A method for processing roasted sweet potatoes

Abstract

This invention discloses a processing method for roasted sweet potatoes, belonging to the field of sweet potato processing technology. The method involves first placing the sweet potato at a suitable temperature for amylase activity, promoting the saccharification process and increasing its sweetness; simultaneously, allowing it to stand at a low temperature for an extended period allows the fructose inside to convert from furanose to pyranose, significantly increasing the sweetness; after roasting the sweet potato at high temperature, the surface is made sticky by lowering the temperature and increasing humidity, achieving a "sugar return" effect; finally, high-temperature treatment removes excess moisture, further enhancing the sweetness; and finally, vacuum packaging with nitrogen gas and low-temperature storage yields roasted sweet potatoes, effectively extending the shelf life of cooked sweet potatoes.

Description

Technical Field

[0001] This invention relates to the field of sweet potato processing technology, specifically a method for processing roasted sweet potatoes. Background Technology

[0002] Sweet potatoes are rich in protein, starch, pectin, cellulose, amino acids, vitamins, and various minerals, and have benefits such as protecting the heart, preventing emphysema, diabetes, and aiding weight loss. Current processing methods for sweet potatoes mainly involve baking or high-temperature steaming / boiling. However, baking or steaming primarily cooks the sweet potatoes, causing the starch inside to gelatinize at high temperatures, making the starch easier to digest and absorb. It doesn't significantly increase the sweetness of the sweet potato, and cooked sweet potatoes cannot be stored for long periods.

[0003] To make sweet potatoes sweeter, the saccharification process needs to be improved. Currently, the main method to increase sweetness is to store the sweet potatoes for an extended period, allowing the starch in the sweet potatoes to be converted into sugar by amylase. However, prolonged storage easily leads to rotting, and starch saccharification requires the participation of amylase, which is most active at around 60°C. Therefore, prolonged storage is not ideal for sweet potato saccharification.

[0004] Therefore, in order to fully enhance the sweetness of sweet potatoes after they have ripened, and at the same time enable them to be preserved for a long time, we have developed a processing method for roasted sweet potatoes based on years of practical experiments. This method can significantly increase the sweetness of the ripened sweet potatoes while also allowing them to be preserved for a long time at low temperatures. Summary of the Invention

[0005] The purpose of this invention is to provide a processing method for roasted sweet potatoes to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for processing roasted sweet potatoes includes the following steps: 1) Wash the fresh sweet potatoes and set aside; 2) Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% for 6-7 days; 3) Lower the ambient temperature around the sweet potatoes to 8℃-13℃ and leave them for 60 days; 4) Raise the ambient temperature around the sweet potatoes to 40℃-45℃ again and leave them for 6-7 days; 5) Place the sweet potatoes in an environment with a temperature of 110℃-120℃ and bake for 30 minutes; 6) Raise the ambient temperature around the sweet potatoes to 180℃-190℃ and bake for 60 minutes; 7) Lower the ambient temperature around the sweet potatoes to 70℃-80℃ and bake for 30-60 minutes; 8) Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% and let them cool for 6-7 days until the surface of the sweet potatoes becomes sticky; 9) Place the sweet potatoes in an environment with a temperature of 90℃-100℃ and bake for 50-60 minutes; 10) Place the sweet potatoes in a cool, ventilated place at room temperature for 1-2 days; 11) Pack the sweet potatoes, vacuum them, fill them with nitrogen, and store them in an environment of 18℃-25℃.

[0007] Compared with the prior art, the beneficial effects of the present invention are: This processing method initially involves placing the sweet potato at a suitable temperature for amylase activity, promoting the saccharification process and increasing its sweetness. Simultaneously, prolonged static placement at low temperatures allows the fructose inside to convert from furanose to pyranose, significantly enhancing sweetness. After high-temperature baking to cook the sweet potato, the surface is made sticky by lowering the temperature and increasing humidity, achieving a "sugar return" effect. Finally, high-temperature treatment removes excess moisture, further increasing sweetness. Finally, vacuum packaging with nitrogen purging and low-temperature storage yields roasted iced sweet potatoes, effectively extending their shelf life after cooking. Detailed Implementation

