软包装笋热杀菌工艺研究

对软包装笋热杀菌工艺进行了研究。以菌落总数作为评价指标,选择料液比(m笋∶V臭氧水)、臭氧水浓度、处理时间进行单因素试验和正交试验。结果表明,当料液比为1∶8,臭氧水质量分数为4 mg/kg,处理时间为5 min时,减菌化效果最佳;以菌落总数作为评价指标,选择杀菌温度、升温时间、恒温时间进行单因素试验和正交试验。结果表明,当杀菌温度为110℃,升温时间为4 min,恒温时间为15 min时,常压热水喷淋杀菌效果最佳。通过比较该工艺与传统工艺在杀菌后产品的色泽、组织形态和风味,表明采用该工艺灭菌的软包装笋在品质方面均优于传统工艺。     

食用仙人掌红枣复合饮料的研制

以食用仙人掌与红枣为原料,研制出复合饮料生产工艺。通过对仙人掌汁和红枣汁配比的单因素试验和L9（34）正交试验结果表明,食用仙人掌红枣复合饮料的最佳工艺配方为：仙人掌红枣复合汁的配比为5∶5,加糖量为4%,加柠檬酸量为0.03%,复合稳定剂加入量为羧甲基纤维素钠0.2%＋海藻酸钠0.3%,杀菌温度为100℃,杀菌时间为8～15min。     

软包装方便食品红烧极品牛肉的生产工艺研究

为明确中式传统菜肴工业化生产的流程,通过对软包装方便食品红烧极品牛肉产品的原料加工、包装、杀菌、烘干、检测和装箱出货等生产环节的分析和研究,建立了该类菜肴的标准化生产工艺,以期为相关企业提供参考。     

仙人掌饮料研制工艺

以米邦塔食用仙人掌(Opuntia milpa alta)为主要原料,研制出风味独特的仙人掌饮料.仙人掌热烫温度为95℃,热烫时间为2 min,以0.1%碳酸钠、0.01%醋酸锌和0.2%抗坏血酸混合液作为护色剂,护色效果最佳.仙人掌饮料的优选配方为仙人掌汁25%,柠檬酸0.3%,白砂糖4%,蜂蜜4%,CMC-Na0.2%.产品呈淡黄绿色,具备仙人掌特有的清香.     

玉米穗真空包装保鲜技术研究

根据真空包装杀菌原理,针对常规真空保鲜过程中出现的产品酸败、长霉、胀袋、色泽灰暗、褐变等问题,对甜玉米、糯玉米两种类型玉米籽粒授粉后天数即成熟度和玉米果穗直径大小进行分类、分级,研究甜、糯玉米鲜果穗软包装真空保鲜直接杀菌新技术.研究表明,真空包装保鲜甜、糯玉米穗关键技术在于灭菌时间、压力和温度.     

杀菌方式对红烧卤牛肉品质的影响

为保持红烧卤牛肉产品质地和口感等品质的前提下延长其常温保质期,按照公司的标准化配方和工艺加工红烧卤牛肉产品,以沸水杀菌30 min作为对照组（CK）,两次沸水杀菌30 min为处理组EG1,EG2（110 ℃,59 min）、EG3（115 ℃,38 min）、EG4（121 ℃,28 min）处理组分别采用不同温度及不同处理时间进行杀菌,EG5处理组改变煮制和焖制时间后121 ℃杀菌28 min。试验结果表明,CK组的产品感官品质好,脂肪氧化程度低,亮度值高,不易流动水比例高,但产品保温储藏的第4天开袋便有异味和臭味;EG1组的感官品质及质构特性均保持较高水平,但保温储藏第10天时,涨袋率为16.13%,并且涨袋的产品出现明显酸臭味;EG2、EG3、EG4组产品的感官品质及质构特性依次降低,与对照组相比,TBARS值和氯化物含量显著升高（P＜0.05）,不易流动水向自由水方向迁移,但3组均达到商业无菌要求;EG5组在达到商业无菌要求的同时,感官品质、质构特性、TBARS值、色差值都保持较理想状态,不易流动水向左迁移,水分约束力增强。     

黄桃罐头加工工艺技术研究

以黄桃为原料,对其进行预处理,利用护色处理、中温杀菌技术所得的产品色泽、滋味、气味、组织形态明显优于高温杀菌罐头的品质,营养损失少,且达到商业无菌要求。确定护色剂组合为0.9%EDTA-2Na,2%柠檬酸,1%NaHSO_3;过程为升温10 min,达到85℃,恒温杀菌10 min,再经过升温2~3 min,达到再次恒温杀菌温度92℃,杀菌10~12 min,然后快速降温10 min。     

