FUZHOU UNIVERSITY FOOD CHEM工STRY 第一节概述 2.食品中的碳水化合物 碳水化合物占所有陆生植物和海藻干重 的3/4，它们广泛存在于所有的谷物、 蔬菜、水果以及其他人类能食用的植物 中。 最丰富的碳水化合物是纤维素，它们主 要存在于植物细胞壁中。 人类消费的主要食品碳水化合物是淀粉 和糖（葡萄糖、果糖、乳糖及蔗糖等） 淀粉是植物中最普遍贮藏能量的碳水化 合物，广泛分布在种子、根和块茎中
第一节 概述 2. 食品中的碳水化合物 • 碳水化合物占所有陆生植物和海藻干重 的3/4，它们广泛存在于所有的谷物、 蔬菜、水果以及其他人类能食用的植物 中。 • 最丰富的碳水化合物是纤维素，它们主 要存在于植物细胞壁中。 • 人类消费的主要食品碳水化合物是淀粉 和糖（葡萄糖、果糖、乳糖及蔗糖等） 。 • 淀粉是植物中最普遍贮藏能量的碳水化 合物，广泛分布在种子、根和块茎中
FUZHOU UNIVERS工TY FOOD CHEMISTRY Sugars in Fruits .Sugar of total fruit weight (Fennema,1985:Marcel Dekker) 20 ■glucose ■fructose e3ns %1M 86420 ☐sucrose ▣all 6 4 2 60 High in fructose;other sugars present also
• % Sugar of total fruit weight (Fennema, 1985; © Marcel Dekker) • High in fructose; other sugars present also 0 2 4 6 8 1 0 1 2 1 4 1 6 1 8 2 0 w t% sugar apple grape peach pear cherry straw - berry glucose fructose sucrose all Sugars in Fruits
FUZHOU UNIVERSITY FOOD CHEMISTRY Sugars in Vegetables .Sugar of total vegetable weight (Fennema,1985:Marcel Dekker) 10 9 口glucose ☐fructose ▣sucrose Iens %M 6 ▣all 54 2 1 0三 beet broc-onion spi-sweetsweet tomato lima pea coli nach corn potato beans Vegetables less sweet,higher in sucrose
Sugars in Vegetables • % Sugar of total vegetable weight (Fennema, 1985; © Marcel Dekker) • Vegetables less sweet, higher in sucrose beet broccoli onion spinach sweet corn sweet potato tomato lima beans pea 0 1 2 3 4 5 6 7 8 9 10 wt% sugar beet broccoli onion spinach sweet corn sweet potato tomato lima beans pea glucose fructose sucrose all
FUZHOU UNIVERSITY FOOD CHEMISTRY 2 History8amag那inks K四 How Cane Sugar is Made-the Basic Story Growing the Cane Sugar cane is a sub-tropical and tropical crop that prefers lots of sun and lots of water-provided that its roots are not waterlogged.It typically takes about 12 months to reach maturity although the time varies widely around the world from as short as six months in Louisiana to 24 months in some olaces.Where it differs from many crops is that it re-grows from the roots so the plant lasts many cycles [or 'ratoons'.a word derived from the Spanish to sprout]before it is worn out. More Detail The More Detail button will take you to the web sie of Kew Gardens in a separate window.You should retum here when you clse thet down again Harvesting Sugar cane is harvested by chopping down the stems but leaving the roots so that it re-grows in time for the next crop.Harvest times tend to be during the dry season and the length of the harvest ranges from as little as 2 months up to 11 months.The cane is taken to the factory.often by truck or rail w wagon but sometimes on acart pulled or a donkeyl More Detall Extraction The first stage of processing is the extraction of the cane juice.In many factories the cane is crushed in a series of large roller mills:similar to a mangle [wringer]which was used to squeeze the water out of clean washing a century ago.The sweet juice comes gushing out and the cane fibre is cared ay foruse in the boilers in other factories a diffuser is used asis described for beet sugar manufacture.Either way dirty the soil from the fields.some small fibres and the green extracts from the plant are all mixed in with the sugar
FUZHOU UNIVERSITY FOOD CHEMISTRY Sugars in Processed Foods .Sugar of total food weight 9007430 ▣Glucose ☒Glucose/Fructose Sucrose Lactose All sugars dnuppy wIopouue
Sugars in Processed Foods • % Sugar of total food weight