Ghaderi-Ghahfarokhi Maryam, Yousefvand Amin, Ahmadi Gavlighi Hassan, Zarei Mehdi, Farhangnia Peyman
Department of Food Hygiene Faculty of Veterinary Medicine Shahid Chamran University of Ahvaz Ahvaz Iran.
Department of Food Science and Technology Faculty of Agriculture Tarbiat Modares University Tehran Iran.
Food Sci Nutr. 2020 Jun 29;8(8):4491-4504. doi: 10.1002/fsn3.1752. eCollection 2020 Aug.
Tragacanth gum (TG) displayed a prebiotic activity, but its application was restricted due to high viscosity and deterioration of organoleptic and textural characteristics of food. In this study, TG was depolymerized by Pectinex Ultra Color enzyme followed by membrane separation (30 kDa) to get pectinase hydrolyzed fraction of tragacanth gum (PHFTG) with molecular weight more than 30 kDa. The average molecular weight of PHFTG was 147.7 ± 11.5 g/mol having a fucoxylogalacturonan structure. The prebiotic activity was tested using PHFTG, TG, and inulin as a carbon source. The results showed that the count of in PHFTG- and inulin-supplemented media increased significantly during the 48-hr fermentation ( < .05). Five batches of low-fat set yogurts were prepared by the following formulation: Control (without both and prebiotic), LC-Cont (containing ), LC-PHFTG (containing + 0.5% PHFTG), LC-TG (containing + 0.05% TG), and LC-In (containing + 0.5% inulin), and population and physicochemical properties were monitored during 21-day storage at 4°C. The number of remained highly acceptable (8.54-8.61 log CFU/g) during 7-21 days of storage in LC-PHFTG. LC-In and LC-PHFTG presented significantly lower syneresis and higher sensory acceptability than LC-Cont and Control during storage ( < .05). LC-TG displayed weaker body and texture, lower sensory acceptability, and higher syneresis than other samples. This study provides support for expanding the utilization of PHFTG as a potential prebiotic and fat replacer in non- or low-fat dairy products with satisfactory sensory quality.
黄芪胶（TG）具有益生元活性，但其应用因高粘度以及食品感官和质地特性的劣化而受到限制。在本研究中，用果胶酶（Pectinex Ultra Color）对黄芪胶进行解聚，然后进行膜分离（30 kDa），以获得分子量大于30 kDa的果胶酶水解黄芪胶级分（PHFTG）。PHFTG的平均分子量为147.7±11.5 g/mol，具有岩藻糖基半乳糖醛酸聚糖结构。以PHFTG、TG和菊粉作为碳源测试益生元活性。结果表明，在48小时发酵期间，添加PHFTG和菊粉的培养基中的[具体微生物名称未给出]数量显著增加（P<0.05）。按照以下配方制备了五批低脂凝固型酸奶：对照（既不添加[具体物质未给出]也不添加益生元）、LC-Cont（含有[具体物质未给出]）、LC-PHFTG（含有[具体物质未给出]+0.5% PHFTG）、LC-TG（含有[具体物质未给出]+0.05% TG）和LC-In（含有[具体物质未给出]+0.5%菊粉）；在4°C下储存21天期间监测[具体微生物名称未给出]数量和理化性质。在LC-PHFTG中储存7至21天期间，[具体微生物名称未给出]数量仍保持在高度可接受水平（8.54 - 8.61 log CFU/g）。在储存期间，LC-In和LC-PHFTG的脱水收缩率显著低于LC-Cont和对照，感官可接受性更高（P<0.05）。LC-TG的质地和口感较弱，感官可接受性较低，脱水收缩率高于其他样品。本研究为扩大PHFTG作为潜在益生元和脂肪替代物在感官品质良好的非脂或低脂乳制品中的应用提供了支持。