栅栏技术优化即食调味罗非鱼片工艺的研究

为得到风味良好无"土腥味"的罗非鱼即食鱼片,以罗非鱼肉为原料,研究了前处理、烘干方式、杀菌方法、pH值、水分活度和低温处理等多种栅栏因子对即食调味罗非鱼片工艺的影响。结果表明,经质量分数3%的食盐清洗,醋酸调节pH值5.6~5.7,调味后烫煮,产品水分含量45%~50%,水分活度为0.88~0.90,真空包装后低温处理48 h,巴氏杀菌(80~85℃,30 min),可得到美味的休闲即食调味罗非鱼片。     

虎皮鹌鹑蛋的研制

介绍了我国传统风味食品虎皮蛋的产品特点。探索以鹌鹑蛋为主料,研制具有保健作用的五香型虎皮鹌鹑蛋软包装方便食品的工艺条件和产品配方。     

仙人掌保健冰淇淋的研究

研究采用仙人掌原汁、海带、赤藓糖醇生产低热保健冰淇淋的工艺过程,确定最佳用量为仙人掌原汁8%～10%、海带粉0.2%和赤藓糖醇6%。该产品不仅营养价值高,风味独特,而且还具有一定的保健作用,既符合营养要求又健康美味。采用实验法确定仙人掌榨汁的最佳方法,采用感官评定法确定仙人掌的用量。     

仙人掌总黄酮对小鼠抗急性炎症作用的研究

为了探讨仙人掌总黄酮对小鼠的抗急性炎症作用。采用耳肿胀法、毛细血管通透性增加、足肿胀法对仙人掌总黄酮的抗急性炎症作用进行研究。结果表明：仙人掌总黄酮各剂量组小鼠耳肿胀度与空白对照组相比差异极显著(P<0.01);毛细血管通透性增加实验中,各剂量组的OD值与空白对照组相比差异极限著(P<0.01);足肿胀实验中各剂量组0.5~2 h 肿胀度与空白对照组相比差异极限著(P<0.01),但各剂量组3 h足趾肿胀度与空白对照组无显著差异。仙人掌总黄酮对肿胀反应及毛细血管通透性增加有显著的抑制作用,可减轻肿胀和渗出等局部炎症反应,具有一定的抗急性炎症作用。     

不同保鲜膜对平菇保鲜效果的影响

为比较不同保鲜膜对平菇保鲜效果的影响,分别以低密度聚乙烯(LDPE)膜、高密度聚乙烯(HDPE)膜和聚氯乙烯(PVC)膜为包装材料,在模拟超市冷鲜货架温湿度条件[温度约(14±1)℃,贮藏环境相对湿度约85%]下,研究3种不同保鲜膜对平菇的保鲜效果。结果表明：与LDPE膜相比,HDPE 膜和PVC 膜能降低平菇的采后失重率,维持包装内较高的CO₂体积分数和较低的O₂体积分数;在贮藏的前4天,HDPE膜和PVC膜包装的平菇感官分值与LDPE膜包装平菇无显著差异(P>0.05);但贮藏4天后,HDPE 膜和PVC膜包装的平菇其感官分值明显低于LDPE膜,且呼吸强度及细胞膜透性也显著高于LDPE膜(P<0.05)。3种不同保鲜膜以LDPE膜对平菇的保鲜效果最佳。     

天然栅栏保鲜技术对冷鲜羊肉保鲜效果的研究

以新鲜羊肉为原材料,壳聚糖保鲜剂和各种材料的包装袋为2层栅栏,研究了天然栅栏保鲜技术对冷鲜羊肉经真空包装后在4℃贮藏条件下色泽、菌落总数、pH值和TVB-N值等指标变化规律的影响。结果表明,2层栅栏保鲜技术比传统贮藏方式更能有效抑制TVB-N值、菌落总数的上升速度,且以质量分数2%为天然壳聚糖保鲜剂涂膜,结合OPP/PETA/PE包装袋真空包装贮藏效果最佳。     

不同预冷方式、包装及果实规格对番茄预冷效果的影响

研究了不同包装的番茄在常温条件下堆货对其品温、失重率及感官评价的影响,比较了不同预冷方式、包装及果实规格番茄的预冷效果。结果表明：番茄常温堆放24 h后,纸箱包装的番茄品温变化较小,保持果实品质效果较好;番茄压差预冷时间可比冷库预冷时间缩短1 h,且失重率较低;不同规格的番茄预冷速率差异显著,应分别预冷;4种不同的包装中,以塑料箱包装的番茄冷库预冷效果最佳,失重率相对较低。     

HACCP体系在利乐砖纯牛奶生产中的应用

旨在建立一套有效适合于利乐砖纯牛奶生产的HACCP体系,提高产品质量与安全。结合利乐砖纯牛奶生产工艺的各个步骤,分析各个环节可能造成产品质量安全问题的危害和关键控制点。利用HACCP体系各原则,确立了5个有效的CCP及其限值,最后建立了HACCP生产过程各环节执行标准,为安全生产提供技术保障。经验证该体系对于利乐砖纯牛奶产品质量和安全控制有效、可行。     

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.     

