Skip to Content
Merck
All Photos(2)

Key Documents

17222

Millipore

WL Nutrient Agar

suitable for microbiology, NutriSelect® Plus,

for cultivation of microorganisms encountered in the brewing and fermentation industries

Synonym(s):

Wallerstein Laboratory Nutrient Agar

Sign Into View Organizational & Contract Pricing


About This Item

UNSPSC Code:
41171605
NACRES:
NA.74

Quality Level

sterility

non-sterile

form

powder

shelf life

limited shelf life, expiry date on the label

composition

agar, 20 g/L
bromocresol green, 0.022 g/L
calcium chloride, 0.125 g/L
casein enzymic hydrolysate, 5 g/L
dextrose, 50 g/L
ferric chloride, 0.0025 g/L
magnesium sulfate, 0.125 g/L
manganese sulfate, 0.0025 g/L
monopotassium phosphate, 0.55 g/L
potassium chloride, 0.425 g/L
yeast extract, 4 g/L

manufacturer/tradename

NutriSelect® Plus

technique(s)

microbiological culture: suitable

final pH

5.5±0.2 (25 °C)

application(s)

bioburden testing
food and beverages

microbiology

suitability

nonselective and differential for Candida spp.
nonselective and differential for Escherichia coli
nonselective and differential for Lactobacillus spp.
nonselective and differential for Pichia spp.
nonselective and differential for Proteus spp.
nonselective and differential for Saccharomyces spp.
nonselective and differential for Zygosaccharomyces spp.
nonselective and differential for bacteria (General Media)
nonselective and differential for coliforms
nonselective and differential for molds (General Media)
nonselective and differential for yeasts (General Media)

General description

WL (Walerstein Laboratory) media follow the formula described by Green and Gray for the examination of materials related to brewing and for industrial fermentations containing mixed flora of yeasts and bacteria. Yeast extract is a source of vitamins, amino acids and trace elements. Casein enzymic hydrolysate provides nitrogen, amino acids and carbon. Dextrose is the main carbon and energy source. Potassium phosphate is the buffering agent. Several salts in the medium provide essential ions and help to maintain osmotic balance. Bromcresol green acts as pH indicator and agar as solidifying agent. WL Nutrient Agar is used for the examination of materials encountered in brewing and for industrial fermentations containing mixed flora of yeasts and bacteria.

Application

WL Nutrient Agar is suitable:
  • for reviving yeast stock cultures and for population dynamics studies post fermentation
  • for morphological characterization of yeast isolated from cheese
  • for plating fermented wine for yeast species isolation

Preparation Note

Suspend 80.25 g in 1 litre distilled water. Boil to dissolve the medium completely. Sterilize by autoclaving at 121°C for 15 minutes. If desired, to obtain a pH of 6.5, add 1% solution of sodium bicarbonate.

Footnote

We offer two media types: the superior granulated GranuCult® and the cost-efficient powdered NutriSelect® culture media, depending on your needs.
The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.

Legal Information

GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany
NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany

Storage Class Code

11 - Combustible Solids

WGK

WGK 3

Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Choose from one of the most recent versions:

Certificates of Analysis (COA)

Lot/Batch Number

Don't see the Right Version?

If you require a particular version, you can look up a specific certificate by the Lot or Batch number.

Already Own This Product?

Find documentation for the products that you have recently purchased in the Document Library.

Visit the Document Library

Customers Also Viewed

The impact of Saccharomyces cerevisiae on a wine yeast consortium in natural and inoculated fermentations
Bagheri B, et al.
Frontiers in Microbiology, 8, 1988-1988 (2017)
Selection of autochthonous Saccharomyces cerevisiae strains for production of typical Pinot Gris wines.
Schvarczova E, et al.
Journal of Food & Nutrition Research, 56(4) (2017)
The rapid detection of brewery spoilage micro-organisms
Harrison J, et al.
Journal of the Institute of Brewing, 80(4), 390-398 (1974)
Paper read at American Society of Brewing Chemists Meeting
Green, SR and Gray, PP
Wallerstein Laboratories Communications, 12, 43-43 (1950)
Characterisation of yeast flora isolated from an artisanal Portuguese ewe's cheese
Malfeito-Ferreira M, et al.
International Journal of Food Microbiology (2000)

Articles

Traditional methods are based morphology, staining methods, enzyme reactions (metabolism) and diverse media.

Cost-effective molecular biology method for lactobacilli detection is presented as an alternative to PCR-based methods.

Cost-effective molecular biology method for lactobacilli detection is presented as an alternative to PCR-based methods.

Cost-effective molecular biology method for lactobacilli detection is presented as an alternative to PCR-based methods.

See All

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service