The Chemical, Microbiological and Volatile Composition of Kefir-like Beverages Produced from Red Table Grape Juice in Repeated 24-h Fed-Batch Subcultures

 Foods 2022, 11(19), 3117

The aim of this work was to study the production of kefir-like beverages via the fed-batch fermentation of red table grape juice at initial pHs of 3.99 (fermentation A) and 5.99 (fermentation B) with kefir grains during 4 repeated 24-h fed-batch subcultures. All kefir-like beverages (KLB) were characterized by low alcoholic grade (≤3.6%, v/v) and lactic and acetic acid concentrations. The beverages obtained from fermentation B had lower concentrations of sugars and higher microbial counts than the KLB obtained in fermentation A. Additionally, the KLB samples from fermentation B were the most aromatic and had the highest contents of alcohols, esters, aldehydes and organic acids, in contrast with the nonfermented juice and KLB from fermentation A. These results indicate the possibility of obtaining red table grape KLB with their own distinctive aromatic characteristics and high content in probiotic viable cells, contributing to the valorization of this fruit.

Volatile Flavor Compounds of Pugionium cornutum (L.) Gaertn. Before and After Different Dehydration Treatments

 Front. Nutr., 2022

Pugionium cornutum (L.) Gaertn (also Pugionium) is a special Mongolian vegetable, belonging to the Cruciferous family, growing in arid and semi-arid areas of northern China, with a unique flavor and potential health benefits. This article aims to describe the profile of volatile flavor compounds in fresh and different dehydrated samples, establish the fingerprint, and identify the characteristic compounds. The fresh Pugionium sample and 3 kinds of dehydrated samples were analyzed. Headspace/gas chromatography-ion migration spectrometry (HS/GC-IMS) and solid-phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) were used for identification and relative quantification. HS/GC-IMS identified 78 compounds, whereas SPME/GC-MS identified 53 compounds. Principal component analysis (PCA), clustering analysis, and partial least squares discriminant analysis (PLS-DA) were used as appropriate to investigate variations in volatile compounds among Pugionium samples and identify distinctive compounds. The first two principal components described 76.5% and 69.5% of the variance of the data from HS/GC-IMS and SPME/GC-MS, respectively. By clustering analysis, 4 kinds of Pugionium samples could be classified into four independent groups. The similarity between fresh Pugionium and natural dehydration Pugionium was higher than the other two dehydrated samples, indicating that natural dehydration can better preserve the flavor of Pugionium. Most aldehydes and alcohols increased following different dehydration procedures, whereas esters decreased, and the dehydrated Pugionium samples have more harmonious and less pungent aroma than the fresh Pugionium. PLS-DA model analysis revealed that the marker compounds (VIP scores > 1) discriminating the flavor of the four samples for HS/GC-IMS and SPME/GC-MS were 24 and 15 compounds, respectively, such as 2-phenylethyl isothiocyanate, 1-butene-4-isothiocyanate and other isothiocyanates, 2-propanone, nonanal, gamma-butyrolactone, 2,3-butanediol, 3-methyl-2-butenenitrile, and pentanal. Analysis of volatile compounds might be useful for monitoring the quality of Pugionium and guiding the cooking methods and processing technologies. More study is required to discover if the various volatile flavor compounds have biological or physiological impacts on nutrition.

Characterization of virgin olive oils produced with autochthonous Galician varieties

