WINETECH Technical Yearbook 2020

Initially, no oxidation-related compounds were detected in the wine, however, after 12 and 18 months’ storage, an increase in the oxidation compounds phenylacetaldehyde (honey and floral-like aroma), methional (potato-skin aroma) and sotolon (curry nuances), was observed. For all the compounds measured, a significant increase was seen for both PETmono packaged wines. For the other packaging options, variable results were obtained. SENSORY ANALYSIS Judges were asked to score wines according to their “Sauvignon character” and “oxidative evolution” after six, 12 and 18 months. The wines bottled in glass, scored the highest for “Sauvignon character” during all the evaluations. Of the alternative packaging, PETmulti (750) showed the most promising result. The judges also reported an increase in “oxidative evolution” over time with the highest scores given to PET and BIB containers, again with PETmulti (750) showing most promising results out of all the alternative packaging options tested. CONCLUSIONS From the results reported in these studies, the future of alternative packaging for storage of wine is looking bleak. However, ongoing technological advancements

main factor that would cause a decline in wine quality. This is especially important for Sauvignon blanc as the varietal aroma is often dependant on oxidation sensitive aroma compounds, such as the volatile thiols. A study titled “The influence of packaging on wine conservation” (Ghidossi et al ., 2012), investigated the evolution of a Sauvignon blanc wine packaged in the dif- ferent containers over an 18 month period. The evaluation was done by measuring the dissolved gasses, certain wine constituents, as well as analysing the sensorial properties of the wine. REFERENCES Gerber, B. PET wine bottles: Plastic is fantastic. 2010. http://www.conca.co.za/ index.php?option=com_content&view=ar- t icle&id=159:pet-wine-bott les-plas- t ic- is- fantast ic&cat id=37:winemak- er&Itemid=63. Van Bree, I., De Meulenaer, B., Samapun- do, S., Vermeulen, A., Ragaert, P., Maes, K.C., De Baets, B. & Devlieghere, F., 2010. Predicting the headspace oxygen level due to oxygen permeation across multilayer polymer packaging materials: A practi- cal software simulation tool. Innovative Food Science and Emerging Technologies 11(3), 511-519. https://doi.org/10.1016/j. ifset.2010.01.007.

Winder, B., Ridgway, K., Nelson, A. & Bald- win, J., 2002. Food and drink packaging: Who is complaining and who should be complaining. Applied Ergonomics 33(5), 433-438. https://doi.org/10.1016/S0003- 6870(02)00026-1. Ghidossi, R., Poupot, C., Thibon, C., Pons, A., Darriet, L., Riquier, G., De Revel, G. & Mietton Peuchot, M., 2012. The influence of packaging on wine conservation. Food Control 23, 302-311. Besseas, E., 2014. Zoom sur la qualité des vins du val de Loire commercialisés en BIB ® , pp. 7-10. Hopfer, H., Ebeler, S.E. & Heymann, H., 2012. The combined effects of storage temperature and packaging type on the sensory and chemical properties of Chardonnay. Journal of Agricultural and Food Chemistry 60(43), 10743-10754. https://doi.org/10.1021/jf302910f. Revi, M., Badeka, A., Kontakos, S. & Kon- tominas, M.G., 2014. Effect of packaging material on enological parameters and volatile compounds of dry white wine. Food Chemistry 152, 331-339. https:// doi.org/10.1016/j.foodchem.2013.11.136.

could lead to packaging with less oxygen permeability. Other packaging options, such as aluminium cans, cartons and steel kegs (for wine on tap), also show potential and deserve further investigations. It is evident that for wines that will be consumed relatively quickly after bottling (which is often the case for Sauvignon blanc), alternative packaging is still a viable option, especially if the wines are stored at a low temperature. The most suitable choice of packaging depends on the expected shelf life of the product and on the type of distribution and marketing planned. SUMMARY Of course, when considering alternatives to glass, various factors need to be taken into account, such as processing constraints, the cost of the material and the target consumer acceptance and expectations (Winder et al ., 2002). The challenge is to find an alternative which is more environmentally friendly and less expensive, all the while maintaining the chemical and sensory composition and quality of the wine. Assuming the packaging itself does not alter the wine by removing wine aroma (absorption) or adding unnatural com- pounds, oxygen permeability would be the

For more information, contact Dr. Carien Coetzee at carien@basicwine.co.za.

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