‘‘Sound is a key part of the process of flavour perception,’’ says Russell Keast.
Exposed walls and ceiling, concrete floor, hard timber furnishing and thumping music – a modern restaurant can be a noisy place.
But is our yearning for industrial chic making food taste worse in restaurants where we can’t hear each other speak? Academics, restaurateurs and sound engineers all think so.
Three studies published in scientific journals in the United States and Britain found conclusive evidence that background noise has a “significant” effect on how food tastes.
All three studies found noise levels above 80 decibels made us less able to taste sweetness, while two studies found both sweetness and saltiness were diminished.
In a 2011 study published in British journal Food Quality and Preference, about 50 participants tasted potato chips, cheese, biscuits and pancakes. Tasters ate the food in one setting where background noise was set to 50 decibels – the same noise level as a living room conversation – and another where noise was set to 80 decibels, about the same as being in a plane cabin.
Participants rated the salty foods (chips and cheese) as significantly less salty and sweet foods (biscuits and pancakes) as tasting less sweet under conditions of loud background noise.
The findings align with those made by an Australian academic nicknamed the “Taste Professor”, who also found elevated noise levels reduced our ability to taste sweetness and saltiness, and increased bitterness.
“Sound is a key part of the process of flavour perception,” said Russell Keast, an associate professor of food and sensory science at Deakin University.
“Loud noise enhanced the negative [bitterness] and reduced the positive [sweet and savoury] … that is very clear from lab testing.”
The phenomenon, according to Keast and the published studies, could be down to a “crowding-out” effect, where the brain is not able to focus on flavours as it processes loud noise.
Too much noise also confuses our brains when eating crisp or crunchy foods by drowning out the sound associated with eating those foods.
“If we’re eating a potato chip, it should be crisp. The flavour is almost irrelevant – texture is more important to the enjoyment, and a key part of texture is the sound associated with crispness,” Keast said.
“When it’s noisy, the sound that emanates when we fracture the chip is reduced. All of a sudden, the expectation in our brain for the sound associated with a crisp chip is reduced, and the chip hasn’t met our expectations.
Noise’s effect on food isn’t all one-way – it can amplify the flavour of umami, the so-called “fifth taste” found in glutamate-rich foods such as cooked meats, broths, shellfish and cheeses.
So, why are our restaurants so loud?
Sound engineers and restaurateurs say the trend towards hard-surfaced fitouts caused sound to bounce around dining rooms with nowhere to be absorbed.
Tony Eldred, who has advised top restaurants in Sydney and Melbourne for three decades, says minimalist fitouts – which originated in the 1990s and have grown in popularity ever since – allow restaurateurs to save on building costs.
“Almost all innovations in restaurants,” said Eldred, “come for economic reasons, not artistic ones.”
“If you acquire a building with exposed concrete walls and don’t have to do anything to them, and then don’t have to put a suspended ceiling in, you can save an awful lot of money.”
Much like laser tattoo removalists capitalising on an ink frenzy, the boom in industrial-style restaurant interiors has been a fillip for acoustic engineers.
Jacob McAllister, who manages SoundFix Acoustics, said establishing his business soon after 2010 was “the right time to get in”.
McAllister has been hired by dozens of Melbourne restaurants, who often pay thousands of dollars to have their dining rooms retro-fitted with sound-absorbing features.
Ben Wood – co-owner of a high-end South American restaurant group – was one who came knocking.
When Peruvian restaurant Pastuso opened in AC/DC Lane in 2014, the concrete, tile and timber fitout resulted in a decibel level hovering in the 90s, akin to standing at the back of a room where a band was playing, according to Wood.
Music was turned up so it could be heard over the noise, and by the end of a shift staff were hoarse from shouting in order to be heard by customers and other staff.
Less than a year after opening, management spent tens of thousands of dollars installing acoustic panelling, special sound-absorbing plaster, false ceilings and carpet.
The changes had a “significant” effect on the sound level, according to Wood.
Complaints from diners tumbled from several every night to only a few each year.
Wood says the high cost of acoustics and a narrow focus on achieving a specific “look” stopped restaurateurs from investing in acoustics when building a restaurant.
“Most of our restaurants are designed by architects, who have no idea about acoustics,” he says.
“Fit-outs cost millions of dollars these days, so corners are cut, and acoustic costs are often the first to go.”