## 4 Nutritional and Bioactive Potential of Fresh Fruit and Vegetable Waste
### Dietary Uses of Fruit and Vegetable Waste  
The inclusion in our diet of fruit and vegetable spare parts, often seeds and peels that are discarded and here generically considered as waste, is not new. Banana peels and blossoms, for instance, have been widely consumed for centuries as a curry, boiled, fried, etc. in Asia (Sri Lanka and India) and some countries in Latin (Brazil) and Central America (Caribbean islands) [155]. In Ethiopia, the Indian wild banana _Ensete superbum_ (Cliff banana) is the main staple food because this variety is very resistant to severe drought. Moreover, its seeds have been used for generations to treat several health problems such as diabetes, leukorrhea, kidney stones, and dysuria [182]. Banana flowers, pseudostem, and unripe fruits are also consumed as vegetables by many indigenous communities [183], including rural peoples in India [184]. Despite the popularity of the fruit, banana peels are not used in the human diet in most developing countries. Recently, however, the growing concerns of consumers about the sustainability of the planet placed cooking banana peels under social media attention. Hopefully, [PERSON]'s banana peel curry [185] will trigger a change in the way we consider fruit and vegetable waste in our diet. Similarly, banana blossoms seem to be a very versatile food to substitute meat proteins, taking into consideration the great number of different potential recipes such as curries, fish and chips, linguini, paella, salads, soups, fish pies, and crab cakes. Beyond the historic use of banana waste in the human diet, which would be the strongest argument that it is a safe procedure, evidence from different studies demonstrates the nutritional and bioactive value of such waste. Boiling bananas, often plantain or cooking banana varieties, increases the phenolic compound content of banana [159] because heat softens the vegetable structures, therefore releasing the bioactive compounds into the medium. In this case, banana peel prevents the loss of those bioactives in the water. Similar studies reported an increase in phenolic content during thermal processing of banana peel [186; 184]. For most people, the hairy skin of kiwi fruit is not very appellative to eat. However, not only are the peels edible, eating skin-on kiwi greatly increases nutrient intake, namely of fibers, vitamins C and E, and a great number of bioactive compounds [101; 187]. Consumption of whole SunGold kiwifruit (including the skin), for instance, was shown to increase the fiber, vitamin E and folate contents by 50, 32, and 34%, respectively [188]. To facilitate the ingestion of kiwi skin, the hairs can be easily removed by rubbing the fruit, scrubbing it with a vegetable brush, or scraping it lightly with a spoon. Tannins are widely present in many fruits, particularly in their wasted parts, such as citrus and banana peels. This abundance is the main reason why consumers reject those parts because tannins confer high astringency and unpleasant flavors. When present in lower amounts, however, tannins are more easily tolerated by consumers, as occurs with the proanthocyanidus present in grape skins. Different strategies, however, can be used to mitigate the high abundance of tannins, such as sweetening to obtain marimalades and jams, or fermentation to obtain beverages, such as petache [73]. This is a traditional Mexican beverage that is obtained by fermentation of different fruits and fruit waste, according to the region where it is produced. Pineapple rinds and tamarind, banana peels, corn husks, crushed corn, persimmon, apple, jujube, pomegranate, plum, cranberry, sour cherry, soursp, mango, orange, and papaya are among the petache varieties in traditional Mexican food folklore [73]. Although there are not many studies in the literature about these traditional fermented beverages, it is known that the use of fruit during the fermentation process of beverages such as beer enhances the content of bioactive compounds, in particular polyphenols and carotenoids [86].