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چکیده
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High-methoxyl pectin (HMP, 72.5 % esterification degree and galacturonic acid content of 67.9 %) was extracted from grape pomace using a sequential ultrasound-microwave extraction. The extracted HMP was used to develop low-fat synbiotic set yogurts containing probiotic cells. Higher grape pomace pectin (GPP) concentrations (0.5–2 %) increased the probiotic bacterial population of Lactobacillus acidophilus LA-5 and Bifidobacterium bifidum BB- 12. Higher cell viability was observed for L. acidophilus LA-5 compared to B. bifidum BB-12. A response surface optimization showed that the presence of 8.08 Log CFU mL 1 L. acidophilus LA-5 and 1.88 % HMP experimentally resulted in the best probiotic viability (10.83 ± 0.11 Log CFU mL 1), overall acceptability (8.03 ± 0.06), and pH (4.25 ± 0.05) values. Compared to pectin-free probiotic yogurts, the optimal yogurt gels presented higher probiotic survivability, lower syneresis, and superior storage-dependent sensory attributes during 21 days of storage. However, a 14-day storage period was generally deemed suitable
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