Study On Partial Properties Of Two Lactic Acid Bacteria And Their Application In Low-temperature Fermented Sichuan Sausages

This paper ,with the objects of Pediococcus pentosaceus (P.p) and Lactobacillus curvatus (L.c), mainly studied their partial properties. this result showed, they could grow goodly on condition of 4% salt, be no nitrate reduction activity, cellulose decomposition activity and catalase activity, and could ferment the cane sugar. On condition of the a liquid meat simulation medium(MSM) and fermenting for 10 days at a contant temperature of 10"C, they were able to grow goodly and produce goodly acid, so they adapted themselves to the fermented low-temperature sausages of Sichuan, but P.p growed and produced sour more rapidly than L.c, namely, with comparison to L.c, P.p adapted more goodly itself to the low -temperature fermented sausages.The fermentation was performed at MSM, at the contant temperature of 10℃, and in test tubes. This paper studied the effects of different concentration of hot pepper, Pericarpium Zanthoxyli, and capsaicin on the growth and producing acid of L.c and P.p. By the measurements of OD₆₈₀ value and pH value, comparing to the reference, which showed their effects on the growth and acid production of them were inhibitory function or promoting function, the result showed this. (1) For hot pepper(Hp) at concentration of 1%, 2% , 4% (wt/v), they promoted the growth of P.p. For 1% Hp, the promoting function was most obvious with comparison to 2% and 4%. For 2% and 4% Hp, the promoting function was less obvious than that of 1% Hp. 1%. 2% and 4% Hp accelerated acid production of P.p, however, the accelerating function of 1% and 4% Hp was approximate and most obvious, and that of 2% Hp was less obvious than 1% Hp . 2% and4%1% Hp promoted the growth of L.c and accelerated acid production of it, however, the promoting function and accelerating function did not show the difference was significant. (2) For capsaicin(Cap) at concentration of 5,10 and 20μg/ml(wt/v), 20 and 10 μg/ml Cap inhibited the growth of P.p to a certain degree. 20 μg/ ml Cap inhibited it most obviously, 10μg/ml Cap did more obviously, and 5μg/ml Cap didn't. With the increase of culturing time, they had no inhibition in the end. With comarision to the reference, 10 and 20μg/ml Cap was less obvious inhibition of acid production of P.p, however, 20μg/ml Cap was more than obvious inhibition of it than 10μg/ml Cap , 5μg/ml Cap wasn't. 20μg/ml Cap delayed the growth of L.c for six days, and 10μg/ml Cap did it for four days. With the increase of the concentration of Cap, the function of inhibiting the growth of L.c was increased gradually. 20 μg/ml Cap inhibited it most obviously, 10μg/ml Cap did more obviously, but 5μg/ml Cap did less obviously between 96 hours and 192 hours. In the end, 5μg/ ml Cap didn't it. With the increase of the concentration of Cap, the function of inhibiting acid production of Lc was increased gradually. In a word, Cap inhibited more...