due to a number of organic acids, notably oxalic acid, which contributes about a tenth of the total acidity of 2–2.5% (This is double or triple the oxalate content of spinach and beets.) Rhubarb leaves are said to be toxic in part due to their high oxalate content, as much as 1% of the leaf weight, but other chemicals are probably also responsible Today rhubarb is available much of the year thanks to greenhouse production, though some cooks prefer the more intense flavor and color of the field-grown crop of late spring The color of red stalks is best preserved by minimizing both the cooking time and the quantity of added liquid, which dilutes the pigments Fruits From Warm Climates: Melons, Citrus Fruits, Tropical Fruits, and Others Melons Except for the watermelon, melons are fruits of Cucumis melo, a close relative of the cucumber (C sativus) and a native of the semiarid subtropics of Asia The melon plant was domesticated in central Asia or India and arrived in the Mediterranean at the beginning of the 1st century CE, where their large size and rapid growth made them a common symbol of fertility, abundance, and luxury There are many melon varieties with distinctive rinds, flesh colors (orange types are an excellent source of beta-carotene), textures, aromas, sizes, and keeping qualities Melons are generally used fresh, either sliced or pureed They contain a proteindigesting enzyme, cucumisin, and thus will prevent gelatin gels from setting unless the enzyme is denatured by cooking or an excess of gelatin is used The melon surface can become contaminated with microbes in the field and cause food poisoning when the microbes are introduced into the flesh during ...Except for the watermelon, melons are fruits of Cucumis melo, a close relative of the cucumber (C sativus) and a native of the semiarid subtropics of Asia The melon plant was domesticated in central Asia or India and. .. was domesticated in central Asia or India and arrived in the Mediterranean at the beginning of the 1st century CE, where their large size and rapid growth made them a common symbol of fertility, abundance, and luxury There are many melon varieties with... sliced or pureed They contain a proteindigesting enzyme, cucumisin, and thus will prevent gelatin gels from setting unless the enzyme is denatured by cooking or an excess of gelatin is used The melon surface can