et al. (2008) also reported that L. acidophilus La5 showed growth insoymilk with the fermentation time reaching to 12e17 h.In this study, the addition of apple juice to soymilk increasedthe number of L. acidophilus slightly of about 0.25 and 0.35 logunits for the apple juice concentrations of 15 and 25%, respectively.On the other hand, the increase in the numbers ofL. acidophilus for these samples were not significantly differentfrom the control samples (P > 0.05). Bozanic et al. (2008) reportedthat the addition of sugar (5% glucose or sucrose) tosoymilk before fermentation did not influence the fermentationtime and the number of L. acidophilus.The survival of L. acidophilus in the fermented soymilk drinksduring storage at 4 C for 21 days was given in Table 2. No significantdifferences between the numbers of L. acidophilus duringdifferent storage days were obtained (P > 0.05). During the storageperiod of 21 days, the numbers of L. acidophilus were in the range of8.73e9.11 log cfu/g. According to Turkish Food Codex Communiqueon Fermented Milk (No: 2009/25), acidophilus milk must contain atleast a minimum of 6 log cfu/g total specific microorganisms(Anonymous, 2009). In our study, acidified soymilk beverage withor without added apple juice met this criterion with a minimumL. acidophilus count of about 8.73 log cfu/g. Other studies alsoconfirmed the higher survival rates of probiotic bacteria in fermentedsoymilk products. €Ozbey, Topçu, and Saldamlı (2007)reported that the number of L. acidophilus in yogurts containing 15%soymilk increased significantly about 0.65 log cfu/g after 14 days ofstorage. Beasley, Tuorila, and Saris (2003) observed that Lactococcuslactis (LL3) survived at levels of over 8 log cfu/ml in the fermentedsoy milk products containing strawberry (3%) and glucose (2%) for 3weeks. Wang et al. (2002) reported that regardless of whether ornot sucrose (15 Bx) was added, no marked changes in the numbersof L. acidophilus (about 8 log cfu/ml) were observed during 10 daysof storage at 5 C. Lin et al. (2004) also reported that supplementationof milk-soymilk mixture with different amounts of Lyciumchinense Miller juice did not affect the growth of Lactobacillusparacasei subsp. paracasei and Bifidobacterium longum; the cellnumbers for both starters were about the same. On the contrary tothe findings of this study, it was indicated that, L. acidophilus survivedpoorly during 21 days of cold storage and the viable cell countwas under the 106 cfu/ml as soon as after the first week of storage(Bozanic et al., (2011).Yeasts and mold growths were not detected (<10 cfu/g) duringthe storage period of 21 days at 4 C for each sample. Similar to thisstudy, Beasley et al. (2003) also reported that they could not detectthe growth of yeast or mold in the fermented soymilk products(<10 cfu/ml).The incubation temperatures of 37 C (Wang et al., 2002) and42e43 C (Ashraf & Shah, 2011) were used for the fermentedproducts with L. acidophilus. In the present study, fermentationtemperature of 37 C was used. Bozanic et al. (2008) reported that37 C was more appropriated than 43 C for all tested probioticbacteria.3.3. Rheological properties of fermented soy milk beveragesMost of the studies related to the fermented beverages havebeen focused on the fermentation process in terms of microbiotawhile the determination of rheological parameters and sensoryproperties can devote the additional quality characteristics of fermentedfoods.
การแปล กรุณารอสักครู่..
