New acacia gums fractions: how their features affect the foamability of sparkling base wines?

Abstract

When sparkling wine is served, the first attribute perceived is foam1. Bentonite is usually added to wine in order to cause particle flocculation, but this procedure also leads to a drastic loss of foamability2. Acacia gums improve the foamability of some sparkling base wines treated with bentonite3. Acacia gums are already authorized as additives in wine production4. We studied how the addition of new fractions from Acacia gums affected the wines foamability. Our work deepens the relationship between wine foamability and gums fractions properties. Eight sparkling base wines were elaborated by the traditional white winemaking method. Three of them were elaborated in three different regions from Spain: Malaga using Moscatel grapes as well as Saragossa and Tarragona (TA), both using Macabeo grapes. The other five base wines were elaborated in the French region of Champagne using Chardonnay (4) and Pinot noir (1) grapes. They were treated with bentonite, stirred and filtered. Acacia senegal (Asen) and Acacia seyal (Asey) gums were fractionated by Ion Exchange Chromatography giving two high (F1sen and F1sey) and two low (F2sen and F2sey) molar mass fractions. Fractions and sparkling base wines were deeply characterized. Four Acacia gums fractions were separately added to wines (300 mg·L-1), resulting in “supplemented CO-wines”. Based on shaking test, wine was vigorously hand-shaken in closed tubes. The foam height at 5 and every 10 seconds during 90 seconds was measured (all in triplicate). The maximum foam height was improved in 11 out of the 16 supplementations (69%) with F1 fractions, which were the fractions with high protein amount and high molar mass. F1sey and mainly F1sen showed a positive effect improving the foamability in Spanish wines. F1 fractions also increased foamability of French wines, but in a more inefficient and irregular pattern. Moreover, the differentials of foam height (ΔFH) between “supplemented CO-wines” and CO-wines enhanced significantly in all the studied wines at several moments after supplementations with F1 fractions. F2 fractions gave enhancing effect only sporadically. Adding F1sen and F1sey, the foam height showed positive Pearson correlations with, respectively, (i) polysaccharides rich in arabinose and galactose percentage and (ii) the number average molar mass of polysaccharides. But after F1 supplementations, the mannoproteins percentage in base wines affected negatively their foamability. The Proteins %, the hydrophobic score, the volumetric properties, the molar masses, the high molar mass ranges and the content of several amino acids of gums fractions affected positively the foamability in different wines, whereas it was negatively affected by the sugars %.Concluding, sparkling base wine foamabilities strongly depend on the wine and the gum fraction addition, but also on their relationship.

DOI:

Publication date: September 15, 2021

Issue: Macrowine 2021

Type: Article

Authors

Rafael Apolinar-Valiente, Thomas Salmo, Pascale Williams,  Michaël Nigen, Christian Sanchez, Thierry Doco,  Richard Marchal.

UMR-1208/IATE, Montpellier SupAgro, France.LOCA, Université de Reims, France. UMR-1083/SPO, INRAE-Montpellier, France. UMR-1208/IATE, Université Montpellier, France. UMR-1208/IATE, Université Montpellier, France. UMR-1083/SPO, INRAE-Montpellier, France. LVBE, Université de Haute-Alsace, Colmar, France.

Contact the author

Keywords

sparkling base wine; foam; acacia gums; ion exchange chromatography; macromolecules; sec-malls; biochemical properties; structural features

Citation

Related articles…

Grape berry size is a key factor in determining New Zealand Pinot noir wine composition

Making high quality but affordable Pinot noir (PN) wine is challenging in most terroirs and New Zealand’s (NZ) situation is no exception. To increase the probability of making highly typical PN wines producers choose to grow grapes in cool climates on lower fertility soils while adopting labour intensive practices. Stringent yield targets and higher input costs necessarily mean that PN wine cost is high, and profitability lower, in line-priced varietal wine ranges. To understand the reasons why higher yielding vines are perceived to produce wines of lower quality we have undertaken an extensive study of PN in NZ. Since 2018, we established a network of twelve trial sites in three NZ regions to find individual vines that produced acceptable commercial yields (above 2.5kg per vine) and wines of composition comparable to “Icon” labels. Approximately 20% of 660 grape lots (N = 135) were selected from within a narrow juice Total Soluble Solids (TSS) range and made into single vine wines under controlled conditions. Principal Component Analysis of the vine, berry, juice and wine parameters from three vintages found grape berry mass to be most effective clustering variable. As berry mass category decreased there was a systematic increase in the probability of higher berry red colour and total phenolics with a parallel increase in wine phenolics, changed aroma fraction and decreased juice amino acids. The influence of berry size on wine composition would appear stronger than the individual effects of vintage, region, vineyard or vine yield. Our observations support the hypothesis that it is possible to produce PN wines that fall within an “Icon” benchmark composition range at yields above 2.5kg per vine provided that the Leaf Area:Fruit Weight ratio is above 12cm2 per g, mean berry mass is below 1.2g and juice TSS is above 22°Brix.

