Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Avda. Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Avda. Agustín Escardino 7, 46980 Paterna, Valencia, Spain.
Int J Food Microbiol. 2018 Oct 3;282:84-91. doi: 10.1016/j.ijfoodmicro.2018.06.004. Epub 2018 Jun 8.
Slow fermented sausages with reduced ingoing amounts of sodium nitrate were manufactured: control (250 ppm), 15% (212.5 ppm) and 25% (187.5 ppm) reduction. The effect of nitrate reduction on microbiology and chemical parameters, volatile compounds and aroma production was studied. Parameters like, pH, a and colour decreased during ripening, without being affected by nitrate reduction. Lipid oxidation increased during ripening and it was higher in control sausages due to fat content. Residual nitrite was below the detection limit during the whole process and residual nitrate decreased during ripening, with higher reduction in RN25 sausages. Lactic acid bacteria, total mesophilic bacteria and yeasts and moulds increased during ripening but Gram positive cocci decreased. Microbial counts from nitrate reduced sausages at the end of the manufacturing process were not statistically different from the control sausages with nitrate. Regarding volatile compounds formation, compounds derived from amino acid degradation were increased by nitrate reduction. Aroma compounds derived from amino acid degradation and responsible for strong odours, dimethyl disulphide (toasted, garlic) and methional (cooked potato) and, to a lesser extent, compounds derived from esterase activity producing fruity odours (ethyl acetate, ethyl butanoate, ethyl‑2‑hydroxypropanoate, ethyl‑2‑methylbutanoate and ethyl‑3‑methylbutanoate) and several compounds from carbohydrate fermentation acetic acid (vinegar odour) and 2-butanone (fruity) were related to the high nitrate reduction (25%). Despite nitrate reduction up to 25% produced minor effect on microbial growth, their metabolism is regulated by nitrate content and therefore by nitrite generation affecting the production of key aroma compounds that alter the sausage aroma profile.
研究了减少亚硝酸盐添加量（分别为 250ppm、15%（212.5ppm）和 25%（187.5ppm））对微生物学和化学参数、挥发性化合物和香气产生的影响。在成熟过程中，pH 值、a 值和颜色等参数下降，但不受硝酸盐还原的影响。脂质氧化在成熟过程中增加，由于脂肪含量，对照香肠中的脂质氧化更高。在整个过程中，残留亚硝酸盐均低于检测限，而残留硝酸盐在成熟过程中减少，RN25 香肠中的减少幅度更高。在成熟过程中，乳酸菌、总需氧细菌和酵母和霉菌增加，但革兰氏阳性球菌减少。制造过程结束时，硝酸盐减少香肠中的微生物计数与含硝酸盐的对照香肠没有统计学差异。关于挥发性化合物的形成，氨基酸降解产生的化合物因硝酸盐还原而增加。源自氨基酸降解的香气化合物和负责强烈气味的化合物，如二甲基二硫（烤面包、大蒜）和甲硫醛（煮熟的土豆），以及在较小程度上，源自酯酶活性产生水果味的化合物（乙酸乙酯、丁酸乙酯、2-羟基丙酸乙酯、2-甲基丁酸乙酯和 3-甲基丁酸乙酯）和几种碳水化合物发酵产生的化合物（醋酸气味）和 2-丁酮（水果味）与高硝酸盐还原（25%）有关。尽管硝酸盐还原高达 25%对微生物生长的影响较小，但它们的代谢受硝酸盐含量的调节，因此受亚硝酸盐生成的影响，这会影响关键香气化合物的产生，从而改变香肠的香气特征。
