# Physicochemical and Sensory Analysis of Apple Cream Fillings for Use in the Pastry Industry
## 1 Introduction  
Apple-based fillings are extensively used in the food industry, particularly in pastries and desserts, because of their balance of sweetness and tartness, as well as their ability to enhance texture and flavor. However, achieving a stable and attractive apple filling remains a challenge, as formulation and ingredient interactions influence physicochemical properties and sensory perception [1]. Apples (_Malus domestica_) are rich in dietary fibers, vitamins, and bioactive compounds, making them a functional ingredient in food formulations [2]. The use of apple pomace and cubes in the fillings not only improves texture and flavor, but also supports sustainable practices by reducing food waste [3, 4]. Physicochemical parameters such as water activity (a\({}_{w}\)) play a crucial role in determining the shelf stability of food products, with lower a\({}_{w}\) values reducing microbial growth [5]. In addition, pH and tittralble acidity influence flavor and preservation, affecting consumer preference. The viscosity of apple-based fillings affects texture, mouthfeel, and processing performance, making it a critical factor in formulation optimization [6]. Furthermore, hydrophilic andhydrophobic interactions significantly determine product stability and sensory appeal [7]. Texture modifiers, such as potato starch, help maintain consistency, ensuring the structural integrity of the filling over time [8; 9]. Apple punees and peel extracts contribute to high fiber content and antioxidant activity, improving nutritional value and sensory characteristics [1]. Studies indicate that apple inclusions improve textural complexity, making products more desirable [10]. Research on fruit-based creams has highlighted the importance of particulate matter in influencing consumer perception and general acceptability [3]. Processing techniques also play a crucial role in optimizing rheological and structural attributes, ensuring desirable sensory outcomes [4]. Malic acid, naturally present in apples, contributes to tartness and improves flavor balance in fruit-based formulations [11]. Preservatives such as potassium sorbate are commonly used to extend the shelf life of apple-based fillings by inhibiting microbial growth [12]. Natural or artificial sweeteners, including dextrose, influence not only taste but also moisture retention and texture, playing an essential role in formulation stability [13]. The inclusion of cinnamon further enhances sensory appeal by providing characteristic warm and spicy notes, complementing the natural apple flavor while also exhibiting antimicrobial properties [14]. In addition, the color stability of apple fillings is influenced by oxidation reactions, which can be mitigated using antioxidants and pH adjustment [4; 6; 15]. Consumer preference for natural and minimally processed ingredients has driven innovation in fruit-based fillings, with manufacturers increasingly opting for clean-label formulations [16]. The demand for texture-rich products has also spurred the use of structural enhancers such as hydrocolloids, which improve stability and mouthfeel [17]. The production of new apple cream fillings with unique characteristics is a challenge for the pastry industry. The combination of different raw materials creates complex flavor and textural profiles in the final products, i.e., the use of cinnamon as a spice for unique fragrance and flavor, dextrose as a sweetening and stability agent, xanthan gum as a stabilizer improving textural characteristics (e.g., increased viscosity, pleasing texture), potato starch as a thickening agent for sauces and as a gluten-free ingredient in baking improving texture and retaining moisture, apple flavoring improving both taste and texture, malic acid ameliorating flavor, extending shelf life and improving rheology and dried apples retaining their texture, color, and taste with fresh apples.