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Sensory evaluations were conducted on wheat-flour porridge and baked-bread samples, made from wheat varieties with known odour and flavour variations. The purpose was to determine if these odour and flavour variations were expressed in baked-bread. In all, 24 wheat varieties were used for porridge evaluation, from these eight were selected for bread evaluation. Porridge and bread results were compared. Variations were found in both evaluations. Five odour- and nine flavour descriptors were found to be common to both wheat porridge and bread. The results for two descriptors: “cocoa” and “oat porridge” were correlated between the wheat porridge and bread samples. Analysis of whole-meal and low-extraction samples revealed that the descriptors “malt”, “oat-porridge”, “ollebrod”, “cocoa” and “grain” mostly characterized wheat bran, while descriptors for “maize”, “bean-shoots”, “chamomile”, “umami”, and “fresh grass” mostly characterized wheat endosperm. Low-extraction bread made from four different varieties also differentiated for five odour- and six flavour descriptors. These results indicate that variations in wheat flavour and odour directly affect bread flavour and odour even in low-extraction bread. This knowledge is important to the baking industry and to plant breeders as wheat aroma could possibly become a future quality parameter in breeding.

The consumers of today have an increasing interest in high quality bread with appealing aroma. The scope of this work is to investigate how aroma in wheat bread crumb is influenced by different fermentation conditions: amount of yeast (20, 40 and 60 g/kg flour) and fermentation temperature (5, 15 and 35 °C). Dough samples were fermented to equal height and baked, and the aroma compounds from the bread were extracted by dynamic headspace extraction and analyzed by gas chromatography–mass spectrometry. Quantification of the aroma compounds was performed by multiple headspace extraction. The most aroma active compounds identified were 3-methylbutanal, (E)-2-nonenal, 3-methyl-1-butanol, and 2,3-butanedione. Increasing the yeast concentration was found to increase formation of the majority of the compounds formed from the yeast metabolism, with 2,3-butanedione and phenylacetaldehyde as the most aroma active compounds. High fermentation temperature (15 and 35 °C) increased formation of many lipid oxidation compounds, with hexanal and heptanal having the highest odor activity values. Low fermentation temperature (5 °C) was found to increase formation of the three esters ethyl acetate, ethyl hexanoate, and ethyl octanoate, with ethyl hexanoate having the highest odor activity value. The odor activity values of the esters were generally low.

The aim of the present study was to determine the contents of ascorbic acid in old Danish apple cultivars and in commercially available apple juices. Ascorbic acid was determined using the 2,6-dichloroindophenol method. The ascorbic acid content of the 71 analysed apple cultivars ranged from less than 1 to 27 mg/100 mL, with an average of 6.4 mg/100 mL. Preliminary results showed that upon pressing of apples the ascorbic acid was readily degraded. The levels of ascorbic acid found in the 18 commercial apple juices were negligible, the highest level was 2.6 mg/100 mL, but most were below 1 mg/100 mL. Hence to benefit from ascorbic acid in apples the fruits have to be eaten unprocessed.

Boiled potato off-flavour is a cardboard-like note, that develops within hours when boiled potatoes are stored. Using a panel of four professional judges, it was verified that a clearly detectable off-flavour develops during the storage of boiled potatoes. Two different isolation methods (direct extraction and vacuum distillation/extraction) in combination with GC-MS and GC-sniffing were applied to the same freshly boiled and stored boiled potatoes. Eight compounds, (pentanal, hexanal, nonanal, (E)-2-octenal, 2,4-heptadienal, (E)-2-nonena, (E,E)-2,4-nonedienal and 2,4-decadienal) were appointed as potential contributors to the off-flavour, since these compounds could be detected during GC-sniffing, and increased in concentration during storage. The eight compounds, that most probably appear as a result of lipoxygenase initiated oxidation of linoleic and linolenic acid during the boiling process, were quantified in freshly boiled and stored boiled potatoes.