EFFECT OF DIETARY PROTEIN AND FAT LEVELS ON LIVER AND URINARY BLADDER NEOPLASIA IN MICE FED 2-ACETYLAMINOFLUORENE

Weanling female BALB/c mice were continuously fed diets containing combinations of 12 or 24% protein, 4 or 24% fat and 500 ppm of 2 acetylaminofluorene (2-AAF) for 78 weeks. Mice on the high fat diets demonstrated a significant increase in the incidence of hepatocellular neoplasms and urinary bladder carcinomas. The incidence of both liver tumors and bladder tumors was reduced in the mice fed low fat and low protein diet compared to the other three diets. The protein levels alone appeared to have no effect on the incidence of bladder tumors or liver tumors. Mice fed the diet with lower levels of fat and protein showed a significant decrease in the incidence of bladder carcinomas compared to the mice fed the higher levels of fat andlor protein.     

EFFECT OF CUCURBITA FICIFOLIA FRUIT EXTRACT ON LIPID PROFILE AND ORAL GLUCOSE TOLERANCE IN STREPTOZOTOCIN-INDUCED DIABETIC RATS

Cucurbita ficifolia ( C. ficifolia ) commonly known as pumpkin is a cultivated plant whose fruit can be used for treating various diseases, one of which is diabetes mellitus. This study was undertaken to investigate the effects of long term feeding of C. ficifolia fruit extract on blood glucose, lipid profiles and the oral glucose tolerance test in streptozotocin (STZ)-induced type 1 diabetic rats. Treatment for 30 days showed a significant decrease in blood glucose, triglyceride, low density lipoprotein and a significant increase in high density lipoprotein level. A significant effect on oral glucose tolerance was also noted. Chronic administration showed an improvement in the oral glucose tolerance curve. These results suggest that C. ficifolia fruit extract exhibits hypoglycemic as well as hypolipidemic effects in the STZ-induced diabetic rats.

PRACTICAL APPLICATIONS

Cucurbita ficifolia , also referred to as pumpkin, is commonly used as a traditional remedy for diabetes in Asia, Africa and South America. The present study investigated the hypoglycemic and hypolipidemic effects of C. ficifolia fruit extract in rats with streptozotocin-induced experimental diabetes. Findings from this study demonstrate that C. ficifolia fruit extract has been shown to have, besides hypoglycemic properties, strong hypolipidemic action on diabetic hypertriglyceridemia and hypercholesterolemia as well. Therefore, consumption of C. ficifolia fruit as a therapeutic diet may be useful in the treatment of diabetes.     

RELATIONSHIP BETWEEN VISCOSITY AND FAT CONTENT OF MILK AND CREAM

A comparison of the published data on the flow behaviour of milk and cream at higher shear rates reveals conflicting results which can be explained partly by differences in experimental conditions. Among others, cold agglutination and churning effects appear to play a role. In the absence of these effects and at not very low shear rates, milk behaves as a Newtonian liquid. Excellent agreement is obtained between measured viscosity (η) as a function of fat content (ø f ) and theoretical relations between η; and the volume fraction of dispersed particles, but only if the volume occupied by the protein particles and sugar molecules in the milk is taken into account.     

COLORIMETRIC CHARACTERIZATION OF EGG YOLK AND EGG YOLK PRODUCTS

Procedures are suggested for COLOR-EYE® evaluation of various yolk forms and products. Chromaticity coordinates derived from COLOR-EYE determinations and the calculated dominant wavelength (λ_d), excitation purity (P_e) and luminous reflectance (Y_CIE) values were also determined for each yolk form and product analyzed. Characteristics of aged yolks included reduced λ_d and P_e and an increase in Y_CIE values; the greatest effects were at the highest levels of pigmentation concentration. Luminous reflectance values were substantially lowered by the addition of sugar and subsequent frozen storage; all other calorimetric criteria were relatively unchanged. Yolk age effects were negligible for the calorimetric characterization of yolks incorporated into product forms. Mayonnaise products provided the most consistent COLOR-EYE readings. These data suggest the feasibility of utilizing the COLOR-EYE, or similar instrumentation, as an objective method for the color characterization of various yolk products. Numerous options are available for converting data into other desired instrumentation values and terminology.     

