Effect of nordihydroguaiaretic acid on luteal phase length and oxytocin-induced release of prostaglandin F2 alpha in heifers

Two experiments were conducted to determine if intrauterine infusion of nordihydroguaiaretic acid, a lipoxygenase pathway inhibitor, would delay luteolysis (Experiment 1) and inhibit oxytocin-induced release of prostaglandin F2 alpha (as measured by the stable prostaglandin F2 alpha metabolite, 15-keto-13,14-dihydroprostaglandin F2 alpha) in plasma on d 16 (d 0 = estrus) of the estrous cycle (Experiment 2). Nordihydroguaiaretic acid (20 mg) or saline was infused twice daily into the uterus on d 14 to 23 (Experiment 1) or d 14 to 20 (Experiment 2) postestrus, respectively. In Experiment 1 and 2, mean concentration of progesterone was higher and luteolysis was delayed in nordihydroguaiaretic acid-infused heifers compared with saline-infused heifers. In Experiment 2, saline or oxytocin (100 IU, i.v.) was injected into each heifer on d 16 postestrus to stimulate the release of prostaglandin F2 alpha from the uterus. Mean concentration of 15-keto-13,14-dihydroprostaglandin F2 alpha increased within 1.5 h postinjection in heifers infused with saline, whereas concentration of 15-keto-13,14-dihydroprostaglandin F2 alpha in nordihydroguaiaretic acid-infused heifers did not increase within the same time period. Thus, nordihydroguaiaretic acid may inhibit both the lipoxygenase and cyclooxygenase pathways of arachidonic acid metabolism and therefore delay luteolysis.     

Modified atmosphere packaging of seafood

The shelf life of seafood under current icing and refrigerated storage conditions ranges from 2 to 14 d, depending on species, harvest location, and season. Elevated carbon dioxide levels in modified atmosphere packaging (MAP) has been shown to inhibit the normal spoilage flora of seafood and double or triple shelf life. The threat of botulism, due to the presence of nonproteolytic psychyrotrophic Clostridium botulinum types B, E, and F, has been reason for caution in expanding this technology. This article examines the safety of MAP seafood through analysis and comparison of raw materials, research methodologies, quality indices, treatment, and packaging options.     

Characteristics of the nutrition of the male population of Ufa

The method of daily ration reproduction was used to study the actual nutrition of 25% of male subsampling comprising 674 subjects, during the epidemiological investigation of unorganized male population in a region of Ufa. The results of the study have shown that the caloric value of their nutrition does not exceed the established standards and is diminished with age. Protein consumption meets the physiological requirements, animal proteins prevail in their structure. Carbohydrate consumption is low, mainly at the expense of starch, while the share of sugar is high. Fat consumption exceeds the values recommended, mainly at the expense of saturated fatty acids. Cholesterol consumption is excessive. The established nutrition imbalance of the main food substances has evidenced the atherogenic character of the population nutrition, prevalence of animal food products in its structure, that should be taken into consideration when measures for the prevention of coronary heart disease are elaborated.     

Effects of Salt, Sugar and Screw Speed on Processing and Product Variables of Corn Meal Extruded with a Twin-Screw Extruder

The effects of screw speed and additives (sugar and salt) on processing and product variables of corn meal extruded with a twin-screw extruder were studied. Higher salt (0–3%) and sugar concentrations (0–4%) in the feed decreased the die pressure, % torque and specific energy. But at 6 and 8%, sugar increased the three processing parameters. Higher screw speed (250 vs 200 rpm) decreased die pressure and % torque, but increased specific energy. The addition of salt and sugar enhanced extrudate radial and axial expansions, but reduced product bulk density and breaking strength. An increase in screw speed decreased radial expansion and bulk density, but increased axial expansion and breaking strength.     

Baking Properties of Bread and Cookies Incorporating Distillers' or Brewer's Grain from Wheat or Barley

The effect of granulation, level of soluble solids, and drying method on the mixing properties and baking performance of distillers’grain products from wheat in yeast-raised breads and cookies were evaluated and compared with products containing barley spent grains (BSG). Grinding had a variable effect on baking properties. Breads containing 8% wheat distillers' grains (WDG) (no solubles) had the lowest loaf volume. Breads made with WDG and BSG had the poorest crumb grain. There were few differences observed in the mixing and baking properties of wheat distillers’grains (DDGS or DDG) regardless of whether the materials were dried by harsh (steam tube, tunnel) or milder (atmospheric drum) drying treatments.     

