CN105135824A - Lepidium meyenii walp temperature-varied drying method - Google Patents

Abstract

The invention discloses a temperature-variable drying method for maca, which belongs to the technical field of primary processing of agricultural products; the method of the invention mainly includes the following steps: draining fresh maca after washing and drying at room temperature; Compared with the traditional drying method, the invention uses hot air drying equipment and adopts a slow variable speed heating process from low temperature to high temperature, which avoids the rapid loss of maca water, reduces deformation, maintains color, and ensures that nutrients are not lost. The drying time of maca has been shortened by more than 20 days, and the drying efficiency has been significantly improved. At the same time, it has also avoided the defects of traditional sun-drying methods such as labor-intensive, large-scale occupation, and easy pollution.

Description

A kind of variable temperature drying method of Maca

technical field

The invention discloses a variable temperature drying method for maca, which belongs to the technical field of primary processing of agricultural products.

Background technique

Maca ( Lepidium meyenii ) belongs to the genus Lepidium of the Brassicaceae family. It is also known as beetroot or Peruvian ginseng. It is a plant with both medicinal and edible uses. It has the effects of enhancing physical strength, enhancing human immunity, anti-fatigue, and improving fertility. In 2011, maca powder was officially approved as a new resource food by the former Ministry of Health. More than 60% of China's maca planting bases are concentrated in Lijiang. The annual planting area and output of maca in this area reach 175hm ² and 780t respectively, accounting for 90% and 93% of the country's total. In 2014, the output value of maca in Lijiang was close to 4 billion , has become an important source of income for local farmers.

At present, maca generally adopts the drying method of drying in the sun. The process is harvesting→cleaning→trimming and removing hair roots (in some areas, slice the roots)→natural drying. This drying method is simple to operate and low in cost, but there are many deficiencies. First of all, it takes a long time, usually more than 30 days, the production efficiency is low, and the labor load is large. Second, poor sanitation. It is difficult to prevent insects, rats, dust and other pollution in drying places such as drying sheds, drying yards and even courtyards. Thirdly, natural sun-dried maca is affected by air temperature and humidity in different places, and its appearance and internal quality vary greatly. Therefore, the introduction of drying equipment with high efficiency, easy operation, and low investment and the establishment of a suitable drying process are extremely important for saving costs and increasing efficiency for maca drying.

The invention processes the fresh maca into a dry product by utilizing room temperature draining and variable temperature drying techniques.

Contents of the invention

The object of the present invention is to provide a method for drying maca with variable temperature, which uses variable temperature drying technology to process fresh maca into dry products, greatly shortens the processing time, and prevents the pollution of insects, rats, dust, etc.

The purpose of the present invention is achieved through the following technical solutions:

(1) Place the washed fresh Maca at room temperature and drain naturally until there is no moisture on the surface;

(2) The maca obtained in step (1) is dried by a variable temperature drying method until the moisture content is ≤13%.

The specific process of the variable temperature drying method is that the initial drying temperature is 20-30°C, and after the temperature is maintained for 30-40h, the temperature is uniformly raised to 55°C at a heating rate of 2.5-5°C/24h, and then the temperature is increased to 5-10°C. After the temperature is evenly raised to 65-70°C at a speed of /12h, keep warm until the moisture content of maca is ≤13%.

The beneficial effects of the present invention are:

(1) Compared with the traditional air-drying method, the maca drying method of the present invention adopts a variable temperature drying method, and the drying temperature is from low to high, and the temperature rises slowly; the low temperature in the early stage of drying avoids the rapid loss of maca moisture, thereby reducing the maca skin. The degree of wrinkle, the high temperature in the later stage of drying reduces the degradation of nutrients;

(2) The Maca drying method of the present invention shortens the time by more than 20 days compared with the traditional drying method;

(3) The dried maca by the method of the present invention not only ensures its appearance and internal quality, but also avoids the disadvantages of the traditional method, such as labor-intensive, large space occupation, and easy pollution.

Description of drawings

Fig. 1 is the Maca variable temperature drying time-temperature curve of embodiment 1;

Fig. 2 is embodiment 1 maca dry basis moisture content curve;

Fig. 3 is the form after embodiment 1 yellow maca is dried at variable temperature;

Fig. 4 is the moisture content curve of embodiment 2 purple maca dry basis;

Fig. 5 is the morphology after embodiment 2 purple maca is dried at variable temperature;

Fig. 6 is embodiment 3 black maca dry basis moisture content curves;

Fig. 7 is the morphology of the black maca in Example 3 after variable temperature drying.

Detailed ways

The substantive features and remarkable progress of the present invention are further described below through the examples and accompanying drawings, but the protection scope of the present invention is not limited to the examples.

Example 1

Wash the fresh yellow maca, place it at room temperature and drain it naturally until there is no moisture on the surface; then place the Chinese medicinal materials in a hot air drying oven to dry; the process parameters are as follows: stabilize the temperature for 40 hours at an initial temperature of 30°C Afterwards, uniformly heat up to 55°C at a heating rate of 5°C/24h, then uniformly heat up to 70°C at a rate of 10°C/12h, keep warm until dry, and the time to reach a moisture content of ≤13% is 130h. After drying, the surface of maca is smooth without wrinkles, the overall deformation is small, and its apparent color is bright (see Figures 1, 2, and 3).

Example 2

Wash the fresh purple maca, place it at room temperature and drain it naturally until there is no moisture on the surface; then dry it in a Chinese herbal medicine dryer; the process parameters are, after the initial temperature is 25°C , according to the heating rate of 3 ℃ / 24h uniform heating to 55 ℃, and then 7.5 ℃ / 12h speed uniform heating to 65 ℃, heat preservation until dry, the time to reach moisture content ≤ 13% is 118h. After drying, maca is bright in color, smooth and wrinkle-free, and the overall deformation is small (see Figures 4 and 5).

Example 3

Wash the fresh black maca, place it at room temperature and drain it naturally until there is no moisture on the surface; then dry it in a Chinese herbal medicine dryer; , according to the heating rate of 2.5 ℃ / 24h uniform heating to 55 ℃, and then 5 ℃ / 12h speed uniform heating to 68 ℃, heat preservation until dry, the time to reach the moisture content ≤ 13% is 123h. After drying, the appearance of maca is better, the surface is smooth and wrinkle-free, and the overall deformation is small (see Figures 6 and 7).

The nutrient content of yellow, purple and black maca under variable temperature drying process is shown in Table 1;

Table 1 The contents of various nutrients in maca of each color under variable temperature drying process (%)

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Claims (2)

1. an agate coffee alternating temperature drying means, is characterized in that following aspect:

(1) naturally drain to surface without moisture under the fresh agate coffee cleaned being positioned over room temperature;

(2) the agate coffee obtained in step (1) is carried out drying by alternating temperature drying mode, until reach moisture content≤13%.

2. agate coffee alternating temperature drying means according to claim 1, it is characterized in that: in step (2), the detailed process of alternating temperature drying is dry initial temperature is 20-30 DEG C, after this temperature keeps 30-40h, by the programming rate of 2.5-5 DEG C/24h, evenly be warming up to 55 DEG C, after being evenly warming up to 65-70 DEG C with the speed of 5-10 DEG C/12h again, insulation is until agate coffee moisture content≤13%.