**2.2. Orange flesh sweet potato (***Ipomoea batatas***)**

Sweet potato (*Ipomoea batatas* (L.) Lam.) is a typical vegetable of tropical and subtropical countries (Mozambique), being one of the most consumed in Brazil, mainly by low-income populations. It occupies the sixth position among the most cultivated vegetables in the country, being an excellent source of energy and protein for the families of small farmers in the Northeast and South regions. It presents no difficulties in its cultivation, besides being very resistant to the dry climate, having a great capacity of adaptation, and is one of the largest energy producers per unit of area and time. Another advantage is that it requires low financial investments, with high returns having great importance in animal feed, industrial production of flour and starch and can be cooked in different styles in boiling water [16, 17].

It is a herbaceous crop with extensive growth in tropical and subtropical regions of the world, being important in many developing countries. Archeological, linguistic, and historical evidences establish that sweet potatoes originated in the region of Central and South America. The ability of this crop to adapt to a wide variety of climatic conditions allowed for its development in tropical and temperate regions of Africa, Asia, and the Americas. Compared to other crops, sweet potatoes are able to grow at an accelerated rate under various environmental conditions and are highly adaptable under marginal growing conditions. It has a short production cycle, high nutritional value, and sensory versatility in terms of color, flavor, and texture [18].

In Brazil, sweet potato presents low average productivity due to the occurrence of pests and diseases, inadequate production technology, and the absence of selected cultivars. However, improved productivity can be easily achieved through the use of seedlings from disease-free matrices obtained from tissue culture laboratories [17].

Its forms of consumption are the same as those of other sweet potato cultivars, as well as having similar production techniques. Its planting can be carried out at any time of the year, provided that the minimum local temperature in the period is equal to or above 15°C [16].

In the form of flour, *Beauregard* sweet potato is a possible total or partial substitute of wheat flour in recipes, allowing its introduction in school meals and in basic baskets [16]. Its high content of β-carotene, on average 115 μg.g−1 of root, gives intense orange coloration to its pulp [16]. Carvalho et al. [19] found 111.44 μg g−1 of total carotenoids, 104.17 μg g−1 of β-carotene, 13-*cis* isomer 3.38 μg g−1 and 9-*cis* isomer 1.49, respectively, in the raw roots in the same variety, somewhat lower than was found before.

Many authors evaluated the β-carotene content in orange sweet potato cultivars and found variable contents: Hangenimana et al.—79.84 μg g−1 [20], Takahata et al.—187.00 μg g-1 [21], Lako et al.—150.0 μg g−1 [22], Kidmose et al.—108.0 μg g−1 [23], Teow et al.—226.00 μg g−1 [24], Wu et al.—84.00 μg g−1 [25], and Failla et al.—281.00 μg g-1 [26].

The average found for the centesimal composition in orange flesh sweet potato was moisture—83.91 g 100 g−1, ash—0.52 g 100 g−1; protein—0.69 g 100 g−1; lipids—0.10 g 100 g−1; carbohydrates—13.42 g 100 g−1, respectively, with a caloric value of 57.34 kcal 100 g−1 [19].

evaluate bioaccessibility of carotenoids and on lipophilic antioxidant activity. Bioaccessibility of carotenoids was reduced after all treatments, except for *cis*-violaxanthin and neoxanthin, which increased 79% in beverages treated with high intensity pulse electric fields and high pressure processing. The thermal treatment presented worst decreasement of the bioaccessibility in 63%. High-intensity pulse electric fields and high pressure processing can be considered as promising

Sweet potato (*Ipomoea batatas* (L.) Lam.) is a typical vegetable of tropical and subtropical countries (Mozambique), being one of the most consumed in Brazil, mainly by low-income populations. It occupies the sixth position among the most cultivated vegetables in the country, being an excellent source of energy and protein for the families of small farmers in the Northeast and South regions. It presents no difficulties in its cultivation, besides being very resistant to the dry climate, having a great capacity of adaptation, and is one of the largest energy producers per unit of area and time. Another advantage is that it requires low financial investments, with high returns having great importance in animal feed, industrial production

