Production of chocolate with soy milk in a ball mill

Abstract

© 2016 Nova Science Publishers, Inc. Today, food not only needs to satisfy hunger and provide the necessary nutrients for the body, but also to prevent the occurrence of diseases that are related to nutrition and improve the physical and mental health of consumers. Functional foods can improve the general condition of the body, reduce the risk of some diseases and furthermore be used to treat some diseases. Given the growing popularity of functional foods and frequent consumption of confectionery products, especially chocolate, the goal of this chapter was to create innovative, functional chocolate - chocolate with soy milk. Chocolate with soy milk is composed of 8-10% soy proteins, which have a positive impact on human health. Soy milk contains more protein and less fat than cow’s milk. It is characterized by the absence of cholesterol and lactose, has a low content of saturated fatty acids, while the content of polyunsaturated fatty acids is significantly higher than in cow’s milk. This chocolate is not only interesting because of its health effects, but also because of its textural properties. The greatest impact on the thermoreological, thermal and textural properties of chocolate have the composition of the ingredients, fat content, selection of emulsifiers, solid particle size distribution and particle packing method. In milk chocolate the ratio of milk fat and cocoa butter determines the quality of chocolate and today everything about it is well known, while the ratio of soy milk - cocoa butter has not been completely defined. For this chapter, chocolate was produced in an unconventional way, i.e., in a ball mill applying variable refining time (30, 60 and 90 minutes) and pre-crystallization temperature of chocolate mass (26, 28 and 30°C). The chocolate was produced with 20% of soy milk powder. The quality of chocolate was monitored by investigating nutritive composition, polyphenol content, hardness of chocolate, solid triglyceride content (SFC), thermal characteristics, rheological parameters (Casson yield flow (Pa), Casson viscosity (Pas), the thixotropic loop area, elastic modulus and creep curves) as well as sensory properties. Results showed that chocolate with soy milk had a higher nutritional value and better antioxidant properties than chocolate with powdered milk. The proteins of the soy milk, which are capable of forming a gel if the protein concentration is greater than 8%, lead to the viscoelastic behavior of the chocolate mass. Rheology of the chocolate mass with soy milk depends solely on the soy proteins, while thermal and sensory properties and content of solid triglycerides depends on the fatty phase, i.e., soybean oil. In order to maintain optimal sensory quality, hardness as well as melting resistance of chocolate, it is necessary for the chocolate with soy milk to be refined longer in a ball mill, however also to use lower temperatures for pre-crystallization.