Ingunn Øvsthus

Ms. Ingunn Øvsthus


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 December 2015 in Journal of Agricultural and Food Chemistry
Verified
Journal Article
Open access
IØIngunn Øvsthus
Ingunn Øvsthus
TBTor Arvid Breland
Tor Arvid Breland
SHSidsel Fiskaa Hagen
Sidsel Fiskaa Hagen
Kirsten BrandtKirsten Brandt
Kirsten Brandt
AWAnne-Berit Wold
Anne-Berit Wold
RSRandi Seljåsen
Randi Seljåsen
Organic vegetable production attempts to pursue multiple goals concerning influence on environment, production resources, and human health. In areas with limited availability of animal manure, there is a need for considering various off-farm nutrient resources for such production. Different organic and waste-derived fertilizer materials were used for broccoli production at two latitudes (58° and 67°) in Norway during two years. The fertilizer materials were applied at two rates of total N (80 and 170 kg ha–1) and compared with mineral fertilizer (170 kg ha–1) and no fertilizer. Broccoli yield was strongly influenced by fertilizer materials (algae meal < unfertilized control < sheep manure < extruded shrimp shell < anaerobically digested food waste < mineral fertilizer). Yield, but not glucosinolate content, was linearly correlated with estimated potentially plant-available N. However, extruded shrimp shell and mineral NPK fertilizer gave higher glucosinolate contents than sheep manure and no fertilizer. Sensory attributes were less affected by fertilizer material and plant-available N.

8 September 2023 in Fermentation
Verified
Journal Article
Open access
PDF file
UČUrban Česnik
Urban Česnik
MMMitja Martelanc
Mitja Martelanc
IØIngunn Øvsthus
Ingunn Øvsthus
TVTatjana Radovanović Vukajlović
Tatjana Radovanović Vukajlović
AHAdrian Hermes
Adrian Hermes
Lorena ButinarLorena Butinar
Lorena Butinar
Saccharomyces cerevisiae is commonly used for the production of alcoholic beverages, including cider. In this study, we examined indigenous S. cerevisiae and S. uvarum strains, both species commonly found in cider from Hardanger (Norway), for their strain-specific abilities to produce volatile and non-volatile compounds. Small-scale fermentation of apple juice with 20 Saccharomyces strains was performed to evaluate their aroma-producing potential as a function of amino acids (AAs) and other physicochemical parameters under the same experimental conditions. After fermentation, sugars, organic acids, AAs, and biogenic amines (BAs) were quantified using the HPLC–UV/RI system. A new analytical method was developed for the simultaneous determination of nineteen AAs and four BAs in a single run using HPLC–UV with prior sample derivatization. Volatile compounds were determined using HS-SPME-GC-MS. Based on 54 parameters and after the removal of outliers, the nineteen strains were classified into four groups. In addition, we used PLS regression to establish a relationship between aroma compounds and predictor variables (AAs, BAs, organic acids, sugars, hydrogen sulfide (H2S) production, CO2 release) of all 19 strains tested. The results of the VIP show that the main predictor variables affecting the aroma compounds produced by the selected yeasts are 16, belonging mainly to AAs.

30 September 2017 in Nutrient Cycling in Agroecosystems
Verified
Journal Article
Closed access
PDF file
IØIngunn Øvsthus
Ingunn Øvsthus
RSRandi Seljåsen
Randi Seljåsen
ESElizabeth Stockdale
Elizabeth Stockdale
CUChristian Uhlig
Christian Uhlig
TTTorfinn Torp
Torfinn Torp
TBTor Arvid Breland
Tor Arvid Breland

13 August 2024 in Beverages
Verified
Journal Article
Open access
PDF file
IØIngunn Øvsthus
Ingunn Øvsthus
MMMitja Martelanc
Mitja Martelanc
Alen AlbrehtAlen Albreht
Alen Albreht
TVTatjana Radovanović Vukajlović
Tatjana Radovanović Vukajlović
UČUrban Česnik
Urban Česnik
BVBranka Mozetič Vodopivec
Branka Mozetič Vodopivec
Our investigation delves into the previously uncharted territory of cider composition from Norway. This study aimed to obtain an overview of the qualitative and quantitative compositions of general chemical parameters, polyphenols (individual and total expressed as gallic acids equivalents), selected esters, and selected C6-alcohols in ciders with the PDO label Cider from Hardanger. In total, 45 juice and cider samples from the fermentation process were collected from 10 cider producers in Hardanger in 2019, 2020, and 2021. Individual sugars, acids, ethanol, and 13 individual phenols were quantified using HPLC-UV/RI. Seven ethyl esters of fatty acids, four ethyl esters of branched fatty acids, ten acetate esters, two ethyl esters of hydroxycinnamic acids, and four C6-alcohols were quantified using HS-SPME-GC-MS. For samples of single cultivars (‘Aroma’, ‘Discovery’, ‘Gravenstein’, and ‘Summerred’), the sum of the measured individual polyphenols in the samples ranges, on average, from 79 to 289 mg L−1 (the lowest for ‘Summerred’ and highest for ‘Discovery’ and ‘Gravenstein’). Chlorogenic acid was the most abundant polyphenol in all samples. Ethyl butyrate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, ethyl isobutyrate, ethyl 2-methylbutyrate, isoamyl acetate, and hexanol were present at concentrations above the odour threshold and contributed to the fruity flavour of the Cider from Hardanger.