Processing technology of quick-frozen French fries

Processing technology of quick-frozen French fries

Processing technology of quick-frozen French fries flow

Fresh potato selection → washing → peeling → cutting or slicing → blanching → drying → frying → pre-cooling → quick freezing → packaging → freezing

Operation points

(1) Fresh potatoes inspection and selection: select potatoes with no mold, no insect eyes, no deterioration, shallow bud eyes, and smooth surface, and remove green buds and shrunken skins.

Physical and chemical indicators should be tested before production. The quality of physical and chemical indicators directly affects the color of the finished product. The reducing sugar content of potatoes should be less than 0.3%. If the reducing sugar content is too high, it should be placed in an environment of 15-18°C and adjusted for 2 to 4 weeks.

(2) Cleaning: With the help of water power and screw mechanism, the potatoes are cleaned.

(3) Peeling: In order to improve production capacity and ensure product quality, mechanical peeling or chemical peeling should be used. Excessive peeling should be prevented when peeling, which increases raw material consumption and affects product output.

(4) Cut strips (slices): The peeled potatoes are rinsed with water to wash off the potato skins and residues on the surface, and then sent to the slicer with a conveyor belt to cut into strips or slices. The thickness of the product should meet the quality requirements . Generally, it is 1.5 to 2.0 mm, and potato chips are generally about 3 mm.

(5) Rinsing and blanching: The purpose of rinsing is to wash away the starch on the surface to avoid product adhesion or oil pollution during the frying process. The purpose of blanching is to inactivate the enzymes in the potato strips (slices) to prevent enzymatic browning and affect product quality. The methods used include chemical methods and physical methods. The chemical method uses chemical solution soaking; the physical method uses hot water at 85-90°C for blanching.

(6) Drying: The purpose of drying is to remove excess water on the surface of the potato strips, thereby reducing oil loss and decomposition during the frying process, while keeping the blanched potatoes crisp. However, care should be taken to avoid sticking due to excessive drying. Compressed air is usually used for drying.

(7) Frying: The dried potato strips are sent to the frying equipment by the conveyor belt for frying, the oil temperature is controlled at 170-180°C, and the frying time is about 1 min.

(8) Quick-freezing: The fried product is pre-cooled and then quickly frozen in a quick-freezing machine. The quick-freezing temperature is controlled below -36°C to ensure that the core temperature of the potato product drops to below -18°C within 18 minutes.

(9) Refrigeration: The potato products after quick-frozen should be bagged and boxed quickly, and then stored in a freezer below -18°C