鲜切哈密瓜网购产品护色保鲜包装研究

以市售哈密瓜为原料,常温下,配置不同浓度的盐、糖、醋溶液对鲜切哈密瓜进行浸泡处理后,选用3种不同的薄膜进行包装,通过每两天对鲜切哈密瓜的失重、色差等指标进行测试并判断其保鲜情况。实验结果表明:不同浓度的盐、糖、醋溶液对新鲜哈密瓜的保鲜效果不同,当采用质量分数为0.7%的盐、质量分数为1.1%的醋、质量分数为0.1%的糖浸泡液进行浸泡处理并采用15FPPE薄膜进行袋包装时,对鲜切哈密瓜具有很好的保鲜效果。本实验得到的最优工艺条件能够明显延长鲜切哈密瓜在常温下的贮藏时间,从而带来可观的经济效益。     

复合保鲜剂对鲜切天麻贮藏品质的影响

目的通过探究复合保鲜剂对鲜切天麻保鲜效果的影响,为鲜切天麻采后保鲜提供参考依据。方法以鲜切天麻为实验材料,采用四因素三水平正交实验考察茶多酚、柠檬酸、抗坏血酸、壳聚糖复配对鲜切天麻感官评价的影响,以鲜切天麻感官评价为控制指标,筛选出适宜鲜切天麻的复合保鲜剂配方。结果复合保鲜剂的最佳配方为茶多酚质量分数1.25%,柠檬酸质量分数0.50%,抗坏血酸质量分数0.20%,壳聚糖质量分数0.90%。与采用清水处理相比较,该复合保鲜剂在4℃下贮藏15d,能有效维持鲜切天麻的硬度和色差L*值,延缓其天麻素和多糖含量的下降,保持鲜切天麻PPO活性和POD活性。结论复合保鲜剂能有效地保持鲜切天麻的商品价值,可用于鲜切天麻采后保鲜。     

热风真空组合干燥对黄芪品质的影响及工艺优化研究北大核心CSCD

为解决黄芪加工过程中药效成分流失问题,使用热风真空组合干燥技术加工鲜黄芪以提高干燥品质。以色泽度、总黄酮含量、干燥时间为指标,进行单因素试验,研究切片厚度、热风温度、中间转换点含水率、真空温度对黄芪品质的影响规律;使用Central-Composite响应面法和综合评分法,建立二次回归数学模型,分析获取优化工艺参数。结果表明,各影响因素对黄芪品质的影响主次顺序:真空温度>切片厚度>中间转换点含水率>热风温度。最佳工艺参数:切片厚度4.86 mm,热风温度52℃,转换点含水率35%,真空温度69℃,在此条件下色差值为9.89,总黄酮含量为0.78 mg/g,干燥时间105 min,综合评分63.69。研究结果可为黄芪的干燥加工工艺提供参考。     

去皮鲜甘蔗的护色保鲜包装研究

通过不同浓度的盐、糖、酸溶液和不同的包装材料对去皮甘蔗进行保鲜处理,常温下贮藏,观察不同处理方法对去皮甘蔗腐坏变红的影响,再根据单因素实验和正交试验来确定最佳保鲜方案。实验结果表明:当盐溶液的质量分数为0.4%,糖溶液的质量分数为0.3%,酸溶液的质量分数为0.1%,包装材料为PP/PE或PVDC/PE时,对去皮鲜甘蔗进行保鲜处理的效果相对最好。     

微孔气调包装对鲜切菠萝蜜保鲜效果的影响

目的 为探究微孔气调包装(MMAP)对鲜切菠萝蜜的保鲜效果,明确O2体积分数、CO2体积分数和打孔数的最佳处理条件。方法 本研究以菠萝蜜为原料,通过单因素和正交-模糊综合评价法,研究冷藏期间MMAP对鲜切菠萝蜜品质(菌落总数、质量损失率、可溶性固形物(TSS)、色差、可滴定酸(TA)、硬度、VC含量和丙二醛(MDA)质量摩尔浓度)的影响。结果 与对照相比,MMAP抑制了微生物生长,维持了较高TSS、TA和VC含量,减少了MDA的积累,提高了鲜切菠萝蜜的整体品质,延长货架期至少6 d。筛选出MMAP最佳处理条件:O2体积分数为5%,CO2体积分数为6%,216 cm²的打孔数为15个。结论 MMAP是一种安全、低廉、简单的保鲜技术,可有效抑制鲜切菠萝蜜在贮藏过程中组织软化、营养损失、风味变化等品质裂变问题,具有很大的工业应用潜力。     

