1. Large potato starch grain size
Different varieties of potato starch have different grain sizes. Generally, the grain size of potato starch is 35.105 um. Oval-shaped potato starch with large grain size and round potato starch with small grain size. Given certain nutritional conditions and environmental factors, potato starch grain size will undergo a series of changes, resulting in larger grain size than oat starch, purple potato starch and wheat starch.
2 Potato starch has high viscosity
The viscosity of potato starch depends on the degree of polymerization of its amylose. The paste viscosity of potato starch, corn starch, oat starch and wheat starch was compared. The experimental results showed that the content of potato amylopectin was more than 79%, and the average peak value of potato starch was 2988, which was higher than that of corn starch (589), oat starch (99) and wheat starch (298).
3 Low gelatinization temperature of potato starch
The gelatinization temperature of potato starch is 64C on average, which is lower than that of corn starch (72C), wheat starch (73C) and cassava starch (65 "C) and sweet potato starch (80'C) of potato starch.
Although potato starch particles are large, there are mutually exclusive phosphate group charges in the molecular structure of potato starch, and the internal structure is weak, so the expansion effect of potato starch is very good.
4. Potato starch has strong water absorption
It is well known that starch has a certain water absorption capacity, and its water absorption capacity changes with the change of temperature.
The content of potato starch is very high. Under proper temperature and environmental conditions, potato starch can absorb 398 times~598 times more water than its own mass when it swells.
5. High transparency of potato starch paste
Under certain suitable conditions, the granular starch in potato paste will not be affected by expansion and gelatinization. The reason for the transparency of potato starch paste is that its chemical molecular structure formula has condensed phosphate group and no fatty acid. Phosphorus, as the most important element in potato starch molecules, exists in the form of covalent bonds in potato starch. Nearly 300 glucose groups in potato starch contain phosphate groups, and most of the balance ions on the phosphate group are organic ions,
Such as manganese ion, calcium ion, iron ion, etc., and play an irreplaceable role in the gelatinization reaction of potato starch.
The phosphate group in potato starch shows negative charge in the aqueous solution and does not combine with other substances with negative charge. It is also very important and irreplaceable in the whole crafty reaction step, resulting in the potato starch can quickly combine with the water in the solution and achieve the effect of swelling, so the viscosity of potato starch and water is increased, resulting in starch paste.
Characteristics of potato modified starch
At present, good progress has been made in the research and development of potato modified starch abroad, and a variety of potato starch and potato modified starch related products with rich varieties and good quality have been developed.
Starch derivatives obtained by changing some special physiological properties of starch through physical, chemical or enzymatic methods and making a series of changes in its function or structure are called modified starch. Common potato modified starch includes pre-gelatinized starch, hydroxyalkylated starch, cross-linked starch, esterified starch, etherified starch, etc.
The branch chain molecular weight of potato pre-gelatinized starch is larger than that of sweet potato, wheat and corn pre-gelatinized starch, so it has strong viscosity.
Agglomeration: Potato acid converted starch can be made into a series of biological films: in relatively low temperature environment, potato hydroxyalkyl starch has a certain water holding capacity and is the best raw material for making frozen pudding; Potato cross-linked starch made from potato raw starch with strong water absorption and excellent thickening can improve its shear resistance and stability.