## 1 Introduction  
Fruit is one of the richest sources of active bio-compounds among other foods and their distribution on the planet is neither equitable nor uniform. [1]. Fruit consumption is highly recommended, since through its consumption, the human body gains important vitamins, minerals, fiber, tocopherols, and polyphenols [2]. It is well known that eating habits can have an influence on the prevention of metabolic diseases such as hypertension, diabetes, and obesity. Various studies described many polyphenols compounds found in foods, such as fruit, vegetables, tea, and seeds, as having antioxidants properties [3; 4]. These polyphenol compounds are recognized to prevent damage caused by oxidative stress, such as cell and DNA damage [5; 6; 7]. Epidemiological studies revealed that there is a correlation between high consumption of phenolic compounds in the diet and reduced risks of cardiovascular diseases. Probably the main antioxidant activity that has been associated with phenols is their ability to scavenge free radicals [8]. Therefore, various techniques are being used to deliver fruit to the consumer with maximum quality. As mostly well known, fruit contains approximately 80-99% free water which makes them highly perishable. The drying process is one of the preservative methods used to extend the shelf life of fruit and better retain their nutrients by the means of reducing free water in food. The drying method is chosen based on the particularities of the product characteristics and socio-economic considerations as well as the energy need as fossil fuel prices are increasing [9]. Unfortunately, some studies pointed out the losses of some active biological compounds such as vitamin C and carotenoids [10; 11], total polyphenols contents, and total flavonoids content [12] during drying. The long drying times at relatively high temperatures during the falling rate periods mostly lead to thermal degradation of some heat sensitive fruit compounds; consequently, microwave drying uses a shortened drying time and improves the final quality of the dried products [11]. Furthermore, for conserving some components of fruit, thermolabile, some techniques, such as drying using microwaves and freeze-drying, have been developed with the aim of offering products with extended storage stability and adequate convenience for the consumer while reducing the nutrients losses. Freeze-drying, also known as lyophilization, is among the best drying techniques used for producing better quality of dried and solid foods. It is a preferred method for drying foods containing high heat sensitivity and oxidation-prone compounds, since it operates at very low temperatures and under high vacuum [13]. The application of freeze drying to various fruit and vegetables, such as lemon, apple, guava, strawberry, blackberry, pumpkin, tomato, asparagus, coffee, tea, garlic, ginger, maple syrup, etc., has already been reported in the literature [14; 15; 16; 17]. Compared to freeze drying, the microwave drying system caused some reductions on one hand, and the increase of some bioactive compounds on the other hand, as reported also by [18; 19; 20; 21; 22]. Distinct mathematical models describing the drying process have been proposed to optimize the process and the set up the effective dryers. Moreover, the prediction of drying rates for distinct dryers and moisture diffusion parameters of fruit products are important components of microwave drying simulation models and are essential for an efficient moisture transfer analysis [23]. At present, there is no study that investigated the effect of a drying method on the bioactive compounds of tree tomatoes, which are a good source of polyphenols, vitamin C, flavonoids, carotenoids, anthocyanin, and also exhibit associated antioxidant capacity as per DPPH and FRAP [4; 24; 25].