真空预冷技术在茶树菇冷藏保鲜上的应用研究

本研究将真空预冷技术配合塑料薄膜袋包装应用于冷藏保鲜茶树菇的预处理,研究该技术对冷藏保鲜的辅助作用,并筛选出最佳预处理工艺条件。结果表明：采用真空室的真空度350Torr,真空预冷终温0℃,真空预冷时间20min,进行真空预处理并配合塑料薄膜袋包装的茶树菇比一般的冷藏保鲜效果明显更好。表现在：冷藏十天不开伞、不干缩、表面膜不脱落、失重率减少7％,呼吸强度曲线明显下移,呼吸高峰推迟2d出现,峰值降低30％,VitC保存率提高20．5％。     

肉桂精油微囊化及其在果蔬保鲜中的应用

目的以壳聚糖、海藻酸钠为壁材,以肉桂精油为芯材,采用复凝聚法制备壳聚糖微胶囊,并将其应用于水果保鲜中。方法通过光学显微镜、扫描电子显微镜、傅里叶转化红外光谱等,确定微胶囊的最佳工艺参数、芯壁比及添加质量分数,并以芒果为实验对象,研究添加不同微胶囊质量分数的壳聚糖溶液对芒果保鲜效果的影响。结果当壳聚糖/海藻酸钠质量比为1∶2,氯化钙质量分数为1%,p H值为5,戊二醛质量分数为60%,交联时间为60 min,芯壁比为4∶1时,制备形成的壳聚糖微胶囊成球效果较好;微胶囊在壳聚糖溶液中的添加质量分数为4%时,以其涂膜的芒果保鲜效果最佳。结论肉桂精油经囊化后有效减少了气味、延缓了挥发,在果蔬保鲜中有较重要的现实研究意义。     

紫外线杀菌技术在鲜切果蔬保鲜中的应用研究进展

目的 通过介绍紫外线杀菌技术在鲜切果蔬保鲜中的应用研究进展,以期为其在鲜切果蔬保鲜中的进一步研究与应用提供参考.方法 综述国内外长波紫外线、中波紫外线和短波紫外线对鲜切果蔬品质、生理代谢相关酶活性以及微生物的影响.结果 紫外线杀菌技术作为一种绿色安全的鲜切果蔬保鲜技术,可以有效抑制鲜切果蔬中微生物的生长繁殖,减缓鲜切果蔬生理代谢,防止褐变,延迟衰老,并延长鲜切果蔬货架期,且不会对鲜切果蔬的风味和口感产生影响.结论 在目前重视食品快捷和安全的趋势下,紫外线杀菌技术因其具有安全方便、对环境友好等特点,现已在鲜切果蔬保鲜中得到广泛应用,并具有重要的发展前景.     

RDX/Al/AP/HTPB炸药回收过程中AP提取工艺的响应面法优化

为了回收RDX/Al/AP/HTPB炸药中的高氯酸铵(AP),通过Design Expert 8.0软件进行了响应面实验设计,得出了该工艺的提取率模型,研究了提取时间、超声功率、表面活性剂质量分数等因素对AP提取过程的影响。分析数据得出AP提取工艺的最佳参数,并对其进行了实验验证。结果表明,二次回归模型的拟合方程为:Y=89.82+3.10A+2.65B+0.33C-0.25AB-0.45AC-0.15BC-0.06A2-1.31B2-0.26C2。各因素对提取率的影响程度由大到小为:提取时间、超声功率、表面活性剂质量分数。优化的工艺参数为:提取时间44 min,超声功率960W,表面活性剂质量分数1.7%,此时AP的提取率达90%以上。     

保湿杀菌剂对生菜保鲜的影响

为了解决新鲜生菜在销售贮藏过程中色泽、质感、营养成分等品质迅速下降的问题,利用明胶和薄荷精油制备不同质量分数的保湿杀菌剂对生菜进行保鲜处理。每天定时测定生菜的质量、可溶性糖含量、色差、可滴定酸含量、菌落总数、VC含量,研究不同质量分数的保湿杀菌剂对生菜的保湿杀菌效果。研究结果表明:质量分数为9%的保湿杀菌剂对新鲜生菜的保鲜效果最好,其质量、可容性糖含量、色泽、VC含量变化较少,菌落总数增长较缓慢。     

Effects of processing on nutritional composition and quality evaluation of candied celeriac

