Search: Lg foam tester

In determining the foam stability with the Steinfurth Foamtester SFT, the time required for the foam to collapse in a graduated cylinder is measured.

The pressurization is carried out in such a way that the container does not require degassing. The attempered beer is injected into the measuring cylinder through a nozzle, and in the process, foam is formed. The foam stability is determined by several optical sensors detecting the time necessary for the beer/foam interface to pass by them. The precise metering of a predetermined quantity of beer, the entire process of executing the analysis and displaying the results as well as cleaning and conditioning of the measurement cylinder are performed automatically.

In an Lg foam tester, the foam stability is determined by measuring the time it takes for the foam to collapse in a glass cylinder.

The foam is produced by pressing a constant beer volume through a nozzle (Ø 0.6 mm). The precise metering of a predetermined quantity of beer is achieved by time-controlled operation of the valve in conjunction with pressurizing the sample bottle to 2.5 bar (± 5 mbar). As the foam collapses, the height is measured optically in the glass cylinder [1]. 

The aromatic alcohols in beer are isolated using solid-phase extraction and are detected using gas chromatography-mass spectrometry.

According to the DLG scheme of sensory evaluation for beer, the criteria aroma, flavor, fullness, liveliness and the quality of the bitterness are each evaluated on a five-point scale. Any faults in the aroma or flavor are to be described, although a number of descriptors are already provided on the form. The fullness is assessed in accordance with the parameters of the particular beer style. In evaluating the bitterness, quality is of prime importance, not intensity.

The form for the sensory analysis of beer-based beverages as part of the DLG Quality Assessment for Beer is provided for evaluating the following criteria:
Aroma:
Products are considered to be flawless if they possess pure, clean, typically fruity aromas. If a product is overly aromatized and/or oxidized or stale, points should be subtracted from its score. 

Purity of Flavor:
A pure, clean, aromatic flavor is also desirable here, and if coupled with a well-balanced sugar to acid ratio, a perfect score is given. If a product is overly aromatized, exhibits off-flavors or is out of balance, i.e. if one of the relevant building blocks (sweet, sour, bitter) central to the flavor of a beer-based beverage is too pronounced, then this defect should be recorded on the form.

Liveliness:
The liveliness is assessed according to the five-point scale, the upper and lower limits of which are designated as “very lively” (5) to “very flat” (1).

Harmony:

The overall impression is evaluated under “harmony”.
 

The DLG Score Sheet for Water concentrates primarily on the attributes of aroma and flavor. The appearance is evaluated for possible aberrations through verbal remarks.

Aroma

The highest number of points is awarded for a pure aroma impression without off-aromas.

A lower score is given for the evaluations “still pure” or “off-aroma”, whereby the latter must be accompanied by a specific description.

In extreme cases, the product can be classified as “not able to be evaluated”. Additional documentation of off-aromas can be recorded under the “other faults” section.

Flavor 
From the perspective of the DLG, a water sample will receive the highest number of points when it tastes “pure, typical” and “balanced”. Deviation from these attributes, the absence of freshness, and also a limited, one-sided character accompanied by off-flavors should result in lower scores. 

Due to the nature of their very hedonistic and general character, the terms “not completely true to style”, “not completely fresh” and “not completely balanced” are difficult to use objectively.