Menu psychology put to the real-life test: Can we persuade diners to order a vegetarian dish by changing the menu card?

It is not easy to select from a menu in a restaurant. Doubts may come up at the sight of the abundance of delicious choices. Do I want an appetizer, dessert or both? The menu card, also called the 'silent salesperson' is one of the most powerful tools that a restaurant has to market its dishes. Dozens of 'menu psychology' studies have shown that there are a number of ways in which diners can be influenced towards ordering more profitable items. For example, a field study showed that changing the description of food on a menu (e.g. ‘legendary chocolate mousse pie’) increased sales by 27%. 


Renske Hermans

But can we also use these psychological insights to encourage diners to order a vegetarian dish as a sustainable alternative to meat? Eating meat puts a lot of pressure on the environment. Could a restaurant menu card be used as an inexpensive and simple nudge to enhance consumer choices in the direction of societal best interest? That is; can we seduce diners to go for the vegetarian dish while eating out?

Renske Hermans took up the challenge to study this intriguing question for her master thesis project. This year, she is going to graduate from the Master Management, Economics and Consumer Studies at Wageningen University. In cooperation with Hotelschool The Hague we conducted a six-week field study in their fine dining restaurant 'Le Debut'. While enjoying organic and locally produced food in this restaurant, up to 50 guests are served by the school's international students. The kitchen is also run by hotel management students under guidance of instructors. 
 


Restaurant Le Debut at Hotelschool The Hague

After discussion with Chef Stefan, we decided to strategically place a tasty vegetarian dish at the heart of a so-called combo-menu including a starter, main course and dessert. We expected that this would lead to more sales of vegetarian dishes than placing them in the separate listing of menu items. In fast-food chains, 'combo-meals' are common options in which you get a pre-defined combination meal (sandwich, fries and drink) for a single price. For many consumers, they are an incentive to purchase something extra. It is similar to the practice of 'bundling' in retailing in which several items are sold for one price.

We called our combo-menu 'Menu Gastronomique', and developed one meat combo-menu and one vegetarian combo-menu. For the vegetarian menu, we took meat replacers of the famous Dutch ‘Vegetarian Butcher’, known for his innovative meat substitutes with a spectacular taste and texture. For two non-consecutive weeks, the vegetarian ‘Menu Gastronomique’ was available for €25.50. For a similar period and price, a meat ‘Menu Gastronomique’ was offered. As a control, we also had a 2-week period without any combo-menus, although diners could still select the same vegetarian and meat dishes. During these six weeks, we kept track of sales data. After dinner, we also asked diners to fill out a brief questionnaire about their dining experience and the menu card. 

Menu card in one of the periods of this nudge field study

Results of our study showed that dining in The Debut was a very positive experience for all customers. Across the entire six weeks, customers liked the menu and thought it provided good value for money. Some of the guest enthusiastically wrote about their dining experience at the questionnaire form. One diner wrote: ‘I was pleasantly surprised to have a vegetarian option! Very tasty’ and another diner commented on the vegetarian menu: ‘It looks delicious!”.


Unfortunately, our menu card nudge did not persuade a larger group of diners to go for the vegetarian dish. Less than one-fifth of the diners selected the vegetarian dish, and this number was not significantly different across the three menu card-periods. There are a few potential explanations. For example, it could be that we did not reach enough so-called ‘flexitarians’; meat-reducers who consume meat only several days a week. It might also be that this nudge was too gentle to convince diners to try something new. Previous research showed that meat replacers are typically seen as less tasty while at the same time dining out tends to grant people a license to indulge. Perhaps our nudge can seduce consumers in other settings, such as a workplace canteen.