DETECTION AND IDENTIFICATION OF LACTOBACILLUS LINDNERI FROM BREWERY ENVIRONMENTS

Ten detection media and six cultivation techniques were evaluated for the detection of a harmful brewery contaminant, for which the name Lactobacillus lindneri was recently revived. These bacteria showed slow and weak growth on solid media. However, enrichment of beer with NBB-C or the use of a mixture of MRS and beer (4:1 v/v) reduced the detection time by 2 days or more, depending on the strain, compared to cultivation on solid brewery media. Eight brewery isolates from different origins, the type strain and a test strain were characterized by carbohydrate fermentation tests (API 50 CHL), by a chemotaxonomical (SDS-PAGE) and by a genomic fingerprinting (ribotyping) method. The results obtained by all these methods indicated that the isolates studied form a single group and can be assigned to the species L. lindneri. However, using the current standard reagents, ribotyping cannot discriminate the strains isolated from different sources .     

IDENTIFICATION OF A GROWTH FACTOR IN TOMATO JUICE FOR A NEWLY ISOLATED STRAIN OF PEDIOCOCCUS CEREVISIAE

A newly isolated strain (L-73) of Pediococcus cerevisiae showed very slow growth in the Nakagawa medium which has been routinely used for the detection of lactic acid bacteria in the brewery. When the Nakagawa medium was enriched with 2% tomato juice extract or when the medium was prepared with the use of unhopped beer, strain L-73 showed good growth. The growth-stimulating factor in tomato juice was purified by chromatography on a charcoal column and it was finally identified by bio-autography as 4′-0-(β-D-glucopyranosyl)-D-pantothenic acid.     

乳酸片球菌细菌素的活性及特性的研究

试验采用TGE（trypticase glucose yeast extlact）肉汤培养基作为乳酸片球菌的培养基，培养条件为37℃过夜静止培养。利用改变pH的方法，即通过菌体对细菌素的吸附与解吸，对细菌素进行分离纯化，试验表明细菌素对植物乳杆菌，绿脓杆菌，单核细胞增多症李氏杆菌，沙门氏菌，枯草杆菌，金黄色葡萄球菌和大肠杆菌O157均有抑制作用。并且还具有耐热，耐盐的特性．     

APPLICATION OF SEROLOGICAL METHODS TO THE EXAMINATION OF YEAST VARIATION AND BEHAVIOUR

The technique of micro immuno-electrophoresis has been used to study variation within single yeast strains. Investigation of brewing yeasts and their variants demonstrated that a change of a fermentation property was accompanied by a change in the antigenic structure. Small variations in fermentation characteristics, as well as a larger changes such as respiratory deficiency, can be detected by this serological method.     

A SIMPLE,RAPID METHOD FOR THE DETECTION OF SUBSPECIES OF ZYMOMONAS MOBILIS

Zymomonas strains are simply and rapidly detected after growth in a selective liquid medium by the addition of a Schiff's reagent. This dye reacts with acetaldehyde produced by Zymomonas to give a deep purple colour. The optimal conditions for the test are evaluated and it is shown to be specific for Zymomonas strains. The use of the dye reaction in routine microbiological quality control is described. A comparison is presented of the dye test and the use of an agar medium containing sulphite and lead acetate on which Zymomonas strains which produce H₂S form characteristic colonies.     

RECENT ADVANCES IN THE RAPID DETECTION OF BREWERY MICRO-ORGANISMS AND DEVELOPMENT OF A MICROCOLONY METHOD

Recent developments in the rapid detection of low concentrations of micro-organisms are reviewed. A modification of the microcolony method, involving uptake of optical brighteners by developing yeast colonies, is described. The method includes the use of incident light microscopy and appears to offer advantages over other detection methods.     

KINETIC STUDIES OF THE DECONTAMINATION OF YEAST SLURRIES WITH PHOSPHORIC ACID AND ACIDIFIED AMMONIUM PERSULPHATE AND A METHOD FOR THE DETECTION OF SURVIVING BACTERIA INVOLVING SOLID MEDIUM REPAIR IN THE PRESENCE OF CATALASE

Destruction of Obesumbacterium proteus in pitching yeast slurries is more efficiently accomplished using an acidified ammonium persulphate wash (0·75% w/v; pH 2·8) than by using phosphoric acid at pH 2·1. The effectiveness of both methods against the lactic acid bacteria, acetic acid bacteria and Enterobacter agglomerans is similar. Material cost savings of up to 60% can be achieved through the use of the acidified ammonium persulphatewash. Economy in the use of materials and optimum process efficiency is achieved by determination of the quantity of acid required to adjust the pH of the yeast slurry before washing. Bacteria surviving the yeast wash can be detected reliably using a plating technique involving solid medium repair in the presence of catalase. A buffered diluent must be used to prepare the inoculum.     

