处理效果最佳。     

草莓保鲜前景广技术方法有讲究

采前处理草莓是非跃变呼吸型果实．含水楚高、皮薄,极易受损伤而腐烂变质,因此不耐贮臧与运输,通常贮藏期为1～2天,严重地限制了销售和加工。草莓采后的硬度决定了果实贮藏时间的长短。一般草莓采后硬度下降很快,高CO2、低O2和气调均可不同程度地保持硬度一此外,用0．5％乳酸钙或0．5％乳酸钙 1％柠檬酸浸果和脱乙酰甲壳涂膜均可保持果实的硬度。     

不同保鲜剂组合处理对草莓保鲜效果的影响

以全明星草莓为试验材料,研究CaCl2、植酸、柠檬酸和山梨酸钾不同浓度的复配组合及其结合壳聚糖涂膜处理对常温（20～25℃）条件下贮藏7d草莓果实品质的影响。结果表明,对在常温条件下草莓采后保鲜的最佳复配组合为：1％CaCl2＋0．15％植酸＋2％柠檬酸＋0．1％山梨酸钾。该复配保鲜剂再与l％壳聚糖制成涂膜,在抑制草莓果实腐烂,保持果实硬度,延缓可溶性固形物和VC含量下降方面的作用效果好于单纯复配保鲜剂。     

壳聚糖复合涂膜保鲜剂对采后青圆椒保鲜效果的研究

为延长青圆椒的贮藏时间,采用正交试验法研究壳聚糖、柠檬酸、氯化钙复合涂膜对青圆椒的保鲜效果,并进行验证,筛选出较优的壳聚糖复合涂膜保鲜剂质量浓度组合。结果表明,贮藏期间,氯化钙是影响青圆椒质量损失率、可滴定酸含量、可溶性固形物（TSS）含量的主要因素,柠檬酸是影响青圆椒VC含量的主要因素。10 g/L壳聚糖,15 g/L柠檬酸,15 g/L氯化钙为复合涂膜保鲜剂较优组合,该复合涂膜保鲜剂可减轻青圆椒果实软化程度,减少其贮藏期内质量损失,延缓果实可溶性固形物、可滴定酸、VC等营养物质的消耗及叶绿素的下降速度,抑制酚类物质含量的下降,维持较高的抗氧化活性,具有较好的保鲜效果。     

钙处理对红江橙采后贮藏品质影响的研究

研究了采后钙处理对室温条件下贮藏红江橙品质的影响。结果表明,不同浓度钙离子对红江橙的品质特性均有不同的影响。4．0％CaCl2溶液处理抑制了红江橙过氧化物酶（POD）及多聚半乳糖醛酸酶（PG）的活性,促进了过氧化氢酶（CAT）活性的提高,保护了细胞组织结构、减轻了脂质过氧化程度、延缓了果实的衰老,从而使其呼吸强度、电导率明显降低。可溶性固形物、可溶性总糖、VC含量的下降速度及总酸度的上升得到抑制,其营养物质量明显高于对照组;红江橙果实的硬度、失重率、腐烂率得到了较好的控制,有效地降低了其腐烂速度,90天时腐烂率仅为7．51％．贮藏保鲜效果明显。     

辽西大枣减压贮藏及其生理生化的研究

以大平顶大枣、赞皇大枣、金丝小枣为试材,采用减压贮藏方法,在-1℃条件下,将金丝小枣和赞皇大枣的贮藏期延长至90天以上,将大平顶枣的贮藏期延长至60天以上,且保持较好的感官品质、新鲜度及85%以上的好果率.生理生化测定结果表明,减压能进一步减缓硬度、可溶性固形物、可滴定酸、VC及还原糖的变化速度,同时可抑制果胶酶、VC氧化酶活性,延缓果实衰老过程,延长贮藏期限,提高了保鲜效果.     

