Kajetan Trost

Effects of Temperature and Photoperiod on Yield and Chemical Composition of Northern and Southern Clones of Bilberry (Vaccinium myrtillus L.)

After pollination outdoors, individual bilberry plants from two Northern and two Southern clones were studied for climatic effects on berry yield and quality in a controlled phytotrone experiment at 12 and 18 °C. At each temperature, the following light treatments were tested: (1) 12 h natural light, (2) 24 h natural light, and (3) 24 h natural light plus red light. The first experimental year there was no difference in yield between temperatures; however, the second experimental year the berry yields was significantly higher at 18 °C. Berry ripening was faster in the Northern than in the Southern clones at 12 °C. Northern clones also showed significantly higher contents of total anthocyanins, all measured anthocyanin derivatives, total phenolics, malic acid and sucrose. Metabolic profiling revealed higher levels of flavanols, hydroxycinnamic acids, quinic acid and carbohydrates at 12 °C.

Use of non-conventional yeast improves the wine aroma profile of Ribolla Gialla

Consumer wine preferences are changing rapidly towards exotic flavours and tastes. In this work, we tested five non-conventional yeast strains for their potential to improve Ribolla Gialla wine quality. These strains were previously selected from numerous yeasts interesting as food production candidates. Sequential fermentation of Ribolla Gialla grape juice with the addition of the Saccharomyces cerevisiae T73 Lalvin industrial strain was performed. Zygosaccharomyces kombuchaensis CBS8849 and Kazachstania gamospora CBS10400 demonstrated positive organoleptic properties and suitable fermentation dynamics, rapid sugar consumption and industrial strain compatibility. At the same time, Torulaspora microellipsoides CBS6641, Dekkera bruxellensis CBS2796 and Dekkera anomala CBS77 were unsuitable for wine production because of poor fermentation dynamics, inefficient sugar consumption and ethanol production levels and major organoleptic defects. Thus, we selected strains of K. gamospora and Z. kombuchaensis that significantly improved the usually plain taste of Ribolla wine by providing additional aromatic complexity in a controlled and reproducible manner.

Early versus late leaf removal strategies for Pinot Noir (Vitis vinifera L.): effect on colour-related phenolics in young wines following alcoholic fermentation

BACKGROUND The widely adopted viticultural practice of late (véraison) leaf removal is now losing many of its advantages as a result of todays warmer vineyard conditions. With the aim of seeking a good alternative, the influence of earlier leaf removals (at pre-flowering and berry-set) on colour-related phenolics in young Pinot Noir wines was investigated in the years 2009 and 2010. RESULTS Total flavonols in 2009 wines were 71 and 52% higher in case of véraison and berry-set treatments respectively as compared with untreated controls, while in 2010 the average content of flavonols was highest with pre-flowering leaf removal (75% higher than controls). The anthocyanin content in 2009 wines was 18 and 11% higher in case of véraison and berry-set treatments respectively and was favoured by early leaf removals in 2010 (50 and 43% higher in case of berry-set and pre-flowering treatments respectively) as compared with controls. Changes in hydroxycinnamic acid profiles were shown to be greatest in 2010 wines resulting from early leaf removal treatments. Promoted formation of vitisin A-like pigments in 2010 leaf removal treatments was observed during fermentation. CONCLUSIONS The phenolic profiles of grapes/wines were affected by leaf removal timing, although differently in two (extremely different) seasons. Earlier leaf removal strategies showed some promising results, with good proportions mainly of flavonols and anthocyanins, retained also in young wines. Vitisins A in wines were positively affected by all leaf removals.

An indirect assay for volatile compound production in yeast strains

Traditional flavor analysis relies on gas chromatography coupled to mass spectrometry (GC-MS) methods. Here we describe an indirect method coupling volatile compound formation to an ARO9-promoter-LacZ reporter gene. The resulting β-galactosidase activity correlated well with headspace solid phase micro extraction (HS/SPME) GC-MS data, particularly with respect to the formation of rose flavor. This tool enables large-scale screening of yeast strains and their progeny to identify the most flavor active strains.

Nutraceutical Improvement Increases the Protective Activity of Broccoli Sprout Juice in a Human Intestinal Cell Model of Gut Inflammation

Benefits to health from a high consumption of fruits and vegetables are well established and have been attributed to bioactive secondary metabolites present in edible plants. However, the effects of specific health-related phytochemicals within a complex food matrix are difficult to assess. In an attempt to address this problem, we have used elicitation to improve the nutraceutical content of seedlings of Brassica oleracea grown under controlled conditions. Analysis, by LC-MS, of the glucosinolate, isothiocyanate and phenolic compound content of juices obtained from sprouts indicated that elicitation induces an enrichment of several phenolics, particularly of the anthocyanin fraction. To test the biological activity of basal and enriched juices we took advantage of a recently developed in vitro model of inflamed human intestinal epithelium. Both sprouts’ juices protected intestinal barrier integrity in Caco-2 cells exposed to tumor necrosis factor α under marginal zinc deprivation, with the enriched juice showing higher protection. Multivariate regression analysis indicated that the extent of rescue from stress-induced epithelial dysfunction correlated with the composition in bioactive molecules of the juices and, in particular, with a group of phenolic compounds, including several anthocyanins, quercetin-3-Glc, cryptochlorogenic, neochlorogenic and cinnamic acids.

