Drying of a mixture of milk-blackberry pulp using spouted bed, spray dryer and Freeze drying: quality and stability of the powders

• Grant number: 14/12527-6
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2014
• End date: June 29, 2015
• Field of knowledge: Agronomical Sciences - Food Science and Technology - Food Engineering
• Principal Investigator: Miriam Dupas Hubinger
• Grantee: Matheus Boeira Braga
• Host Institution: Faculdade de Engenharia de Alimentos (FEA). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Blackberry is a seasonal fruit, climacteric and highly perishable, whose availability is limited by the periods between crops. Blackberry drying aims at enhancing its conservation, therefore, the development and application of drying techniques such as spray drying, spouted bed drying and freeze drying, which could increase the shelf life of this product is of great interest. The high reducing sugar and water content of pure blackberry pulp may result in low powder production during the drying process. On the other hand, drying of whole milk has shown good powder yields and product quality. A milk-blackberry mix paste becomes an alternative which may improve the process efficiency, reduce post-harvesting waste, and increase the shelf life of the product without significantly altering its nutritional characteristics. In this context, the milk components act as wall materials, encapsulating flavonoids from blackberry pulp which include the anthocyanins. Therefore, the aim of this project is analyzing the drying of a mixture of milk-blackberry pulp using three different drying methods (spouted bed drying, spray drying and freeze drying), with emphasis on powder quality (solubility characteristics and physical and physicochemical characteristics), and powder stability during the storage.