MODIFIED INDIRECT CONDUCTIMETRIC TECHNIQUE FOR DETECTING LOW POPULATIONS OF YEASTS IN BEVERAGE CONCENTRATES AND CARBONATED BEVERAGES

被引：9

作者：

DEAK, T ^{[1
]}

BEUCHAT, LR ^{[1
]}

机构：

[1] UNIV GEORGIA, DEPT FOOD SCI & TECHNOL, CTR FOOD SAFETY & QUAL ENHANCEMENT, GRIFFIN, GA 30223 USA

来源：

FOOD MICROBIOLOGY | 1995年 / 12卷 / 02期

关键词：

D O I：

10.1016/S0740-0020(95)80093-X

中图分类号：

Q81 [生物工程学（生物技术）]; Q93 [微生物学];

学科分类号：

071005 ; 0836 ; 090102 ; 100705 ;

摘要：

The indirect conductimetric method for detecting yeast activity in foods was modified to increase sensitivity and rapidity for detecting yeast activity in preserved beverage concentrates and carbonated beverages. Nine strains of Zygosaccharomyces and Brettanomyces were isolated from spoiled beverage concentrates and carbonated beverages. A 10 fold dilution of inoculated beverage concentrate in 0.5% tryptone glucose yeast extract broth supplemented with 0.1% Tween 80, followed by pre-incubation under constant aeration at 25-degrees-C for 24 h before subjecting to conductimetric assay, significantly (P < 0.05) decreased the total time necessary for detecting these yeasts. Initial viable yeast populations in the range of 10(-1)-10-degrees cfu ml-1 in beverage concentrates can be detected within 72-144 h. The threshold limit for detection is in the range of 10(4)-10(5) cells ml-1. Low populations (one per 10 ml) of yeasts in carbonated beverages can be detected by collecting cells by filtration before subjecting to conductimetric assay, thus facilitating application of the technique for analysing large volumes of product.

引用

页码：165 / 172

页数：8

共 17 条

[1]

Adams M.R., Bryan J.J., Thurston P.J., A medium designed for monitoring pitching yeast contamination in beer using conductimetric technique, Lett. Appl. Microbiol., 8, pp. 55-58, (1989)

[2]

Bolton F.J., An investigation of indirect conductimetry for detection of some food-borne bacteria, J. Appl. Bacteriol., 69, pp. 655-661, (1990)

[3]

Connolly P., Lewis S.J., Corry J.E.L., A medium for the detection of yeasts using a conductimetric method, Int. J. Food Microbiol., 7, pp. 31-40, (1988)

[4]

Deak T., Foodbome yeasts, Advan. Appl. Microbiol., 36, pp. 179-278, (1991)

[5]

Deak T., Beuchat L.R., Identification of foodbome yeasts, J. Food Prot., 50, pp. 243-264, (1987)

[6]

Deak T., Beuchat L.R., Comparison of conductimetric and traditional plating techniques for detecting yeasts in fruit juices, J. Appl. Bacteriol., 75, pp. 546-550, (1993)

[7]

Deak T., Beuchat L.R., Evaluation of the indirect conductance method for the detection of yeasts in laboratory media and apple juice, Food Microbiol, 10, pp. 255-262, (1993)

[8]

Easter M.C., Gibson D.M., Detection of microorganisms by electrical measurements, Rapid Methods in Food Microbiology, pp. 57-100, (1989)

[9]

Fleischer M., Shapton N., Cooper P.J., Estimation of yeast numbers in fruit mix for yoghurt, J. Soc. Dairy Technol., 37, pp. 63-65, (1984)

[10]

Henschke D.A., Thomas D.S., Detection of wine-spoiling yeasts by electrometric methods, J. Appl. Bacteriol., 64, pp. 123-133, (1988)

← 1 2 →