RESUMEN
In brewing practice, the use of the appropriate hop variety is essential to produce consistent and high-quality beers. Yet, hop batches of the same variety cultivated in different geographical regions can display significant biochemical differences, resulting in specific taste- and aroma-related characteristics in beer. In this study, we illustrate the complementarity of genetic and biochemical fingerprinting methods to fully characterize hop batches. Using genotyping-by-sequencing (GBS), a set of 1â¯830 polymorphic single nucleotide polymorphism (SNP) markers generated 48 unique genetic fingerprints for a collection of 56 commercial hop varieties. Three groups of varieties, consisting of somaclonal variants, could not be further differentiated using this set of markers. Biochemical marker information offered added value to characterize hop samples from a given variety grown at different geographical locations. We demonstrate the power of combining genetic and biochemical fingerprints for quality control of hop batches in the brewing industry.
Asunto(s)
Cerveza/análisis , Humulus/genética , Polimorfismo de Nucleótido Simple , Biomarcadores/análisis , Humulus/química , Humulus/clasificaciónRESUMEN
Amadumbe, known as taro is a traditional crop mainly grown for subsistence in Southern Africa. In this study, chemical composition and functional properties of nine amadumbe genotypes grown at two distinct locations were investigated. Carbohydrate contents (73-81%) of amadumbe genotypes were substantially high and varied with growth location. Protein contents ranged from 8-12% and fat was very low (less 1%) in all genotypes. Major minerals in flours were K, P, Mg and Ca, but these were present at varying levels depending on growth locations. Amadumbe flours showed slightly low mucilage contents (6-9%) across genotypes. However, genotypes with higher mucilage contents generally had higher water absorption capacities irrespective of growth locations. Genotype and growth location significantly affected the pasting properties of amadumbe flours. Peak viscosities varied between 83-242 RVU among genotypes. The pasting temperature of the genotypes were fairly high 87-94 °C across genotypes. This study data suggests that differences in environmental temperatures and amounts of rain falls received at growth location during the growing season could be some of the factors responsible for the variations in flour composition and consequently their functionality. Findings from this study are important for future improvement programme and for food application of amadumbe flour.
RESUMEN
¹H NMR spectroscopy and multivariate data analysis were applied to the metabolic profiling and discrimination of wild sea buckthorn (Hippophaë rhamnoides L.) berries from different locations in Finland (subspecies (ssp.) rhamnoides) and China (ssp. sinensis). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) showed discrimination of the two subspecies and different growth sites. The discrimination of ssp. rhamnoides was mainly associated with typically higher temperature, radiation and humidity and lower precipitation in the south, yielding higher levels of O-ethyl ß-d-glucopyranoside and d-glucose, and lower levels of malic, quinic and ascorbic acids. Significant metabolic differences (p<0.05) in genetically identical berries were observed between latitudes 60° and 67° north in Finland. High altitudes (> 2,000 m) correlated with greater levels of malic and ascorbic acids in ssp. sinensis. The NMR metabolomics approach applied here is effective for identification of metabolites, geographical origin and subspecies of sea buckthorn berries.