## 5 The Use of Eye Tracking and FaceReader for Food Products  
In recent years, consumer behavior research has increasingly integrated innovative technologies to gain deeper insights into how food products are perceived and evaluated [120]. Eye tracking and FaceReader have emerged as powerful tools, providing valuable data on consumer attention, emotional responses, and sensory engagement during food product evaluation. Eye tracking technology monitors eye movements and gaze patterns, offering a unique way to measure visual attention to food packaging, product features, and advertising [121]. This technology enables researchers to identify visual cues that attract consumer attention, such as product color, shape, and labeling. It can be effectively applied in face-to-face and online contexts, including healthcare marketing, to enhance consumer understanding and optimize marketing strategies [122]. Researchers can identify key product attributes that attract attention by tracking where and for how long consumers focus their gaze. For example, a study by [PERSON] and [PERSON] [123] showed that prominently positioned nutrition information attracts significant consumer attention, highlighting how label placement can influence food choices. Beyond product evaluation, eye tracking is pivotal to food sustainability research. A recent systematic review by [PERSON] [124] highlights how eye tracking helps uncover consumers' growing interest in eco-friendly products, offering valuable insights for sustainable product development and marketing. Studies by [PERSON] et al. [125] compared real-life and virtual eye-tracking tasks, demonstrating that while virtual eye-tracking data can reflect visual preferences, these data do not fully capture the complex cognitive processes involved in real-life food choices. Although eye-tracking data in virtual environments can reflect visual preferences, they do not fully capture the complex cognitive processes involved in real-life food choices. Factors such as multisensory influence, social context, and physical product interaction are crucial in consumer behaviors and are difficult to replicate in virtual settings [121]. Furthermore, studies have shown that eye-tracking technology captures different attention phases. The \"orientation\" phase occurs when consumers' gaze is drawn to visually salient features, while the \"discovery\" phase involves shifting focus to specific details such as logos or product names. As described by [PERSON] et al. [126], these phases are essential for understanding how consumer attention is initially captured and later distributed across different product attributes. The influence of visual cues extends to the packaging design. [PERSON] et al. [127], demonstrated that specific packaging elements, such as font weight and illustration size, significantly influence gaze duration and fixation count, with illustrations generally attracting the most attention. These findings highlight how targeted packaging features can shape consumer preferences, enhance product recall, and underscore the importance of strategic design elements. Eye tracking contributes to understanding consumer decision-making processes by showing how visual cues impact product choice and purchase behavior. It provides a comprehensive view of how eye movements influence food-related decisions, with visual attention playing a critical role. [PERSON] and colleagues [128] further illustrated this in their study of chocolate packaging, showing that color, logos, and arrangement strongly influenced consumer fixation and preferences. Notably, familiar packaging designs evoked more positive emotional responses, such as happiness, suggesting familiarity and appealing visual elements drive consumer interest and satisfaction. Another valuable tool for studying consumer behavior toward food products is FaceReader software (2023), which analyzes facial expressions to detect emotional responses in real-time.