蜡质玉米淀粉的特性及用途介绍

颗粒形状和大小：

Particle shape and size:

蜡质玉米颗粒的形状多为多角形，此外，还有圆形，其表面较为粗糙，无裂纹；普通玉米淀粉颗粒表面光滑，多为多角形；马铃薯淀粉颗粒多为卵形，表面光滑、颗粒完整；甘薯淀粉颗粒形状多为圆形，此外还有多角形，表面光滑，无裂纹。其粒径如表1所示：

The shape of waxy corn granules is mostly polygonal, and in addition, they are also round, with a rough surface and no cracks; The surface of ordinary corn starch granules is smooth and mostly polygonal; Potato starch granules are mostly oval shaped, with a smooth surface and intact granules; Sweet potato starch granules are mostly circular in shape, in addition to being polygonal, with a smooth surface and no cracks. Its particle size is shown in Table 1:

透明度的凝沉性：

The coagulation of transparency:

淀粉糊的透明度是食品加工上的重要品质因素之一，和老化度也有很大的相关性。一般易老化者透明度较差。例如，普通玉米淀粉呈半透明白色糊，马铃薯淀粉糊和蜡质玉米淀粉则非常透明。目前常用透光度来反应淀粉糊透明度的高低，从而显示其与水结合能力的强弱。一般来说，蜡质玉米淀粉的透光率要好于马铃薯淀粉和普通玉米淀粉。

The transparency of starch paste is one of the important quality factors in food processing, and it is also closely related to aging degree. Generally, people who are prone to aging have poor transparency. For example, regular corn starch appears as a semi transparent white paste, while potato starch paste and waxy corn starch are very transparent. At present, transparency is commonly used to reflect the transparency of starch paste, thereby demonstrating its ability to bind with water. Generally speaking, the transparency of waxy corn starch is better than that of potato starch and regular corn starch.

淀粉受热，其颗粒吸水膨胀、破裂而发生糊化，在冷却过程中，淀粉分子进行重排，分子链之间以氢键结合，使淀粉分子脱水收缩，其粘附性能下降，保水性减弱。沉降体积越小，表示该淀粉越易凝沉。一般来说普通淀粉的凝沉性很强，而蜡质玉米淀粉和马铃薯淀粉的凝沉性很低，这是因为直链淀粉呈链状结构，在溶液中空间障碍小，易于取向，故易回生，尤其是中等长度的直链淀粉易回生，而马铃薯淀粉中直链淀粉的链较长，取向困难，回生慢。蜡质玉米淀粉中基本是直链淀粉，支链淀粉呈树状结构，在溶液中空间障碍大，不易取向，故不易凝沉。

When starch is heated, its particles absorb water, expand and rupture, resulting in gelatinization. During the cooling process, starch molecules rearrange, and hydrogen bonds bind between molecular chains, causing starch molecules to dehydrate and contract, resulting in a decrease in adhesive properties and weakened water retention. The smaller the sedimentation volume, the easier it is for the starch to coagulate. Generally speaking, ordinary starch has strong retrogradation, while waxy corn starch and potato starch have low retrogradation. This is because linear starch has a chain like structure, with small spatial barriers in solution and easy orientation, making it easy to retrogradation, especially for medium length linear starch. However, in potato starch, linear starch has longer chains, difficult orientation, and slow retrogradation. Waxy corn starch is mainly composed of straight chain starch and branched chain starch with a tree like structure. It has large spatial barriers in solution and is not easy to orient, so it is not easy to coagulate.

膨润力和溶解度

Swelling power and solubility

淀粉加水分散后，一旦受热会吸水膨胀形成糊状，这种糊化现象由于淀粉种类的不同而有差异。一般来说，马铃薯淀粉的糊化温度低，但吸水膨润速率；而普通玉米淀粉恰恰相反。马铃薯淀粉在60-60℃低温下的吸水膨润力可达70%以上，而蜡质玉米淀粉于68-85℃间的膨润力急速增加。普通玉米淀粉则需到90℃以上的高温才有25%的膨润力。

After starch is dispersed with water, once heated, it will absorb water and expand to form a paste, which varies depending on the type of starch. Generally speaking, potato starch has a low gelatinization temperature but a high water absorption and swelling rate; However, ordinary corn starch is the opposite. The water absorption and swelling power of potato starch can reach over 70% at low temperatures of 60-60 ℃, while the swelling power of waxy corn starch increases rapidly between 68-85 ℃. Ordinary corn starch requires a high temperature above 90 ℃ to have 25% swelling power.

糊黏度性质

Paste viscosity properties

相同浓度下，蜡质玉米淀粉糊液的黏性比马铃薯低，但高于普通玉米淀粉。

At the same concentration, the viscosity of waxy corn starch paste is lower than that of potatoes, but higher than that of ordinary corn starch.

蜡质玉米淀粉乳在PH接近中性时，糊的黏度较高且比较稳定，在较高的PH或较低的PH小，糊的黏度稳定性差。说明蜡质玉米淀粉糊的抗酸碱能力差。

Wax corn starch emulsion has a high and stable viscosity when its pH is close to neutral, but its viscosity stability is poor when its pH is high or low. The waxy corn starch paste has poor acid and alkali resistance.

在食品制造过程中常加入糖品，使用在其中的淀粉会受到其中糖品的影响。由于蔗糖分子中有多个羟基极易溶于水，糖溶于淀粉乳中，相对地减少了淀粉糊膨胀糊化的水分，使淀粉犹如在比较少的水中糊化，颗粒膨胀困难，难以糊化，故糊化温度升高，黏度也随时增大。随着蔗糖用量的增加，对淀粉颗粒膨胀和糊化的抑制作用增强，黏度达到一定极限后也随之下降。

Sugar is often added in the food manufacturing process, and the starch used in it will be affected by the sugar content. Due to the presence of multiple hydroxyl groups in sucrose molecules that are highly soluble in water, sugar dissolves in starch milk, which relatively reduces the amount of water needed for starch paste to expand and gelatinize. This makes starch gelatinize as if it were in relatively little water, making it difficult for the particles to expand and gelatinize. As a result, the gelatinization temperature increases and the viscosity also increases at any time. With the increase of sucrose dosage, the inhibitory effect on starch particle expansion and gelatinization is enhanced, and the viscosity also decreases after reaching a certain limit.

氯化钠的存在使蜡质玉米淀粉的糊化温度有所提高。食盐与蔗糖一样，会降低水分活度，影响淀粉分子与水分子的作用，阻碍淀粉的糊化性能，食盐的量越大，淀粉越难糊化，淀粉糊凝沉更快。

The presence of sodium chloride increases the gelatinization temperature of waxy corn starch. Salt, like sucrose, can reduce water activity, affect the interaction between starch molecules and water molecules, and hinder the gelatinization performance of starch. The larger the amount of salt, the harder it is for starch to gelatinize, and the faster the starch paste settles.