速冻低温保鲜处理对鲜切甘蓝品质的影响

以鲜切甘蓝为试材,用0.3%异VC+0.3%柠檬酸浸泡护色20 min,在1%柠檬酸+1%VC溶液中漂烫(65℃)1 min,然后分别在-20℃、干冰和-60℃温度下速冻后于-18℃或0℃条件下贮藏20 d,研究不同速冻与低温保鲜处理对鲜切甘蓝贮藏品质的影响。结果表明,经护色和漂烫后采用干冰速冻处理,于0℃下贮藏20 d,鲜切甘蓝仍能够较好地保持叶绿素、VC和还原糖等营养品质,抑制腐败微生物生长,具有良好的硬度、胶黏性、弹性、咀嚼性、回复性等质构特性,色泽正常,气味清香,其感官品质显著好于其他处理。     

园黄梨气调贮藏研究初报

研究了气调指标对园黄梨贮藏效果的影响。结果表明，气调贮藏可抑制梨果实呼吸作用，减少果实消耗，保持硬度，并有利于提高果实品质。适宜的气体组合可延缓果实衰老，防止果实褐变且延长贮藏期。5％O2＋0％～1％CO2是长期贮藏园黄梨的理想气体指标。     

切割方式与钙处理对沂州木瓜保鲜品质的影响

以沂州木瓜为原料,采用不同浓度氯化钙处理及不同的切割方式对沂州木瓜保鲜品质进行了研究。试验结果表明,纵切的沂州木瓜耐贮性与品质要比横切的效果好;关于CaCl2浓度的影响与切割方式密切相关,纵切样品中,以0．4％CaCl2处理效果较好;而横切样品中,以0．6％CaCl2处理效果较好。     

白蘑菇保鲜工艺的研究

以白蘑菇为原料,采用正交试验设计优选护色剂,通过试验优选保鲜剂和贮藏温度。结果表明,0.50%柠檬酸+0.15%苯甲酸+0.15%异抗坏血酸钠抑制褐变的效果较好,抑制率可达81%;保鲜剂以0.15%焦亚硫酸钠+0.20%氯化钠+0.10%氯化钙的效果较好;贮藏温度为0℃的保鲜效果好。     

Effect of minimal processing on bioactive compounds and antioxidant activity of fresh-cut ‘Kent’ mango (Mangifera indica L.)

The influence of dipping in ascorbic acid, citric acid and calcium chloride (AA + CA + CaCl₂) solution and storage time on color, bioactive compounds content and antioxidant activity of fresh-cut mango ‘Kent’ stored at 5 °C was evaluated. The treated mangoes showed better color retention during storage than control mangoes. The dipping treatments with AA + CA + CaCl₂ significantly increased the vitamin C values compared with untreated mango cubes. β-Carotene was not affected by dipping treatments and vitamin E showed a significant decline over storage time for both treated and untreated mango cubes. However, higher vitamin E values were found in treated mangoes. Dipped cubes had higher antioxidant activity measured as TEAC and %RSA than controls. In general, addition of ascorbic acid as an anti-browning agent not only retarded quality loss of fresh-cut mango cubes but also promoted significant increases in antioxidant activity in comparison with control samples.     

柠檬酸对鸭梨贮藏后期微生物数量和品质的影响

为探讨柠檬酸对鸭梨贮藏后期的保鲜机制,以鸭梨为试材,采用不同浓度的柠檬酸溶液浸泡鸭梨果实,在4℃的条件下分别贮藏10天、20天、30天,测量了贮藏后期柠檬酸处理对鸭梨的硬度、可溶性糖、可溶性固形物以及霉菌和酵母菌的数量的变化的影响。结果表明:在试验期间,4种浓度柠檬酸浸泡处理均可在不同程度上降低果实的失重率和腐烂率,其中2%柠檬酸浸泡处理的鸭梨贮藏的效果最佳,其腐烂率和失重率分别为8.3%和18.18%,抑制了果实贮藏后期微生物数量,防止硬度、可溶性糖以及可溶性固形物含量的下降。柠檬酸处理是鸭梨贮藏后期为改善鸭梨品质和控制微生物数量的一种可选方法。     