常温条件下不同包装方式对杨桃品质及其生理的影响

研究了在常温条件下不同包装对采后杨桃果实品质与生理的影响.结果表明,套袋包装能降低采后杨桃果实水分散失,较好地保持果实的商业品质,延长货架寿命;微孔袋包装能明显地减缓杨桃果实维生素C的氧化降解,抑制果实呼吸速率及乙烯释放量,维持果皮细胞膜的完整性,使果实货架期从8天延长至20天.     

Color and textural quality of packaged wild rocket measured by multispectral imaging

Green color and texture are important attributes for the perception of freshness of wild rocket. Packaging of green leafy vegetables can postpone senescence and yellowing, but a drawback is the risk of anaerobic respiration leading to loss of tissue integrity and development of an olive-brown color. The hypothesis underlying this paper is that color and textural quality of packaged wild rocket leaves can be predicted by multispectral imaging for faster evaluation of visual quality of leafy green vegetables in scientific experiments. Multispectral imaging was correlated to sensory evaluation of packaged wild rocket quality. CIELAB values derived from the multispectral images and from a spectrophotometer changed during storage, but the data were insufficient to describe variation in sensory perceived color and texture. CIELAB values from the multispectral images allowed for a more detailed determination of color compared to measurement with a spectrophotometer with an 8 mm aperture. Furthermore, the multispectral images enabled subtraction of background information of the sample and gave more accurate results on visual color of wild rocket leaves. The combination of wavelengths in the NIR range describing textural changes, and wavelengths in the VIS range describing color changes was optimal for quantification of sensory perceived color and textural quality of packaged wild rocket.     

Distribution center and retail conditions affect the sensory and compositional quality of bulk and packaged slicing cucumbers

During distribution and retail display, fruits and vegetables are often exposed to undesirable temperature and humidity conditions which often result in increased waste due to weight loss and objectionable appearance. Unwaxed fresh-market slicing cucumbers (cv. Calypso) were harvested from a commercial operation and shipped to a distribution center (DC) in Florida. At the DC, 2 d after harvest, cucumbers were sorted and either commercially machine packaged in expanded polystyrene trays covered with a polyvinylchloride film or remained unpackaged for bulk retail display. Cucumbers were transported the next day by truck to a retail store in Gainesville, collected from the store, and stored under optimum (10 °C and 90% RH) or simulated retail display conditions (4 °C or 14 °C and 90–92% RH). Sensory (visual and instrumental color, firmness, shriveling, chilling injury and decay) and compositional quality (pH, titratable acidity, soluble solids and chlorophyll contents) were evaluated initially at the DC and after a 4-d simulated retail display period. Overall, bulk cucumbers were softer, appeared more shriveled, and were more affected by pitting and decay than packaged cucumbers. Bulk cucumbers also appeared lighter green and more yellowish than packaged fruit. Hue angle was less in bulk than in packaged cucumbers, but no consistent differences were observed in the L*, chroma, and hue values between the different temperatures. Small variations in the L*, hue, and chroma values compared to significant losses in chlorophyll content suggest that insufficient chlorophyll degradation occurred to cause major visual color changes. The greater weight loss in bulk cucumbers compared to packaged fruit was associated with accelerated chlorophyll degradation, lower acidity, and lower soluble solids content. Although packaged cucumbers had better visual quality than bulk cucumbers, there was higher RH inside the packages and greater development of decay on packaged fruit. Overall, after the 4-d simulated retail display, the appearance of the cucumbers used in this study was considered to be objectionable due to either yellowing, loss of firmness, shriveling or decay, regardless of the treatment. Results from this study demonstrate the importance of using an appropriate protective package in addition to maintaining the optimum temperature during distribution and retail display. Moreover, initial quality evaluation should be performed upon reception at the DC, and before cucumbers are displayed at the retail store, in order to estimate the remaining shelf life before this product becomes unacceptable for sale.