Detailed Explanation of the Processing Technology for Dry-Packed Salted Almond Canned Goods

(1) Process flow

Raw material acceptance → sorting → cleaning → peeling → rinsing → color protection → pre-boiling → soaking → re-boiling → grading → seasoning mixing → canning → exhausting → sealing → inspection → sterilization → cooling

(2) Description of operating points

(1) Raw material acceptance: Use fresh, plump, dry almonds with white kernel flesh, free from insect damage, mold, and foreign matter.

(2) Sorting: Remove insect-damaged, moldy, shriveled, broken and other substandard kernels and foreign matter.

(3) Cleaning: Put the sorted qualified almonds into a flowing clean water tank, wash off the mud, sand, foreign matter, etc. on the surface, scoop them out and drain the water.

(4) Peeling: Pre-boiling peeling method: put the cleaned almonds into boiling water, pre-boil for 12-15 minutes, scoop out after boiling and put into flowing clean water to cool thoroughly, then rub with a wooden board or use a rubbing machine to rub off the inner skin.

Peeling liquid peeling method: put the cleaned and drained almonds into a peeling liquid at 95-98°C (a mixed aqueous solution of 0.2%-0.4% fruit and vegetable peeling agent and 2%-4% sodium hydroxide) for 3-5 minutes, scoop out and quickly cool and rub to peel, with appropriate force to keep the kernels intact. The ratio of almonds to peeling liquid is 1:2.

(5) Rinsing: After peeling, wash the almonds with flowing clean water to remove the inner skin, fragments, etc.

(6) Color protection: Scoop out the rinsed almonds and promptly put them into a color protection liquid (a mixed aqueous solution of 2% salt, 0.2% citric acid, and 0.1% sodium metabisulfite), protect color for about 2 hours, the ratio of almonds to color protection liquid is 1:2, after color protection scoop out the almonds, put them into flowing clean water, and wash off the residual color protection liquid.

(7) Pre-boiling: After scooping out the washed almonds and draining the water, put them into the pre-boiling liquid, heat to a slight boil for about 15 minutes, and stir continuously to promote the volatilization of toxic substances such as hydrocyanic acid, then scoop out and put into flowing clean water to cool.

Pre-boiling liquid: 0.1%-0.2% citric acid aqueous solution or 0.1% hydrochloric acid aqueous solution.

(8) Soaking: Scoop out the cooled almonds, put them into clean water and soak for 30-50 hours, replace the soaking water once every 4 hours, or use flowing clean water for soaking, and pay attention to removing bad kernels and foreign matter at any time.

The cooled almonds can also be soaked in a soaking liquid (a mixed aqueous solution of 8%-10% refined salt, 0.1%-0.2% citric acid, and 0.1%-0.15% sodium metabisulfite), the ratio of almonds to soaking liquid is 1:1.2, subject to completely submerging the almonds, the soaking time is 30-50 hours, and it is appropriate that the almonds have no bitterness or only slight bitterness. After scooping out, put them into flowing clean water and wash off the residual soaking liquid.

(9) Re-boiling: The method is the same as pre-boiling.

(10) Grading: Scoop out the almonds after re-boiling and cooling for grading, remove insect-damaged, discolored, moldy, and broken almonds; the almonds should be in granular and flake form.

(11) Seasoning mixing: Formula: almonds 20 kg, Vc 0.01 kg, refined salt 0.300 kg, monosodium glutamate 0.090 kg. Method: The refined salt, monosodium glutamate, and Vc should be dried beforehand and sifted through 70-100 mesh, then mixed evenly and mixed into the almonds; the seasoning mixing should be uniform and consistent.

(12) Canning: Net weight 140 g or 280 g, packed in glass jars.

(13) Exhausting and sealing: Exhaust sealing, center temperature above 80°C; vacuum sealing, vacuum degree 0.06-0.067 MPa

(14) Sterilization: For net weight 140 g, the sterilization formula is 5'-55'/100°C; for net weight 280 g, the sterilization formula is 5'-60'/100°C.

(3) Product quality indicators

1. Sensory indicators

Color: The almonds are milky white or white, with a small amount of almond fragments allowed; Taste and odor: It should have the taste and odor that dry-packed salted almond canned goods made from processed, seasoned, and canned almonds should have, with no off-flavor; Texture and form: The almonds are peeled, debittered, with moderately soft and hard texture, in granular or flake form, with no more than 15% broken almond fragments allowed; Impurities: Not allowed.

2. Physicochemical indicators

Net weight: There are two types, 140 g and 180 g, with a tolerance of ±5% per can, but the average of each batch shall not be lower than the net weight; Sodium chloride content: 0.8%-1.5%; Hydrocyanic acid content: No more than 5 mg/kg.