Lettuce quality loss under conditions that favor the wilting phenomenon

While temperature management is a usual accepted practice and is the simplest and easiest way of delaying vegetable deterioration, maintenance of the recommended relative humidity (RH) during postharvest storage is not always carried out. The objectives of this work were to simulate two RH conditions: optimal (95–98%) and low (70–72%) during the storage of lettuce heads at recommended temperatures (0–2 °C), and to address how deviation of RH from optimal conditions affects lettuce quality indices. The effects of storage on quality parameters were assayed as follows: weight loss and water content as physical indices, chlorophyll content as a greenness index, native microflora (mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria, total coliforms, yeast and molds) as microbiological quality indices, ascorbic acid retention as a nutritional quality index, and overall quality as a sensory acceptability index. Additionally, these indices (with the exception of weight loss) were analyzed in three lettuce sections: external (composed by outer and older leaves), middle (composed by mid leaves) and internal (composed by inner and younger leaves). Shelf-life of lettuce was significantly affected by RH. The exposure of lettuce heads to low RH drastically reduced shelf-life by 75%. Plants exposed to low RH had considerable weight loss from the first day to the end of storage. For both RHs, the middle and internal sections did not show chlorophyll changes during storage while the external section showed pigment degradation characterized by first order kinetics. Ascorbic acid underwent first order degradation for all situations (sections and RH conditions), but with different degradation rates. The microbial population counts were slightly affected by RH. The overall quality of lettuce stored at low RH decreased rapidly. The shelf-life of material stored at this relative humidity condition was 5 days, when the overall quality scores of middle and external sections were below the acceptability limit and only the internal section had a score above the limit. In addition, overall quality of lettuce stored at optimal RH decreased slowly. At day 5 of storage the three lettuce sections had high scores and the product was satisfactory. Only at day 20 did the external section show a score just on the acceptability limit.     

Shelf life of minimally processed potatoes: Part 1. Effects of high oxygen partial pressures in combination with ascorbic and citric acids on enzymatic browning

The shelf life of minimally processed potatoes is limited by enzyme-catalysed browning reactions. Generally, this phenomenon is controlled by the use of chemical reagents such as ascorbic acid, citric acid, or 4-hexyl resorcinol, but it seems that “oxygen shock” treatments are also particularly effective in inhibiting enzymatic browning. The aim of this work was to study the effects of high oxygen partial pressures in combination with ascorbic and citric acid on the development of the enzymatic browning of peeled and cut potatoes (‘Primura’ variety) that were packaged in flexible pouches and stored at 5 °C for 10 days. Different treatments, chosen in according to a central composite design, were applied to the sliced potatoes. The browning development during storage was measured by a tristimulus colorimeter. Second-order polynomial models were computed for three periods of storage (3, 7 and 10 days) to relate the independent variables (oxygen partial pressure, ascorbic and citric acid concentrations) to the colour function attributes.The effectiveness of the statistical approach offered the possibility to investigate the effects of several processing conditions involved in the enzymatic browning of minimally processed potatoes, while the response surface methodology allowed the identification of the optimum range of the independent variables which prevented browning.     

鲜切青笋加工工艺

以鲜切青笋为原料,分别采用单因素试验与正交试验方法确定不同护色剂的最佳浓度.试验结果表明,鲜切青笋经4%柠檬酸,5%抗坏血酸,0.07%苯甲酸钠混合溶液处理10min,再利用真空包装进行贮藏,可使鲜切青笋颜色保持鲜绿,贮藏期长达7～10天.     