Effect of Water Activity of Milk upon Growth and Acid Production by Mixed Cultures of Streptococcus thermophilus and Lactobacillus bulgaricus

Acid production and growth rates were determined in pure cultures of Streptococcus thermophilus and Lactobacillus bulgaricus and cocci/ bacilli ratios in mixed cultures of both species, using milk with modified a_w as culture medium. Maximal growth rates were always at a_w lower than 0.992 for all strains whcn a_w of milk was adjusted with glycerol, while maximal acid production rates were at a_w 0.992-0.983. Glucose had an inhibitory effect additional to that caused by lowering a_w. The cocci/bacilli ratio in mixed cultures increased as a_w decreased in most cases, because of the higher susceptibility of L. bulgaricus to a_w decrease. The behavior of a mixed culture could not always be predicted from data of the component strains in a pure culture, showing some kind of symbiotic compatibility between species.     

Evaluation of the Physical, Chemical and Sensory Properties of Fermented Summer Sausage Made from High-Oleate Pork

The processing, visual and sensory characteristics of fermented summer sausage formulated with pork containing varying levels of oleic acid and either 15 or 25% fat was evaluated. Sausage made from the high-oleic acid tissues received lower sensory panel scores for springiness, cohesiveness, texture and overall palatability (P < 0.05). However, low-fat (15%) fermented summer sausages produced from the high-oleate tissues were comparable to the control for sensory and visual characteristics.     

RHEOLOGICAL MODELING of POTATO FLOUR DURING EXTRUSION COOKING

A generalized model for predicting the effects of shear rate, temperature, moisture content, time-temperature history and strain history on viscosity has been evaluated for extruded potato flour doughs. an Instron Capillary Rheometer and a 50 mm Baker Perkins co-rotating twin screw extruder were used to evaluate all effects incorporated in the model, except strain history. the power law model was used to describe shear rate effects in the range 10–10000 s^?1. the generalized model fit observed data for temperatures of 25–95°C and moisture contents ranging from 22 to 50%, wet basis. Since potato flour by its manufacturing process is pregelatinized, it was unnecessary to evaluate the effects of time-temperature history. Strain history was found to have an insignificant influence on the viscosity.     

ORIFICE DISCHARGE COEFFICIENTS FOR POWER-LAW FLUIDS

Orifice discharge coefficients for non-Newtonian (power-law) fluids (5, 7.5 and 10% corn starch solutions) were measured using a closed end pipe with different orifice diameters. Results indicate that orifice discharge coefficients, found to be in the range of 0 – 0.7, are a function of the orifice diameter, fluid velocity in the orifice and the fluid rheological properties (consistency coefficient and flow behavior index). They increase with the fluid velocity, tend to be constant at high velocities and decrease when the consistency coefficient of the solution is increasing. Orifice discharge coefficients are presented as a function of the generalized Reynolds number.     

CHANGES DURING CHEESE CURING

Port-Salut, Gouda and Edam cheeses were analyzed for fat, protein moisture and ammonia evolution during commercial curing (50 days for the first two cheeses and 57 days for the last one). Fat (approximately 33%), protein (approximately 31%) on a wet basis and moisture (between 25 and 37%) content of the cheeses remained practically constant throughout the experiment, while considerable changes were observed for ammonia evolution when analyzed by direct microdistillation and by ammonia sensitive electrode, as well as between whole and defatted samples. Ammonia recovery for the microdistillation method was below the expected value for the 3 cheeses analyzed; the contrary happened with the ammonia sensitive electrode, where higher ammonia values were detected in the whole cheese samples: Gouda, 2089 mg/kg; Edam, 756 mg/kg and Port-Salut, 2857 mg/kg. These data suggest that the use of the electrode can be a useful tool in ammonia determination, avoiding losses during sample preparation, as normally happens during microdistillation that requires defatting.