Two stories caught my attention recently because they involve taste and mice, subject matters not often found together.

The first is a study that suggests that in addition to salt, sweet, sour, bitter and umami we may have a sixth taste—a taste for water. A team of scientists from the California Institute of Technology led by Yuki Oka were able to isolate taste receptor cells in mice that respond to water.

The most surprising part of the project” was that the well-known, acid-sensing, sour TRCs fired vigorously when exposed to water, Oka says…More research is needed to precisely determine how the acid-sensing taste buds respond to water, and what the mice experience when they do, Oka says. But he suspects that when water washes out saliva—a salty, acidic mucus—it changes the pH within the cells, making them more likely to fire.

The long-held assumption that we have only 5 basic tastes is increasingly on shaky ground.

The second story is entitled “Why Do Some Wines Taste of Mouse Cage?”

Yuk. Mouse cage? Who wants that in their wine? The story turns out to be a diatribe against the natural wine movement—winemakers who refuse to use sulfur dioxide in order to protect their wine from yeasts and bacteria that cause off flavors. The article by Simon Wolff claims:

The resulting wines span the entire gamut from sensational and pure to dirty and borderline undrinkable.

Well all wines span that gamut, natural or not. But the refusal to use sulfur has become a symbolic gesture signaling the belief that all hi-tech additives and processes are an affront to the purity of wine made to express the nature of grapes rather than the hand of the winemaker. The usual off flavors are the product of volatile acidity, Brettanomyces, or excessive oxidation, factors that when present in small amounts can actually increase the complexity and interest of a wine. But “mouse cage” is something else:

The mucky aftertaste generally known as ‘mousiness’ is a much more slippery pest. Poorly understood in the industry, virtually opaque to consumers, it has neither been conclusively researched nor openly acknowledged by some producers. Yet this unmistakeable taint – once recognised, never forgotten – seems to be on the increase, scurrying ever more rampantly around the cellars of a thousand radical vignerons….The taint manifests itself in a unique and troublesome fashion – the compounds are not volatile at the normal pH level of wines, and thus are virtually undetectable by smell. When infected wine mixes with the taster’s saliva, the pH is raised to a level where the 2-acetylpyridine is perceived retronasally – an aftertaste which is technically an aroma. This nasty surprise can sometimes take as long as 30 seconds to develop in the mouth, giving an entirely new meaning to wines with a ‘long finish’.

That all sounds unpleasant. But I taste a lot of wines every year, sometimes as many as 100 in a week, and I don’t recall any that reminded me of mouse cage. But maybe that’s just me.

Anecdotal evidence suggests there’s a very wide range of tolerance amongst wine professionals and consumers, from blissful ignorance to super sensitivity. An individual’s ability to detect mousy taint may well hinge on the pH level of their saliva – ergo possibly a genetic condition.

Most but not all of the wines I taste have been vinified using some SO2 so maybe I’m not sufficiently exposed to “mousy” wines. At any rate, we have a new wine flaw to be concerned with and I’ll be scrutinizing tasting menus for any hint of “mouse cage”.