醬油醪殘渣之理化性質與機能性之研究

Abstract

中文摘要 本研究利用榨出醬油後的醬油醪殘渣，經水洗、過篩、冷凍乾燥、研磨等步驟處理後製成膳食纖維粉末，經離體試驗分析其物化性並以動物模式探討降血脂之生理機能。 本研究脫鹽醬渣(desalted mash residue，DMR)的製備步驟簡易，製備流程包括：水洗、脫鹽、乾燥及研磨。將DMR以酵素方法測定其膳食纖維含量有52.4﹪，比較實驗組與控制組(纖維素cellulose)之物化性體積密度(bulk density )、保水性(water-holding capacity)、吸油性(oil-holding capacity)、膨脹性(swelling ability)及陽離子交換力(cation-exchange capacity) ，均有明顯差異。經HPLC分析DMR中可利用性(bioavailable)的異黃酮daidzein及genistein含量，分別為1200 to 1480 μmol/100 g (daidzein 約 3040-3759 μg/g ， genistein 約 3240-3996 μg/g)。 進一步以動物模式研究脫鹽醬渣(DMR)降血脂的效果，DMR分別以10%、15%、20% (w/w%)取代部份飼料，餵養十周齡的倉鼠(hamster)，經八週飼養後，分析控制組及實驗組(DMR取代部份飼料)的肝臟脂肪含量、血脂濃度，實驗組均顯著地比控制組低而且肝臟脂質過氧化測定 (Thiobarbituric acid-reactive substances ,TBARs) 及糞便膽固醇的排出量與控制組有顯著地差異。 本研究所製備的脫鹽醬渣(DMR)除了含豐富膳食纖維其物化性質經測定具有保水、吸油、抑制澱粉酶活性等作用，可做為食品工業中膳食纖維的來源外，其中含抗氧化功能的異黃酮，更增加脫鹽醬渣成為保健食品的價值。

ABSTRACT Fiber-rich materials including desalted shoyu mash residue (briefly referred as desalted mash residue, (DMR), alcohol-insoluble solid (AIS) and water-insoluble solid (WIS) were prepared from shoyu mash residue, which is a filtration cake obtained during the isolation of shoyu by press filtration of fermented matrix in the final process. The DMR, AIS and WIS contain rich dietary fiber of 52.4, 61.5 and 54.7% by weight, respectively. The DMR, AIS and WIS all have significantly lower bulk densities, higher water-holding capacities, oil-holding capacities, swelling abilities and cation-exchange capacities than the control cellulose. These results indicated that the said fiber-rich materials prepared in this study all have the desired physicochemical properties for being used as satisfactory sources of dietary fibers or low-calorie bulk ingredients in food applications requiring oil and moisture retention. Furthermore, the said fiber-rich materials also have high contents of isoflavones, mainly daidzein and genistein that are considered as the most bioavailable phytoestrogens, with a total amount of about 1200 to 1480 μmol/100 g (equal to daidzein of ca. 3040-3759 μg/g, or genistein of 3240-3996 μg/g). The effects of DMR-supplemneted diet on cholesterol absorption in hamsters were investigated and compared with those of a cellulose-containing diet, as control. Comparison of test and control treatments indicated an elevated high-density lipoprotein (HDL) cholesterol concentration and a significantly reduced serum low-density lipoprotein, triglyceride, total liver lipid and liver cholesterol on the test diet. The significant fecal bile acids excretion of test diets may be contributed to the hypolipidemic effects of DMR. Furthermore DMR also contains rich amount of isoflavone, genestein and daidzein, which are considered as the most bioavailable phytoestrogen and antioxidant. The results revealed that the said fiber-rich materials might be a potent fiber sources for health foods.