Corrigendum to: Impact of Successive Exploitation of a Saccharomyces pastorianus Starter Culture on Saccharide Uptake Dynamics from Wort (Published: Food Technol. Biotechnol. 59 (1) 16-23 (2021) https://doi.org/10.17113/ftb.59.01.21.6899)

The authors would like to state that they inadvertently omitted one of the authors when preparing the manuscript. The authors of this work are as follows: Miha Ocvirk1, Nataša Kočar Mlinarič2, Peter Raspor3 and Iztok Jože Košir1* 1Slovenian Institute of Hop Research and Brewing, C. Žalskega tabora 2, 3310 Žalec, Slovenia 2Pivovarna Laško Union d.o.o., Pivovarniška ulica 2, 1000 Ljubljana, Slovenia 3Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Sloveni

Preliminary results of variability in mechanical-induced volatile root-emissions of different maize cultivars

The current study was conducted to obtain more information on the specificity and variation of the volatile com¬pounds, which are released from the root system of different lines and hybrids of Zea mays plants. European (12 genotypes) and North American (5 genotypes) genetic material was included (15 maize hybrids and 2 maize inbreds). The results of our study have shown that roots of European and American maize genotypes secrete dif¬ferent relative amounts of linalool, a-caryophyllene and b-caryophyllene, which depend on genotype and on the pretreatment of the roots (various mechanical damages)

Utjecaj uzastopne primjene starter kulture Saccharomyces pastorianus na dinamiku potrošnje šećera iz sladovine

Research background. The production of lager beer includes successive repitchings of a single Saccharomyces pastorianus starter culture. During the beer production process, the yeast is exposed to several stress factors which could affect the fermentation performance. An incomplete fermentation represents a waste of fermentable extract and leads to a beer with higher carbohydrate levels, which could result in a beer with an atypical flavour profile. The aim of the present study is to determine the impact of successive exploitation of a single S. pastorianus starter culture on the wort saccharide uptake dynamics. Experimental approach. The fermentation was monitored during the production of twelve batches of beer, where the starter yeast culture was reused twelve times without any further treatment. The following beer production steps were monitored: wort production, yeast starter culture propagation, primary fermentation, secondary fermentation and the final product. The work was conducted on an industrial scale employing standard process conditions. Results and conclusions. Monitoring of the starter culture viability during successive fermentations indicated no reduction in the viability and vitality of the yeast culture. Monitoring of the fermentable wort saccharide concentrations (glucose, fructose, disaccharides and trisaccharides) revealed a correlation between an improvement in saccharide utilisation and starter culture age. Saccharide uptake efficacy proportionally matched the repitching frequency. Successive exploitation of S. pastorianus starter culture has a positive impact on the dynamics of saccharide utilisation from classical hopped wort and the young beer. Furthermore, the final lager beer contains no residues of fermentable saccharides that could affect the overall quality and flavour profile. Novelty and scientific contribution. Results showed the impact of twelve successive wort fermentations on the dynamics of saccharides uptake that gives brewers important information. The added value of the experiment is all the work done on the industrial scale, with control of all processes and usage of exactly the same raw materials. This study contains usable technological data on the behaviour of saccharides during brewing on the industrial scale, which is not yet found in the literature.Pozadina istraživanja. Proizvodnja lager piva uključuje uzastopnu primjenu („repitching“) pojedinačne starter kulture Saccharomyces pastorianus. Tijekom proizvodnje piva, kvasac je izložen različitim stresnim uvjetima koji utječu na učinkovitost vrenja. Nepotpunim vrenjem se gubi fermentacijski ekstrakt i nastaje pivo s velikim udjelom ugljikohidrata, koje nema tipičan profil okusa. Svrha je ovoga rada bila odrediti utjecaj uzastopne primjene pojedinačne starter kulture S. pastorianus na dinamiku potrošnje šećera iz sladovine. Eksperimentalni pristup. Tijek vrenja je promatran tijekom proizvodnje dvanaest šarži piva u kojima je korištena ista kultura kvasca dvanaest puta, bez dodatne obrade. Praćeni su sljedeći koraci u proizvodnji piva: proizvodnja sladovine, rast kvasca, prvo vrenje, drugo vrenje i krajnji proizvod. Istraživanje je provedeno u industrijskim uvjetima, primjenom standardnih uvjeta proizvodnje. Rezultati i zaključci. Praćenjem rasta starter kulture tijekom uzastopnih vrenja utvrđeno je da nije došlo do smanjenja udjela živih stanica i životnosti kvasca. Izmjerene koncentracije fermentabilnih šećera (glukoze, fruktoze, disaharida i trisaharida) otkrile su da postoji odnos između povećane potrošnje šećera i starosti starter kulture. Učinkovitost potrošnje šećera bila je proporcionalna broju uzastopnih primjena kvasca. Uzastopna primjena starter kulture S. pastorianus pozitivno je utjecala na dinamiku iskorištenja šećera iz sladovine s dodatkom hmelja te iz mladog piva. Dobiveno lager pivo nije sadržavalo ostatke fermentabilnih šećera, koji bi mogli utjecati na kakvoću i okus piva. Novina i znanstveni doprinos. Rezultati prikazuju utjecaj dvanaest uzastopnih vrenja sladovine na dinamiku potrošnje šećera, što je bitna informacija za pivare. Dodatna vrijednost ovog istraživanja je što je ono po prvi put provedeno u industrijskim uvjetima, pri čemu su kontrolirani svi parametri procesa i svaki put je korištena potpuno ista sirovina. Ovo istraživanje sadržava korisne tehnološke podatke o potrošnji šećera tijekom vrenja u industrijskim uvjetima, što dosad nije opisano u literaturi

