Touch, taste, and smell are an underexplored design space in the context of interactive experiences. The integration of the physical and chemical senses into technology will transform existing interaction paradigms. Multisensory research creates new knowledge and stimulates the appetite for innovation. Digital Taste Interface is a method for simulating the sensation of taste by actuating the human tongue through electrical and thermal stimulation. Three characteristics of taste experiences which are temporality (the duration of the taste experience indicated from left to right), affective reactions (green pleasant, red unpleasant, and orange neutral experience) and the embodied mouth feeling are combined for each of the five basic tastes (sweet, sour, salty, bitter and umami). Studying these underexploited senses not only enhances the design space of multisensory HCI but also helps to improve the fundamental understanding of these senses along with their cross-sensory associations.

According to the journal, HCI is still facing different challenges related to the ‘how’ of stimulating the sense of taste but within HCI, taste simulation is achieved through the use of chemical stimulation or through electrical and/or thermal stimulation of the users’ tongue. In the journal, they had extended the discussion presented by Spence where they made a review regarding the specificities of gustatory interfaces using both chemical and electrical/thermal stimulation approaches. It also introduced two concept of gustatory interfaces which involves five basic taste (inspired by LOLLio, taste-based game interface) and new interaction concept exploiting principles of acoustic levitation. For Chemical based stimulation approach, chemical compound (in solid or liquid) are given to user with five basic tastes (bitter, sweet, sour, salty and umami). For thermal/electrical stimulation approach, a silver wire was placed on the tip of tongue to stimulate the sweet, sour and bitter taste and a reference electrode were placed on the left wrist of the subject. Sweet taste was created by warming the front edge of the tongue while sourness and/or saltiness by cooling it. Chemical based stimulation is one step ahead as it covers broad range of taste experience than electrical/thermal based stimulation. The first new concepts introduced in the journal are TasteBud where it composed of six bottles of solution where it contains one basic taste each and one with water. The taste delivery was controlled by Arduino. TasteBud is a standalone unit that offer delivery of one or multiple taste in one trial. The second one is TastyFloats which is a novel system that uses acoustic levitation to deliver food morsels to users’ tongue. This concept levitates food item themselves and facilitates a contactless delivery food into users’ mouth. This concept also has a hygienic advantage. The Gustatory interfaces are interesting and quite challenging, hoping that the future research is inspired by the existing effort in gustatory interface design.

This journal describes the development of a new interface for multisensory communications called “Thermal Sweet Taste Interface”. As the writer stated, there are five most fundamental tastes which are sweet, sour, bitter, salty and savory. The most pleasant taste of the five is probably sweet taste. This paper considering multisensory communications, sensing and actuating sweet taste digitally is an extremely important requirement. Almost all the sweet taste interfaces that were developed earlier in the field of Human-Computer Interaction used chemicals to generate sweet sensations. This device uses a copper electrode attached with a Peltier module that interfaces with the surface of the tongue and may allow users to experience sweet taste sensations. This interface is capable of generating virtual sweet sensations just by rapidly changing the temperature of the surface of the tongue. This device may enhance new user experiences in different disciplines such as Human-Computer Interaction, New Media Arts, Internet Communication and Medicine.

This journal explains that the virtual reality applications that are used for taste sensations are not effective because it needs to be maintained and chemicals need to be refilled. It has suggested that A new solution that does not require chemicals can be a beneficial advanced step for VR. An invention called “Thermal Taste Machine” is developed as a new computer-controlled thermal taste device with a step where the silver electrode of the invention being placed on top of the tongue. Then, the temperature on the surface of the tongue can be modified from 25 ◦C to 40 ◦C while heating and from 25 ◦C to 10 ◦C while cooling. The results obtained by the researchers suggested that the tongue produces sweetness and lessens the sensitivity of metallic taste by rapidly heating the tongue, while the pleasantness and mint taste can be produced by cooling the tongue. TRPM5 (Transient receptor potential cation channel subfamily M member 5) taste channel can enhance the sensibility of sweetness, bitterness and umami tastes by being stimulated after applying thermal stimulation on the tongue. An objective of the research from this journal is to develop an effective thermal taste device that can easily integrated into virtual reality and digital communication. The device developed by the authors is the first thermal taste device that can enhance the sweet sensation. It has also suggested that a rapid rise in temperature may produce more intense sweet sensations. The authors also explain that they believe the invention of the device will create a quantum jump in the field of virtual reality.

