In the present study, pollen-identical pure manuka and kanuka honeys and an Australian jelly bush honey were analyzed for the nonvolatiles by UHPLC-PDA-MS/MS and for the volatiles by HS-SPME-GC/MS. A chromatographic profile matchup by means of characteristic marker compounds achieved a clear discrimination between manuka, kanuka, and jelly bush honey. UHPLC-PDA profiles of manuka honey show leptosin, acetyl-2-hydroxy-4-(2-methoxyphenyl)-4-oxobutanate, 3-hydroxy-1-(2-methoxyphenyl)-penta-1,4-dione, kojic acid, 5-methyl-3-furancarboxylic acid, and two unknown compounds as prominent, kanuka honey was characterized by 4-methoxyphenyllactic acid, methyl syringate, p-anisic acid, and lumichrome. 2-Methylbenzofuran, 2'-hydroxyacetophenone, and 2'-methoxyacetophenone were markant volatiles for manuka honey, whereas kanuka honey was characterized by 2,6,6-trimethyl-2-cyclohexene-1,4-dione, phenethyl alcohol, p-anisaldehyde, and an unknown compound in HS-SPME-GC/MS. The jelly bush honey differed from the manuka honey by higher contents of 2-methoxybenzoic acid and an individual unknown substance in the PDA profile and by lower intensities of 2'-methoxyacetophenone, higher concentrations of cis-linalool oxide, and 3,4,5-trimethylphenol in the HS-SPME-GC/MS profile.

New Zealand manuka honey is well-known for its unique antibacterial activity. Due to its high price and limited availability, this honey is often subject to honey fraud. Two pteridine derivatives, 3,6,7-trimethyl-2,4(1H,3H)-pteridinedione and 6,7-dimethyl-2,4(1H,3H)-pteridinedione, have now been identified in New Zealand manuka honey. Their structures were elucidated by LC-QTOF-HRMS, NMR, and single-crystal X-ray diffraction after isolation via semipreparative HPLC. Their marker potential for authentic manuka honey was proved as both substances were detectable in neither the pollen-identical kanuka honey nor the nine other kinds of monofloral New Zealand honey analyzed (clover, forest, kamahi, pohutukawa, rata, rewarewa, tawari, thyme, and vipers bugloss). The fluorescence property of the pteridine derivatives can be used as an easy and fast TLC screening method for the authentication of genuine manuka honey. 6,7-Dimethyl-2,4(1H,3H)-pteridinedione has been described for the first time.

According to legislation, unifloral honeys are characterized by their organoleptic, physicochemical, and microscopic properties. Melissopalynology is the established method for identifying the pollen taken up with the floral nectar by forager bees and is used for authentication of the nectar sources in honey. For cornflower honey (Centaurea cyanus), the pollen input does not correlate with the nectar input, because the nectar is produced both in floral and in extrafloral nectaries. The well-known cornflower marker lumichrome has now also been detected in the extrafloral nectar. Therefore, lumichrome is a suitable marker substance for cornflower honey. Four different methods for the sole analysis of lumichrome in honey were validated and compared. Studies over nine years have shown that unifloral cornflower honey should contain approximately 35 mg/kg lumichrome. For a further differentiated cornflower honey specific verification, other nonvolatile compounds like 7-carboxylumichrome and volatiles, such as 3,4-dihydro-3-oxoedulan I and 3,4-dihydro-3-oxoedulan II, should be analyzed. This enables a more specific accuracy for the classification of unifloral cornflower honey.

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Für Biertreber, das mengenmäßig größte Nebenprodukt im Brauprozess, soll als Zwischenstand eines laufenden Forschungsprojekts ein über den bekannten Stand der bisherigen Trebernutzung hinausgehender Verwertungspfad vorgestellt werden. Der Fokus liegt hierbei auf einer anpassbaren, selektiven Abtrennung der noch enthaltenen Wertstoffe aus dem Treberpresswasser. Es werden Versuche zur gezielten Abtrennung der Inhaltsstoffe für eine spätere stoffliche Nutzung mittels Mikro-, Ultra-und Nanofiltration vorgestellt. Die Eignung verschiedener Membranen wird dabei basierend auf der erreichten Permeabilität sowie dem Rückhalt von Wertkomponentenklassen wie Proteinen und Polyphenolen bewertet. Es konnte u. a. gezeigt werden, dass bei der Mikrofiltration mithilfe einer rotierenden Membran Permeatflüsse im Bereich der kommerziellen Bierfiltration erreichbar sind.A new utilization concept for brewers' spent grains, the main byproduct of the brewing industry, is introduced. First results from an ongoing research project beyond the actual state of the art of brewers' spent grains usage are presented. It is focused on developing an adaptable selective separation procedure of valuable components from press water arising by mechanical dewatering of brewers' spent grains for the use as food additive. Experimental results on micro-, ultra-and nanofiltration for specific separation of the ingredients focused on substance classes are presented. The membrane applicability is evaluated by the membrane permeability and by the retention of valuable components like proteins and polyphenols. Results showed that the microfiltration of press water with a rotating membrane is comparable to commercial beer microfiltration in terms of permeate flux.