Phenolic compounds in Geranium dalmaticum (Beck) Rech. f. and G. macrorrhizum L. (Geraniaceae) growing in Croatia

The quantitative analysis of bioactive phenolic compounds was carried out for the first time in aboveground plant parts of Geranium dalmaticum (Beck) Rech. f. and G. macrorrhizum L. (Geraniaceae) from Croatia by means of UV-Vis spectrophotometric methods and HPLC analysis. Both species had similar contents of polyphenolic substances expressed as mg of standard equivalent /g of dried herbal sample: total polyphenols (217.60 ± 1.08 and 215.53 ± 1.10 mg/g), tannins (155.83 ± 0.60 and 157.73 ± 0.61 mg/g), total flavonoids (5.10 ± 0.10 and 5.53 ± 0.10 mg/g), and total phenolic acids (13.27 ± 1.34 and 15.33 ± 0.45 mg/g), respectively for G. dalmaticum and G. macrorrhizum. Only the content of phenolic acids was somewhat higher in G. macrorrhizum but it was not statistically significant (p > 0.05). HPLC analysis showed that, among seven tested phenolic compounds, only quercetin was quantified in G. dalmaticum (0.23 % of dry weight), and rutin in G. macrorrhizum (1.12 % of dry weight). The obtained results represent a useful basis for further research of phytochemicals and biological activities of G. dalmaticum and G. macrorrhizum extracts

Importance of Medical Effects of Xanthohumol, Hop (Humulus lupulus L.) Bioflavonoid in Restructuring of World Hop Industry

Nowadays, the world hop industry is faced with one of the biggest crisis in the history. Permanent decrease of hopping rates in the world beer industry during last 20 years caused many problems to hop producers all around the world. It resulted in the huge surpluses of hop stocks between years 2008 and 2010, the ages known as “years of famine” for hop farmers. The hop contains some compounds having medical, pharmaceutical or biological activities, and xanthohumol is one of them. Xanthohumol is a bioflavonoid whose positive effect is confirmed both in vitro and in vivo experiments. It is successfully used in medical treatment of patients having diseases such as prostate and breasts cancer, osteoporosis, menopausal problems, and even HIV. However, such attributes of hop are strong argument to consider the restructuring of the world hop industry and forming a new supply chain, primarily oriented to the pharmaceutical industry

Phenolic compounds in two subspecies of Drypis spinosa L. (Caryophyllaceae) in Croatia

As a contribution to chemotaxonomic relations, a quantitative analysis of bioactive phenolic compounds was carried out for the first time in Drypis spinosa L. subsp. spinosa and D. spinosa subsp. jacquiniana Murb. et Wettst. ex Murb. in Croatia. Total polyphenols (TP), tannins (T) and total flavonoids (TF) were determined in samples of leaves, stems, and roots using UV-Vis spectrophotometric methods. For the subsp. spinosa, the highest content of TF was in leaves (0.09%), as was the highest amount of TP (2.36%) and T (1.12%). In the subsp. jacquiniana, the highest contents of TF (0.10%), TP (1.96%), and T (0.88%) were measured in stems. Coumaric, ferulic and rosmarinic acid were identified and quantified by HPLC analysis in both subspecies. Quercetin and sinapic acid were identified only in subsp. spinosa, while rutin and naringenin were found only in subsp. jacquiniana. Among them, ferulic acid was identified only in flowers of both subspecies. The results of this study represent a useful basis for further research of phytochemical and eventually phytotherapeutic potential of D. spinosa