Food Chemistry 212 ( 2016) 162–171

http://dx.doi.org/10.1016/j.foodchem.2016.05.135

The interest of Galician oil producers (NW Spain) in recovering the ancient autochthonous olive varieties Brava and Mansa has increased substantially in recent years. Virgin olive oils produced by co-crushing both varieties in two different proportions, reflecting the usual and most common practice adopted in this region, have gradually emerged for the production of virgin olive oils. Herein, the sensory and chemical characteristics of such oils were characterized by quality and genuineness-related parameters. The results of chemical analysis are discussed in terms of their effective contribution to the sensory profile, which suggests useful recommendations for olive oil producers to improve the quality of oils. Antioxidant compounds, together with aromas and coloured pigments were determined, and their contribution in determining the functional value and the sensory properties of oils was investigated. In general, given the high levels of phenolic compounds (ranging between 254 and 375 mg/kg oil), tocopherols (about 165 mg/kg oil) and carotenoids (10–12 mg/kg oil); these are oils with long stability, especially under dark storage conditions, because stability is reinforced with the contribution of chlorophylls (15–22 mg/kg oil). A major content of phenolic compounds, as well as a predominance of trans-2-hexen-1-al within odor-active compounds (from 897 to 1645 μg/kg oil), responsible for bitter sensory notes. This characterization allows to developing new antioxidant-rich and flavour-rich VOOs, when co-crushing with a higher proportion of Brava olives, satisfying the consumers’ demand in having access to more healthy dishes and peculiar sensory attributes.

Production and characterization of a novel distilled alcoholic beverage produced from blueberry (Vaccinium corymbosum L.)

Fruits, 2016, vol. 71(4), 215-220

http://dx.doi.org/10.1051/fruits/2016013

The cultivation of underutilized berries and the process production of high-value-added products, such as fruit-based spirits, could have a beneficial effect on the economy of disadvantaged rural mountain areas of Spain. However, production of a distilled alcoholic beverage from the blueberry has not been reported before. The pulp of blueberries var. Bluecrop was fermented with Saccharomyces cerevisiae IFI83, distilled by using a steam drag distillation system and the volatile compounds were determined by gas chromatography. In the distillate obtained, the mean concentrations of ethanol (45.3 mL 100 mL-1 distillate), volatile substances (317.1 g hL-1 absolute alcohol) and methanol (261.0 g hL-1 absolute alcohol) were in accordance with the specifications that the European Council (Regulation 110/2008) fixed for these compounds. In addition, the ratios [3-methyl-1-butanol/2-methyl-1-propanol] and [2-methyl-1-propanol/1-propanol] were 2.60 and 1.34, respectively, indicating that the distilled alcoholic beverage has a good organoleptic quality. The results suggest that blueberry can be successfully used for the production of a novel spirit with a good sensory quality that is safe for the consumers.

Production et caractérisation d’une nouvelle boisson alcoolisée distillée produite à partir de grande myrtille (Vaccinium corymbosum L.)

Fruits, 2016, vol. 71(4), 215-220

http://dx.doi.org/10.1051/fruits/2016013

La culture d’espèces de baies sous-utilisées et leur transformation en produits à haute valeur ajoutée, tels que les spiritueux à base de fruits, pourraient avoir un effet bénéfique sur l’économie des régions rurales et défavorisées des montagnes d’Espagne. La production d’une boisson alcoolisée distillée à partir de grandes myrtilles ou bleuets n’a pourtant jamais été signalée auparavant. La pâte de bleuet var. Bluecrop fermentée avec Saccharomyces cerevisiae IFI83, a été distillée en utilisant un système de distillation par train de vapeur d’eau; les composés volatils ont été déterminés par chromatographie en phase gazeuse. Dans le distillat obtenu, les concentrations moyennes d’éthanol (45,3 mL 100 mL-1 distillat), de substances volatiles (317,1 g hL-1 alcool absolu, aa) et de méthanol (261,0 g hL-1 aa) étaient conformes aux spécifications que le Conseil européen (règlement 110/2008) fixe pour ces composés. De plus, les rapports [3-méthyl-1-butanol/2-méthyl-1-propanol] et [2-méthyl-1-propanol/1-propanol] ont été de 2,60 et 1,34, respectivement, indiquant que la boisson alcoolisée distillée a une bonne qualité organoleptique. Les résultats suggèrent que la grande myrtille peut être utilisée avec succès pour la production d’un nouveau spiritueux de bonne qualité organoleptique et sanitaire pour les consommateurs.

