Effect of Pre-Processing Steps, Nitrite and Irradiation Combination Preservation of a Ready-to-Eat Spinach Relish and Sorghum Porridge Meal

Renatus P. Shilangale

Central Veterinary Laboratory, Ministry of Agriculture Water and Forestry, Windhoek, Namibia.

DOI: 10.4236/fns.2012.37116                

Abstract

The effects of pre-processing steps (washing, blanching and cooking) and combination preservation of irradiation (10 kGy) and nitrite (0, 50, 100, 150 and 200 mg·kg^–1) on the survival of Clostridium sporogenes spores in a ready-to-eat (RTE) spinach relish and sorghum porridge meal were investigated. Chlorine wash (250 mg^–1) reduced the C. sporogenes counts in spinach by 1.6 log cycles. Blanching following the chlorine wash caused no significant decrease in the spore counts in spinach. On the other hand, cooking significantly reduced the counts in the porridge by about 1.7 log cycles. In both components of the meal, there was a significant decrease in the Clostridia counts with increased sodium nitrite levels. However, the counts increased in the sorghum porridge component after 12 d of storage at 10℃. Cooking alone significantly reduced the final nitrite levels in both components of the meal. In both components of the meal, nitrite in combination with irradiation reduced the C. sporogenes counts to less than 10 cfu/g. A safe RTE spinach relish and sorghum porridge meal could be expected when a pre-processing, followed by a combination treatment of at least 50 mg·kg^–1 sodium nitrite and a target dose of 10 kGy is applied.

Keywords

Ready-to-Eat (RTE) Meal; Nitrite; Irradiation

Conflicts of Interest

The authors declare no conflicts of interest.

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