It is a herbaceous crop with extensive growth in tropical and subtropical regions of the world, being important in many developing countries. Archeological, linguistic, and historical evidences establish that sweet potatoes originated in the region of Central and South America. The ability of this crop to adapt to a wide variety of climatic conditions allowed for its development in tropical and temperate regions of Africa, Asia, and the Americas. Compared to other crops, sweet potatoes are able to grow at an accelerated rate under various environmental conditions and are highly adaptable under marginal growing conditions. It has a short production cycle, high nutritional value, and sensory versatility in terms of color, flavor, and texture [18]. In Brazil, sweet potato presents low average productivity due to the occurrence of pests and diseases, inadequate production technology, and the absence of selected cultivars. However, improved productivity can be easily achieved through the use of seedlings from disease-free

Its forms of consumption are the same as those of other sweet potato cultivars, as well as having similar production techniques. Its planting can be carried out at any time of the year, provided that the minimum local temperature in the period is equal to or above 15°C [16]. In the form of flour, *Beauregard* sweet potato is a possible total or partial substitute of wheat flour in recipes, allowing its introduction in school meals and in basic baskets [16]. Its high content of β-carotene, on average 115 μg.g−1 of root, gives intense orange coloration to its pulp [16]. Carvalho et al. [19] found 111.44 μg g−1 of total carotenoids, 104.17 μg g−1 of β-carotene, 13-*cis* isomer 3.38 μg g−1 and 9-*cis* isomer 1.49, respectively, in the raw roots in the same vari-

Many authors evaluated the β-carotene content in orange sweet potato cultivars and found variable contents: Hangenimana et al.—79.84 μg g−1 [20], Takahata et al.—187.00 μg g-1

Lako et al.—150.0 μg g−1 [22], Kidmose et al.—108.0 μg g−1 [23], Teow et al.—226.00 μg g−1 [24],

[26].

[21],

of flour and starch and can be cooked in different styles in boiling water [16, 17].

technologies to obtain nutritive and functional beverages.

matrices obtained from tissue culture laboratories [17].

ety, somewhat lower than was found before.

Wu et al.—84.00 μg g−1 [25], and Failla et al.—281.00 μg g-1

**2.2. Orange flesh sweet potato (***Ipomoea batatas***)**

110 Progress in Carotenoid Research

The orange sweet potato pulps have the potential to be used as food-based supplements to reduce vitamin A deficiency since β-carotene is one of the carotenoids with pro-vitamin A activity for human diet, exerting important functions in human physiology, acting as antioxidants, as protective pigments of the human retina, and as precursors of retinoids that influence gene expression [27].

Orange-fleshed sweet potato (OFSP) is a carotenoid-rich vegetable. Thermal treatment to process sweet potatoes can decrease the contents of these compounds in foods, reducing their bioactive properties. Raman spectroscopy can be employed as a fast tool in food analysis, especially to detect low concentrations of carotenoids and to monitor their degradation profile along time. Sebben et al. [28] evaluated two drying methods, hot air and microwave in a rotating drum, coupled to quantitative Raman spectroscopy. A 50% decrease in the carotenoid contents were found for both types of drying methods. The results were reproducible. The best linear correlations were R2 = 0.90 for hot air and 0.88 for microwave dried samples, respectively.