Terpenoid trans-caryophyllene inhibits weed germination and induces plant water status alteration and oxidative damage in adult Arabidopsis

Plant Biology

DOI: 10.1111/plb.12471

trans-Caryophyllene (TC) is a sesquiterpene commonly found as volatile component in many different aromatic plants. Although the phytotoxic effects of trans-caryophyllene on seedling growth are relatively explored, not many information is available regarding the phytotoxicity of this sesquiterpenes on weed germination and on adult plants. The phytotoxic potential of TC was assayed in vitro on weed germination and seedling growth to validate its phytotoxic potential on weed species. Moreover, it was assayed on the metabolism of Arabidopsis thaliana adult plants, through two different application ways, spraying and watering, in order to establish the primary affected organ and to deal with the unknown mobility of the compound. The results clearly indicated that TC inhibited both seed germination and root growth, as demonstrated by comparison of the ED50 values. Moreover, although trans-caryophyllene-sprayed adult Arabidopsis plants did not show any effect, trans-caryophyllene-watered plants became strongly affected. The results suggested that root uptake was a key step for the effectiveness of this natural compound and its phytotoxicity on adult plants was mainly due to the alteration of plant water status accompanied by oxidative damage.

Evaluation of the effect of fenhexamid and mepanipyrim in the volatile composition of Tempranillo and Graciano wines

Food Research International

Volume 71, May 2015, Pages 108–117

doi:10.1016/j.foodres.2015.02.025

Grapes from Vitis vinifera var. Tempranillo and Graciano of La Rioja (North Central Spain) were vinified after addition of two fungicides (mepanipyrim and fenhexamid) at concentrations corresponding to their MRLs. These fungicides are commonly used in the vine growing to control botrytis disease. The fungicide effect throughout winemaking on the volatile composition and aroma profile of the final wines was evaluated, together with the level of fungicide residues in the final wines that were found to be safe for consumers. Concentrations of C13-norisoprenoids in Graciano wines obtained after the addition of both active substances showed the greatest variations with respect to control wine; whereas the concentration of volatile compounds in Tempranillo wines were seemingly unaffected by the presence of fungicide residues. On the other hand, the aroma profile of monovarietal red wines was evaluated by using odorant series which included volatile compounds with similar odour descriptors. In this sense, supplementation with the antifungals seemed to increase the OAV for the ripe fruit series with respect to the control wines in Graciano wines.

Wine Aroma Compounds in Grapes: A Critical Review

Critical Reviews in Food Science and Nutrition, 2015, 55(2), 202-218

Volatile organic compounds are vital to wine quality, determining their aroma and varietal characteristics. Which are present, and in what quantity, depends on the cultivar, the situation and soil of the vineyard, weather, cultivation methods, and wine-making practices. Here, we review the literature on the development of wine aroma compounds in grapes, and how it is affected by the above-named factors. Increasing understanding of these processes at the molecular level will aid vine growers in the optimal selection of harvest dates and other decisions favoring the consistent production of balanced, flavorful berries. 

Characterisation of extra virgin olive oils from Galician autochthonous varieties and their co-crushings with Arbequina and Picual cv.

Food Chemistry (2015) 176, 493-503

The current trend of the olive oil market is the production of high quality extra from traditional minor olive varieties with peculiar and differentiated characteristics (especially with respect to the aromatic and phenolic composition). In this way, the interest of Galician oil producers (NW Spain) in recovering old autochthonous Local olive fruits has increased substantially in recent years. In order to investigate the potential of the Local olives by either producing high quality monovarietal oils or mixing with the most widespread olives in Galicia (Arbequina and Picual cv.), quality indices, and fatty acid composition as well as volatile and phenolic profiles were determined and compared. All EVOOs studied in this work can be considered as "extra virgin olive oil" due to quality indices fell within the ranges established in legislation. Picual and Local olive oils as well as those resulting from their co-crushing reach values which are required by EU legislation to add the specific health claim on the oil label. Co-crushing Picual:Local (80:20) provided a significant enhancement of grass and apple nuances and a decrease of banana notes with respect to Picual oils. The co-crushing process improved sensory and health properties of Picual extra virgin olive oils. The effect of co-crushing on phenolics, ester volatiles and banana nuances cannot be easily modulated, contrary to quality indices and fatty acid composition, both changing linearly in strict correlation with the fruit mass ratio.