diseases, obesity, and related diseases. Whereas, monounsaturated and polyunsaturated fatty acids have health benefits as cardio protectors due to their anti-inflammatory, antiarrhythmic, and antithrombotic effects [71]. Industry and consumers have shown interest in vegetable oils from different sources, such as olive, canola flaxseed, chia, avocado and moringa since the discovery of their health benefits (Table 2.1).
Oils with higher unsaturation degree are very susceptible to oxidation reactions during which their fatty acids decompose to small volatile molecules that generate unpleasant aromas and toxic compounds (aldehyde, ketones, epoxides, hydroxyl compounds). This leads to decrease the shelf life, functionality, nutritional value, and add safety concerns, as well as the non-acceptance by consumers. The strategy to reduce oils deterioration is microencapsulation, as will be explained in Section 2.3.3.
2.2.6 Bioactives From Agroindustrial Wastes
2.2.6.1 Commercial Edible Flowers
The climate conditions in many regions of Latin America enable the development of commercial flower crops, which is a fruitful business that combines the best of agriculture with refined commercial services. The main world flower producers are Colombia and Ecuador, but in the last decades, in countries such as Peru, Mexico, Chile or Bolivia floriculture has become an economic alternative to traditional regional productions and in Argentina the sector merged as a new agricultural actor. Floriculture is an intensive rural activity, located mainly in suburban areas, developed by almost entirely small and medium producers, with a strong social impact. The importance of this productive sector, lies in the contribution to the territorial development, the transfer of knowledge and the need for labor intensive. Through agricultural techniques with different degrees of technological development a great diversity of products is available for the community.
Table 2.1 Composition and health benefits of some vegetable oils from Ibero-America.
Oil source | Fatty acids composition (%w/w) | Benefits | Ref. | ||
---|---|---|---|---|---|
Oleic acid | Linoleic acid | Linolenic acid | |||
Olive | 66.4 | 16.4 | <1.0 | Anti-ulcer, anti-aging and plasma cholesterol-lowering properties. Increment of bone mineral density. | [72] |
Canola | 59.5 | 18.8 | 11.9 | Reduction of type 2 diabetes, osteoporosis risk, and cardiovascular disease. | [70] |
Flaxseed | 18.1 | 15.3 | 58 | Reduction of tumour growth at the later stage of carcinogenesis and LDL cholesterol level. | [71] |
Chia | 5.4 | 19.7 | 65.4 | Improvement in the fetal and infant growth and prevention of cardiovascular diseases. | [73] |
Avocado | 74 | 9.7 | <1.0 | Improvement in the blood lipid profiles (lowering LDL-cholesterol and triglycerides). | [74] |
Moringa | 78.2 | 1.29 | <1.0 | Reduction of rheumatism, hypertension and arthritis. | [75] |
Flowers contain natural nutrients, vitamins and bioactive compounds like phenolic acids, anthocyanins, betalains, and carotenoids [76]. The three latter are associated with the different colors of their petals, in a wide chroma spectrum [77, 78]. Rose petals have been used since ancient times in food preparation of salads, cakes, teas, desserts, drinks and innumerable meals [79]. These condiments have been maintained in the traditional kitchen in countries like China, Mexico and Brazil, and they have acquired notorious relevance due to their medicinal qualities and healthy properties.
Roses (Rose spp L., Family Rosaceae) occupy one of the first places in the world market. There is a huge variety of rose cultivars (more than 30,000) from different hybridizations, and new ones appear every year. The progenitor species mostly involved in the cultivars are: Rosa moschata Herrm., Rosa gallica L., Rosa damascene Mill., Rosa wichuraiana Crép., Rosa californica Cham. & Schltdl. and Rosa rugose Thunb. They are cultivated in commercial farms for the cut flower industry or to be sold as garden flower. In the time that it takes to obtain a plant of commercial size, several blooms are produced, which are discarded, leaving the material in the field. Therefore, in the search for an adequate use of discarded flowers, food, pharmaceutical and cosmetic industries are potential destinations [80].
Rose petals contain phenolics (flavonoids, tannins), carotenoids (β-carotene, lycopene), ascorbic acid, tocopherol and essential oils [81, 82]. Flavonoids, gallic acid, protocatechinic and chorogenic acid from rose petals extracts have shown anti-proliferative effect against cancer cells [83–85].
The predominant anthocyanins in red rose petals are pelargonidin and cyaniding glucosides [86]. These water-soluble pigments are associated to many health-promoting activities (against cancer, diabetics, and oxidative damage). They also arouse the interest of their potential use as natural food colorants [87].
Antimicrobial activity of Rosa Rugosa Thunb. methanolic extracts against eight bacteria has been reported [51]. Besides, ethanolic extracts of rose petals showed greater inhibition zone of Streptococcus pneumoniae and Pseudomonas aeruginosa than the maximum concentration of the antibiotic streptomycin [88].
On the other hand, the hexane fraction of R. rugose Thunb. was able to prevent oxidative damage by free radicals scavenging and inhibited lipid peroxidation [89].
In orange pink color rose varieties, important carotenes content was detected [90]. Some of them, such as β-carotene, and β-cryptoxanthin are vitamin A (retinol) precursors when ingested by mammals. The contribution of this vitamin to alleviate blindness, illness and premature death among children under five years of age and pregnant women [91] is well known. Carotenoid-rich diets have been also shown to be associated with a lower development rate of different cancers and chronic diseases [92].
2.2.6.2 Coffee Grounds as Source of Prebiotics
Due to the high consumption of coffee drinks, after extraction with hot water, coffee grounds are valuable primary products. During coffee processing, different by-products are generated such as: a) silver skin produced during the roasting of the coffee beans, after the previous removal of the outer skin and pulp of the dried fruit; b) coffee grounds generated after grinding and extraction with hot water of roasted coffee beans. Coffee grounds formed by small particles, while the silver coffee skin has a much larger particles and a large amount of soluble dietary fiber [93].
The composition of the coffee grounds comprises polysaccharides such as hemicelluloses, lignins, cellulose, lipids, proteins, caffeine and polyphenols [69]. Moreover,