氮气气调对不同含水量大豆保鲜效果研究

研究了26℃条件下,不同含水量(10%、12%、14%)大豆充氮气调(氮气体积分数96%~98%)与常规贮藏60 d大豆品质指标和霉菌的变化情况。试验表明:充氮气调对抑制大豆发芽率下降,油脂酸值、过氧化值升高有一定效果。当大豆含水量为10%,充氮对发芽率影响显著(P0.05);当大豆含水量为12%,充氮对发芽率、油脂过氧化值影响显著(P0.05);当含水量为14%,充氮对油脂过氧化值影响显著(P0.05),对发芽率、油脂酸值影响极显著(P0.01)。充氮对大豆粗脂肪含量、霉菌菌落总数影响不显著(P0.05)。     

大豆油充氮储藏技术的研究

本实验对大豆油在储藏过程中的性质变化进行研究,在18℃下恒温比较采用充氮技术对油脂品质的影响。在长期储藏的条件下,每个月对大豆油的过氧化值、酸值、碘值进行跟踪测量,以探究充氮技术对大豆油品质的影响。结果表明,空白组的油脂氧化速率相对最快;充氮后随着氮气浓度的增加,油脂的抗氧化能力增强,充入氮气含量80.0%、85.0%、90.0%和95.0%这四组中,氮气含量在95.0%时对油脂氧化的抑制效果最好,12个月后过氧化值为5.56mg/kg,酸值为0.14mgKOH/g,碘值为108.6g/100g。     

充氮气调储藏对棕榈油品质的影响

对棕榈油在常规储藏和充氮气调储藏条件下的酸值、过氧化值变化规律进行研究。结果显示:棕榈油在储藏过程中酸值增势缓慢,过氧化值增加显著;和对照组相比,充氮气调储藏对酸值的变化趋势基本无影响,但能使过氧化值的增幅明显减缓。     

大豆原油充氮储存品质变化规律的研究

通过对充氮储存和常规储存条件下大豆原油品质指标的检测分析,研究充氮储存条件下大豆原油品质的变化。结果表明:与常规储存的大豆原油相比,在北京地区充氮储存22个月的条件下,大豆原油的气味、滋味、色泽、透明度、羰基值无显著改变,加热试验后色泽变浅,溶剂残留量总体下降;充氮储存的大豆原油酸值、过氧化值较常规储存的上升缓慢。充氮储存对延缓油脂劣变有明显效果,可以延缓油脂氧化速度,对保证油脂储存品质有良好作用。     

线性回归和动力学方程在大豆原油储存品质预测上的应用

通过对北京市常规储存和充氮储存条件下大豆原油过氧化值和酸值的跟踪检测,使用线性回归和动力学方程对不同储存条件下大豆原油储存3年时的品质做出了预测。结果表明,常规储存的大豆原油储存3年时的过氧化值约是入库时的2.3倍,酸值约是入库时的1.1倍;充氮储存的大豆原油储存3年时的过氧化值约是入库时的1.3倍,酸值约是入库时的1.1倍。由此确定了北京市油脂储存入库品质的要求为过氧化值不大于2.0 mmol/kg,酸值不大于2.0 mgKOH/g,为油脂出库品质指标的估算提供了新的思路,为北京市地方储备油储存轮换提供了数据支持。     

储藏方式对东北地区大豆储藏品质的影响

通过对东北地区3个仓库储藏的大豆在储藏期间的储藏温度、水分、发芽率、氮可溶性指数、糊化品质、脂肪酸值和霉菌量进行检测,探究不同储藏方式对大豆储藏期间品质的影响。结果显示:相较于机械通风方式,内环流控温储藏能够同比降低储藏温度15.12%,延缓水分含量降低速率和大豆的总酸度增加,并降低蛋白质的变性程度。内环流控温储藏能够延缓储藏期间内大豆的发芽率下降速率,提高加工品质,延迟大豆脂肪酸值的提高,降低大豆霉菌增长速率,有助于东北地区大豆储藏品质的提升。     

茶多酚对精炼菜籽油的抗氧化作用

以“绿宝牌”茶多酚为主要成分，配制纯天然油脂抗氧化剂，应用于高级精炼菜籽油中，并同复合合成抗氧剂、α─生育酚和充氮气比较，用国标法测定油脂的过氧化值和酸值，结果证明使用量相同的条件下（０．０３％），茶多酚抗氧化剂远优于复合合成抗氧剂，能延长精炼菜籽油的保质期（ＰＯＶ≤１０ｍｅｑ／ｋｇ）三倍以上，而充氮和使用α─生育酚无明显效果。     