In this work, a new candying procedure with partial re-use of sugar syrup is proposed. Physicochemical analysis, together with sensory evaluation, of candied celeriac samples was done. Candying was performed in a pilot unit at 65‡C, through three cycles of 5 hours duration each. Sugar syrups of 75‡ Brix were used. Effects of 1 % (m/v) citric and 1 % (m/v) ascorbic acid addition, as well as the drying of candied celeriac (60‡C for 8 h) were studied. Sugar syrup deterioration was estimated by the concentration of hydroxymethylfurfural. The results obtained showed that there were no significant(P < 0.01) differences in total dry matter and total sugar content between samples, while the increases after drying were significant(P > 0.01). Differences were observed in sugar compositions between samples. After three cycles, samples turned lighter, with decreasedL* values after drying. The celeriac from the first cycle of the ascorbic acid addition procedure was adjudged best with respect to all quality parameters. The decreased concentration of hydroxymethylfurfural confirmed that re-use of sugar syrup is possible.     

鲜切山药的抗菌处理及保鲜包装研究

针对鲜切山药在包装储存过程中容易褐变变质的缺点,用实验室中的食盐、白糖、白醋对鲜切山药进行浸泡处理,采用单因素试验和正交试验的方法寻找一种最优配比的复合浸渍液处理山药;同时用3种改性PE膜对鲜切山药进行包装,研究不同改性PE膜对鲜切山药的保鲜效果。研究表明:采用食盐、白糖、白醋质量分数分别为0.6%,0.4%,0.4%的复合浸渍液浸泡山药15 min,并用PP/PE膜包装,山药的保鲜效果最好。     

Use of Sodium Lactate and Modified Atmosphere Packaging for Extending the Shelf Life of Ready‐to‐Cook Fresh Meal

In this work, the combined effects of sodium lactate and modified atmosphere packaging (MAP) in extending the shelf life of a ready‐to‐cook fresh skewer, made up of raw pork chops and semi‐dried vegetable mix (i.e. zucchini, peppers and tomatoes), were investigated. In the first experimental step, a sodium lactate solution was used to dip pork chops at three different concentrations: 20, 40 and 60% w/w. The second part of the work was focused on the use of MAP. In particular, the following MAPs were tested: MA1 (50%O₂/30%CO₂/20%N₂), MA2 (70%O₂/30%CO₂), MA3 (30%O₂/70%CO₂) and MA4 (30%O₂/30%CO₂/40%N₂). Finally, the optimal concentration of sodium lactate and the best gas composition were combined. The samples were stored at 4 °C; their microbial and sensory qualities were monitored along the entire observation period. The results indicate that the shelf life of the investigated ready‐to‐cook meal can be extended by approximately 83%, if compared with the control skewer packaged in air. The best preservation strategy is the combination of dipping of meat pieces in 40% sodium lactate solution and packaging under MA1. Copyright © 2014 John Wiley & Sons, Ltd.     

生物调节保鲜膜对山药/大蒜组合的保鲜包装研究

使用生物调节膜包裹山药和大蒜,并利用大蒜的杀菌性能抑制山药储存期间微生物的生长,对新鲜山药常温下的保存效果进行了研究。主要测试了储存过程中的失重率、微生物、VC、糖度、硬度等参数。通过对实验数据的测定和分析,以及对实验的观察,发现大蒜对抑制微生物生长的效果很明显,且能有效降低山药的失重率,减缓糖度、VC和硬度的下降速度,有效延长山药的保鲜期。通过对山药和大蒜比例的实验,发现150g山药保鲜包装中添加3~4颗(约4~5 g)大蒜时,抑制微生物生长的效果最好。     

Optimization of sodium sulfide treatment of rice straw to increase the enzymatic hydrolysis in bioethanol production

The efficiency of sodium sulfide-assisted alkaline pulping for cellulose preparation from Oryza sativa L. rice straw in Vietnam for enzymatic saccharification was investigated. The response surface methodology was used for the determination of optimal technological parameters of alkaline pulping such as active alkali dosage, temperature and time. The optimal technological parameters were established to be active alkali dosage of 7%, treatment temperature of 100 °C and treatment time of 120 min. At these regimes, a maximal sugar yield of 51.8% (over dry rice straw) was obtained. It meant that the saccharification efficiency up to 97.1% could be achieved by using sodium sulfide-assisted alkaline pretreatment method. Addition of sodium sulfide into alkaline pretreatment resulted in higher sugar yield, higher level of depolymerization of lignin and less loss of cellulose. Moreover, liquid hydrolyzate after enzymatic hydrolysis was analyzed by HPLC to determine the compositions of sugar mixture. The fiber morphology in pretreated biomass solid was also revealed by SEM.     

