5. Applications of Mulberry in the Food Industry
Epidemiological studies suggest the role of oxidative stress in the generation and propagation of many chronic diseases. Therefore, to counteract the unwanted effects of oxidative stress exogenous antioxidants in the form of dietary supplements or even functional foods are necessary for the human body
[21].
Black mulberry fruits are considered functional foods that, when ripe, have a black–purple color and can be eaten fresh or dehydrated
[27][28][29]. Baked mulberries are very perishable fruits, mainly due to their smooth texture, high softening and breathing rate, and susceptibility to fungal attacks. After harvesting, their aroma and appearance change, decomposition processes increase, and synthesis processes are reduced in intensity, which is why an optimal method of preservation is recommended
[28][30]. In order to satisfy the requirements of consumers by ensuring that products are both healthy and delicious, and since mulberries are famous all over the world, they have started to be processed in different forms, so that they can be stored and consumed in the long term
[28][31][32]. Due to the anthocyanin pigments responsible for their dark color, mulberry fruits are also used as color or flavor additives in the food industry for the production of healthy foods without synthetic food additives
[27][32].
In recent years, the
Morus plant species began to occupy an important position in the food industry, due to its health benefits. Recently, various mulberry-based foods were developed and marketed in Asian regions
[22]. As a food, in addition to being consumed fresh, but also dried, mulberry is suitable for the preparation of several foods, such as juices, syrups, wine, vinegar, brandy, jellies, marmalades or jams
[7][23].
Mulberry fruits can be eaten ripe or can be found in the market in various forms as nutritional supplements, as a tonic and sedative. The only official medicinal product in the British Pharmacopoeia is
Siropus mori, used mainly as an adjunct to its slightly laxative and expectorant qualities
[33][34][35].
The water-soluble anthocyanin pigments responsible for the color of mulberry fruits are also used as color or flavoring additives in the food industry, a practice increasingly used to create foods that contain natural additives
[27][32].
Taking into account the requirements of consumers, the nutritional value and bioactive compounds that provide a number of beneficial effects on the human body, the mulberry plant is becoming increasingly studied or even exploited for the production of food or food supplements. It is also used as a main ingredient in the production of foods, such as jams
[36], lollipops and jellies
[37], wines
[38][39], syrups
[40] and other functional beverages and foods
[41][42][43][44][45][46] (
Table 1).
Table 1.
Product foodstuffs, their compositions and health benefits (2016–2021).
Product Foodstuff |
Major Findings |
Reference |
Black mulberry food colorants |
Three formulations of solid natural colorants based on black mulberry anthocyanins (cyanidin-3-O-glucoside and cyanidin-O-rhamnoside), obtained through the spray-drying technique, were developed. These natural additives have a good stability in time and a variation of anthocyanin content and color parameters during the 12 weeks of storage, at room and refrigerated temperatures. |
[32] |
Mulberry gummy candies |
Gummy candies obtained from 5, 7.5 and 10 g of mulberry molasses/100 g gelatin illustrate the potential for using molasses in a healthier development of confectionery products. These candies contain natural sugars, thus replacing sugar syrup or artificial sweeteners. |
[37] |
The mulberry plant is also used in the form of food supplements. In recent years, a number of patents (
Table 2) were developed based on mulberry with various functional and therapeutic applications.
Mulberry fruits possess a lower pectin content than other fruits used in the manufacture of jams. There is a patent (RO 135033 A2) that implements different processes for obtaining jams from black, white or red mulberry fruit by gelling with the addition of pectin
[48]. An ethnobotanical study conducted by Li et al., 2017, on white mulberry leaf tea, showed that teas could be included in the category of functional foods, having a detoxifying effect, treating coughs and sore throats, colds, etc.
[49]. Lin et al., 2020
[47], confirmed that drinks obtained from mulberry leaves are functional products that prevent diseases related to aging and Meng et al., 2020, mention that white mulberry leaf tea is used in Asian countries in order to control diabetes
[50].
Table 2.
List of patents based on the therapeutic and functional applications of
Morus
(2017–2021).
