EFFECT OF HIDE COLLAGEN ON THE AMINO ACID COMPOSITION OF BEEF PATTIES AND PORK SAUSAGE

Comminuted wet collagen from cattle hide was used to replace lean meat in a ground beef patty formulation at the 0,10 or 20% level and at the same level in a pork sausage formulation. The products were analyzed for amino acid composition by High Performance Liquid Chromatography. The products with collagen at all replacement levels showed a slight decrease in the essential amino acids but still retained approximately 75 to 85% of the total essential amino acids. Therefore, it was concluded that collagen from cattle hide may be used to replace a portion of the lean meat or fat meat in ground beef patties or pork sausage up to a 20% level while still providing much of the required dietary nutrition.     

不同种类的糖对中式香肠发酵的影响

葡萄糖、蔗糖、乳糖和麦芽糖对中式香肠发酵的影响进行了研究.结果表明,糖的添加有助于降低制品的pH值、增加乳酸量、减少亚硝酸盐残留量、促进良好风味的形成.37℃发酵36 h后,其pH值、乳酸量和亚硝酸盐残留量均与对照组有显著差异（P＜0.05）.发酵速率以葡萄糖组和蔗糖组较快,但这两者之间无显著差异（P＞0.05）.不同蔗糖添加量（1,2,4%）时,经36 h发酵,其PH值和乳酸量无明显差异（P＞0.05）.蔗糖用量为6%～8%时制品风味最佳.     

NSP酶的活力测定方法及其影响因素

概述了饲料工业测定NSP酶活力的常用分析方法，并对可能影响活力测定结果的影响因素进行了分析。     

EFFECT OF MICROBIAL GROWTH UPON MYOFIBRILLAR PROTEINS

SUMMARY— Aseptic samples from pig and rabbit muscles were inoculated with Achromobacter liquefaciens, Micrococcus luteus, Pediococcus cerevisiae, Pseudomonas fluorescens, Streptococcus faecal is end a mixed culture obtained from commercial hamburger. Some difficulty was encountered in getting the organisms to grow, and good growth was achieved only with A. liquefaciens end mixed culture from commercial meat. Both inoculated and uninoculated control samples were incubated at 3 and 10°C for 0, 8 and 20 days. The salt soluble proteins were extracted with Weber-Edsall solution and subjected to sucrose density gradient centrifugation, gel filtration and disc gel electrophoresis. The microorganisms utilized in this study had no measurable effect upon the myofibrillar proteins from either pig or rabbit muscle. However, bacterial growth decreased the amount of certain non-protein ultra-violet absorbing components in the ultracentrifugal pattern of Weber-Edsall extract. These components did not appear to be of myofibrillar origin. Disc gel patterns of Weber-Edsall extracts from pig muscle produced a more intensely staining band than those from rabbit muscle at R_m, = 0.59.     

ANTILISTERIAL ACTIVITY OF SODIUM, POTASSIUM OR CALCIUM LACTATE IN PORK LIVER SAUSAGE

The antilisterial activity of sodium, potassium or calcium lactate was tested in pork liver sausage (55% moisture, 2% sodium chloride). Lactate levels of 2, 3 or 4% (w/w) were used and the sausage was sterilized and inoculated with 10⁴–10⁵ cells/g of Listeria monocytogenes strain Scott A. Enhanced inhibitory effects of the organism were observed with increasing concentrations of the salts at two storage temperatures. At 20C, cell numbers in the controls increased by 5 log cycles after 10 days. The change in log CFU/g in samples treated with 4% of the lactate salts was: sodium, 1.4; potassium, 1.35, and calcium, -1.33. At 5C, cell numbers after 50 days of storage increased by 4.5 log cycles in controls, and changes in log CFU/g in samples treated with 3% lactate were: sodium, 0.88; potassium, -0.67, and calcium, -1.49. Increasing the sodium chloride content in the product enhanced the inhibitory effects. While L. monocytogenes grew better in heat processed (water bath) than in heat sterilized sausage, cell growth was suppressed during refrigerated storage by 3% of each of the lactate salts, and the effect of the calcium salt was superior to that of either the sodium or the potassium salt. Although addition of lactates to the sausage lowered the water activity, the change was not sufficient to account for the antilisterial activity of these salts .