气调包装对冷鲜禽肉感官特性和保质期的影响

目的研究CO组、无氧组、真空组、低氧组、高氧组、普通组等6种包装方法对冷鲜禽肉感官特性和保质期的影响。方法测定禽肉在贮藏不同时间后的感官特性、理化指标(pH值、TVB-N值、TBA值、汁液损失率)和菌落种数的变化。结果随着贮藏时间的增加,各组的感官特性呈现下降趋势,CO组感官指标较好,12 d时保持新鲜;理化指标和菌落总数整体呈上升趋势,CO组、无氧组和真空组上升较慢,保持新鲜9~12 d。结论 CO组、无氧组和真空组保鲜效果较好,保鲜期达12 d,添加了CO(0.5%)对禽肉的感官特性有明显效果,总体保鲜效果为CO组无氧组真空组低氧组高氧组普通组。     

甜椒真空冰温保鲜贮藏实验研究

本文将真空贮藏和冰温保鲜这两大第三代保鲜贮藏技术相结合,提出了真空冰温保鲜贮藏的概念。以甜椒为研究对象,对不同贮藏压力、贮藏温度及处理方式下的样品进行真空冰温保鲜贮藏实验研究。测得贮藏过程中的失重率、腐烂指数及商品率,并根据大量的实验数据,进行对比分析,得到真空冰温保鲜贮藏条件下,甜椒的最佳贮藏参数。     

Preservation of strawberries by modified atmosphere packages with other treatments

The impact of modified atmosphere packaging (MAP), in combination with ozone treatment and an edible film coating, on the preservation of strawberries was studied. A combination of 2.5% O₂ with 15% CO₂ was the optimum gas composition for the MAP of strawberries and prolonged shelf‐life by 4–6 days. When the strawberries were pre‐treated with a 4.3 mg/m³ ozone water dip and an edible coating prior to packaging, the shelf‐life was extended to 8–10 days. The results showed that two treatments [No.1: polyvinyl alcohol 134 (2%); monostearatacylglycerol (0.5%); phytic acid (0.05%); sorbitol (0.05%); sodium alginate (0.1%); absolute alcohol (8%): No.2: polyvinyl alcohol 134(1%); soluble starch (1%); glucose (1%); sucrose (1%); sodium alginate (0.1%); sorbitol (0.05%)] gave the best effects on strawberry quality and shelf‐life. All treatments (Nos 1–4) were obviously superior to check experiments for soluble sugar, ascorbic acid, acidity and anthocyanin. Furthermore, the treatments gave superior results for browning index, commodity ratio and permeability of the cell membrane. Copyright © 2006 John Wiley & Sons, Ltd.     

臭氧果蔬保鲜销售包装的实验研究

介绍了臭氧果蔬保鲜技术的作用机理及其特点;在分析果蔬保鲜包装技术要求的基础上,应用臭氧技术结合包装技术方法,在常温下对西红柿、豆角进行了臭氧保鲜实验研究,对腐烂率、减重率、硬度、可溶性固形物含量、还原糖含量、总酸、VC含量、叶绿素含量等指标进行了测试,结果表明:以上果蔬的保鲜期至少延长2周以上,对现代销售中的果蔬保鲜包装具有指导意义.     

黄花菜采后保鲜及活性成分提取方法研究进展

目的 梳理并展望黄花菜采后贮藏保鲜及其活性成分提取的新技术和新方法，以期为黄花菜产业发展提供理论依据。方法 对近年来黄花菜保鲜贮藏方法进行综述，包括冷藏保鲜、生物化学保鲜和辐射保鲜等，并对黄花菜中的多糖、黄酮、多酚等活性成分的提取方法进行总结。结果 选择适宜的保鲜技术可以在一定程度上延长黄花菜的贮藏期，有助于黄花菜产业健康发展；活性成分提取研究报道主要集中在几种黄酮类与多酚类的成分上，提取技术以微波提取法、超声提取法和溶剂萃取法为主。结论 单一保鲜技术的应用对延长蔬菜贮藏期的效果有限，保鲜技术的综合应用才是今后黄花菜保鲜的发展方向，黄花菜活性成分的提取方法以及提取物的功能验证方面研究还不够系统。