The first job of any packaging is to protect what’s inside. In the case of a wine bottle, that extends from the time it’s filled and capped until long after the consumer carries it from the store. It’s unquestionably the more important of the functions. If the bottle doesn’t protect the wine inside, nothing else matters.
UV Protection and the “Light-Struck” Risk
Exposure to light causes wine to go bad, and not just from an overheated storage perspective. Delicate whites and rosés are the most vulnerable to light strike, a photochemical reaction caused by UV and visible sunlight rays. The phenolic structure of these wines reacts relatively quickly, producing sulfur compounds that lead to the tell-tale off-aromas of skunk or cat urine.
Amber glass blocks nearly 90% of harmful UV rays, while standard flint glass may allow up to 90% of that same light to pass through, accelerating the breakdown of riboflavin and tartrates (Journal of Food Science and Agriculture). Antique green and dead leaf green fall somewhere between those extremes. That’s why they’ve been the default for many white and sparkling wines for decades; high-end champagne houses with thousands of grand cru bottles sitting for decades in deep underground reserves wouldn’t have it any other way.
Visibility Versus Vulnerability
There is a valid case for letting the wine speak for itself. Clear wine bottles are advantageous when used as a true marketing device. For instance, emerging brands or under-the-radar regions where the wine’s story isn’t widely known can benefit from the cache and intrigue that a classic bottle with a deep punt and generous, old-style raised print applied label. Your wine has to stand out, and a classic bottle can help you rise above the noise of a crowded shelf (real or virtual) and get customers to pick up your bottle, turn it around, and read it.
Bottle Shape and Brand Positioning
The two dominant silhouettes, the high-shouldered Bordeaux and the sloped Burgundy, automatically communicate varietal information to consumers. A Cabernet Sauvignon in a Burgundy bottle makes a varietal mismatch that buyers can’t quite put their finger on, but will nevertheless subconsciously notice. The same applies to a Pinot in a Bordeaux bottle.
More practically than varietal convention, the punt at the bottom of the bottle matters far more than most people think it does. The punt is necessary for the added stability that high-speed automated filling lines and high-pressure carbonation require. It’s also what makes the bottle square, which in turn affects how many bottles can be packed together in a case and how many cases can be packed together in a shipment. A punt that is produced in the mold purely as a decorative feature is a cool design flourish, but could be less effective if it doesn’t also provide structural benefits and if it throws off your filling line tolerances.
The physical design of the bottle also plays a role in label adhesion. Different cold-end glass treatments adhere differently to pressure-sensitive labels compared to wet-glue applications. If you’re not doing proper adhesion testing on the actual bottle first, you’re in for a hell of a surprise when those bottles start falling off the back of the shelf.
Weight, Logistics, and Total Cost
Using more cullet can significantly reduce the raw materials cost and CO2 emissions associated with producing your glass, but you might also find that it changes the appearance, and perhaps even the performance, of the bottle in unexpected ways. It’s critical to weigh all the elements of a material change before you start producing new products. Sometimes, the higher price for extra shipping weight is worth it when you factor in the perceived quality difference by your customers.
Neck Finish and Closure Compatibility
The glass supplier, repackager or decorator, the bottle design itself, the label, and the closure: you can’t make the best decision on your bottle until you know your options on each of these interconnected subjects.
For example, lighter bottles: a noble goal for all the right reasons. They require less energy to produce, less carbon to ship, and less shelf strength to bear. The consequences of incorrect shelf and shipping weights can be heavy financial penalties for your profitability. If you are importing goods, there’s a risk of duties being improper based on declared weight and quantity.
For the U.S. market, the shipping weight and shelf weight are the numbers declared on the case and the pallet, respectively, and if those are incorrect the TTB can and will fine you financially per bottle on subsequent shipments. A lightweight bottle also might be less expensive to buy, and more expensive to fill. Lighter bottles make the strongest cases for cultural shifts in material decisions and cost accounting.
