Quantification of Process Lethality (5-Log Reduction) of <i>Salmonella</i> and Salt Concentration during Sodium Replacement in Biltong Marinade

Salt (sodium chloride, NaCl) is commonly used in ready-to-eat (RTE) meat products such as biltong, a South African style dried beef product for flavor, enhanced moisture loss, and reduction of microbial growth. However, increased consumption of high sodium content foods is commonly associated with h...

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Bibliographic Details
Main Authors: Caitlin Karolenko, Peter Muriana
Format: Article
Language:English
Published: MDPI AG 2020-10-01
Series:Foods
Subjects:
Online Access:https://www.mdpi.com/2304-8158/9/11/1570
Description
Summary:Salt (sodium chloride, NaCl) is commonly used in ready-to-eat (RTE) meat products such as biltong, a South African style dried beef product for flavor, enhanced moisture loss, and reduction of microbial growth. However, increased consumption of high sodium content foods is commonly associated with high blood pressure and heart disease. This study evaluated the use of alternative salts, potassium chloride (KCl) and calcium chloride (CaCl<sub>2</sub>) in the biltong marinade to achieve a ≥ 5-log reduction of <i>Salmonella</i>, a pathogen of concern in beef products. Beef pieces (1.9 cm × 5.1 cm × 7.6 cm) were inoculated with a five-serovar mixture of <i>Salmonella</i> (<i>Salmonella</i> Thompson 120, <i>Salmonella</i> Enteritidis H3527, <i>Salmonella</i> Typhimurium H3380, <i>Salmonella</i> Heidelberg F5038BG1, and <i>Salmonella</i> Hadar MF60404), vacuum-tumbled in a traditional biltong marinade of salt, spices, and vinegar containing either NaCl, KCl or CaCl<sub>2</sub> (2.2% concentration) followed by an 8–10 day drying period at 23.9 °C (75 °F) and 55% relative humidity. Microbial enumeration of <i>Salmonella</i> was conducted following inoculation, after marination, and after 2, 4, 6, 8, and 10 days of drying in a humidity/temperature chamber. Biltong produced with CaCl<sub>2</sub>, NaCl, or KCl achieved a > 5-log reduction of <i>Salmonella</i> after 6, 7, and 8 days, respectively. The <i>Salmonella</i> reduction trends with biltong made with NaCl or CaCl<sub>2</sub> were not significantly different (<i>p</i> < 0.05) while both were significantly different from that made with KCl (<i>p</i> > 0.05). Sodium, calcium, and potassium ion concentrations were measured using ion-specific electrode meters following biltong processing and drying. As expected, the biltong made with the corresponding salt had the most abundant ion in the sample. Regardless of the salt used in the marinade, the potassium ion levels were moderately elevated in all samples. This was determined to be from potassium levels naturally present in beef rather than from other ingredients. Sampling of several commercial brands of biltong for sodium content showed that some were significantly above the allowable level of claims made on package ingredient statements. The substitution of NaCl with KCl or CaCl<sub>2</sub> during biltong processing can also provide a 5-log reduction of <i>Salmonella</i> to produce a safe product that can be marketed as a more healthy low-sodium food alternative that may appeal to consumers who need to reduce their blood pressure and are conscientious of sodium levels in their diet.
ISSN:2304-8158