Carrageenans as heat stabilisers of white wine

Abstract

Background and Aims Carrageenan addition has been previously shown to remove proteins from wine and to heat stabilise wines, however, many types of carrageenans are now available with potentially different protein‐adsorbing properties. This study investigated a range of commercially available carrageenans added at several stages of winemaking for efficacy of protein removal, heat stability and impact on wine sensory properties. Methods and Results In preliminary screening trials, 11 types of carrageenan were added to a Chardonnay wine and the heat stability of the wine measured with a heat test. Three of the carrageenans successfully heat‐stabilised the wine and were included in large‐scale winemaking trials: sodium‐rich kappa (kN), potassium‐rich kappa (kK) and kappa/iota (90:10, ki) carrageenan. Each carrageenan was added at three stages of winemaking, to juice, during fermentation and to wine. All carrageenans produced heat‐stable wine regardless of time of addition. Addition of kN during fermentation also improved wine recovery compared to bentonite addition, the positive Control, although sodium concentration also significantly increased in the wine. Addition of kK‐carrageenan to either wine or clarified juice was the most effective treatment for producing heat‐stable wine with minimal impact on the sensory profile, wine lees, turbidity and concentration of metal ions compared to that of untreated Control wines. Conclusions Kappa‐ and kappa‐/iota‐carrageenans can be effective at heat stabilising white wines without negative impact on sensory properties, although the filterability and concentration of metal ions of the wines can vary with carrageenan structure and time of addition. Significance of the Study Kappa‐carrageenan, a renewable fining agent, is effective in heat stabilising wines and maybe become a useful alternative to bentonite.

White Wine Protein Instability: Mechanism, Quality Control and Technological Alternatives for Wine Stabilisation—An Overview

“…However, bentonite fining treatment presents some disadvantages, resulting in a loss of economic value [7]. Decreasing bentonite applications and/or finding alternative technologies or products, such as the use of yeast mannoproteins [19,38,140], the use of regenerable adsorbents [29][30][31][32][33][34], carrageenan, chitin, chitosan, ultrafiltration and flash pasteurisation or the use of proteolytic enzymes [5,6,[23][24][25][26][27][28][35][36][37], are of utmost interest for the wine industry.…”

“…Bayly and Berg [66] conclude that the elimination of the different wine protein fractions by bentonite addition did not happen in equal proportion. Bentonite first eliminates proteins with high pI (5.8-8.0) and intermediate MW (32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45). However, by 2D-GE, Hsu et al [23], observed that, to stabilise wine, it is essential to eliminate proteins with lower pI (4.1-5.8) and lower MW (12.6 and 20-30 kDa), including glycoproteins, which represent a major fraction of proteins.…”

“…Agar, carrageenan and alginic acid, polysaccharides extracted from seaweeds, due to their negative charge at low pH, can electrostatically flocculate and precipitate positively charged proteins and be a potential alternative for wine protein stabilisation [5,37,192,193].…”

“…Marangon et al [192], also showed that carrageenan has no deleterious sensory impacts compared to bentonite-treated wines. More recently, Ratnayake et al [37] studied commercially available carrageenans at different winemaking stages-in grape juice, during fermentation and in wine-to know the efficacy of protein removal and impact on the wine sensory properties. Three different Purified carrageenan, dried carrageenophytes, purified alginic acid, and dried alginophytes showed a two-fold higher ability to flocculate and precipitate proteins compared to agar and agarophytes [193].…”

“…However, bentonite fining can affect wine quality, for example, by removal of colour and aroma compounds [7,21] and, therefore, can affect wine sensory characteristics [22]. Therefore, alternative techniques to bentonite fining for this goal have been studied, such as ultrafiltration [6,23,24], addition of proteolytic enzymes [25,26], flash pasteurisation [27,28], other adsorbents (silica gel, hydroxyapatite and alumina) [29], zirconium oxide [30][31][32], natural zeolites [33,34], chitin and chitosan [35,36], carrageenan [5,37] and the use of some mannoproteins [19,38].…”