Anti‐Campylobacter activity of resveratrol and an extract from waste Pinot noir grape skins and seeds, and resistance of Camp. jejuni planktonic and biofilm cells, mediated via the CmeABC efflux pump

To define anti‐Campylobacter jejuni activity of an extract from waste skins and seeds of Pinot noir grapes (GSS), resveratrol and possible resistance mechanisms, and the influence of these on Camp. jejuni morphology.

METABOLITE PROFILING OF BILBERRIES (VACCINIUM MYRTILLUS L.)

Norwegian Institute for Agricultural and Environmental Research, Bioforsk Nord Holt, Box 2284, N-9269 Tromso, Norway The Plant Biocentre, Department of Biology, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway Department of Biology, University of oulu, PoB 3000, FIN-90014 oulu, Finland University of Nova Gorica, Wine Research Centre, Vipavska 11c, SI-5270 Ajdovscina, Slovenia Institute of Biology, University of Tromso, N-9037 Tromso, Norway

Evaluation of cloudberry (Rubus chamaemorus L.) clones for selection of high-quality varieties

Abstract Two female and two male cultivars of cloudberry (Rubus chamaemorus L.) have previously been released as a result of clone evaluation at the Norwegian Institute for Agricultural and Environmental Research. Selection criteria have been number of pistils or stamens per flower, number of flowers and number of shoots per m2. Recently two groups of clones have been evaluated with the aim of finding new cultivars for release. The clones were collected at different locations in Norway, as well as in England and at Svalbard. Results from harvesting in 2005 to 2008 show large genetic variation in all evaluated traits and indicate good production potential for some of the tested clones. Previously released ‘Fjellgull’ and ‘Fjordgull’ are confirmed as stable and high producing. Of the clones evaluated for the first time, especially clone 102 and clone 306 are possible contenders for release. In addition to prior selection criteria based on berry yield, berry contents also have been analysed. The results indicate that clones with a northern origin have higher levels of total phenols, total anthocyanins and carotenoids than clones of a southern origin.

Host: Microbiome co-metabolic processing of dietary polyphenols – An acute, single blinded, cross-over study with different doses of apple polyphenols in healthy subjects

Apples are one of the most commonly consumed fruits and their high polyphenol content is considered one of the most important determinants of their health-promoting activities. Here we studied the nutrikinetics of apple polyphenols by UHPLC-HRMS metabolite fingerprinting, comparing bioavailability when consumed in a natural or a polyphenol-enriched cloudy apple juice. Twelve men and women participated in an acute single blind controlled crossover study in which they consumed 250 mL of cloudy apple juice (CAJ), Crispy Pink apple variety, or 250 mL of the same juice enriched with 750 mg of an apple polyphenol extract (PAJ). Plasma and whole blood were collected at time 0, 1, 2, 3 and 5 h. Urine was collected at time 0 and 0-2, 2-5, 5-8, and 8-24 h after juice consumption. Faecal samples were collected from each individual during the study for 16S rRNA gene profiling. As many as 110 metabolites were significantly elevated following intake of polyphenol enriched cloudy apple juice, with large inter-individual variations. The comparison of the average area under the curve of circulating metabolites in plasma and in urine of volunteers consuming either the CAJ or the PAJ demonstrated a stable metabotype, suggesting that an increase in polyphenol concentration in fruit does not limit their bioavailability upon ingestion. Faecal bacteria were correlated with specific microbial catabolites derived from apple polyphenols. Human metabolism of apple polyphenols is a co-metabolic process between human encoded activities and those of our resident microbiota. Here we have identified specific blood and urine metabolic biomarkers of apple polyphenol intake and identified putative associations with specific genera of faecal bacteria, associations which now need confirmation in specifically designed mechanistic studies.

Levels of individual anthocyanins and hydroxycinnamic derivates in selected clones of cloudberry (Rubus chamaemorus)

Abstract Cloudberry (Rubus chamaemorus) is a dioecious perennial shrub growing on peat land. The berries are a combined fruit with a color ranging from yellow to orange and bright red. Berries are highly valued in the Nordic countries and berries with orange to red color are preferred. Cultivation and breeding has started, and four Norwegian varieties are on the market. These clones were selected on the basis of good shoot production (both sexes), good pollinators (males), and big berries (females). Recently, berry quality has been introduced in breeding programs as a trait for selection. In this study we present the variation in levels of individual anthocyanins and hydroxycinnamic derivates between different clones of cloudberry. Both levels of anthocyanins and hydroxycinnamic derivates varied considerably between the different clones. The most abundant anthocyanin was cyanidin 3-glucoside, followed by cyanidin 3-rutinoside. One single clone (AN1372) from Andøya in Northern Norway had the highest levels of all the analyzed anthocyanins. Among the two analyzed hydroxycinnamic acids, p-coumaric acid presented the highest ratio in all analyzed berries. Differences between different years were relatively high, but not consistent. Levels of caffeic acid did not vary much between clones. The results indicate a genetic basis for the variation between clones, but since numbers of samples were few and sampling only were done during two growth seasons, further analysis will be needed to examine the variation and genetic basis of anthocyanin composition of cloudberry.