The method describes how to determine the content of tetrachloroethene and trichloroethene in drinking water through extraction and gas chromatography.
Water intended for use as an ingredient in the production of beer (brewing liquor) or other foods
This method describes the basic terms used in sensory analysis.
beer, beer-based beverages, non-alcoholic beverages, mineral water
Terms
Aroma:
Aroma represents the overall sensory impression encompassed by the olfactory organs, some of which is perceived in the mouth and thus partly attributed to the sense of taste.
Flavor/Off-flavor:
For the sake of thoroughness, these two terms, which are defined in DIN 10950 part 2 Sensorische Prüfung, allgemeine Grundlagen, are mentioned here. According to definition put forth by DIN, flavor is defined as the “sum of olfactory, gustatory, temperature-related and/or trigeminal and tactile sensations in the mouth”. Off-flavors are sensory stimuli, which are perceived as unpleasant.
Odor:
Organoleptic properties perceived with the olfactory organ(s), whereby certain volatile substances are breathed in through the nose.
Flavour:
The overall sensory impression perceived through the sense of taste in the mouth, throat and nose. The sense of taste can be influenced by thermal or tactile stimuli, through pain or kinesthesia or any combination thereof. According to DIN, flavor is defined as the “sum of olfactory, gustatory, temperature-related and/or trigeminal and tactile sensations in the mouth”.
Mouthfeel:
Aside from the basic tastes, tactile stimuli – detected through haptic perception in the oral cavity – play a role in the sensory perception of comestibles as they are ingested. Tactile stimuli can be divided into the following:
tactile (touch)
kinesthetic (perception of weight, movement, resistance, etc.)
trigeminal (pain)
temperature-dependent
The term “mouthfeel” is often employed to describe haptic perception in the oral cavity. The following sensory attributes of beverages can be detected primarily by means of mouthfeel:
viscosity, rheological properties
liberation of gas, bubble formation, foaming (carbon dioxide)
general after-effects in the mouth (refreshing, warming, thirst-quenching)
Aftertaste:
The sensory impression, which remains in the mouth, once a beverage has been swallowed. This is often employed as a criterion for the sensory evaluation of beverages.
An aftertaste described as “harmonious” provides incentive to continue drinking.
Orthonasal perception of odors:
Sensory perception commonly referred to as “smelling”. Odorants in the air enter the nasal cavity through the external nares, or nostrils, during the act of breathing. From there, the odorants are transported to the receptor cells where olfactory perception occurs.
Retronasal perception of odors:
Retronasal (lat. retro: “backwards, back”, nasal: “pertaining to the nose”) perception describes the transport of odorants from the oral cavity into the pharynx, then up through the internal nares and nasal cavity to the olfactory receptor cells. Odors are liberated through the mastication of food and beverages, thus providing olfactory (lat. olfacere: “to smell”) stimulus. The retronasal aroma profile of comestibles may differ from the orthonasal aroma profile owing to various factors (e.g. mastication or saliva).
Fullness:
Fullness is a kinesthetic sensation in the oral cavity, which – as it relates to beer – may range from “watery” to “satiating/excessive”. A frequently used synonym for fullness in beer is the term “body”.
Liveliness:
Liveliness as it pertains to beer is the tactile sensation in the oral cavity induced through the action of carbon dioxide, which may range from “flat/stale” to “gassy”.
A synonym often encountered for liveliness is “effervescence”.
Determination of the fermentation cellar yield in order to monitor brewhouse operations
Wort from the midpoint of chilling/pitching wort
The fermentation cellar yield is calculated using the value determined for the amount of extract contained in a batch of wort relative to the amount of extract present in the raw materials used to produce the wort.
The gelatinization temperature can be determined using a rotary viscometer (e.g., Amylograph or Viscograph, Brabender GmbH & Co. KG, Germany [4] or a Rapid-Visco-Analyser, RVA, Perten Instruments, a PerkinElmer Company, USA [8]).
A suspension consisting of a finely ground sample and water is produced, whose precise mixing ratio should correspond to the analysis protocol for the adjunct in question. However, since for many cereals and pseudocereals no official analysis protocol exists, the initial weight for the adjuncts listed in table 2 has been determined empirically [3].
Once the suspension is prepared it is attempered according to a pre-programmed temperature/time program, and the viscosity is determined on a continuous basis by means of a rotor and a rotary torque measurement (fig. 1). When gelatinization begins, an increase in the viscosity is registered, and the corresponding sample temperature is defined as the gelatinization temperature. The standard evaluation criterion (PT) is a viscosity increase of at least 24 cP (≙ mPas) within six seconds.
Barley intended for the production of malt is to be evaluated on the basis of the characteristics described below.
visual assessment
This method describes how to determine whether kernels are cracked as part of the visual and manual inspection of a lot of barley.
Barley intended for the production of malt is to be evaluated on the basis of the characteristics described below.
Visual assessment