Vitamin A deficiency (VAD) is a public health problem in some regions of Brazil. Enhancement of the use of orange-fleshed sweet potatoes as a pro-vitamin A source can be a strategy for prevention of this deficiency. Berni et al. [29] compared the pro-vitamin A contents, vitamin A equivalencies and β-carotene (βC) bioaccessibilities of two varieties (*Beauregard* and Amelia) of home-cooked orange sweet potatoes and two commercial ones. Pro-vitamin A carotenoid content in home cooked *Beauregard* variety was higher than in Amelia variety and in commercial products for babies. All-*trans*-βC was the most abundant carotenoid in all samples (raw, cooked, and commercial) as expected. Boiling and frying decreased total β-carotene. According to them, a portion of 100 g fresh weight of *Beauregard* contained over 100% of the estimated average requirement for children and women and up to 92% estimated average requirement for lactating women. The efficiency of micellarization of all-*trans*-βC after the in vitro digestion was relatively low (4–8%) and significantly less than for *cis*-isomers, the amounts of *trans*-βC captured into micelles from boiled *Beauregard* and fried Amelia varieties were higher than in micelles obtained from the digestion of commercial ones. Bioaccessibility of pro-vitamin A carotenoids in the micelle fraction of digested OFSP was confirmed in assays of Caco-2 human intestinal cells. They suggested that agricultural development of these two varieties: Amelia and *Beauregard* (biofortified), riches in *trans*-βC, and the improvement of home cooking styles can be strategies to increase the consumption of this food to reduce VAD in Brazil.

Islam [27] analyzed total carotenoids and *trans* and cis-β-carotene in different varieties of raw and cooked orange-fleshed sweet potato (OFSP) aiming to reduce VAD using plant-based foods. Intravarietal difference in carotenoids as well as in *trans* and *cis-*β-carotenes were found both in raw and boiled potatoes. Carotenoid content was higher in raw potatoes compared to boiled samples from the same variety, as expected by solids dissolution. Amongst the varieties, Kamalasundari (BARI SP-2) contained the highest amount of carotenoids both in raw and boiled samples. The β-carotene was significantly higher in Kamalsundari and BARI SP-5 varieties, while *trans*-β-carotene was found the major carotenoid in all of the raw potatoes. Boiling resulted in an increase in *cis-*β*-*carotene and a decrease in the *trans-*isomer contents. The use of Kamalsundari and BARI SP-5 orange-fleshed sweet potatoes was proposed as potential food-based supplements to reduce vitamin A deficiency.

the orange color. The β-carotene content varied from 0.16 to 0.47 μg g−1 in breads with yellow sweet potato flour. The results suggest that the use of yellow sweet potato in breads can be

Carotenoids in Raw Plant Materials

113

http://dx.doi.org/10.5772/intechopen.78677

A great number of pumpkin varieties, each of which contains a different amount of carotenoids, are cultivated worldwide [33]. In several Brazilian regions, *C. moschata* cultivars are known to contain a particularly high amount of α- and β-carotene. The β-carotene has 100%

Carotenoids have antioxidant activity, but few are converted in retinol (an active form of vitamin A) by the human body. Among more than 600 carotenoids which have pro-vitamin A activity, the most known are α- and β-carotene, and these are susceptible to degradation

There are various studies about carotenoids from pumpkins, mainly β-carotene, and the large diversity of landraces and cultivars, among them the *Cucurbita maxima, Cucurbita moschata,* and *Cucurbita pepo.* The differences in carotenoids and β-carotene contents in these three species are important in order to choose the best one for cultivation and biofortification [19]. For instance, studies carried out by Carvalho et al. [19] revealed a large range of contents of carotenoids among samples of the same species of *Cucurbita moschata*. The total carotenoids content varied from 124.87 to 557.20 μg g−1 and others were above

Priori et al. [38] evaluated the genetic variability for the synthesis of bioactive compounds, total phenolic compounds, carotenoids, antioxidant activity, and minerals of 10 accesses of pumpkin (*C. moschata*) landraces. They found a high genetic variability for the synthesis of phenolic compounds, carotenoids, antioxidant activity, and minerals, with the most promis-

The manioc plant (*Manihot esculenta*, Crantz) belongs to the Euphorbiaceae family being native to South America, cultivated by the Indians responsible for its dissemination. The Portuguese spread it to other continents, especially Africa and Asia The plant is a bush of bulky roots, leaves petiolated and yellowish chalice flowers, arranged in panicles. Its tubercle is also known as cassava, aipim, castelinha, macacheira, cassava, sweet cassava, and cassava

In Brazil, there are about 1200 varieties, classified as bitter or sweet according to its hydrocyanic acid content. Originated from South America, manioc (*Manihot esculenta*, Crantz), present in the indigenous culture and other ancient populations, has its historical importance because it has been the main energetic source for several generations of these peoples. It is still one of the main energy foods in the African, Latin American, and Asian continents, to about 500

ing C52 and C389 accessions, due to their high levels of total carotenoids.

