Dept. of Food Physics and Meat Science, Inst. of Food Science and Biotechnology, Univ. of Hohenheim, Garbenstrasse 21/25, 70599, Stuttgart, Germany.
J Food Sci. 2020 Feb;85(2):289-297. doi: 10.1111/1750-3841.15010. Epub 2020 Jan 22.
The purpose of the study was to investigate the effect of a reduced pH value (5.1 instead of 5.5 to 5.6) on the properties of highly perishable, spreadable raw fermented sausages (onion mettwurst) with or without the addition of homopolysaccharide (HoPS)-producing lactic acid bacteria (LAB). Hence, sausages with HoPS-producing LAB and a pH value of 5.1 were produced and compared to sausages (pH 5.1) produced with a non-exopolysaccharide (EPS)-forming strain (Lactobacillus sakei TMW 1.2037). Microbial growth and pH values were monitored during processing (24 °C for 48 hr, 10 °C for 24 hr) and storage (14 days at 0 to 2 °C). Furthermore, fat (Weibull-Stoldt) and EPS contents were determined in the final products. Sausages were characterized using texture profile and sensory analysis. The fat contents ranged from 16% to 19% and the determined EPS concentrations ranged from 0.17 to 0.59 g/kg for L. sakei TMW 1.411 and Lactobacillus curvatus TMW 1.1928 and from 0.67 to 1.58 g/kg for L. curvatus TMW 1.51. The strains L. sakei TMW 1.411 and L. curvatus TMW 1.51 reduced the hardness of the samples significantly (P < 0.05) compared to the control samples. Regarding spreadability and mouthfeel, sausages containing an EPS-forming culture were rated slightly better than the control samples and the taste was not negatively influenced. PRACTICAL APPLICATION: This study clearly demonstrated that it is promising to apply HoPS-producing LAB to maintain the spreadability of pH-reduced (pH 5.1) spreadable raw fermented onion mettwurst, which may prospectively give the opportunity to increase the safety of this highly perishable product.
本研究旨在探讨降低 pH 值（5.1 而非 5.5 至 5.6）对高易腐、可涂抹的生发酵香肠（洋葱麦特瓦尔斯特）特性的影响，同时考虑添加或不添加同型多糖（HoPS）产生的乳酸菌（LAB）。因此，制作了添加 HoPS 产生 LAB 且 pH 值为 5.1 的香肠，并与 pH 值为 5.1 的非胞外多糖（EPS）形成菌株（Lactobacillus sakei TMW 1.2037）制作的香肠进行了比较。在加工过程中（24°C 持续 48 小时，10°C 持续 24 小时）和储存过程中（0 至 2°C 下储存 14 天）监测微生物生长和 pH 值。此外，还测定了最终产品中的脂肪（Weibull-Stoldt）和 EPS 含量。使用质地剖面和感官分析对香肠进行了表征。脂肪含量在 16%至 19%之间，Lactobacillus sakei TMW 1.411 和 Lactobacillus curvatus TMW 1.1928 的 EPS 浓度范围为 0.17 至 0.59g/kg，Lactobacillus curvatus TMW 1.51 的 EPS 浓度范围为 0.67 至 1.58g/kg。与对照样品相比，Lactobacillus sakei TMW 1.411 和 Lactobacillus curvatus TMW 1.51 显著降低了样品的硬度（P<0.05）。关于涂抹性和口感，含 EPS 形成培养物的香肠的评分略优于对照样品，且味道不受负面影响。实际应用：本研究清楚地表明，应用 HoPS 产生的 LAB 来维持 pH 值降低（pH 5.1）的可涂抹生发酵洋葱麦特瓦尔斯特的涂抹性是有希望的，这可能为提高这种高度易腐产品的安全性提供机会。
