King Amanda M, Glass Kathleen A, Milkowski Andrew L, Sindelar Jeffrey J
Department of Animal Sciences, University of Wisconsin-Madison, 1805 Linden Drive, Madison, Wisconsin 53706, USA.
Food Research Institute, University of Wisconsin-Madison, 1550 Linden Drive, Madison, Wisconsin 53706, USA.
J Food Prot. 2015 Aug;78(8):1527-35. doi: 10.4315/0362-028X.JFP-14-491.
The antimicrobial impact of purified and natural sources of both nitrite and ascorbate were evaluated against Clostridium perfringens during the postthermal processing cooling period of deli-style turkey breast. The objective of phase I was to assess comparable concentrations of nitrite (0 or 100 ppm) and ascorbate (0 or 547 ppm) from both purified and natural sources. Phase II was conducted to investigate concentrations of nitrite (50, 75, or 100 ppm) from cultured celery juice powder and ascorbate (0, 250, or 500 ppm) from cherry powder to simulate alternative curing formulations. Ground turkey breast (75% moisture, 1.2% salt, pH 6.2) treatments were inoculated with C. perfringens spores (three-strain mixture) to yield 2.5 log CFU/g. Individual 50-g portions were vacuum packaged, cooked to 71.1°C, and chilled from 54.4 to 26.7°C in 5 h and from 26.7 to 7.2°C in 10 additional hours. Triplicate samples were assayed for growth of C. perfringens at predetermined intervals by plating on tryptose-sulfite-cycloserine agar; experiments were replicated three times. In phase I, uncured, purified nitrite, and natural nitrite treatments without ascorbate had 5.3-, 4.2-, and 4.4-log increases in C. perfringens, respectively, at 15 h, but <1-log increase was observed at the end of chilling in treatments containing 100 ppm of nitrite and 547 ppm of ascorbate from either source. In phase II, 0, 50, 75, and 100 ppm of nitrite and 50 ppm of nitrite plus 250 ppm of ascorbate supported 4.5-, 3.9-, 3.5-, 2.2-, and 1.5-log increases in C. perfringens, respectively. In contrast, <1-log increase was observed after 15 h in the remaining phase II treatments supplemented with 50 ppm of nitrite and 500 ppm of ascorbate or ≥75 ppm of nitrite and ≥250 ppm of ascorbate. These results confirm that equivalent concentrations of nitrite, regardless of the source, provide similar inhibition of C. perfringens during chilling and that ascorbate enhances the antimicrobial effect of nitrite on C. perfringens at concentrations commonly used in alternative cured meats.
在熟食风格火鸡胸肉的热加工后冷却阶段，评估了纯化和天然来源的亚硝酸盐和抗坏血酸盐对产气荚膜梭菌的抗菌作用。第一阶段的目的是评估来自纯化和天然来源的亚硝酸盐（0或100 ppm）和抗坏血酸盐（0或547 ppm）的可比浓度。第二阶段旨在研究来自芹菜汁培养粉的亚硝酸盐（50、75或100 ppm）和来自樱桃粉的抗坏血酸盐（0、250或500 ppm）的浓度，以模拟替代腌制配方。将火鸡胸肉碎（75%水分，1.2%盐，pH 6.2）处理接种产气荚膜梭菌孢子（三菌株混合物），使其含量达到2.5 log CFU/g。将50克单独的样品真空包装，煮至71.1°C，在5小时内从54.4°C冷却至26.7°C，并在额外的10小时内从26.7°C冷却至7.2°C。通过在胰蛋白胨-亚硫酸盐-环丝氨酸琼脂平板上培养，在预定时间间隔对产气荚膜梭菌的生长进行三次重复样品检测；实验重复三次。在第一阶段，未腌制、纯化亚硝酸盐和无抗坏血酸盐的天然亚硝酸盐处理在15小时时产气荚膜梭菌分别增加了5.3、4.2和4.4个对数，但在含有来自任何一种来源的100 ppm亚硝酸盐和547 ppm抗坏血酸盐的处理中，冷却结束时观察到增加量小于1个对数。在第二阶段，0、50、75和100 ppm的亚硝酸盐以及50 ppm亚硝酸盐加250 ppm抗坏血酸盐分别使产气荚膜梭菌增加了4.5、3.9、3.5、2.2和1.5个对数。相比之下，在补充了50 ppm亚硝酸盐和500 ppm抗坏血酸盐或≥75 ppm亚硝酸盐和≥250 ppm抗坏血酸盐的其余第二阶段处理中，15小时后观察到增加量小于1个对数。这些结果证实，无论来源如何，等效浓度的亚硝酸盐在冷却过程中对产气荚膜梭菌具有相似的抑制作用，并且抗坏血酸盐在替代腌制肉类常用浓度下增强了亚硝酸盐对产气荚膜梭菌的抗菌作用。
