DNA and chemical analyses of commercial fly agaric-related products

Since June 6, 2002, psilocin and psilocybin-containing fungi (commonly called "magic mushrooms") have been regulated by the Narcotics and Psychotropics Control Law in Japan. However, various fly agaric-related products are now entering the Japanese market via the internet. In this study, fly agaric-related products available in this way were investigated for raw materials by DNA analysis and for additives by chemical analysis. Nucleotide sequence analysis of the mitochondrial 12S rDNA region suggested that these fly agaric-related products originate from A. muscaria or A. muscaria var. persicina. Furthermore, they were classified into three strains based on the ITS2-LSU nucleotide sequence. Harmine derivatives and/or tryptamine derivatives were detected in some of these products by LC/MS analysis. In accordance with this, the matK gene of Peganum harmala was found in all of the harmine derivative-containing samples.     

Effect of storage on resistant starch and amylose content of cereal–pulse based ready-to-eat commercial products

A wide range of ready-to-eat (RTE) foods, with varied shelf life are commercially available to meet the increasing demand for convenience foods, both by the Armed Forces and the public at large. The study evaluated the effect of storage on the resistant starch (RS) and amylose content of selected ready-to-eat (RTE) cereal–pulse based processed foods viz., pongal, khara bhath, dal fry, bisibele bhath, rajmah and kesari bhath, developed by Defence Food Research Laboratory, Mysore. RS was quantified directly in the residues obtained after removing digested starch in simulated physiological conditions. Nutrient composition and carbohydrate profile of the foods were also analyzed. The carbohydrate profile indicated low amounts of sugars, except in case of kesari bhath. The total starch content ranged from 14.5 to 24 g% while amylose ranged from 1.2 to 7.2 g%, respectively. The total and resistant starch in the RTE foods varied depending on the ingredients used and type of processing. Foods containing higher amylose content were found to have maximum increases in RS content after storage. Storage at ambient conditions resulted in significant increases (p < 0.05) in RS and TS content of RTE foods. The findings reveal that the RTE foods studied hitherto contained appreciable quantities of RS, which further increased on storage.     

谷氨酰胺转胺酶在谷物制品中的应用

介绍了微生物谷氨酰胺转胺酶的理化性质和作用机理.详细描述了谷氨酰胺转胺酶在谷物制品中的应用,重点叙述了其在面制品中的用途,并展望了其在食品中的广阔的应用前景.     

Fractional extraction of cereal flour proteins

Wheat (Wichita), rye, barley, oat and maize flours were successively extracted with 0.04 m sodium chloride solution (3 × ), water (3 × ), 70% ethanol (3 ×) and 0.1 N acetic acid. The fractions and residues were analysed for nitrogen and subjected to starch-gel electrophoresis. Saline extractions chiefly removed the albumins and globulins of all five cereals. The prolamins of wheat, rye and barley appeared mostly in the three aqueous extracts but also, particularly, those of very low mobility, occurred in the alcoholic solutions. The acetic acid-soluble fractions of wheat, rye and barley were shown by electrophoresis under reducing conditions to be crosslinked by S.S bonds; those of rye and barley showed some characteristic differences from glutenin. Oats and maize were practically devoid of this fraction. Most of the protein of oats and maize was insoluble. Electrophoresis patterns after reduction were obtained from insoluble fractions, though there were differences among the genera. Both overall protein solubility and the quantity of the acetic acid-soluble fraction were correlated with baking quality. The presence of covalent crosslinks other than S.S in glutelin fractions is suspected.     

一种适用于乳制品基因组DNA快速提取方法的研究

目的对比NaOH裂解法、PBS裂解法以及直接煮沸法3种方法提取乳制品中核酸的提取效果,优化提取条件,确定一种更适用于现场检测、简便快速的的乳制品DNA快速提取技术。方法以牛奶、水牛奶、牦牛奶、羊奶、骆驼奶、以及驴奶6种常见的乳制品为材料,分别用NaOH裂解法、PBS裂解法以及直接煮沸法3种提取方法提取乳制品中的DNA,并根据裂解液用量和裂解时间进行优化,通过PCR扩增和琼脂糖凝胶电泳分析,检测DNA提取的质量和灵敏度。结果 NaOH裂解法能够提取所有物种的乳制品DNA,而且可以在最佳裂解条件下提取模拟掺假混合乳的DNA进行检测,发现其检测限能达到1%的牛奶含量。结论该方法取样量小,成本低,在15 min内即可完成快速提取,为实验室乳制品DNA定性或定量鉴别,以及乳制品的现场掺假鉴别提供了一种快速灵敏低成本的样品前处理技术。     

