Effect of nitrite and propolis preservative on volatile basic nitrogen changes in meat products.

Pig meat was treated with 0.3% ethanol extracted propolis (EEP), 0.3% water extracted propolis (WEP), 0.4% dried residue of ethanol extracted propolis (DREEP) and 0.2% potassium sorbate (PS). The samples were stored for 8 weeks at 4, 10 and 20 degrees C, respectively. Volatile basic nitrogen (VBN) tests were carried out to measure the influence of temperature after 0, 2, 4 and 8 weeks. The VBN value in 0.3% EEP pork sausages was the lowest for all treatments after 8 weeks of storage at 4 degrees C. The 0.3% EEP treatment was superior to the 0.2% PS treatment. This was due to the lower VBN of the former than that of the latter. Hence, EEP, WEP and DREEP can serve as good chemical preservatives of pork meat products and can contribute to promote human health because they are naturally produced.