The bioactive constituents and antioxidant activities of ten selected Brazilian Cerrado fruits.

This study measured the total levels of phenolic, anthocyanin, carotenoid, and tocopherol compounds, and vitamin C in ten fruits from the Brazilian Cerrado: araçá-boi, bacaba, bacupari, biribá, cajuí, curriola, marmelada-espinho, mirindiba, murici, and puçá-preto. Five extracts were prepared from each fruit using solvents with different polarities. The Trolox equivalent antioxidant activity, oxygen radical absorbance capacity, and inhibition of β-carotene bleaching were determined for each extract.

Emission of volatile organic compounds from yellow onion ( L.) bulbs during storage.

Fresh onions ( L.) emit volatile organic compounds (VOCs) naturally in very low concentrations. The aim of the present study was to determine the emission rate of low-boiling VOCs from healthy and naturally infected onion bulbs at 4, 15, and 25 °C and to evaluate the applicability of the VOC method to monitor quality changes during 12 weeks of storage of two cultivars ('Hystand' and 'Hoza') of yellow onions.

Online measurement of temperature and relative humidity as marker tools for quality changes in onion bulbs during storage.

A long shelf life of onions (Allium cepa L.) is of high importance in the onion industry. Onions are dried and stored in large wooden boxes that are difficult to access.

Discriminant analysis of volatile organic compounds of Fusarium oxysporum f. sp. cepae and Fusarium proliferatum isolates from onions as indicators of fungal growth.

Basal rot is a common onion disease and is mainly caused by Fusarium oxysporum f. sp. cepae and Fusarium proliferatum.

Novel non-destructive quality assessment techniques of onion bulbs: a comparative study.

This study was designed to compare the performances of four different non-destructive methods of assessing onion quality, one of which was based on near-infrared spectroscopy, and three of which were based on spectral imaging. These methods involve a combination of wavelengths from visible to near-infrared with different acquisition systems that were applied to discriminate between pre-sorted onions by in situ measurements of the onion surface. Compared with the partial least squares discriminant analysis classification models associated with different methods, hyperspectral imaging (HSI) with both static horizontal and rotating orientation obtained a higher level of sensitivity and specificity with a lower classification error than did other methods.

Noninvasive Determination of Firmness and Dry Matter Content of Stored Onion Bulbs Using Shortwave Infrared Imaging with Whole Spectra and Selected Wavelengths.

A firm texture of dry onions is important for consumer acceptance. Both the texture and dry matter content decline during storage, influencing the market value of onions. The main goal of this study was to develop predictive models that in future might form the basis for automated sorting of onions for firmness and dry matter content in the industry.

Volatile organic compounds as markers of quality changes during the storage of wild rocket.

The quality of leafy green vegetables changes during storage. Leaves become yellow or disintegrate, and an off-odor may develop. In addition, small amounts of volatile organic compounds (VOCs) are released.

Eating Quality of Carrots (Daucus carota L.) Grown in One Conventional and Three Organic Cropping Systems over Three Years.

The eating quality of carrots (Daucus carota L.) was investigated to evaluate the impact of cropping systems (one conventional and three organic systems) and growing years (2007, 2008, and 2009) on root size, chemical composition, and sensory quality. The content of dry matter, sugars, polyacetylenes, and terpenes as well as the sensory quality and root size were related to the climate during the three growing years.

Culinary preparation of beetroot (Beta vulgaris L.): the impact on sensory quality and appropriateness.

Background: Beetroot is a diverse vegetable available in different shapes and colours. The objectives of this study were to evaluate sensory qualities, and sugar and dry matter content of five beetroot varieties in relationship to the appropriateness for raw, boiled and pan-fried preparation.

Results: Sensory evaluation by descriptive sensory analysis and consumer tests showed clear distinctions between red varieties Taunus, Rocket and Pablo, and the pink-white striped Chioggia and yellow Burpee's Golden in raw preparations.

Impact of mixtures of different fresh-cut fruits on respiration and ethylene production rates.

