ABV (Alcohol by Volume) is required for bottling and Plato for taxation purposes in NL . Legal requirement is to be within 0.5% ABV for bottling and there are benefits to a precise reading if you are close to the tariff boundaries. 

Bitterness in beer comes from Humulus lupulus, the hops flower. The alpha-acids that are extracted from the flower are what create that iconic bitter taste in beers like India Pale Ales (IPA’s). Furthermore, hops act as a preservative and have antimicrobial properties. The Lab uses extraction with organic solvents to quantify the bittering components in the sample. Reports are provided in IBU’s (international bitterness units), which represent the concentration of hops acid in parts per million (ppm). 

When malted grains are boiled starch is broken down into simple sugars. Then, during fermentation, yeast utilize these sugars and create alcohol. Carbohydrates in beer are the sugars that remain after fermentation. The Lab measures carbohydrate content via colorimetric tests on a spectrophotometer. 

Beer colour is the first characteristic noticed by customers and is usually an indicator of the style and flavour of the brew. Colour originates mainly from the malt, pH, wort boiling, yeast strain, fermentation, oxidation, colorants (like caramel), and filtering. Colour is measured via spectrophotometer and reported in EBC(European) units. The most common beer colour is a pale amber, EBC c.12. 

Diacetyl is a flavour compound present in most beers to some extent and imparting aroma characteristics described as butter, butterscotch, or buttermilk when detected above its flavour threshold of 0.04 mg/l. Diacetyl (butane 2,3 dione) is generated as a by-product of amino-acid metabolism in yeast during fermentation. Diacetyl is tested via spectrophotometry in our lab. 

pH is a measurement of acidity. This measurement is critical because particular enzymes, yeasts, and brewing reactions all require a specific pH range to function effectively. In beer, low pH is often an indicator of lactic acid formation by contaminant bacteria by Lactobacillus species. However, sometimes Lactobacillus is added to a specialty brew to achieve a desired taste, in which case pH may be used for confirmation. 

Polyphenols in beer are important because of their antioxidant properties, role in haze formation, and colloidal stability—in essence: the look of beer. Polyphenols also contribute to astringency, an essence of “dryness”, in the beer. Many polyphenols have been linked to the prevention of cancer and cardiovascular disease. For the craft brewer, polyphenol management requires a delicate balance—too much or too little can cause “off flavours” or create a “murky” beer. Finally, shelf-life is also affected by polyphenol content. Polyphenols are expressed in mg/L. 

Concentrations above 350 ppm are unsafe for human consumption. Sulphur dioxide is an allergen, has a strong aroma, and a low taste threshold. The smell and taste of sulphur dioxide can be detected even in miniscule amounts – even at concentrations of parts per billion. Sulphur compounds are one of the primary causes of “off flavours” in beer, especially in lighter beers. Sulphur dioxide is expressed in mg/L. 

Protein content in beer affects viscosity, foam stability, and haze formation. The Lab analyses protein content via colorimetric assay (primarily Bradford method). On average, a domestic 12-oz beer contains 1.6 g of protein. 

Beta-glucans are important because of their role in haze formation and the viscosity of the beer. Beta-glucans are glucose polymers present in the cell-walls of barley and malt, similar to starch in structure. Although largely contributing to brew turbidity, proper management of beta-glucans is also essential to the brewing process, as it can cause slow run-off from your mash, clog process filters, or even impede the production of fermentable sugars during mashing. Turbidity is expressed in arbitrary units [AU]. 

If spoilage bacteria have been found using our Bacterial Presence test or you have initial suspicions and have requested this, the species of the bacteria can then be identified. The Lab uses a selective media allowing only a specific bacteria to grow to identify the culprit. Different species are very specific to certain types of environments. So, knowing the strain of bacteria present, Lab specialists can deduce the likely source of the contamination in the brewing process. 

A yeast count determines the amount of healthy yeast cells in a given sample. This value is used (1) to calculate how much yeast is used for initial pitching, (2) to ensure the yeast is thriving, and (3) to verify that the yeast is reproducing sufficiently for the fermentation process. Yeast counts are carried out using a light microscope and methylene blue, which marks dead cells to facilitate counting of live cells.