真菌固态发酵预处理大豆高效提油的初步研究

利用黄曲霉和黑曲霉固态发酵大豆,通过测定还原糖和氨态氮含量的变化．判断真菌对营养成分的利用情况与油脂提取效果的关系。结果表明：在3h的提油时间里．大豆经黑曲霉和黄曲霉固态发酵预处理后,分别在发酵96h和72h达到最大提油量,为23％（w／w）和21．6％（w／w）,比对照组（15．6％,w／w）分别提高47．4%和38．5％,提油量都有很明显的提高。对发酵前后油脂的酸值和过氧化值测定结果表明：发酵后油脂的酸值和过氧化值均高于未发酵的油脂．     

地下储油与地上储油对油脂品质的影响北大核心CSCD

油脂在储存过程中,其品质指标易受温度等因素的影响。将大豆原油和菜籽原油储存于室外地上和埋于室外地下的钢制储罐,定期取样测定油脂的水分及挥发物、酸值、过氧化值、色泽、挥发性成分、脂肪酸组成、反式脂肪酸含量、氧化稳定性及甾醇和维生素E含量,考察不同储油方式对大豆原油和菜籽原油品质的影响。结果表明:地下储油温度变化较小,基本在11~27℃之间,地上储油温度变化较大,最高接近45℃,最低接近0℃;地上、地下储油中均未检出反式脂肪酸,储油方式对油脂水分及挥发物、色泽、脂肪酸组成影响较小;储存12个月时,地上、地下储存大豆原油酸值升幅分别为83.3%、12.5%,地上、地下储存菜籽原油酸值升幅分别为86.4%、19.0%,地上、地下储存大豆原油过氧化值升幅分别为243%、218%,地上、地下储存菜籽原油过氧化值升幅分别为219%、167%;地下储油的氧化稳定性优于地上储油,地下储油对部分重要挥发性成分和甾醇、维生素E等油脂营养成分的的保留效果优于地上储油。总的来说,地下储油是良好的油脂品质保鲜技术,不但能控制氧化速率,对营养价值及风味的保持效果也较好。     

微波干燥对芝麻品质特性的影响

研究微波干燥温度和干燥时间对芝麻的水分含量、发芽率及其油脂的酸价和过氧化值的影响,并利用固相微萃取-气质联用仪对处理后芝麻的挥发性成分进行了研究。结果表明:在低于90℃温度下干燥的前20 min内,芝麻含水量下降迅速,超过20 min后随着时间的延长,芝麻的水分散失速度逐渐变慢;微波干燥对芝麻的发芽率有破坏作用。干燥的前20 min内,温度低于80℃时,干燥温度升高对芝麻油酸值和过氧化值的影响不显著(p0.05),而温度高于80℃时,其对芝麻油酸值和过氧化值有显著影响(p0.05);随着干燥温度升高,干燥芝麻的主要挥发性成分烷烃类、萘类、酚类成分含量降低,醛类含量升高。     

酶法水解麦胚制取持水剂的研究

采用响应面分析方法研究了酶法水解麦胚制取持水剂的生产工艺，并对产品应用于香肠中的抗氧化效果进行了试验。试验结果表明：酶法水解麦胚制取持水剂的优化工艺参数为：对１０％的麦胚乳４００ｍｌ，反应温度为４４．４℃，反应时间为４ｈ，酶与底物浓度比为８６０μ／ｇ。经优化工艺生产的持水剂的水分活度为０．８９６，所对应的水解度为２６．５％。应用于香肠可显著提高其货架寿命。     

Relationship of Physicochemical Characteristics with Sensory Profile of Cookies Enriched with Medicinal Herbs

In this work, a range of model cookies enriched with different quantities of medicinal herbs, applied in two forms (pulverized mixture and extract), were studied to compare and describe relationships between physicochemical and sensory data. Multivariate statistical methods were applied to estimate relationships in the analyzed data. Analysis of variance showed that the majority of analyzed parameters were highly significant in discriminating among the samples (p < 0.05), which supported the usefulness of their application in characterizing the quality profile of enriched cookies. Principal component analysis on physicochemical data revealed that cookies at the same enrichment level showed more similarities. Principal component analysis on sensory data exhibited a larger separation between the samples with increasing enrichment levels, especially in the case of pulverized herbal mixture. According to partial least squares regression, two significant partial least squares components explained 92.7% and predicted 78.0% variation in the data. The most important parameters in discriminating between the cookies enriched with medicinal herbs were lightness, red tonality, and hardness. The selected physicochemical parameters could be used in future studies to evaluate variously enriched cookies by establishing models and investigating the predictability of sensory quality.     

酸解-酶膜联用法检测谷氨酰胺

研究了谷氨酰胺在酸性条件下的水解特性后 ,建立了酸解 酶膜联用的谷氨酰胺定量分析方法。此方法的线性范围为 10～ 40mmol/L ,相关系数R =0 .999,分析误差为 0 .1mmol/L ,测量所需时间约为 30min。     

Effect of treatment with non-alcoholic beverages of patients with gastritis and hyposecretion

A positive effect of use of non-alcoholic drink "Shirinskaia high-vitaminized treatment-board Water" in complex treatment of chronic gastritis with hyposecretion was revealed.     