Unlabelled: Packaging and storage of fresh-cut fruits and vegetables are a challenging task, since fresh produce continue to respire and senesce after harvest and processing accelerates the physiological processes. The response on respiration and ethylene production rates of fresh produce to changes in O2 and CO2 concentrations and temperature has been extensively studied for whole fruits but literature is limited on processed and mixed fresh-cut fruits. This study aimed to investigate the effects of mixing various proportions of fresh-cut fruits (melon chunks, apple slices, and pineapples cubes) on respiration and ethylene production rates and to develop predictive models for modified atmosphere packaging.

Mapping the variation of the carrot metabolome using 1H NMR spectroscopy and consensus PCA.

Genetic variation is the most influential factor for carrot (Daucus carota L.) composition. However, difference in metabolite content between carrot varieties has not been described by NMR, although primary metabolites are important for human health and sensory properties.

Enzymatic browning and after-cooking darkening of Jerusalem artichoke tubers (Helianthus tuberosus L.).

Jerusalem artichoke tubers (Helianthus tuberosus L.) undergo enzymatic browning when peeled or cut, and turn grey after boiling, due to after-cooking darkening reactions between iron and phenolic acids. In an attempt to reveal the components responsible for these discolouration reactions, sensory evaluation and instrumental colour measurements were related to contents of total phenolics, phenolic acids, organic acids and iron in three varieties of raw and boiled Jerusalem artichoke tubers harvested in the autumn and the spring.

Investigation of volatiles emitted from freshly cut onions (Allium cepa L.) by real time proton-transfer reaction-mass spectrometry (PTR-MS).

Volatile organic compounds (VOCs) in cut onions (Allium cepa L.) were continuously measured by PTR-MS during the first 120 min after cutting. The headspace composition changed rapidly due to the very reactive volatile sulfurous compounds emitted from onion tissue after cell disruption.

Sensory quality and appropriateness of raw and boiled Jerusalem artichoke tubers (Helianthus tuberosus L.).

Background: The aim of the present study was to investigate the sensory attributes, dry matter and sugar content of five varieties of Jerusalem artichoke tubers and their relation to the appropriateness of the tubers for raw and boiled preparation.

Results: Sensory evaluation of raw and boiled Jerusalem artichoke tubers was performed by a trained sensory panel and a semi-trained consumer panel of 49 participants, who also evaluated the appropriateness of the tubers for raw and boiled preparation. The appropriateness of raw Jerusalem artichoke tubers was related to Jerusalem artichoke flavour, green nut flavour, sweetness and colour intensity, whereas the appropriateness of boiled tubers was related to celeriac aroma, sweet aroma, sweetness and colour intensity.

The influence of the fungal pathogen Mycocentrospora acerina on the proteome and polyacetylenes and 6-methoxymellein in organic and conventionally cultivated carrots (Daucus carota) during post harvest storage.

Many carrots are discarded during post harvest cold storage due to development of fungal infections, caused by, e.g., Mycocentrospora acerina (liquorice rot).

Chromatographic determination of changes in pigments in spinach (Spinacia oleracea L.) during processing.

The content of individual chlorophyll and carotenoid pigments is determined in three spinach varieties (Lorelei, Springfield, and Ballet) after processing. Raw spinach and spinach that is steam-blanched for 3, 9, or 15 min is stored frozen at -24 degrees C for 6 months. In addition, spinach is air-dried at 75 degrees C, packed in atmospheric air or nitrogen, and stored at ambient temperature for 6 months.

Changes in volatile compounds of carrots (Daucus carota L.) during refrigerated and frozen storage.

Carrots (Daucus carota L.) of cv. Bolero and cv.

Comparison of methods used for pre-concentrating small volumes of organic volatile solutions.

Eight pre-concentration techniques were compared for their capacity to retain volatile and semi-volatile solutes during evaporation of solvent (dichloromethane). The 2-ml test-samples containing 0.2 ppm or 2 ppm (v/v) of volatile and semi-volatile solutes were concentrated to a final volume of 1 ml, 200 microl and 50 microl, respectively.