Flash Vacuum Expansion (Fve) A Novel Food Processing Technology

Due to consumer and industrial demands for healthy, convenient, fresh and quality food with high yield, processing of fruits and vegetables by different novel method is rapidly expanding now days.

Flash vacuum expansion is one such technology for extraction of healthy and quality products efficiently. Today it is increasingly used as a pre-treatment of grapes before fermentation or for production of tomato puree.

Flash vacuum expansion

Flash vacuum expansion is a process where a heated product is rapidly exposed to low pressure, or vacuum, causing interstitial water in the product to rapidly flash and rupture a portion of the tissue. This process has potential to aid expression and improve extraction of potentially healthy components from fruits and vegetables.

Working principle

Flash vacuum expansion (or flash release) is technology developed to improve yield, nutritional and sensory quality of food products. In this technique, plant materials are steam heated to 60-90 °C and is rapidly introduced to a vacuum chamber at 1-10 kPa. absolute pressure. At this reduced pressure (high vacuum), the boiling point of water in the tissues is much lower than the temperature of the plant material (60-90 °C). Due to formation of micro channels inside the tissues, instantaneous evaporation of constituent water occurs.

Steps in FVE process

There are two steps involved in the flash vacuum expansion process, they are steam heating at 60- 90 °C and immediately followed by vacuum expansion stage with highest vacuum and reduced pressure of 1-10 kpa. Then must or the vacuum expanded food is collected at the collecting end of the system and the evaporated water is collected in condenser and liquified by using the cooling agent, then the obtained aromatic liquid is collected and stored for the further use.