磷脂酶A改性的蛋黄功能性质及其对蛋制品品质影响

采用磷脂酶A水解蛋黄中的卵磷脂生成溶血卵磷脂，转化度为80％。研究了磷脂酶A改性蛋黄的功能性质及其对蛋黄酱和面包品质的影响。改性蛋黄功能性实验表明：酶法改性之后的蛋黄比普通蛋黄具有更大的乳化稳定性、吸湿性，以及显著的耐热性。蛋黄酱应用实验表明：相对普通蛋黄制作的蛋黄酱，酶法改性的蛋黄制作的蛋黄酱黏度是其1．5倍，而且改性蛋黄制作的蛋黄酱可经受100℃，30min的热处理而不会有油析出。面包应用实验表明：改性蛋黄制作的面包具有更高的综合评分，比普通蛋黄对面包具有更好的抗老化效果。     

EFFECT OF DIETARY FIBER ON THE PREVENTION OF LIVER LIPID ACCUMULATION INDUCED BY HIGH POLYUNSATURATED OIL

This study investigated whether dietary fiber can prevent the accumulation of liver lipids due to the ingestion of polyunsaturated oil. Fifteen percent fish oil (FO) was added to the basal diet as a source of polyunsaturated oil. Ten percent cellulose, pectin, guar gum, konjac mannan or gum Arabic was mixed in the diet as a source of dietary fiber. Commercial Purina rat chow was used as a control and a fiber-free (blank) diets were also employed in the study. Each experimental diet was fed to each group of 6 Wistar rats for 8 weeks. Fish oil feeding lowered the plasma triacylglycerols (TG) and cholesterol (CS) levels. Rats fed a fiber-free diet had higher liver weights indicating hepatomegaly and a marked accumulation of liver lipids. With the exception of cellulose and gum Arabic, the inclusion of dietary fiber in FO diets lowered the plasma total lipids and CS; plasma TG was unchanged. Pectin and guar gum enhanced the CS-lowering effect of the FO diet. All of the test fibers, but especially pectin and guar gum, reduced the accumulation of total lipids, TG and CS in rat liver caused by dietary FO. Hepatic glucose-6-phosphate dehydrogenase activity was reduced in rats fed FO, but dietary fiber had no effect on the activity of this enzyme.     

淀粉基脂肪模拟物的性质及代脂研究

以玉米淀粉为原料，在不同条件下对其进行酸水解制取脂肪模拟物。并对得到的不同DE值（糖液中的还原糖含量占干物质百分率）的玉米淀粉基脂肪模拟物进行性质研究。扫描电镜观察结果表明，样品具有2μm-6μm的粒径；x-粉末衍射图表明，样品保留了A型特征峰。以其中一种脂肪模拟物为代表，作为脂肪替代品加到奶油中进行代脂研究，结果表明所制得的玉米淀粉水解产物可作为脂肪模拟物用于奶油中。     

COMPARISON STUDY OF EGG YOLKS AND EGG ALTERNATIVES IN FRENCH VANILLA ICE CREAM

Egg alternatives may replace egg as a functional ingredient in French vanilla ice cream due to their functional and dietary benefits. These egg alternative ingredients include modified corn starch (MCS), whey protein concentrate (WPC) and soy protein isolate (SPI). The objective of this study was to compare the physical and sensory properties of several commercially available egg alternatives in a vanilla ice cream formulation. The SPI exhibited a significantly lower L value compared with the other egg alternatives, whereas the control exhibited a significantly higher b value compared with the other treatments. The apparent viscosity value of MCS was approximately 10-fold greater than the other egg alternatives. There were no significant differences in appearance and mouth-feel among the control, MCS or WPC treatments, whereas SPI exhibited a significantly lower mouth-feel score compared with the other treatments. The control exhibited significantly higher flavor and acceptability scores compared with the other egg alternatives, whereas SPI treatment exhibited least desirable flavor and acceptability. Consumer panelists would purchase the control with the egg alternative formulations.

PRACTICAL APPLICATIONS

The egg alternatives were used to replace egg as a functional ingredient in French vanilla ice cream production. These alternatives can deliver functionality at a lower cost and can be incorporated to produce a suitable ice cream.