Di Cagno Raffaella, Lòpez Clemencia Chaves, Tofalo Rosanna, Gallo Giovanna, De Angelis Maria, Paparella Antonello, Hammes Walter P, Gobbetti Marco
Department of Plant Protection and Applied Microbiology, University of Bari, via G. Amendola 165/A, 70126 Bari, Italy.
Meat Sci. 2008 Jun;79(2):224-35. doi: 10.1016/j.meatsci.2007.09.006. Epub 2007 Sep 15.
Three Italian PDO fermented sausages, Varzi, Brianza and Piacentino, were compared for compositional, microbiological, biochemical and volatile profile characteristics. Mean values for the gross composition varied especially due to moisture, fat, total protein and nitrate concentration which reflected differences in the ingredients and some technological parameters. Cell numbers of the major microbial groups were almost similar among sausages. The major differences were found for Brochothrix thermosphacta, enterococci and moulds. Apart from their use as starters, Lactobacillus sakei and Lactobacillus curvatus were the dominant lactic acid bacteria and, as well as Staphylococcus xylosus, dominated the population of coagulase-negative staphylococci. Sausages differed for the hydrolysis of myofibrillar proteins and secondary proteolysis. Varzi, the sausage subjected to prolonged fermentation at 23-25°C for 10 days before ripening, showed the highest degree of secondary proteolysis. Varzi and Brianza, the two fermented sausages manufactured by using microbial starters, showed the highest concentration and similar profiles of free amino acids. The peptidase activities contained in the aqueous extracts agreed with the above findings. A total of 52 volatile components, mainly alcohols, aldehydes and terpenes, were identified by solid-phase micro-extraction coupled with gas chromatography-mass spectrometry analysis. The volatile profiles of the three Italian PDO fermented sausages differed in part and, except for terpenes, the highest levels of the other chemical classes were found in Varzi and Brianza sausages. The composition of free fatty acids of the three Italian PDO sausages was rather similar. Monounsaturated fatty acids (MUFA) were found at the highest relative percentage followed by saturated (SFA) and polyunsaturated (PUFA) fatty acids. Oleic, palmitic, linoleic and stearic were the main free fatty acids found in all fermented sausages.
对三种意大利受保护地理标志（PDO）发酵香肠——瓦尔齐（Varzi）、布里安扎（Brianza）和皮亚琴察诺（Piacentino）——的成分、微生物、生化和挥发性成分特征进行了比较。粗成分的平均值存在差异，特别是由于水分、脂肪、总蛋白和硝酸盐浓度不同，这反映了原料和一些工艺参数的差异。各香肠中主要微生物类群的细胞数量几乎相似。主要差异存在于嗜热栖热放线菌、肠球菌和霉菌中。除用作发酵剂外，清酒乳杆菌和弯曲乳杆菌是优势乳酸菌，与木糖葡萄球菌一样，在凝固酶阴性葡萄球菌群体中占主导地位。各香肠在肌原纤维蛋白水解和二次蛋白水解方面存在差异。瓦尔齐香肠在成熟前于23 - 25°C进行了10天的长时间发酵，其二次蛋白水解程度最高。使用微生物发酵剂生产的两种发酵香肠瓦尔齐和布里安扎，游离氨基酸浓度最高且谱图相似。水提取物中的肽酶活性与上述结果一致。通过固相微萃取结合气相色谱 - 质谱分析共鉴定出52种挥发性成分，主要为醇类、醛类和萜类。三种意大利PDO发酵香肠的挥发性成分谱部分存在差异，除萜类外，其他化学类别的最高含量出现在瓦尔齐和布里安扎香肠中。三种意大利PDO香肠的游离脂肪酸组成相当相似。单不饱和脂肪酸（MUFA）的相对百分比最高，其次是饱和脂肪酸（SFA）和多不饱和脂肪酸（PUFA）。油酸、棕榈酸、亚油酸和硬脂酸是所有发酵香肠中发现的主要游离脂肪酸。