Comparison of six commercial DNA extraction kits for detection of Brucella neotomae in Mexican and Central American-style cheese and other milk products

Raw or inadequately pasteurized milk from infected animals and cheese made with such milk are a frequent vehicle for human brucellosis infection. Also, biological terrorism is a concern with certain Brucella spp. Due to matrix-associated real-time polymerase chain reaction (qPCR) inhibitors, robust sample preparations are crucial. We compared six commercial nucleic acid extraction kits using nine Mexican and Central American-style soft cheeses or creams and three liquid milk products inoculated with Brucella neotomae, a surrogate for pathogenic Brucella spp. Kits were evaluated by purity and quantity of DNA as determined by qPCR Ct values, reproducibility across cheese and milk types, and cost. At 10⁷ CFU/g in four different cheeses, Qiagen statistically outperformed all other kits. When two cheese styles were inoculated at dual levels, Qiagen and High Pure kit extracted samples at 1.5 × 10⁵ CFU/g produced average Ct values of 34–39, while PrepSEQ and MagMAX kit extracted samples exhibited higher or no Ct values. High Pure and Qiagen kits excelled also with liquid milk products. Considering matrices, inoculation levels, and kits evaluated, High Pure and Qiagen products produced Brucella DNA of high quality and quantity indicated by the lowest Ct values and were the least expensive.     

In-vitro availability of starch in cereal products

The in-vitro availability of starch in Heudebert breads and Lu biscuits was assessed. Starch digestibility increased in the order semi-sweet biscuits, muesli, wholemeal breads, white breads, French toast, extruded crispbread. The results confirm that manufacturing conditions play a determinant role in starch availability in vitro.     

感官评价及其在谷物制品中的应用现状

简要介绍了感官评价的定义、应用及其在食品工业中的重要性。重点阐述了感官评价在部分谷物制品评价中的应用,包括大米食味和小麦粉制品食用品质的感官评价。详细描述了大米、面条、面包、馒头品质的感官评价方法、相关研究及存在的问题等。     

Mycotoxins in cereal grain Part VII. A simple method to assay mycotoxin potential of cereal grain and cereal products

A simple test to assay mycotoxin potential of cereal grain and products was elaborated. In cereal grain samples during 1977 and 1981 formation of ochratoxin A, citrinin and zearalenone was observed respectively in 40%, 7 % and 31 % of cereals samples. Aflatoxin and sterigmatocystin were not formed in any sample of cereal grain. Citrinin and penicillic acid were found as mycotoxins accompanying ochratoxin A.     

A review on ochratoxin A occurrence and effects of processing of cereal and cereal derived food products

Ochratoxin A (OTA) continues to grab global attention and concern for the hazard and impact that embody for both human and animals, based on its toxicity and occurrence. Despite OTA has been described in a myriad of foodstuffs, cereal and its derivatives remain the major contributors to OTA exposure. For that reason, a critical review on OTA occurrence reported by recent studies worldwide focusing on unprocessed and processed cereal foodstuffs is made in this work. Special attention is drawn to the major cereal derived products, namely flour, bread, breakfast cereals, baby/infant foods and the inherently involved technological food processing methods and its influence on the redistribution and chemical modification of OTA.     

Mycotoxins in cereal grain. Part VII. A simple method to assay mycotoxin potential of cereal grain and cereal products

A simple test to assay mycotoxin potential of cereal grain and products was elaborated. In cereal grain samples during 1977 and 1981 formation of ochratoxin A, citrinin and zearalenone was observed respectively in 40%, 7% and 31% of cereals samples. Aflatoxin and sterigmatocystin were not formed in any sample of cereal grain. Citrinin and penicillic acid were found as mycotoxins accompanying ochratoxin A.     

Analysis of free amino acids in cereal products

Free amino acids were extracted from cereal products using 50% ethanol to prevent solubilization of polysaccharides and other viscous polymers and to avoid starch gelatinization. The extracts were analyzed by GC after ion-exchange solid phase extraction and chloroformate derivatization using Ez-Faast technology (Phenomenex). Free amino acids in cereal products could be analyzed within 1 h of extraction and determination, with good separation between peaks and repeatable retention times. Relative correction factor for each amino acid was established. The matrix did not affect the results and the method was repeatable for most of the amino acids (coefficient of variation was in the order of 10%). Different fractions and products of wheat, rye, oats and barely were analyzed. The bran contained more free amino acids than did the other analysed fractions of cereals. Fermentation seemed to consume free asparagine and aspartic acid and to use or release other amino acids.     

