Tham khảo tài liệu 'tự điển food science, technology and nutrition - vần x,y,z', nông - lâm - ngư, nông nghiệp phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 516 work See energy. wormseed See epazote. wort Aqueous extract of malt in brewing. See beer. WPC Whey protein concentrate. wraplings See wuntun. WTO World Trade Organization web site http . wuntun wonton Chinese small dough parcels containing meat boiled or deep fried. Also known as chiao-tzu or wraplings. X XangoldTM Natural source esters of the carotenoids xanthophyll and lutein. xanthaemia See carotinaemia. xanthan gum Complex polymer made by bacterial fermentation stable to wide range of pH and temperatures used as thickening agent to form gels increase viscosity in foods. xanthelasma Yellow fatty plaques on the eyelids due to hypercholesterolaemia. xanthine A purine intermediate in the metabolism of adenine and guanine to uric acid. caffeine in coffee and tea is 1 3 7-trimethylxanthine theophylline in tea is 1 3-dimethylxanthine theobromine in cocoa is 3 7-dimethylxanthine. xanthoma Yellow skin lesion associated with disorders of lipid metabolism and especially hypercholesterolaemia. xanthophylls Hydroxylated carotenoids. Occur in all green leaves together with chlorophyll and carotene also present in egg yolk cape gooseberry etc. Most have no vitamin a activity. Include flavoxanthin E-161a lutein 161b cryptoxanthin E-161c is vitamin A precursor rubixanthin 161e rhodoxanthin 161f canthaxanthin 161g . xanthoproteic reaction Test for proteins actually for the aromatic rings of phenylalanine tyrosine and tryptophan . Yellow colour on boiling with nitric acid turns orange on adding ammonia. xanthosis Yellowing of the skin associated with high blood concentrations of carotene. XenicalTM See orlistat. xenobiotic Substances foreign to the body including drugs and some food additives. xerophilic See osmophiles. xerophthalmia Advanced vitamin a deficiency in which the epithelium of the cornea and conjunctiva of the eye deteriorates because of impairment of the tear glands resulting in dryness then ulceration leading to blindness. 517 xerosis Abnormal .
