Survival of encapsulated probiotics in pasteurized grape juice and evaluation of their properties during storage

Abstract

In this study, probiotic bacteria such as Lactobacillus acidophilus and Bifidobacterium bifidum were encapsulated in alginate beads with a mean diameter of 54.25 ± 0.18 µm by internal gelation. Encapsulated and free cells as control samples were then added to the pasteurized grape juice and stored for 60 days. At the end of the storage period, the survivability of the bacteria in the encapsulated samples was significantly ( P<0.05) higher than that in the free cells (8.67 ± 0.12 and 7.57 ± 0.08 log cfu mL−1 for L. acidophilus and 8.27 ± 0.05 and 7.53 ± 0.07 log cfu mL−1 for B. bifidum for encapsulated and free forms, respectively). The results generally showed a decrease in °Brix, pH, and color, whereas acidity and turbidity have increased the in probiotic grape juice after the storage period of 60 days. For all treatments, the numbers of surviving cells were more than the recommended minimum (107 cfu g−1) at the end of the storage period.

Survival and stability of free and encapsulated probiotic bacteria under simulated gastrointestinal conditions and in pasteurized grape juice

“…From the data it was concluded that the treatments that contains nonfree (encapsulated) bacteria recorded minimum about mouthfeel of the juice. A similar result was found by Mokhtari et al (). He also suggested that optimizing bacteria may reduce this problem.…”

“…G2 treatment contained B. bifidum in free form; therefore, due to an increase in the acidic content in juice the chances for the survival of B. bifidum lessens which results in a rapid decline in its population. According to Mokhtari et al (), B. bifidum may not survive the acidic conditions of the grape juice that supports the results of present study. To increase the chances of its viability of probiotics, these were encapsulated with two different encapsulating material sodium alginate and k‐carrageenan.…”

“…After 35 days of storage, no color change was observed except G2. As reported by Mokhtari et al (), acid production by free bacteria may affect the nutrients and sensory profile of fruit juice and hence change in color was observed by most of the evaluators. When mean results from the flavor parameter were observed, results showed a significant difference.…”

“…(Rúa et al, 2018). For this purpose, grape juice can be a potential carrier of probiotics owing to its nutritional profile (Mokhtari, Jafari, & Khomeiri, 2019;Panghal et al, 2018).…”

“…Microencapsulation of B. bifidum was carried out with a little modification in the internal gelation method according to Mokhtari, Jafari, and Khomeiri (2018). Shortly, 60 ml of sodium alginate and k-carrageenan was mixed with 10 ml of cell solution.…”