How to dry vegetables and fruits, you must understand clearly

You will not be able to do a good job when you have to do too many things at the same time, in the field of production and business, wanting to make too many products will not make any good products. This is the problem of many customers today, wanting to do many things, drying many types of products but not knowing exactly what they want to do. A very general question, I want to buy a dryer for all kinds of vegetables and fruits, to choose the right dryer, it is necessary to be detailed and focus on some specific types of finished products.

I temporarily divide into 2 purposes of use when buying a dryer, including family use and business production use.

I. For family use, there are many drying products, not focusing on any product, you can dry whatever you like, dry crispy, dry soft…dry vegetables, medicinal herbs, dried meat, cereal grains. Usually for such drying purposes, choosing a multi-function dryer is the right function, common drying, drying many types of products, drying temperature range 35 ~ 95^oC or up to 160oC with the requirement of drying crispy cereals. The drying principle of this dryer is to use hot air to blow in a forced circulation in the drying chamber to evaporate the water in the product, the steam is blown out to dry the product in the drying chamber. The higher the drying temperature, the more water evaporates, the faster the product dries, depending on each type of drying product, we choose the appropriate drying temperature.

II. For the purpose of production and business, we need to focus on each specific group of drying products to easily choose the right specialized dryer. For example, convection dryers usually dry what products, cold dryers are good for which product groups, and freeze dryers also need to be applied to the right drying products to achieve high efficiency. Please see the DRYER COMPARISON section to better understand the products that need to be dried.

Currently, there are many groups of product dryers that we need to clearly distinguish, 1 is hot air circulating dryer, 2 is cold dryer and 3 is freeze dryer. Specifically as follows:

1. Circulating hot air dryer: the drying chamber is blown with hot air circulating with the drying temperature adjustable from 35 ~ 95^oC or 35 ~ 160^oC, this is the most popular group of dryers because the cost of purchasing the machine is the most suitable, the lowest, and meets the drying needs of the most products.

The characteristics of heat drying depend on each group of dried products such as vegetables, fruits, medicinal plants, leaves, flowers, powder, dried meat … will give different characteristics. For example, drying vegetables, drying leaves, drying flowers … (products without sugar, fat) can be dried to the point of being crushed into powder, drying fruits is dried like dried banana, dried jackfruit, dried mango, dried jam, … Drying meat like dried beef, dried pork, dried buffalo … then the dried product is tough, dry …

Many customers only ask one type of question: can this machine dry crispy or just soft, we always divide it into each type of product, drying vegetables, herbal leaves, drying flowers, drying products without sugar, fat, honey… can dry crispy. As for products with sugar, fat such as ripe fruits, candied jam, animal meat, can only dry soft, cannot dry crispy like crispy jackfruit, crispy banana. That is the characteristic of each group of dried products in reality.

2. Cold dryer, also known as heat pump dryer: this is a group of dryers used for more specialized products, thin products, volatile, need to be dried at low temperature to keep color, flavor, nutrition. The drying temperature is usually 15 ~ 60^oC and the drying principle is to use dry wind to circulate in the drying chamber, the difference with hot drying here is to use dry wind, that is, to separate moisture, and the wind circulates in a closed chamber, only condensed water is led out through the water pipe. Typical cold-dried products such as drying flowers for tea, drying herbal leaves, drying mushrooms, drying dried fruit, drying jam, pills… dried products have higher value than hot-dried products, keep the color more beautiful, keep the flavor and nutrition better.

The structural characteristics of freeze-dried and hot-dried products are similar. Drying vegetables, plants, leaves, and flowers can all be dried into crispy powder, while drying ripe fruits, dried meat, candied jams, etc. can all be dried into soft pieces.

3. Freeze dryer: it can be said that all freeze-dried products from vegetables, fruits, animal meat, medicinal herbs, powder solutions, yeast, tubers… are freeze-dried to have the characteristics of being dry, crispy, and can be crushed easily. Although freeze-dried products are dry and crispy, they are usually only applied to typical products with high value on the market such as dried cordyceps mushrooms, golden flower tea, dried durian segments, strawberries, lotus tea, probiotics, spirulina powder, crispy dried fruits… all have the common characteristics of being dry, crispy, spongy, and retaining their natural shape and color…

Freeze drying is drying the product in the drying temperature range from -40^oC (negative temperature) to 60^oC (positive temperature) and drying in a vacuum chamber. During the drying process from beginning to end, the temperature on the product will change in a V shape: that is, from 30^oC (positive temperature) to -40^oC (negative temperature) and then increase to 40 ~ 60^oC (positive temperature). I have to write negative and positive temperature clearly like this because many users do not understand this issue.

Many CUSTOMERS need to find a dryer but do not specify what product they want to dry, they want to do everything, so when searching for a dryer it will be very vague, buying the wrong machine is normal. Therefore, it is necessary to clearly understand the characteristics of the finished product to be made, for example, crispy jackfruit, crispy banana, crispy sweet potato that we often buy to eat at a cheap price, that is crispy fried fruit, it is necessary to distinguish between crispy drying and crispy frying.

In conclusion, if you cannot clearly understand how to choose the right fruit and vegetable dryer, then find the right type of product you want to make, or a similar type available on the market, find the image on google and send it to us to easily advise the right type of dryer to use.