LP-7501S用于发酵萝卜中亚硝酸盐降解工艺的研究

为使泡菜中亚硝酸盐快速降解,利用从自然发酵泡菜中筛选出的一株具有高效降解亚硝酸盐功能的优势菌株LP-7501S,对泡菜进行强化发酵,以蔗糖添加量、食盐添加量、氮源添加量、发酵时间和发酵温度进行单因素试验与正交试验,研究其最佳发酵工艺。结果表明最优发酵工艺为:蔗糖添加量0.7%、食盐添加量4%、氮源添加量0.7%、发酵时间84h、发酵温度30℃。在此发酵条件下,测得发酵萝卜中总酸含量为0.73g/100g,亚硝酸盐可快速降解,含量为0.432mg/kg。     

自然发酵泡菜中高体外抗氧化活性乳酸菌的筛选及其对模拟胃肠道环境的耐受性

本研究以自然发酵泡菜为原料,通过氧化氢法初筛,基于自由基清除率和还原能力的复筛,得到高抗氧化活性的菌株,并测定其对胃肠模拟环境的耐受性,利用16S rDNA基因的序列对其进行鉴定。结果表明,初筛得到的75株抗氧化菌株中有14株乳酸菌的DPPH自由基清除能力较强(清除率大于30%),结合羟基自由基清除率、还原活性及亚铁离子还原能力活性的监测,筛选得到2株(Kc 6和Kc 13)具有高抗氧化活性的乳酸菌菌株;2株菌在酸、胆盐、人工胃液和肠液中的存活率均超过了60%,具有较高的模拟胃肠环境耐受性。经鉴定2株菌均为植物乳杆菌(Lactobacillus plantarum)。该菌兼具抗氧化活性和环境耐受性的乳酸菌,能够为可定植体内的功能乳酸菌资源的开发提供新思路。     

Potential role of native pickling cucumber polygalacturonase in softening of fresh pack pickles

This study examined the potential involvement of polygalacturonase (PG) in commercial pickling cucumbers on gradual softening of refrigerated and pasteurized fresh pack pickle products that adversely affects their market-life. PG activity was detected in all sources of commercial pickling cucumbers and refrigerated pickle spears, and activity was detected in some sources of pasteurized spears. Polygalacturonic acid hydrolysis determined from changes in fluidity, reducing groups and oligogalacturonides indicated involvement of both exo- and endo-PG. Treatment of pasteurized pickle mesocarp tissues with concentrated extracts from pickling cucumbers resulted in rapid softening and alteration of pectic substances. D-values for thermal inactivation of pickling cucumber PG at 75, 80, 85, and 90 °C were 22.0, 19.5, 14.5, and 4.2 min, respectively, indicating that residual activity would be expected in commercially pasteurized pickle products. It is concluded that residual cucumber PG could be responsible for softening of processed pickle products, and it is suspected that variations in textural quality of given products are caused by differences in residual types and levels of native PG. PRACTICAL APPLICATION: Since enzyme extracts from commercial pickling cucumbers were demonstrated to be capable of softening pickle tissues and that PG activity was present in some processed fresh pack products, methods that inactivate or eliminate the enzyme(s) should reduce softening of products during storage and marketing.     

Evaluation of internal defect and surface color of whole pickles using hyperspectral imaging

Hyperspectral imaging operated under simultaneous reflectance (400–675 nm) and transmittance (675–1000 nm) modes was studied for non-destructive and non-contact sensing of surface color and bloater damage in whole pickles. Good and defective pickles were collected from a commercial pickle processing plant. Hyperspectral images of these pickles were obtained using a prototype of on-line hyperspectral imaging system, operating in the wavelength range of 400–1000 nm. Principal component analysis was applied to the hyperspectral images of the pickle samples for bloater damage detection. Color of the pickles was modeled using tristimulus values calculated based on the hyperspectral images. There were no differences in chroma and hue angle of good and defective pickles. The average chroma of good and defective pickles was 15.5 and 15.0, respectively, and the hue angle 94.0° and 93.8°, respectively. Transmittance images at 675–1000 nm were much more effective for internal defect detection compared to reflectance images for the visible region of 500–675 nm. An overall defect classification accuracy of 86% was achieved, compared with an accuracy of 70% by the human inspectors. With further improvement, the hyperspectral imaging system could meet the need of bloated pickles detection in a commercial plant setting.     

影响酱腌菜质量的因素及防腐应注意的问题探讨

文中对酱腌菜生产的多种工艺作了介绍,提出了影响酱腌菜质量的一些主要因素,明确了生产过程中应注意的环节,提出了稳定酱腌菜质量的方法,对酱腌菜产品的防腐问题提出了见解.对酱腌菜的生产加工、储存、防腐有一定的指导意义.     

甘肃徽县栗川白塔维修工程报告

徽县粟川白塔建于宋代，在地震中遭到严重破坏。近期．对白塔进行了整体维修，该文即是此次维修情况的技术报告。主要内容包括塔的主要残损情况、加固维修的主要程序及具体技术措施，对其他同类建筑的维修具有一定的参考作用。     

对甜酱什锦菜工艺的探讨

酱菜是我国酿造工业的重要组成部分，甜酱什锦菜是其中的一种。介绍了甜酱什锦菜的制作方法，对其制作过程中的一些注意事项进行讨论。     

泡菜的制作工艺及关键

泡菜是一种既营养又卫生的蔬菜加工品。在我国民间大部分地区均有自制泡菜的习惯，介绍了泡菜制作的工艺流程，重点介绍泡菜制作的三个关键：容器、盐水、调料。     

自然发酵泡菜中乳酸菌的分离及特性研究(二)

本文将继续研究蔗糖浓度对L1-明串珠菌属 (Leuconostoc)和L2 -乳杆菌属 (Lactobacillus)的影响 ,以及他们在泡菜制作中的应用。若在泡菜制作时接种L1、L2 或L1和L2 的混菌 ,均可缩短泡菜的成熟时间 ,但风味不及自然发酵的泡菜