Influence of Heating during Cooking on Trans Fatty Acid Content of Edible Oils: A Systematic Review and Meta-Analysis

Consumption of trans fatty acids (TFA) is associated with adverse health outcomes and is a considerable burden on morbidity and mortality globally. TFA may be generated by common cooking practices and hence contribute to daily dietary intake. We performed a systematic review and meta-analysis to investigate the relationship between heating edible oils and change in their TFA content. A systematic search of experimental studies investigating the effect of various methods of heating on TFA content of edible oils was conducted in Medline and Embase since their inception up to 1 October 2020 without language restrictions. Comparable data were analysed using mixed multilevel linear models taking into account individual study variation. Thirty-three studies encompassing twenty-one different oils were included in this review. Overall, heating to temperatures <200 °C had no appreciable impact on different TFA levels. Between 200 and 240 °C, levels of C18:2 t (0.05% increase per 10 °C rise in temperature, 95% CI: 0.02 to 0.05%), C18:3t (0.18%, 95% CI: 0.14 to 0.21%), and total TFA (0.38%, 95% CI: 0.20 to 0.55%) increased with temperature. A further increase in total TFA was observed with prolonged heating between 200 and 240 °C. Our findings suggest that heating edible oils to common cooking temperatures (≤200 °C) has minimal effect on TFA generation whereas heating to higher temperatures can increase TFA level. This provides further evidence in favour of public health advice that heating oils to very high temperatures and prolonged heating of oils should be avoided.     

Pasting Characteristics,Baking and Sensory Qualities of Cakes from Blends of Cassava and Wheat Flours

Wheat flour was replaced with cassava flour (30 to 100%) to produce cake. Composition and pasting properties of the flours and their composite flour blends were determined. Baking and sensory qualities of the resulting cake samples were evaluated. Protein starch and fiber contents of the cassava and wheat flours were 1.5; 71.50; 1.94% and 10.9; 69.89; 2.81% respectively, which significantly influenced their pasting and baking characteristics and also reflected in their composite blends. Peak, holding, breakdown and final viscosities of the blends ranges from 90.1 to 121.1; 51.6 to 82.7; 38.21 to 42.62; and 93.4 to 125.8 Rapid Visco Unit (RVU) respectively. Specific volume decreased from 1.49 to 1.18 ml/g. Cake of comparable qualities with that obtained from wheat were obtained within 40% substitution level.     

温度对决明子化学成分和药理作用的影响

考察了温度对决明子化学成分和药理作用的影响。大黄酚含量随受热温度升高而升高；保肝类成分含量则下降。药理试验表明，样品受热温度升高，其对抗四氯化碳急性肝损伤作用和通便作用减弱。     

双波长法测定马钱子中马钱子碱和士的宁含量及马钱子炮制原理探讨

报道了以双波长分光光度法同时测定马钱子中马钱子碱、士的宁含量。本法可消除马钱子碱和士的宁相互间的干扰,可用作生药及其炮制品质量控制手段,分析了法定方法中存在的问题。考察了马钱子碱和士的宁对热稳定性,探讨了马钱子炮制减毒的机理。     

金银花采收及产地初加工研究

目的对金银花采收和产地加工中关键工艺进行了研究。方法以绿原酸和木犀草苷含量为指标,利用高效液相色谱法对金银花进行含量测定。结果不同采收期及加工方法所得含量差异显著;微波杀青烘干法所得金银花品质最佳。结论河南产区金银花最佳采收时间为5月份,适宜在二白至大白期采收;微波杀青烘干法是一种提高金银花品质的新型干燥方法。     

地榆烘法制炭前后止血作用比较

目的 比较地榆烘法制炭前后的止血作用。方法 昆明小鼠60只,随机分为6组：对照组,云南白药（阳性药,0.667 g/kg）组,地榆高、低剂量（8、2 g生药/kg）组,地榆炭高、低剂量（8、2 g生药/kg）组,每天ig给药1次,连续给药3 d,于末次给药1 h后检测小鼠出血时间、凝血时间,血凝仪检测凝血酶原时间（PT）、凝血酶时间（TT）、活化部分凝血活酶时间（APTT）,进行血小板计数。结果 与对照组比较,高剂量地榆和烘制的高、低剂量地榆炭显著缩短小鼠的出血时间、凝血时间、PT、TT和APTT;高、低剂量地榆和高剂量地榆炭显著提高血小板计数;与地榆高剂量组比较,高剂量地榆炭能显著缩短小鼠的PT、TT、出血和凝血时间,对血小板数量和APTT的影响差异不显著。结论 地榆烘法制炭后止血作用增强。     

小苏打联合红霉素治疗对新生儿功能性呕吐的疗效

目的：探讨小苏打联合小剂量红霉素对新生儿功能性呕吐的临床疗效。方法收集嵊州市妇幼保健院2009年1月至2011年12月150例功能性呕吐患儿资料，按采取的治疗方法不同分为观察组、对照1组和对照2组各50例，观察组采用小苏打联合小剂量红霉素治疗，对照1组采用小剂量红霉素治疗，对照2组单纯采用对症治疗，观察3组患者的治疗效果。结果观察组总有效率为96％，高于对照1组的80％和对照2组的60％（χ2＝23．44，17．06，P＜0．05）；观察组的症状缓解时间、奶水摄入量、体重增加情况优于对照组（t1值分别为8．43、10．45、5．32，t2值分别为9．50、11．22、6．03，均P＜0．05）；且观察组的各血液生化指标也优于对照组（ t1值分别为6．20、6．05、6．34、6．20，t2值分别为7．11、7．29、7．03、7．47，均P＜0．05）。结论小苏打联合小剂量红霉素治疗新生儿功能性呕吐疗效肯定，值得临床推广应用。     

双波长法测定马钱子中马钱子碱和士的宁含量及马钱子炮制原理探讨

报道了以双波长分光光度法同时测定马钱子中马钱子碱、士的宁含量。本法可消除马钱子碱和士的宁相互间的干扰,可用作生药及其炮制品质量控制手段,分析了法定方法中存在的问题。考察了马钱子碱和士的宁对热稳定性,探讨了马钱子炮制减毒的机理。     

The Effect of Baking Heat Treatment on the Fatigue Strength and Life of Shot Peened 4340M Landing Gear Steel

In this study, the effect of baking heat treatment on fatigue strength and fatigue life was evaluated by performing baking heat treatment after shot peening treatment on 4340M steel for landing gear. An ultrasonic fatigue test was performed to obtain the S–N curve, and the fatigue strength and fatigue life were compared. The micro hardness of shot peening showed a maximum at a hardened depth of about 50 μm and was almost uniform when it arrived at the hardened depth of about 400 μm. The overall average tensile strength after the baking heat treatment was lowered by about 80–111 MPa, but the yield strength was improved by about 206–262 MPa. The five cases of specimens showed similar fatigue strength and fatigue life in high cycle fatigue (HCF) regime. However, the fatigue limit of the baking heat treated specimens showed an increasing tendency rather than that of shot peening specimens when the fatigue life was extended to the very high cycle fatigue (VHCF) regime. The effect of baking heat treatment was identified from improved fatigue limit when baking heat was used to treat the specimen treated by shot peening containing inclusions. The optimum temperature range for the better baking heat treatment effect could be constrained not to exceed maximum 246 °C.