The rituals of cooking, ordering, and dining could be influenced by technology. In the Hunger Games installation the potential awkwardness of dining with strangers was mitigated by creating a shared challenge that required cooperation to solve. Also for familiar diners the installation created a new dining experience. The Food roulette app and interactive tables changed the ritual of ordering food. In particular, personalised menus based on a guest’s food preference and allergies could streamline the ordering process. However, it should be noted that replacing the human waiter with an impersonal system for placing an order makes ordering a less social process. To us it seems very unlikely that this would become a trend in a sector where the difference is made through personal attention and heartfelt hospitality. Changing the eating behaviour of guests proved possible as seen by the Thunder Dinner installation. 

However, care should be taken when designing the stimulus that is meant to change the behaviour. We observed that our stimulus, that was meant to be a deterrent for fast eating, was sometimes perceived as interesting or fascinating leading to behaviour intended to trigger the stimulus. We were able to change the flavour experiences with installations that create cross-modal stimuli. Projecting a coloured animated shape on a food item, in this case yoghurt, changed the taste. The taste of yoghurts that were presented with red/rounded still visuals were rated as more sour than when presented with green/angular stills, but when the visualizations were animated this effect reversed. If the yoghurts were presented with green/angular animated visuals the yoghurts were rated as sourer than when they were presented with red/round animated visuals. The implication is that mixed reality technology can be utilized to systematically investigate taste associations and taste perceptions. This multi-modal approach could not only result in fascinating installations and food experiences, but could also shed further light on the multi-modal perception of flavour.

 

This can also be done by using the dedicated Android application. The conventional switch boards will be added with a touch screen or replaced with a touch screen to match the taste of the user's home decor. PIR (Passive Infrared Sensor) sensor will be used to detect human detection and automate the on and off functionality. Besides, we can now conclude that a low cost solution to the need of automating & switching appliances is possible with the Raspberry Pi. 

 

NEXT GENERATION FOOD EXPERIENCES

Summary;

This journal is about new interactions being used to create and modify taste and smell sensations by electrical, magnetic and thermal interfaces. The authors describe how those technologies can create and modify new interactions for multiple of industry such as for food, communication, computing and marketing. The authors propose the idea of digital olfaction and gustation as input and output for interaction for making and experiencing digital portrayal of food. The interfaces pointed up from this journal are electrical interfaces which are electric sour interface and electric smell interface, magnetic interface which are magnetic food and magnetic levitation platform and finally, thermal interface which is sweet thermal taste interface. From this journal, it is stated that the new ways are able create content and new knowledge of food that is capable to be learned, created and shared in new fascinating ways. 

·         Determine which sensory experiences we can design for and how to meaningfully stimulate them when people interact with technology

·         Build on previous frameworks for multisensory design while also creating new ones

·         Design interfaces that take into account the relationships between the senses (for example, integrating taste and smell when it comes to flavour

·         Understand what limitations come into play when users must monitor information from more than one sense simultaneously.

As a community, the writer need to further explore and understand the possibilities behind sensory stimulation and develop design frameworks that provide both quantitative and qualitative parameters for sensory stimulation. Here, they have highlighted that there are opportunities to enhance designers’ and developers’ abilities to create meaningful interactions and make use of the whole spectrum of multisensory experiences. 

 
Summary;

The advancement of Human-Computer Interaction has brought the world into a new technology that provides the taste sensation virtually, without having to actually use the real ingredients needed. Besides not being able to adjust the flavours of the food and drinks, some actual ingredients are really harmful to human body, as most of them contain artificial chemicals. By bringing in the digital taste technology, flavours and ingredients can be adjusted virtually while providing the real taste sensations. This virtual taste technology is acquired by integrating electrical stimulation on the tongue and superimposing virtual colours on the beverage. The two appliances proposed by the writers are eating and drinking utensils, which is bottle and spoon.  Both are embedded with digital control system and two silver electrodes that connects with user’s tongue when eating or drinking, and are made to enhance the taste sensation. To facilitate immersive taste experience, the writers explore a new methodology to superimpose virtual ingredients for primary taste sensations such as salty, sour, and bitter. There are three stimuli that are used to simulate the virtual taste sensation. They vary from green for sour, with 600Hz frequency, blue for salty, with 200Hz frequency, and red for bitter, with 600Hz frequency. After conducting the experiments, the result came with 70% accuracy. However, some people might have different taste preferences. The methodology introduced by the writers is a great way to manipulate and adjust the taste sensations without adding additional flavouring ingredients or artificial chemicals.