Processing Technology of Common IQF Vegetables
- Cucumber Corn and Spinach
2023-12-2
Sweet corn
Take the mature sweet corn, yellow or white is ok. Corn kernels should be full,
neat, remove too old raw materials. Due to the quick progress of maturation after
harvesting, IQF freezing process should be completed as fast as possible. Frozen
corn can be frozen with or without cob. Generally the corn is frozen without cob,
The process is as follows: remove the skin, pick off the tassel, use corn cutter
to cut the kernels from cob, blanching in hot water at 100 ℃ 3 ~ 4min, take out
and cool to below 10 ℃ in short time. Freeze in a freezing device below -30 ° C
for 10-20 min, and pack in a plastic bag after freezing.
Another method is without blanching, remove the tassel of green corn, leaving 1
to 2 layers of skin, freezing directly, then packing and persevering, the quality
is also very good.
Cucumber
IQF frozen cucumber is a quite popular frozen vegetable. Raw materials should be
fresh, less seeds, The autumn cucumber is the best. Picking and processing in the
same day, storing time is not more than 24h. The raw material should be cleaned
when send to plant. Soak in the concentration of 5 ~ 10g/L water edible calcium
chloride solution for about 20min. Then clean it again. Slice or dice cucumber according
to cooking habits, During slicing and dicing, it should avoid the water loss, because
if the water lost too much , it will be frozen to block in IQF freezer. The fluidized
bed IQF freezer is competent for that. After freezing, quantitative packaging, preserved
in the warehouse of -18 degrees. Prevent extrusion in cold storing, transportation
and sales.
Spinach
Select broomy leafy species. Raw material should be fresh, dark green, no yellow
leaves, no pests and diseases, the length is about 150 ~ 300mm. interval time between
harvest and freezing process should be as short as possible, storage time shall
not exceed 24h. Picking, remove yellow leaves, cut roots and clean spinach one by
one in pretreatment.
The old degree, moisture of spinach roots and leaves is different, blanching time
for root should be longer, leaves should be shorter. The process way: place the
cleaned spinach by roots down in baskets. When blanching, put the roots in hot water
for 30s, and then soak the whole basket into hot water for 1 min. in order to preserve
the spinach green, spinach should be cooled to less than 10C after blanching, finally
drop water after cooling. Make a bunch of 500 kg spinach and pack into plastic bag,
seal it, put the packages in low temperature of -30℃ for 20 min freezing, after
freezing the spinach become is very crisp and easily broken, Take light, usually
packed in a box of 20 bags.