强度为Weibul分布,应力为其他分布的可靠度求解

运用应力—强度相干理论,推导出强度为Ｗｅｉｂｕｌ分布,应力为其他分布时可靠度求解表达式,并应用专用数学软件Ｍａｔｈｅｍａｔｉｃａ实现了数值的求解。文中给出若干求解实例,求解的过程简便、直观,有利于工程可靠性设计与分析借鉴     

猪皮制革必须适应市场经济

本文讨论了猪皮制革的现状,分析其成因,在此基础上阐明了猪皮制革必须适应市场经济的观点,并提出了猪皮制革走出低谷的若干具体对策。     

Genetic evaluation of dairy cattle with test-day models with autoregressive covariance structures and with a 305-d model

This study compared genetic evaluations from 3 test-day (TD) models with different assumptions about the environmental covariance structure for TD records and genetic evaluations from 305-d lactation records for dairy cows. Estimates of genetic values of 12,071 first-lactation Holstein cows were obtained with the 3 TD models using 106,472 TD records. The compound symmetry (CS) model was a simple test-day repeatability animal model with compound symmetry covariance structure for TD environmental effects. The AR_s and AR_e models also used TD records but with a first-order autoregressive covariance structure among short-term environmental effects or residuals, respectively. Estimates of genetic values with the TD models were also compared with those from a model using 305-d lactation records. Animals were genetically evaluated for milk, fat, and protein yields, and somatic cell score (SCS). The largest average estimates of accuracy of predicted breeding values were obtained with the AR_s model and the smallest were with the 305-d model. The 305-d model resulted in smaller estimates of correlations between average predicted breeding values of the parents and lactation records of their daughters for milk and protein yields and SCS than did the CS and AR_e models. Predicted breeding values with the 3 TD models were highly correlated (0.98 to 1.00). Predicted breeding values with 305-d lactation records were moderately correlated with those with TD models (0.71 to 0.87 for sires and 0.80 to 0.87 for cows). More genetic improvement can be achieved by using TD models to select for animals for higher milk, fat, and protein yields, and lower SCS than by using models with 305-d lactation records.     

遮盖山羊绒“亮丝”的媒介/活性染色工艺

针对变异山羊绒的"亮丝"现象,以及不同染料在羊绒纤维不同位置上染的差异性,采用酸性媒介染料和毛用活性染料复配染色。结果表明,与单一染料染色工艺相比,复配染色技术通过对关键染料和助剂的精准控制,优化染色工艺,覆盖"亮丝"的效果良好。染色产品和染色废液中的铬含量均符合相关标准。     

Decontamination of broilers with hydrogen peroxide stabilised with glycerol during processing

Experiments were conducted to assess the effects of different concentrations of hydrogen peroxide stabilised by glycerol solution in potable water on the bacteriological and organoleptic quality of freshly slaughtered broiler carcasses. Skin-pH and colour were measured 3.5 and 24 h after treatment and compared to untreated carcasses. Bacterial colonisation was determined 3.5 and 24 h and, 7 days after treatment, carcasses being stored at 1 degrees C. None of the concentrations used affected the appearance and "bloom" of the carcasses as could be measured by colorimeter and changing of the acidity. Mean microbial counts were significantly reduced (P<0.01) when treated and control broilers were compared. Average reductions of 0.3 up to1.4 log N for the mesophilic aerobic counts were achieved and from 0.4 up to 1.2 log N for Enterobacteriaceae. A 3% w/w solution made from a commercially available stock solution (Glyroxyl), which consists of 44% hydrogen peroxide, 44% demineralised water and 12% glycerol proved to lower colonisation more effectively than a 2% solution.     

芦荟蒽醌和多元羧酸对棉织物的复合整理

针对棉织物抗紫外线及抗皱性较差的缺点,用芦荟蒽醌化合物和柠檬酸、酒石酸对棉织物进行后整理,通过多元羧酸的桥联作用,使蒽醌提取物与棉纤维大分子发生较为牢固的化学结合,使棉织物同时获得耐久的抗皱抗紫外性能。通过扫描电子显微镜、红外光谱图、x射线衍射测试,证实多元羧酸与棉纤维大分子按环酐机制发生了酯化反应,芦荟蒽醌通过多元羧酸的桥联作用以化学键的形式固定在棉纤维上。对整理后织物的紫外线透过率、断裂强力、白度、折皱回复角等性能进行测试,结果表明,棉织物的抗皱性能和抗紫外性能明显提高。