真空包装在谷、豆类食品中的应用

<正> 大型购物中心和超级市场的迅速崛起,使传统的食品包装形式出现了许多问题,不得不从根本上进行改变。一般来说,大型分销中心要求的产品体积较大,而且同类的产品会被并排放置于货架上,从而带来激     

Phytic acid content in milled cereal products and breads

Phytic acid was determined in cereal (brans, flours and milled wheat-products) and breads. The method was based on complexometric titration of residual iron (III) after phytic acid precipitation. The cereal flours showed values ranged between 3–4 mg/g for soft wheats, 9 mg/g for hard wheat and 22 mg/g for whole wheat. Corn, millet and sorghum flours reported a mean of 10 mg/g and oat, rice, rye and barley between 4 and 7 mg/g. Wheat brans had wide ranges (25–58 mg/g). The phytic acid for oat brans was half that of wheat bran (20 mg/g) and higher value (58 mg/g) than that for rice bran. The milling products (semolinas) from hard wheat exhibited 10 mg/g and soft wheat a mean of 23 mg/g. The breads made with single or mixture cereal flours exhibited ranges between 1.5 and 7.5 mg/g. The loss of phytic acid relative to unprocessed flours was between 20% for oat bread and 50% for white bread.     

冲调谷物制品污染菌相的调查分析

目的 了解冲调谷物制品中的微生物污染情况及主要污染菌种类,探讨传统形态学鉴定法、分子生物学鉴定法和基质辅助激光解吸电离飞行时间质谱法（matrix assisted laser desorption ionization time of flight mass spectrometry, MALDI-TOF-MS）鉴定微生物的适用效果。方法 以流通领域抽取的冲调谷物制品为研究对象,采用国家标准方法对其菌落总数和霉菌进行计数,分离纯化不合格产品中的污染菌,以基质辅助激光解吸电离飞行时间质谱（matrix assisted laser desorption ionization time of flight mass spectrometry, MALDI-TOF-MS）结合16S rRNA序列分析方法对污染细菌进行鉴定,以MALDI-TOF-MS方法结合传统形态学鉴定方法对污染霉菌进行鉴定。结果 110批次冲调谷物制品的菌落总数不合格率为3.6%,霉菌计数不合格率为4.5%;分离得到的159株细菌可归于28个种,芽孢杆菌属（Bacillus）细菌为优势菌群,分离频率达到71.7%;分离得到的98株霉菌可划分至25个属,青霉属（Penicillium）和曲霉属（Aspergillus）为优势菌群,分离频率分别为12.4%和7.1%。污染菌中含有克罗诺杆菌（Cronobacter）等条件致病细菌和多种常见产毒真菌,存在一定的食品安全风险。结论 冲调谷物制品的微生物污染情况较为严重,生产企业应重视生产加工过程中的微生物污染问题,相关部门应加强对冲调谷物制品的食品安全监管。MALDI-TOF-MS方法在鉴定细菌时具有较大优势;受限于真菌数据库的不足,其用于食品来源霉菌鉴定的准确率有待提高。     

青稞紫米复合谷物饮料的研发

以高原特色农作物--青稞为主要原料,与黄豆、紫米和黑芝麻榨出液进行复配,研究开发出青稞紫米复合谷物饮料。通过正交试验,筛选出最优配比为：豆浆50ml、青稞液115ml、紫米黑芝麻液70ml、蔗糖3.5%。该饮料是一种谷香醇厚,具有较高营养价值的谷物复合蛋白饮料。     

大米及其制品中的RS3

测定了英国市场上销售的Basmati(白米,糙米)(长粒米),泰国香米(长粒米),日本大米(短粒米)样品中RS3的含量,比较长粒米和短粒米在熟化过程的稳定性以及不同米制品中含量的差异.结果表明,短粒大米RS3含量高于长粒大米;熟化过程对RS3含量的影响巨大,其中白米米粉在熟化过程中RS3含量下降的程度低于糙米米粉,长粒米米粉、短粒米米粉在熟化过程中RS3含量下降的程度差异不大;保鲜米饭与同品种大米制作熟化大米粉的RS3含量基本相当.