A Comparison of Some Properties of Meat from Young Buffalo (Bubalus bubalis and Cattle

Meat properties of four muscles of differing collagen content from both Achilles tendon-hung and tenderstretched (suspended from the sacrosciatic ligament) sides of water buffalo (Bubalus bubalis) and Brahman-cross steers were assessed. The animals were together on good pasture until slaughtered at similar ages (27 months) and liveweights (ca 317 kg). Buffalo muscles were darker than beef and darkened more at chill temperatures. Warner-Bratzler peak force minus initial yield values, adhesion and compression values indicated that for the three muscles with the greater connective tissue contents, buffalo muscles were slightly tougher than corresponding beef muscles because of a greater contribution of connective tissue to toughness. No species differences were found for the psoas major muscle except for flavor, where beef was slightly preferred.     

FULLY DEVELOPED LAMINAR CONVECTION FROM A HELICAL COIL

A general correlating equation has been developed for all Prandtl and Dean numbers. This expression was constructed by joining the theoretical Nusselt number for a straight tube, a theoretical asymptote for the regime of creeping secondary flow, a semi-theoretical expression for the boundary layer regime and an asymptotic value of Nu for the intervening regime of flow.The arbitrary coefficients and exponents in the model were evaluated using experimental and numerically computed values. Slightly differing sets of coefficients are required for uniform wall temperature and longitudinally uniform heating with uniform peripheral wall temperature.

All prior theoretical results were for toroidal flow (zero pitch). A numerical solution was developed for helical flow (finite pitch). These results confirm the validity of neglecting pitch for tightly wound coils but suggest a generalization of the correlating equation for large pitch.     

CHANGES IN QUALITY CHARACTERISTICS DURING PEACH (CV. ‘MAJESTIC’) MATURATION1

Changes in the physical, chemical and sensory characteristics of peaches (cv. ‘Majestic’) were determined. Size, weight, ground color “a” values and SS/TA ratio increased significantly with increased degree of maturity; whereas, firmness, DLE, hue angle, titratable acidity, quinic acid, and citric acid decreased significantly. Malic acid increased significantly with maturity up to grade 5 then significantly decreased. In general sucrose content and total sugars increased through grade 6 and then decreased for tree ripe fruit. Sensory evaluation results showed no significant differences among maturity grades for sweet, sour, juice and overall peach flavor attributes. However, grade 1 and 2 fruit had lower scores for sweet and overall peach flavor attributes and tended to be more sour than grades 3–6 and tree ripe fruit. Correlation coefficients between maturity grade and all the selected quality parameters, except for the sour flavor attribute, were significant at the 1% level. DLE had the highest correlation with maturity grade followed by ground color “a” value, SS/TA ratio and firmness.     

Mechanisms of Groundwater Pollution by Pesticides

An increasing number of pesticide compounds are being detected in groundwater supplies worldwide. There has, nevertheless, been little research into the mechanisms by which such pollution occurs and the routes via which pesticides move from the land surface into aquifers. In view of the potential time-lag in the response of groundwater systems to pollution inputs, such knowledge is essential if the current situation is to be appraised adequately and if any necessary controls on pesticide use are to be introduced.
From basic data on the physicochemical properties of pesticide compounds and on groundwater flow and pollutant transport in the principal British aquifers, some useful observations can be made about the relative significance of different mechanisms of potential groundwater pollution. These mechanisms and their implications for field research on pesticide pollution of groundwater are discussed. This problem is compared and contrasted to that of nitrate pollution from agricultural land-use practices.     

Low-fat Margarine Spreads as Affected by Aqueous Phase Hydrocolloids

The effects of gelatin, maltodextrin, modified starch, sodium alginate and sodium caseinate on the physical, structural and sensory properties of low-fat spreads were systematically evaluated. Stability at 34°C and stability on centrifugation decreased, while microscopy revealed an increase in aqueous phase droplet size and more open emulsion structures after inclusion of hydrocolloids. These effects were accompanied by changes in sensory (texture and flavor) properties, with the spreads becoming less waxy/greasy but having faster, more intense flavor characteristics after addition of hydrocolloids. Gelatin and maltodextrin had a slight effect, modified starch and sodium alginate were intermediate and sodium caseinate had the greatest destabilizing effect on structural characteristics of the emulsion.     

OBSERVATIONS ON TEXTURE MEASUREMENT OF RAW CUCUMBERS WITH THE FRUIT PRESSURE TESTER*

Raw fruit of a ‘firm’ (Explorer) and a ‘soft’ (Green F) cucumber cultivar were puncture tested with the Magness-Taylor fruit pressure tester (FPT) manually, and also with the FPT or only FPT tip mounted in the Instron. Puncture-values for flesh only were 70–75 % of those for intact fruit. Neither the cucumber size (1–2.5 in. diam) nor the test speed (5–50 cm min^-1) appreciably affected the puncture test values.     

EVALUATION OF DIETARY FIBER IN POTATO CRISPS: INFLUENCE OF THE ANALYTICAL METHOD USED

Dietary fiber in ready salted potato crisps was determined by two methods, i.e., the official AOAC method, and the modified method of Englyst, recommended in the U. K. The ultimate aim was to compare the results and to evaluate the advantages and limitations of each method for the analysis of this food in order to obtain a figure to be included on the package. The AOAC method is an enzymatic-gravimetric procedure to determine the total dietary fiber (TDF). The Englyst method consists of an enzymatic-chemical extraction and fractionation of the nonstarch polysaccharides (NSP) and their subsequent determination as neutral sugars by GLC. We modified the original chromatographic method. The AOAC method gave a value of 5.39 g/100g (dry matter) for TDF, and the Englyst method of a value of 1.70 g/100g (dry matter) for NSP. It is assumed that the gravimetric method gives a higher fiber value than the Englyst method due to a contribution from retrograded starch. For this particular food, the AOAC method is faster and much easier to carry out and does not overestimate dietary fiber, if the resistant starch is regarded as part of it.     

INCIDENCE OF CAMPYLOBACTER IN PROCESSED POULTRY: IS IT A CONCERN FOR HUMAN HEALTH?

In Australia, over 15,000 cases of campylobacteriosis occur annually; however, recent findings from case-control studies suggest that poultry may not be the primary etiological agent. To determine the incidence of Campylobacter species on Australian poultry, a qualitative and quantitative survey of different poultry products was undertaken. The qualitative study examined 428 poultry carcasses from 42 processors. Overall, 93.7% of the carcasses were found to be positive for Campylobacter species, of which 84.1% were identified as Campylobacter jejuni by hippurate hydrolysis, and 9.6% as other Campylobacter species. A longitudinal study over 6 weeks on 27 broiler carcasses from a single processor found an average Campylobacter species count of 163 cfu/cm², with a range of 5–1,850 cfu/cm² excluding one carcass that was negative. The real health risk of this carriage, however, cannot be determined accurately without further investigation of the presence of virulence factors and more accurate species identification.

PRACTICAL APPLICATIONS

This article identifies that the incidence of Campylobacter species on processed poultry remains at levels recognized to be potentially infectious to humans. This suggests that current changes in processing control in the Australian poultry industry primarily established for Salmonella species may not necessarily reduce all potential human pathogens to safe levels.
Using current literature, this article also debates whether the simple identification of presence and absence of a particular pathogen is sufficient for assumptions to be drawn on risk of infection. The discussion questions the real role of poultry in cases of campylobacteriosis, and suggests that based on case-history data, poultry may be not be the common cause of the disease.