Method of Restoring and Maintaining the Texture of Tapioca Pearls as Just Cooked after Retrogradation

Abstract

The present invention relates to a method of storing and transporting cooked tapioca pearls in edible oil at low temperature (0° F. to 41° F.). Even though retrogradation happens under these conditions, the texture of tapioca pearls can be restored like just cooked by reheating in the oil to above starch gel temperature. The restored texture of tapioca pearls can be kept unchanged as long as the temperature is above their gel temperature.

Claims

1. A method of storing and transporting cooked tapioca pearls in oil at low temperature for a long period (0° F. for up to a year or 32-40° F. for up to seven days) even though retrogradation happens under these conditions. And the subsequent restoration of the tapioca pearls texture to be like just cooked by reheating the retrograded tapioca pearls in the oil to above starch gel temperature (between 150° F. and 211° F., preferably between 150-170° F. The restored texture of tapioca pearls can be kept unchanged as long as the temperature is above their gel temperature.

2. The method of claim 1, wherein said the edible oil includes but not limited to vegetable oil, canola oil, corn oil, sunflower oil, salad oil, olive oil, coconut oil, almond oil, soy bean oil or animal-based oil, such as butter, animal fat oil etc.

3. The method of claim 1, wherein said the edible tapioca pearls (tapioca pearls) are made of native starch or chemically modified starch with or without additives. Native starches include but not limited to tapioca starch, potato starch, corn starch, taro starch, rice starch, waxy rice starch, waxy corn starch, waxy barley starch etc. Chemically modified starches include but not limited to those with E numbers from E1400-E1450. The additives include polysaccharide, caramel color, brown sugar, emulsifier, stabilizer and preservers. The polysaccharides include but not limited to an oligosaccharide, dextrin, carrageenin, pectin, locust bean gum, guar gum, tamarind tum and xanthane gum. Emulsifiers and stabilizers include but not limited to those with E number from E400-E499. The preservatives include but not limited to those with E number from E200-E299.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0008] For boba tea businesses, emphasizing the cooking of tapioca pearls can improve the efficiency, reduce the cost, and simplify the retail operation. However, no widely accepted ready to serve cooked tapioca pearls are available. This invention develops a method that is suitable for preparing, cooking and storing tapioca pearls in a centralized facility and ready for use in retail stores with a simple procedure. In this method, the cooked tapioca pearls are cooled and stored at 0° F. or 32-40° F. The cooked tapioca pearls may be dispersed in oil before or after being cooled down or frozen. The product will be stored and transported at these temperatures. Retrogradation happens during these procedures, but our method of reheating them in oil to above gel temperature can effectively restore their texture with no difference as just after they have been cooked. As long as the product is kept above the gel temperature, it will not show any sign of retrogradation or swelling. Traditionally, when the tapioca pearls are kept in sugar syrups, as a starch gel, it will absorb more water and the tapioca pearls will swell. This swelling accelerates at high temperature. For not long, the tapioca pearls swell and become too soft. In this invention, we find that replacing the aqueous sugar solution with an edible oil, the swell disappeared, and the cooked tapioca pearls can keep the softness and chewiness as long as the temperature is above gel temperature. In this period, the cooked tapioca pearls can be used right away, thus simplify the operation. An additional benefit of using the method mentioned in this invention is the tapioca pearls will not stick together easily due to existing of a thin oil film between them and can be easily separated in contrast to those being kept in aqueous sugar solutions.

[0009] The edible oils mentioned here include any vegetable base oil or the mixture of them, such as normal vegetable oil, canola oil, corn oil, sunflower oil, salad oil, olive oil, coconut oil, almond oil, soy bean oil, to name a few or animal-based oil, such as butter, animal fat oil,

[0010] This method can be applied to tapioca pearls used in any beverages, although only boba tea is mentioned here. The tapioca pearls may be made from native starch, chemically modified starch, including crosslinked starch with or without additives, such as hydrocolloids, emulsifier and stabilizer, enzymes, caramel color, brown sugar, sugar syrup, to name a few.

EXAMPLE 1

[0011] Tapioca pearls made of native tapioca starch were cooked in boiling water for 30 minutes and kept at 140-211° F., preferably at 150-170° F. for 30 min. Then were rinsed with cold water. The excess water was drained and the tapioca pearls were poured into a container filled with vegetable oil, which was then kept in a refrigerator or a freezer. Before use, the tapioca pearls in oil were reheated to 140-211° F., preferably 150-170° F. to bring the temperature of the tapioca pearls above their gel temperature and then kept at this temperature before being consumed. When serving, the oil was drained while the other ingredients were prepared. Then the tapioca pearls were lightly rinsed with water to remove the oil residue and added to the beverage.

EXAMPLE 2

[0012] Commercially available tapioca pearls made with a mixture of native and modified starch (for example, E-Fa Brand black tapioca pearl), were boiled in water for 5-10 minutes and then kept at 140-211° F., preferably at 150-170° F. for 15-30 minutes, rinsed with water and stored in vegetable oil after draining the water. The tapioca pearls in oil were stored in a freezer. The frozen tapioca pearls were then reheated to 140-211° F., preferably 150-170° F. for 30-60 min, preferably 45-60 min to bring the tapioca pearls above gel temperature and kept at this temperature before serving. When an order comes in, measure one cup of tapioca pearls and drain the oil when preparing other ingredients. The tapioca pearls were rinsed by water to remove the oil residue before adding to the drink mixture. The tapioca pearls kept in oil at 150-170° F. has no detectable change on texture or swelling for at least three days.

EXAMPLE 3

[0013] The above-mentioned tapioca pearls were cooked, cooled and frozen immediately. They were then mixed with shorting oil and transported to the storefront. Before use, they were heated to above gel temperature and kept at this temp before served. No observable change of texture of the tapioca pearls were found for at least three days.