[0008] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0009] This embodiment provides a method for processing roasted sweet potatoes, which includes the following steps: 1) Wash the fresh sweet potatoes and set aside; 2) Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% for 6-7 days. This allows the sweet potatoes to be at the appropriate temperature for the amylase to be active, which accelerates the conversion of internal starch into monosaccharides such as glucose. This promotes the saccharification process inside the sweet potatoes, making them sweeter and more glutinous after they are cooked, thus increasing their sweetness. 3) Lower the ambient temperature of the sweet potato to 8℃-13℃ and leave it for 60 days. The long-term static placement of the sweet potato in a low-temperature environment can convert the fructose inside it from furan to pyran, which can greatly increase the sweetness of the sweet potato. 4) Raise the ambient temperature around the sweet potatoes to 40℃-45℃ again and leave them for 6-7 days. By repeatedly raising and lowering the temperature, the activity of amylase is increased again, which further converts the unconverted starch inside the sweet potatoes into sugar, thereby further improving the saccharification effect. 5) Place the sweet potatoes in an environment with a temperature of 110℃-120℃ and bake for 30 minutes; 6) Raise the ambient temperature around the sweet potatoes to 180℃-190℃ and bake for 60 minutes; use a gradual heating method to ensure that the sweet potatoes are heated evenly, accelerate the gelatinization of the internal starch, and improve the ripening process of the sweet potatoes. 7) Lower the ambient temperature around the sweet potatoes to 70℃-80℃ and bake for 30-60 minutes. After baking, cool down again to further cook the parts of the sweet potatoes that are not fully cooked, making them softer and sweeter. 8) Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% for 6-7 days to cool them. This will make the surface of the sweet potatoes sticky and release sugar, thus achieving the process of sugar and honey returning to the sweet potatoes. 9) Place the sweet potatoes in an environment with a temperature of 90℃-100℃ and bake for 50-60 minutes to allow the moisture in the sweet potatoes to evaporate and the sugar on the surface of the sweet potatoes to solidify. 10) Place the sweet potatoes in a cool, ventilated place at room temperature for 1-2 days to allow them to cool down and prevent them from freezing after being packed into boxes; 11) Pack the sweet potatoes, vacuum-seal them, fill them with nitrogen, and store them in an environment of 18℃-25℃. When using, simply tear open the packaging and eat or heat them before consumption.

[0010] This invention significantly improves the sweetness of sweet potatoes while extending their shelf life through ultra-low temperature nitrogen preservation, thus making up for the "shortcoming" in the supply of sweet potatoes in the summer market. It is of great significance to pioneer the field of high-end sweet potato deep processing in China and has broad market prospects.

[0011] It should be noted that the above embodiments are only specific and clear descriptions of the technical solutions and features of this application. Solutions or features that are prior art or common knowledge to those skilled in the art will not be described in detail in the above embodiments.

[0012] Furthermore, the technical solutions of this application are not limited to the above embodiments. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method of processing baked sweet potato characterized by comprising the steps of, Includes the following steps: Wash the fresh sweet potatoes and set them aside. Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% for 6-7 days; Lower the ambient temperature around the sweet potatoes to 8℃-13℃ and leave them for 60 days; Raise the ambient temperature around the sweet potatoes to 40℃-45℃ again and leave them for 6-7 days; Place the sweet potatoes in an environment with a temperature of 110℃-120℃ and bake for 30 minutes; Raise the ambient temperature around the sweet potatoes to 180℃-190℃ and bake for 60 minutes; Lower the ambient temperature around the sweet potatoes to 70℃-80℃ and bake for 30-60 minutes. Place the sweet potatoes in an environment with a temperature of 50℃-55℃ and a humidity of 85%-90% and let them cool for 6-7 days until the surface of the sweet potatoes becomes sticky. Place the sweet potatoes in an environment with a temperature of 90℃-100℃ and bake for 50-60 minutes; Place the sweet potatoes in a cool, ventilated place at room temperature for 1-2 days. Pack the sweet potatoes, vacuum them, fill them with nitrogen, and store them in an environment of 18℃-25℃.