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)

The modification of cultural practices in grapevine cv. Syrah, does it modify the characteristics of the musts?

The work shows the results of a year of experimentation (2020) in a Syrah variety vineyard in La Roda (Castilla-La Mancha, Spain). The trial approach was on a randomized block design with two factors: Irrigation (I) and Pruning (P).
Irrigation schedules were adjusted to apply amounts close to 1,500 m3/ha. With this provision, 2 different irrigation treatments were proposed: I1) Start of irrigation from pea-sized grape to post-harvest (providing at least 20 % of the total amount of irrigation water to be provided post-harvest); I2) Start of irrigation from pea-sized grape to harvest (usual irrigation practice in the study area). Pruning was proposed with two treatments, one at the end of January (P1), which is pruning on a conventional date; and P2) pruning carried out at the beginning of budding. In total, 4 repetitions were designed with 4 elementary plots, each one of them representing one of the proposed treatments (I1P1; I1P2; I2P1; I2P2). In total, 16 plots were worked on and each elementary plot consisted of 30 strains, distributed in 3 lines.
The productive response was evaluated with the yield results of the harvest harvested at 23 ºBrix. The qualitative response was measured in the musts through the indices of technological (acidity, pH and potassium) and phenolic maturity and aromatic compounds in free and glycosylated fractions. The treatments tested had, in general, an effect on the different variables analyzed.

Effects of organic mulches on the soil environment and yield of grapevine

Farming management practices aiming at conserving soil moisture have been developed in arid and semiarid-areas facing water scarcity problems. Organic mulching is an effective method to manipulate the crop-growing microclimate increasing crop yield by controlling soil temperature, and retaining soil moisture by reducing soil evaporation. In this sense, the effectiveness of different organic mulching materials (straw mulch and grapevine pruning debris) applied within the row of a vineyard was evaluated on the soil and on the vine in a Tempranillo vineyard located in La Rioja (Spain). Organic mulches were compared with a traditional bare soil management technique (based on the use of herbicides to avoid weed incidence). Mulching coverages favourably influenced the soil water retention throughout all the grapevine vegetative cycle. However, the soil-moisture variation was not the same under different mulching materials, being the straw mulch (SM) the one that retained more water in comparison with grapevine pruning debris (GPD) based-cover. The changes of soil moisture in the upper surface layer (0–10 cm) were highly dynamic, probably due to water vapour fluxes across the soil-atmospheric interface. However, both, SM and GPD reduced these fluctuations as compared with bare soils. A similar trend occurred with soil temperature. Both organic mulches altered soil temperature in comparison with bare soil by reducing soil temperature in summer and raising it in winter. Moreover, the same buffering effect for the temperature on the covered soil also remains in the deeper layers. To conclude, we could see that organic mulching had a positive impact on soil-moisture storage and soil temperature and the extent of this effect depends on the type of mulching materials. These changes led to higher rates of photosynthesis and stomatal conductivity compared to bare soils, also favouring crop growth and grape yields.

1H-NMR-based Metabolomics to assess the impact of soil type on the chemical composition of Mediterranean red wines

The aim of this study was to evaluate the effects of different soil types on the chemical composition of Mediterranean red wines, through untargeted and targeted 1H-NMR metabolomics. One milliliter of raw wine was analyzed by means of a Bruker Avance II 400 spectrometer operating at 400.15 MHz. The spectra were recorded by applying the NOESYGPPS1D pulse sequency, to achieve water and ethanol signals suppression. No modification of the pH was performed to avoid any chemical alteration of the matrix. The generation of input variables for untargeted analysis was done via bucketing the spectra. The resulting dataset was preprocessed prior to perform unsupervised PCA, by means of MetaboAnalyst web-based tool suite. The identification of compounds for the targeted analysis was performed by comparison to pure compounds spectra by means of SMA plug-in of MNova 14.2.3 software. The dataset containing the concentrations (%) of identified compounds was subjected to one-way analysis of variance (ANOVA) to highlight significant differences among the wines. The untargeted analysis, carried out through the PCA, revealed a clear differentiation among the wines. The fragments of the spectra contributing mostly to the separation were attributed to flavonoids, aroma compounds and amino acids. The targeted analysis leaded to the identification of 68 compounds, whose concentrations were significant different among the wines. The results were related to soils physical-chemical analysis and showed that: 1) high concentrations of flavan-3-ols and flavonols are correlated with high clay content in soils; 2) high concentrations of anthocyanins, amino acids, and aroma compounds are correlated with neutral and moderately alkaline soil pH; 3) low concentrations of flavonoids and aroma compounds are correlated with high soil organic matter content and acidic pH. The 1H-NMR metabolomic analysis proved to be an excellent tool to discriminate between wines originating from grapes grown on different soil types and revealed that soils in the Mediterranean area exert a strong impact on the chemical composition of the wines.