实时荧光PCR方法检测副溶血性弧菌的研究

建立了一种快速检测副溶血性弧菌（vibrio parahaemolyticus,VP）的荧光PCR（Real time polymerase chain re-action）方法。首先,从GenBank中获得副溶血性弧菌种特异性基因不耐热溶血毒素基因tl和直接耐热溶血素毒素基因tdh,用Primer Express2.0设计引物和Taqman荧光探针,在Roche荧光PCR上进行荧光PCR扩增,荧光曲线表明该荧光PCR可特异性地检测副溶血性弧菌,而大肠杆菌等其他14种细菌和空白对照都是阴性;检测方法灵敏度达10cfu/reaction。本研究建立的荧光PCR检测副溶血性弧菌的方法快速、特异性强,灵敏度高,稳定性好,可检测出总的和带tdh毒力基因的副溶血性弧菌,适合于大批量样品的检验,可广泛用于出入境检疫和动物防疫监督部门的疫情监测。     

THE USE OF PESTICIDES IN MALTINGS,BREWERIES AND DISTILLERIES APRIL 1974 - MARCH 1975

A survey of the use of pesticides in maltings, breweries and distilleries during the period April 1974 to March 1975 was made by the Pesticides Survey Group at the Ministry of Agriculture's Pest Infestation Control Laboratory at Slough in collaboration with the Department of Agriculture and Fisheries for Scotland. A breakdown of the insecticides and rodenticides used, including quantities and numbers of users, is given. The results show that in most cases, the official recommended measures to control pests are being followed.     

THE SEPARATION AND IDENTIFICATION OF A DIMER OF CATECHIN OCCURRING IN BEER

A dimer of catechin has been separated from a number of ales, stouts and lagers. This compound has been shown to have the same structure as procyanidin B3, which has previously been isolated from plant sources. It can be conveniently synthesized from dihydroquercetin and catechin.     

THE RAPID DETECTION OF BREWERY CONTAMINANTS BELONGING TO THE GENUS SACCHAROMYCES BY A SEROLOGICAL TECHNIQUE

The cells of contaminant Saccharomyces spp. are rendered fluorescent by means of fluorescein chemically bound to antibody protein. The fluorescent contaminants are observed microscopically, and an estimate of levels of contamination likely to be encountered in the brewery can be obtained within 3 hr. A serum of suitable specificity is obtained by careful cross-absorption with a brewing yeast, and by combining two sera, all brewery contaminants of the genus Saccharomyces so far encountered are detected. Careful selection of the brewing strain used for cross-absorption, and control of the cross-absorption procedure itself, allows the recognition of certain wild-type Sacch. cerevisiae strains.     

RAPID METHODS FOR THE DETECTION OF YEAST AND LACTOBACILLUS BY ATP BIOLUMINESCENCE

Present plating methods for the detection of potential spoilage organisms in packaged beers require 2–3 days for yeast, and 5–7 days for lactic acid bacteria. Simple and inexpensive sterility tests based on bioluminescence have been developed for the detection in broth media of small numbers of yeasts in 1 day, and lactic acid bacteria, in both normal and heat-stressed conditions, in 3 days.     

乳酸菌的固定化方法及其发酵特性的研究

对乳酸菌固定化工艺参数及发酵特性进行了研究,结果表明,乳酸菌包埋法固定最佳工艺条件为:海藻酸钠的浓度为2%,菌体的稀释比例为1:1,CaCl2溶液的浓度为1.5%,菌种的固定化温度为42℃。固定化菌种胶珠含菌量为4.59×109个/g。固定化乳酸菌产酸和耐酸能力强,菌种活力得到保持,具有持久和可重复利用的特点。     

PHENOTYPIC PROPERTIES,METABOLIC ACTIVITIES AND ELECTROPHORETIC PROTEIN PATTERNS OF Klebsiella oxytoca AND Klebsiella pneumoniae STRAINS ISOLATED FROM LAGER BEER BREWERIES

Phenotypic properties, metabolic end products and gel electrophoretic protein patterns of indole-negative and indole-positive Klebsiella pneumoniae strains isolated from beer breweries are reported. Results obtained clearly indicate that the indole positive K. pneumoniae strains represent a distinct group of klebsielleae and that they should be placed in a distinct group of Klebsielleae and that they should be placed in a distinct taxon, namely, Klebsiella oxytoca.     

DETERMINATION OF ETHYL CARBAMATE IN DISTILLED SPIRITS USING NITROGEN SPECIFIC AND MASS SPECTROMETRIC DETECTION

Gas chromatographic methods are described for the determination of naturally occurring ethyl carbamate in distilled spirits at levels as low as 5 ppb. Bottled products, such as whisky, gin and brandy, are extracted in the presence of n-propyl carbamate as internal standard and analysed by capillary column gas chromatography with either nitrogen specific or mass spectrometric detection. A shorter extraction procedure is satisfactory when the more sensitive and selective mass spectrometric detection is used. Direct sample injection without extraction may be used for higher alcoholic strength cask and new-make samples. Analysis of 181 blended Scotch whisky samples indicated ethyl carbamate concentrations ranging from 20 to 75 ppb. Concentrations in 48 malt whiskies ranged from 15–100 ppb. Ethyl carbamate was not detected in gin, vodka and rectified neutral alcohol. All concentrations in bottled product fell below the Canadian limit of 150 ppb in distilled spirits.