目的 嗜酸乳酸桿菌經褐藻酸鈣固定化後，應用於番茄汁中進行發酵，以提升菌株在發酵產品中之存活率。方法 發酵原料採用由新鮮番茄製得之番茄汁，內中包含菌體之細胞固定化膠球之直徑約2.6mm，發酵時間為80小時，並另以游離態菌體進行發酵以作為對照組。結果 在固定化細胞的發酵過程中，細胞生長會導致細胞由膠球漏出，並持續在番茄汁中生長。在固定化細胞發酵組中，番茄汁內的最終活菌數達10^7 CFU/mL，而膠球中則高於10^10 CFU/mL-gel，在游離態細胞發酵組中之最終活菌數則約為10^9 CFU/mL。固定化細胞能克服番茄汁中的不利條件，因此獲得優於游離態細胞的結果。在隨後的4℃ 10週貯藏過程中，發酵番茄汁中的固定化嗜酸乳酸桿菌之活菌數仍能維持10^7 CFU/mL-gel的濃度，而游離態活菌數只有10^4 CFU/mL。貯藏過程中官能品評的結果，亦顯示內中包含固定化嗜酸乳酸桿菌者要優於包含游離態者。結論 本研究結果顯示利用褐藻酸鈣固定化嗜酸乳酸桿菌來發酵番茄汁，能有效提升發酵成品的活菌數及感官品質。
Purpose. Ca-alginate entrapped Lacto bacillus acidophilus was used to ferment tomato juice and enhance the survival of the bacteria in the product. Method. L acidophilus was immobilized in gel beads with diameters of about 2.6 mm. Tomato juice was made from fresh raw tomatoes, followed by fermentation for 80 h with free and immobilized cells. Results. Immobilized cells leaked from the gel beads and proliferated in the juice during the fermentation; the final viable cell number reached 10^7 CFU/mL in the juice and above 10^10 CFU/mL-gel in gel beads. Free cells reached about 10^9 CFU/mL during fermentation. Immobilized cells endured the adverse conditions in tomato juice; furthermore, viable cell numbers and sensory score results were higher compared with free cells. The viable cell counts of immobilized L. acidophilus were maintained at 10^7 CFU/mL-gel in the fermented tomato juice after 10 weeks of cold storage at 4℃, compared with 10^4 CFU/mL of free cells. Conclusions. Ca-alginate immobilized L acidophilus enhanced the viable cell number and improved the sensory quality of fermented tomato juice. Our findings could be applied to the development of probiotic tomato juice.
