Production Line Introduction

This concentrated and blended lemon juice processing production line is specifically designed for the concentration, reconstitution, and standardized blending of lemon juice. Its capacity can be flexibly configured, covering an annual output of 100 KL to 50,000 KL, achieving continuous and automated processing from fresh fruit raw materials to finished concentrated or reconstituted juice. The system integrates core process units such as extraction, enzymatic hydrolysis, concentration, formulation blending, and aseptic filling, focusing on solving key technical problems such as precise control of the sugar-acid ratio, removal of bitter substances, and extension of shelf life. All equipment is constructed of SUS304 or SUS316L food-grade stainless steel, strictly adhering to food hygiene standards. It is compatible with both clear and cloudy juice processing routes to meet diverse product needs.

Process Description

Pretreatment and Juicing: The raw materials are cleaned by a bubbling washing machine to remove impurities, and defective fruits are removed by a fruit inspection machine. Subsequently, a crusher processes the juice, and a screw juicer extracts the lemon juice, separating the peel from the pulp.

Enzymatic hydrolysis and clarification: The extracted crude juice is pumped into an enzymatic hydrolysis tank, where pectinase is added at 45°C to 55°C for liquefaction, lasting approximately 30 to 90 minutes. The suspended solids and pectin are then separated using a disc centrifuge or ultrafiltration system to obtain clarified juice.

Concentration and debittering: The clarified juice enters a multi effect falling film evaporator, where water is evaporated under low-temperature vacuum conditions, increasing the concentration to 42°Brix to 65°Brix. To address the characteristic bitterness of lemons, a resin debittering column is incorporated into the process to reduce the limonene content.

Blending and homogenization: The concentrated juice enters a blending tank, where purified water, white sugar syrup, citric acid, and flavoring are added in precise quantities according to the process formula to adjust to the target sugar-acid ratio. The mixture is then refined into particles using a high-pressure homogenizer and degassed under vacuum to remove dissolved oxygen and prevent oxidation and discoloration.

Sterilization and Filling: Homogenized material enters an ultra-high temperature (UHT) sterilizer, maintained at 121°C to 135°C for several seconds to achieve commercial sterility. The sterilized material then directly enters the aseptic filling system, quantitatively filling it into aseptic bags or bottles and sealing it.

Basic Equipment Components

Screw Juicer: Utilizes a screw shaft to propel the fruit pulp and generate increasing pressure within the pressing cage to achieve liquid-solid separation. It features high juice yield and stable operation.

Enzymatic Hydrolysis Tank: Equipped with a jacketed heating and high-shear stirring device, this reaction vessel is used to precisely control the temperature and time of the enzyme reaction, promoting pectin decomposition.

Disc Centrifuge: Utilizes a high-speed rotating disc array to generate a centrifugal force field, rapidly separating fine fruit pulp fibers and colloidal particles from the juice, significantly reducing juice turbidity.

Multi-Effect Falling Film Evaporator: Utilizes the principle of thin-film heat transfer, causing the juice to flow in a film-like manner on the inner wall of the heating tube and evaporate. It is typically combined with TVR technology to recover secondary steam, achieving low-temperature, high-efficiency concentration.

Ultra-high temperature (UHT) sterilizer: Employs tubular or plate heat exchange structures to rapidly reach sterilization temperature and cool the juice quickly, minimizing the destruction of heat-sensitive nutrients.

Aseptic filling machine: In an aseptic environment, it quantitatively fills sterilized juice into sterilized containers. It is typically equipped with nitrogen purging to reduce headspace residual oxygen and extend shelf life.

CIP cleaning system: Composed of acid and alkali storage tanks and centrifugal pumps, it automatically cleans and disinfects the entire pipeline and tank system through a closed-loop circulation, ensuring food hygiene and safety.