**2.4. Yellow sweet cassava (***Manihot esculenta***)**

according to the regions where it is cultivated [13].

million people, especially in developing countries [39].

beneficial for consumers' health and for the agricultural business as well.

pro-vitamin A activity, and α-carotene has 53% pro-vitamin A activity [34–37].

(isomerization and oxidation during the cooking process).

**2.3. Pumpkins (***Cucurbita moschata***)**

60 μg.g−1.

Sweet potatoes have been the aim of research over the years due to their functional and nutritional properties. Carbohydrates, proteins, lipids, carotenoids, anthocyanins, phenolic acid conjugates, and minerals constitute versatile nutrients in different parts (tubers, leaves, stems, and stalks) of sweet potato. The unique composition of sweet potato provides various beneficial effects such as antioxidant, hepatoprotection, anti-inflammatory, anticancer, antidiabetic, antimicrobial, anti-obesity, and antiaging activities. Factors which affect the nutritional composition and bio-function of sweet potatoes include the varieties, parts of the plants, extraction time and solvents, post-harvest storage and processing. Differences between the *in vitro* and *in vivo* assays employed for bio-function evaluation also lead to variations in results from different studies, which makes direct comparisons inadequate or difficult. Leaves, stems, and stalks from sweet potatoes are still commercially underutilized. Results from several studies point out that sweet potato can be developed as a sustainable crop for different nutritionally enhanced and value-added food products aiming at the promotion of human health [30].

Sweet potato (*Ipomoea batatas* (L.) Lam) is one of the most popular and ancient roots in Brazil, which is consumed cooked, baked or as sweets, cooked in boiling water. Cooking can result in physicochemical transformations which modify its nutritional properties. Vizzotto et al. [31] evaluated physicochemical characteristics, bioactive compounds, and the antioxidant activity of 12 genotypes of raw and roasted sweet potato, with different pulp colors: cream pulp, orange pulp, and purple pulp. Total soluble solids, acidity, sugars, carotenoids, anthocyanins, phenolic compounds contents, and antioxidant activity show a wide variation of these parameters for both forms of preparation. Antioxidant activity varied considerably amongst the genotypes, from 210.29 to 7870.57 μg trolox equivalent.g−1 for pulps *in natura* and from 773.26 to 17,306.22 μg trolox equivalent g−1 for baked pulps. Contents of soluble solids, acidity, sugars, and bioactive compounds as well as total antioxidant activity were higher while the levels of carotenoids were lower in baked sweet potatoes than *in natura*. Genotype and color of sweet potatoes influenced their chemical composition. Cultivars Amelia and *Beauregard* stood out with respect to the amount of soluble solids and carotenoids, respectively. Selections of purple have to be recommended as sources of anthocyanins. Thermal processing influenced the concentration of antioxidant compounds and affected some of the physicochemical characteristics.

Yellow sweet potato is mostly produced in small scale by farmers. It is a source of energy and carotenoids in the human diet; however, it is a highly perishable crop. To increase its industrial use, yellow sweet potato flour was produced for use in bakery products. Nogueira et al. [32] evaluated the technological quality and the carotenoid content in sweet breads produced by replacing wheat flour with 0, 3, 6, and 9% yellow sweet potato flour. The increase in yellow sweet potato flour concentrations in bread resulted in a decrease of specific volume and firmness and an increase in water activity, moisture, orange coloring, and carotenoids. Storage led to the most significant changes after the 5th day, with a reduction in intensity of the orange color. The β-carotene content varied from 0.16 to 0.47 μg g−1 in breads with yellow sweet potato flour. The results suggest that the use of yellow sweet potato in breads can be beneficial for consumers' health and for the agricultural business as well.