Application No. |
Species/Part |
Sample Type |
Results/Mechanism |
Ref. |
US 11,090,349 B2 |
Morus alba L.; Morus alba var. multicaulis L.; Morus nigra; Morus australis Poir. |
Raw material,
dry leaves |
Inhibits α-glucosidase. It has the ability to control blood glucose levels and reduce melanin production for the treatment of conditions caused by pigmentation, such as freckles, chloasma, striae gravidarum, sensitive plaque and melanoma. |
[51] |
AU 2019201188 B2 |
M. alba root bark; acacia barks; Uncaria gambir, leaves; Curcuma longa L. |
Mixture extract |
The compound mixture, demonstrated beneficial synergistic effects with improved anti-inflammatory and anti-nociceptive efficacy, but also the attenuation of joint stiffness. |
[52] |
Mulberry leaf powder drink |
The effect on adults of consuming of biscuits with a beverage of powdered mulberry leaves in the afternoon on postprandial glucose levels at dinner was a significant reduction in postprandial increases in glucose. |
[42] |
US 10,588,927 B2 |
Mulberry (M. alba) and poria cocos peel |
Mixed extract |
Used either as a food product or as a pharmaceutical composition with the aim of preventing or treating degenerative neurological diseases, having the ability to improve memory and protection on neurons. |
[53] |
Mulberry leaf tea |
The quercetin 3-O-malonylglucoside and kaempferol 3-O-malonylglucoside found in white mulberry leaves can be used as ingredients for a functional food to improve the health benefits, such as controlling blood glucose, preventing aging-related diseases and regulating glycolipid metabolic abnormalities. |
[43 |
US 2020/0360457 A1 |
M. alba and | ][47] |
Black mulberry dietary syrup |
Administered in different concentrations in the diet of fish, the syrup, increased activities of serum lysozyme, myeloperoxidase, superoxide dismutase and catalase, and increased the expression levels of immune-related genes in the spleen and antioxidant-related genes in the liver of fish fed. |
[40] |
Rapeseed honey with mulberry leaves and fruits |
The addition of dried leaves and freeze-dried fruits (4%, w/v) to rapeseed honey added value to the product by increasing the content of flavonoids and phenolic acids and antioxidant capacity. |
[44] |
Black mulberry-aged wines |
The non-thermal processing applied at wine maturation point can be a potential method of improving the maturation process by modifying the chromatic properties of the wine. |
[38] |
In the volatile composition of the non-thermal, accelerated, aged wines, many volatile compounds were found that are grouped into nine chemical families: alcohols (32), esters (53), acids (14), volatile phenols (11), aldehydes (16), ketones (15), terpenes (11), lactones (11) and furans (3). |
[39] |
Black mulberry jam |
Black mulberries were processed into jam on an industrialized scale. The total phenols, flavonoids, anthocyanins and antioxidant capacity was significantly decreased but % recovery of bioaccessible the natural compounds increased after jam processing. |
[36] |
M. nigra | root |
Macerate extract |
As an active ingredient, at least one extract from the root of the plant is used, according to the invention. It is rich in moracenine A, moracenin B, kuwanon C, wittiorumin F and mulberrofuran T, also used in cosmetic composition and a pharmaceutical or nutraceutical composition. |
[54] |
US 2020/0178585 A1 |
Morus sp. fruits |
Savory concentrate/seasoning, with vegetable fat. |
Used as a cooking aid in the preparation of starch-rich food. |
[55] |
US 2020/0197429 A1 |
Astragalus root; phlorizin; M. alba root bark; olive leaf and bitter melon. |
Standardized extracts |
Dietary supplement with the aim of controlling postprandial blood sugar. |
[40] |
Dark chocolate with black mulberry |
Dark chocolate was fortified with dry black mulberry waste extract, encapsulated in chitosan-coated liposomes. This formula was shown to protect the anthocyanin content and increase the bioavailability of these pigments in vitro. |
[46] |
A patented formula containing
M. alba leaf extract (200 mg), along with berberine and red yeast rice powder has benefits on cardiovascular prevention in patients with dyslipidemia and reduces insulin resistance by protecting subjects from the side effects of smoking
[56].
Yimam et al., 2017, studied the effect of UP1306, a composition based on a patented mixture of heartwood of
Acacia catechu and the root bark of
Morus alba, with beneficial effect on joints, evidenced by the attenuation of symptoms associated with osteoarthritis in monosodium–iodoacetate-induced rats, reducing pain sensitivity, significantly improving the integrity of the articular cartilage matrix and causing minimal subchondral bone damage
[57].
An aqueous and ethanolic extract of
M. alba was developed (US7815949 B2) with estrogenic effects, and used for the treatment of climatic symptoms, osteoporosis and breast or uterine cancer
[58]. Another product (US2010/0166898 A1) from the bark of
Morus australis Poir, containing kiwanon H, was used as an antimicrobial agent
[59]. An ethanolic extract of white mulberry branches, which has a whitening effect, is the basis of another patent (US2006/0216253 A1)
[60].