Just a relatively quick post, as things are have been and are continuing to insist upon being busy – I’ve had a round of assessment for my PhD (my mid-candidature review), participated in a speaking competition about my PhD, done a talk about “seducing with neuroscience” (maybe I’ll post something about that at some stage – it’s not food-related but it is very interesting, and despite the evocative name it’s actually about how neuroscience information influences people’s judgments about the credibility of explanations), and now I’m madly analysing data to get an abstract submitted for a conference in November prior to leaving for a conference coming up in September (yep, it’s overseas-trip-time for me again, for the fourth time in 18 months – more on that later too, I guess).
SO! Another one to file away in the “how to influence people’s perception of food” category – can you influence people’s perception of food by manipulating something as simple as the weight of the dish it’s served in?
YES! It seems…
In a study by Piqueras-Fiszma and colleagues, participants were asked to rate 3 yoghurt samples in terms of flavour intensity, density, price expectation and liking. The yoghurt samples were served in three bowls that were all identical except for their weight: they were white ceramic bowls to which a hidden weight could be attached, so that the lightest bowl was 375g, the intermediate-weight bowl was 675g, and the heaviest bowl was 975g. Each bowl was used to serve a 150g sample of plain old Greek yoghurt (important information for study replication: it was purchased from Tesco!).
Participants had to hold the bowl in one hand while they sampled the yoghurt, and each bowl was taken away before the next one was given, so that there was never a chance to directly compare the weights.
Of course, it was the exact same yoghurt in each of the three samples that each participant tried – the only difference was the weight of the bowl the yoghurt was served in. But the participants didn’t know that. They probably assumed they were taste-testing different yoghurts.
Results showed that the heavier the bowl, the higher people rated the perceived density of the yoghurt when they sampled it, and the more money they expected to pay for it. Also, the heavier the bowl, the more participants liked the yoghurt. Perceived flavour intensity was not significantly affected by the weight of the bowls.
So everyone go out immediately and buy really heavy bowls and plates! Serve your things in heavy dishes all the time! Force your dinner guests to hold the crockery in their hands as they eat! Make people think your food is more fancy, more expensive, more lovely!
Or not. These results probably can’t be generalised too much – maybe you only get this effect for particular foods, and yoghurt just happens to be one of them. Maybe the effect changes depending on other properties of the food, e.g. maybe the volume of yoghurt is difficult to visually gauge because it’s just a big amorphous lump, so people’s perceptions are only influenced when the amount of food is difficult to get an idea of. Maybe putting something a bit more discrete, like an apple, into the different bowls would get a different result.
And it would be interesting to do a study investigating whether the weight of the vessel influences the amount of food eaten – maybe if the bowl is heavier, the food seems denser, and perhaps the brain is tricked into thinking the food is more calorific and so satiety occurs sooner. Who knows? I mean, there are many cues that the brain uses to determine satiety, so maybe it would be difficult to detect an effect of serving dish weight, but it is intriguing…
Anyway, it’s brownie time. Or blondie, as the case may be, I don’t know what defines one versus the other. Do blondies simply lack the predominance of cocoa or milk/dark chocolate in the batter? Anyway, the photos above are of some ridiculously delicious blondies (we’ll go with blondies for the name), featuring one of the greatest things known to humankind: peanut butter. They are peanut butter and waffle blondies (they have waffle crumbs throughout them) with dark chocolate chips. I recently made a variation of the recipe, photos of which are below: peanut butter, waffle and malt biscuit blondies with white chocolate chips and strawberries. I made those for a friend who recently endured an incredibly difficult experience (understatement of the century) and has just gotten out of hospital.
Recipe for peanut butter blondies (and variations thereof)…
Original recipe from Rachel Allen here.
125g plain flour
1 tsp baking powder
100 butter, softened
150g peanut butter
175g brown sugar (I used light muscovado)
1 egg, beaten
1 tsp vanilla paste or extract
100g of dark or white chocolate, chopped into small chunks
100g strawberries, cut into slices
100-200g waffles or malt biscuits (I used the lamely named Arnotts Malt’O'Milk biscuits) or any biscuits/cookies, processed to crumbs in a food processor
Note: this recipe makes a very small amount of brownies (which is never a good idea for a brownie recipe, methinks). You’d have to make this in a bread tin if you wanted the brownies to be a decent thickness. I have a huge brownie tin, so I do a double quantity of this recipe, but if you have just a standard brownie tin (those ones that are around 25cm by 15cm), maybe do 1.5x the quantity. You might have to cook the brownies a bit longer if you do opt for thicker ones, which is fine.
Preheat oven to 170ºC. Butter your tin and line the bottom with baking paper.
In a bowl, mix together the flour and baking powder (sift it if you think that’s necessary, but given that most flours are pre-sifted it’s probably fine).
In the bowl of an electric mixer (or in a normal bowl using a wooden spoon), cream butter and peanut butter together until smooth and light and soft. Add sugar, egg and vanilla and beat until combined. Add flour and baking powder, mix until just combined, then fold through the optional extras (chocolate and/or waffle crumbs or whatever) until evenly distributed.
Put batter into the tin, smooth it out to an even thickness (it will be quite thick and sticky), then bake for 20-30 minutes (it depends on the thickness, so keep an eye on it) until golden brown all over. A cake tester or skewer inserted into the middle kind of comes out clean when the blondies are done, although the moistness of the blondies can make this a difficult way of gauging how done they are. But if you don’t mind fudgy brownies/blondies, these are almost impossible to undercook.
Allow to cool in the tin before taking it out and cutting it into squares. (I often refrigerate the whole thing for a few hours or overnight to make cutting it up easier.)
Piqueras-Fiszman, et al. (2011). Does the weight of the dish influence our perception of food? Food Quality and Preference, article in press.