Effects of immersing culture of lactic acid bacteria from meat products on the tenderness and microbes in pork

The texture of meat often affects its palatability and tender meat tends to be more acceptable to the consumers. We investigated the effects of immersing pork into various lactic acid bacterial strain cultures that are used as starter for the fermented bioactive-meat products, on the texture and microbes in pork. According to the results, after immersing pork into the tested each lactic acid bacterial culture in our study, the maximum load value of pork immersed into Lactobacillus sakei strain 23 (LS-23) culture was significantly lower than that of untreated pork and that immersed into L. sakei JCM1157 (type strain) culture (P100kDa) bands in SDS-PAGE, reduction in pH, and increase in lactic acid concentration were observed in pork immersed in LS-23 culture compared to those in untreated pork and pork immersed in L. sakei type strain culture. Further, to identify the factor that led to a decrease in maximum load of pork immersed in LS-23 culture, we prepared the modified cultures (the supernatants at 4°C and 30°C, pH neutralized supernatant, LS-23 cell, and heat killed LS-23 cell suspensions) and immersed the pork into these cultures. As the results, the maximum load of pork immersed in pH neutralized culture was significantly elevated compared to that in LS-23 culture. In this study, the low maximum load value of pork is believed to be mostly due to the decrease in pH and elevation in lactic acid concentration in pork immersed into LS-23 culture. Moreover, the bacterial numbers of Staphylococci and psychrophiles in pork were significantly decreased by its immersion into LS-23 culture compared to those in untreated pork (P