Combined effect of chemical treatment and/or modified atmosphere packaging (MAP) on quality of fresh-cut papaya

The efficacy of chemical dips and modified atmosphere packaging (MAP), alone and in combinations, on the quality of fresh-cut papaya were studied throughout 25 days at 5 °C. Fresh-cut papaya were dipped in a solution of calcium chloride (1% w/v) and citric acid (2% w/v), packed in an atmosphere of 5% O₂, 10% CO₂, 85% N₂ and stored at 5 °C for 25 days. Physico-chemical analysis (package atmosphere, weight loss, pH, total soluble solids, firmness and color) and microbial quality along with a sensory analysis were measured at regular intervals throughout the storage period. Significant differences were found among the chemically treated and non-treated fresh-cut papaya in all the parameters considered. Chemical treatment followed by MAP, showed the best results among the treatment in terms of retaining sensory and quality characteristics and extending the shelf-life of 25 d for fresh-cut papaya.     

Aloe vera gel coating maintains quality and safety of ready-to-eat pomegranate arils

Several postharvest treatments were performed on pomegranate arils prior to storage in rigid polypropylene boxes for 12 days at 3 °C: water (control), ascorbic + citric acids (at 0.5 or 1%), Aloe vera gel (at 50 or 100%), 50% A. vera gel + 0.5% ascorbic and 0.5% citric acid, and 100% A. vera gel + 1% ascorbic and 1% citric acid. A. vera (alone or in combination with acids) led to lower CO₂ and higher O₂ concentrations inside the packages compared with arils treated with water (control). With respect to quality attributes, A. vera coatings led to firmness retention and increased levels of total anthocyanins and total phenolics. In addition, A. vera treatments led to significantly lower counts for both mesophilic aerobics and yeast and moulds. Sensory analysis scores for flavour, texture, aroma, colour and purchase decision were higher in arils treated with A. vera, especially in those arils treated with 100% A. vera + 1% ascorbic and citric acids. Finally, no off-flavours in pomegranate arils were perceived by judges as a consequence of A. vera gel treatment.     

1-MCP和乙烯脱除剂对嘎啦苹果贮藏生理及品质的影响

以嘎啦苹果为试材,研究1－MCP与乙烯脱除剂不同处理对0℃贮藏180d的果实生理与品质变化的影响。结果表明,1－MCP处理可较持久地抑制果实的乙烯合成,进而抑制果实的呼吸作用,延缓衰老,保持果实品质,其中,1．0μL．L^-1浓度1-MCP处理的嘎啦苹果可贮藏180d,0．5μL·L^-1浓度的1-MCP处理可贮藏150d：乙烯脱除剂处理在贮藏前期对抑制果实乙烯合成、延缓衰老也有较好的作用．其中MA＋2袋乙烯脱除剂处理可贮藏150d,MA＋1袋乙烯脱除剂处理可贮藏120d;对照果实（MA贮藏）衰老较快．0℃条件下仅能贮藏90d。     

Low dose gamma irradiation does not affect the quality,proximate or nutritional profile of ‘Brigitta’ blueberry and ‘Maravilla’ raspberry fruit

Blueberry (Northern Highbush, cv ‘Brigitta’) and raspberry (cv ‘Maravilla’) fruit were subject to low dose gamma irradiation (0, 150, 400 and 1000 Gy) and stored at 0 °C for three or ten days (blueberry) and two or seven days (raspberry) to determine the effects of irradiation on fruit quality and nutritional and proximate contents. In general, none of the irradiation doses (≤1000 Gy) significantly affected blueberry or raspberry fruit quality (overall fruit quality, colour, firmness, weight loss, TSS, TA levels or TSS/TA ratio), or the nutritional or proximate content (ash, carbohydrate, dietary fibre, energy, moisture, protein, sodium, potassium, total sugars, fructose, ascorbic acid, monomeric anthocyanin, citric and malic acids). The length of time in storage affected some fruit quality and nutritional and proximate content parameters (such as overall fruit quality, firmness, weight loss, TA levels, dietary fibre, potassium, ascorbic acid, citric and malic acids), with longer storage periods resulting in lower quality fruit, irrespective of irradiation treatment. No interaction was detected between the effects of irradiation treatment and storage time, indicating that the storage effect was consistent for all irradiation doses on both blueberry and raspberry fruit quality.