 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Effect of application of kaolin and pinolene on grape berry cell death, berry shrinkage, and ethanol accumulation

Effect of application of kaolin and pinolene on grape berry cell death, berry shrinkage, and ethanol accumulation

Abstract

AIM: Cell death in Vitis vinifera L. berries late in ripening and berry shrinkage (loss of mass) can decrease yield and reduce grape quality in cultivars such as Cabernet Sauvignon, Merlot, and especially Shiraz. Techniques to ameliorate effects of cell death and berry shrinkage are limited. Pinolene and kaolin are two types of film-forming antitranspirants applied to plants to reduce water loss. If these antitranspirants create a water impermeable coating, they may also restrict gas exchange, exacerbating hypoxia associated with cell death in grape berries. This study aimed to identify the effects on berry physiology during ripening of kaolin and pinolene coatings on Shiraz and Grenache bunches.

METHODS: Kaolin (6% w/w), pinolene (1% w/w) and water (control) were sprayed on Shiraz and Grenache bunches (2019-2020, Waite campus University of Adelaide) during ripening every 7 to 15 days. Change in berry mass, cell vitality, internal oxygen concentration, ethanol accumulation and bunch and canopy temperature were recorded.

RESULTS: Grenache berries had almost no shrinkage and no cell death during development contrasting to continuous decline in berry mass and cell vitality in Shiraz berries from 85 days after anthesis. Kaolin had no effects on berry properties. Pinolene reduced loss of berry mass in Shiraz and slightly increased berry mass in Grenache, leading to lower sugar concentrations in both cultivars. There was no effect of pinolene on berry oxygen concentration or cell vitality since both declined similarly to controls. There was an exponential increase in berry ethanol concentration with increasing mean daily temperature. Berry ethanol concentration for Grenache was much lower than for Shiraz under similar temperature conditions. There was no effect of treatments on berry ethanol concentrations.

CONCLUSIONS

Pinolene decreased berry shrinkage and prevented high sugar concentration presumably by reducing transpiration without impacting sugar content. It was surprising that this compound could decrease water loss without apparently affecting internal oxygen concentration in the berry. Ethanol accumulation during berry ripening could be a causative factor of cell death or is closely associated with it. Temperature may decrease berry vitality by accelerating respiration which leads to anoxia and high ethanol production.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Lishi Cai

School of Agriculture, Food and Wine, The University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia,Apriadi Situmorang School of Agriculture, Food and Wine, The University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia Steve Tyerman School of Agriculture, Food and Wine, The University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia

Contact the author

Keywords

Citation

Climatic requirements for optimal physiological processes: a factor in viticultural zoning

Les profils climatiques appropriés pour une activité photosynthétique optimale de la vigne sont déterminés dans différentes régions d’Afrique du Sud et localités à l’intérieur d’une région particulière.

Oxygen consumption by diferent oenological tanins in a model wine solution

INTRODUCTION: Oenological tannins are widely used in winemaking to improve some characteristics of wines [1] being the antioxidant properties probably one of the main reasons [2]. However, commercial tannins have different botanical sources and chemical composition [3] which probably determines different antioxidant potential. There are some few references about the antioxidant properties of commercial tannins [4] but none of them have really measured the direct oxygen consumption by them. The aim of this work was to measure the kinetics of oxygen consumption by different commercial tannins in order to determine their real capacities to protect wine against oxygen. MATERIAL AND METHODS: 4 different commercial tannins were used: T1: condensed tannin from grape seeds, T2: gallotannin from chinese gallnuts, T3: ellagitannin from oak and T4: tannin from quebracho containing condensed tannins and ellagitannins.

Il Soave: esempio di cultura e di scienza

L’evoluzione del settore viti-enologico, supportato dalla ricerca ci propone sempre più frequentemente vini unici e inconfondibili. Il merito di ciò è da ricercare nel rapporto vitigno-territorio e dalla

Interest and impact of PVP/PVI (Polyvinylpyrrolidone/ Polyvinylimidazole) on winemaking and final quality of wines

Céline Sparrow a, Christophe Morge a, a SOFRALAB SAS, 79, av. A.A. Thévenet – CS 11031 – 51530 Magenta, France Consumers’ health and security force authorities to limit, in wine as in others food industry products, the concentration in « dangerous » molecules. Therefore the legal limit in heavy metals keeps on decreasing. As per proof EU regulation just decrease the stain concentration in wine from 0,2 to 0,15 mg/l. Certain changes , such as sodium arsenite treatment in vines, disappearance of brass in wineries to the benefit of stainless steel, limit even more the concentration of heavy metals in wines. But the use of copper derivates in vines treatments is difficult to replace. In the case of wine and its elaboration, the problem is even more complex. Indeed, regulation forces the wine producers to control the concentration of certain heavy metals in final wines.

Emosensory profile and chemical characterization of wine vinegar from the Douro and Rioja demarcated regions

Wine vinegars have a tangy flavor and are versatile in cooking. They’ve been used since the neolithic period and are now used as microbial inhibitors and acidifiers. They’re low in calories, have antioxidants, and have a long shelf life, but quality may decrease after opening. The objective of this study focuses on the physical-chemical, sensory, and emotional characterization of wine vinegar samples from the douro demarcated region and la rioja. In total, 22 samples of wine vinegar were analyzed at the time of opening.