|Abstract: ||本研究收集之市售食用海藻樣品，計有6項紅藻、6項褐藻及2項綠藻，分析調查其一般成分、游離胺基酸 (FAA)、礦物質、微量元素、有毒重金屬等之含量。14種海藻之水分介於7~ 44 % 之間、灰分7~ 39 %、粗蛋白2~ 28 %，樣品間成分含量差異甚大，粗脂肪含量皆極少。pH 値介於 5.78~10.21之間，紅藻類pH値在6.67~10.21間，較偏弱鹼性，褐藻及綠藻pH在5.78~7.00間，較偏弱酸性，部分藻類pH 値甚高，可能是因業者在加工過程中加鹼洗滌導致。海藻之FAA含量在不同種類間差異甚大，昆布與海茸頭高達1716~2671 mg/100 g，但南極綠藻、珊瑚藻與海帶芽則皆低於100 mg/100 g，在14種藻類中，紫菜含最多種類之FAA，褐藻類有較高量之天門冬胺酸、麩胺酸、丙胺酸，石蓴類則較其它藻類含更多的牛磺酸。藻中巨量礦物質之鈉含量 (706~91975 ppm)、鉀 (991~88191 ppm)、鈣 (1847~29453 ppm)、鎂 (1170~37915 ppm) 等皆高，不同藻類之巨量礦物質差異亦甚大。市售海藻之微量元素之鐵含量為36~927 ppm、錳0~5.76 ppm、鉻0~0.04 ppm、銅0.8~21.4 ppm、鋅1.28~23.13 ppm，除了鉻微量外，其他元素在不同藻類間之差異顯著，即使是同種之石蓴，不同樣品的鐵和錳含量亦有極顯著之差異。14種海藻樣品中，石花含有高達3.46 ppm的鉛，其餘海藻含量少，紅藻平均鉛含量高於褐藻及綠藻，依藻類食品衛生標準以含 85 ％水分之新鮮藻類計算後，所有樣品未超過法規鉛限量。所有樣品皆含有鎘，但皆未超標，汞介於0.02~0.04 ppm之間，亦符合安全標準。石花含有高達809 ppm的鋁、紫晶藻461 ppm、紫菜357 ppm，可能是使用含之鋁膨鬆劑所導致。海藻中之砷含量介於0.84~46.36 ppm之間，而三價砷與五價砷等無機砷含量換算成含 85 ％ 水分後，所有樣品皆未超過法規限量之1.0 ppm。本研究結果提供海藻基本營養素、呈味成分、微量元素、礦物質和有害重金屬含量之資料，可做為消費者日常膳食挑選及有關單位訂定藻類食品標準之參考。|
The purpose of this study is to analyze proximate compositions, free amino acids (FAA), minerals, trace elements and heavy metals in edible seaweed samples. They were 6 kinds of red seaweed and brown seaweed, and 2 kinds of green seaweed samples which were collected from the market. There are significant differences in proximate composition among seaweeds. The moisture in 14 kinds of seaweed ranged from 7 to 44%¸ ash 2 to 28%, and crude protein 2 to 28%. Trace amounts of crude lipid were found in all samples. The pH value in the seaweed products was between 5.78-10.21. Red seaweed was in a weakly alkaline ranged from 6.67 to 10.21, and brown and green seaweed were in a weakly acidity from 5.78 to 7.00. Some seaweeds had much higher pH value. It might due to wash and clean seaweeds with alkaline solvent during processing. There is remarkable difference in the content of free amino acid (FAA) among species. Saccharina japonica and Durvillaea antarctica had high levels of FAA with 1716-2671 mg/100g, but those of Eucheuma denticulatum, Eucheuma serra and Undaria pinnatifida were lower than 100 mg/100 g. Porphyra dentata had more kinds of FAA among samples. Brown seaweeds possessed higher amounts of aspartic acid, glutamic acid and alanine. For Ulva lactuca, it had much more taurine than any other seaweeds. There is remarkable difference in the contents of minerals in seaweeds. The amount of sodium ranged 706-91975 ppm, potassium 991-88191 ppm, calcium 1847-29453 ppm, and magnesium 1170-37915 ppm were found in seaweeds. For the trace elements in the seaweed products, the amount of iron was 36-927 ppm, manganese 0-5.76 ppm, chromium 0-0.04 ppm, copper 0.8-21.4 ppm, and zinc 1.28-23.13 ppm. The amounts of trace elements showed significant difference in different species of seaweeds expect for chromium. Even the same species of Ulva lactuca, the contents of iron and manganese in different samples also showed remarkable difference. There was 3.46 ppm of lead in Gelidium amansii, but other seaweeds has less. The average amount of lead in red seaweed was higher than those of brown and green seaweed. According to food sanitary standards, all samples meet the regulation limit as calculated the moisture of seaweed with 85% of moisture such as fresh one. Cadmium was found in samples, but all are under the limit. The contents of mercury ranged from 0.02-0.04 ppm which was in compliance with the limit. The high levels of aluminum were found in Gelidium amansii (809 ppm), KappapHycus alvarezii (461 ppm) and PorpHyra dentate (357 ppm). The use of aluminum as leaveners in those seaweeds may result in high levels of aluminum in the products. The amount of arsenic in the seaweed products was between 0.84-46.36 ppm. Inorganic arsenic As2O3 and NaAsO3 of the samples do not exceed the regulation limit 1 ppm after converting the moisture of seaweed to 85%. The results could provide the information regarding basic nutrient substances, flavor compounds, trace elements, minerals and heavy metals in seaweeds. It also could be a reference for consumers to purchase edible seaweed and for government agency to set the limit standard of seaweed.