DYNAMIC AND STEADY SHEAR RATE ASPECTS OF MINCED MEAT 'SETTING'

Dynamic and time-dependent steady shear rate properties of minced chicken meat were studied immediately after preparation and following a 24 hr low temperature incubation. Incubation at 3d? C resulted in a significant increase in the storage moduli and a relatively constant decrease in the loss tangent over the range of strain amplitude (0.010-0.126; at an angular frequency of 0.299 s ^-1. The stress relaxation behaviour was retarded and the equilibrium shear stress value was 30% higher when compared with the untreated samples. Time-dependent studies of hysteresis loop areas revealed a significant increase in structure breakdown after incubation. The effects observed after low temperature incubation were ascribed to an intermolecular interaction between myosin A and F-action.     

CAROTENOID TRANSFORMATIONS IN RIPENING APRICOTS AND PEACHES

SUMMARY –β-Carotene was the dominant pigment of apricot tissue and accumulated rapidly during ripening; however, in peach tissue, β-carotene along with lutein and violaxanthin were synthesized in almost equal amounts during the ripening process. In the latter tissue small amounts of zeaxanthin were detected mid-point in the ripening sequence. Peach and apricot tissue incorporated [2-¹⁴ C] mevalonic acid into β-carotene, β-cryptoxanthin, lutein and also into violaxanthin in peach tissue. Incorporation of [2-¹⁴ C] mevalonic acid into the above carotenoids was greatest during the initial stages of ripening in the peach and then declined with senescence especially in the xanthophylls lutein and violaxanthin.     

DISCUSSION OF THE BINDING QUALITY OF MINCED MEATS BASED ON THEIR RHEOLOGICAL PROPERTIES BEFORE AND AFTER HEATING

Abstract Raw fish meat and three muscle groupings of cockerel meat were analyzed for total nitrogen, myofibrillar and sarcoplasmic proteins, non-protein and residual nitrogen, fat, pH, moisture and hydration capacity. Stress relaxation measurements were made on both raw and heat coagulated samples. Tensile strength measurements were made on heat coagulated samples. Using breaking energy as an index of binding, myofibrillar protein content and hydration were tentatively related to binding quality. Equilibrium modulus values offered an indication of the presence of crosslinking after heating. The rheological behavior of fish meat could be explained by a seven element model and that of cockerel meat by a five element model before heating. An analysis is presented of the mathematical treatment of rheological measurements and their relationship to binding quality and chemical composition of the tested samples.     

增效成分对桐酸酯用于仓贮害虫防治时的协效作用

中日合作研究了增效成分对桐酸酯类系列品种对玉米象的防治效果。试验表明含增效成分的桐酸酯对玉米象具有明显的致死效果,致死率为70％～87．5％,未添加增效成分的处理致死率只有2．5％～5％。不含增效成分的桐酸酯处理玉米象的平均产卵数是含增效成分处理的2～3倍,含增效成分的桐酸酯具有明显抑制害虫产卵的作用,对卵的羽化具有完全的抑制作用。     

Multiplier method and optimal control problems with terminal state constraints

The multiplier method for constrained optimization problems is considered geometrically with the concept of supporting hypersurfaces. This geometric interpretation simplifies the comparison of the multiplier method with other existing methods and provides a basis from which to develop new algorithms. Moreover, though it is proved that the algorithm of the multiplier method can be derived from different viewpoints, the convergence of the multiplier method as a successive approximation algorithm is verified in this paper. Finally, the multiplier method is applied to optimal control problems with terminal state constraints, and some numerical experiments are presented.     

RELATIONSHIPS BETWEEN BINDING QUALITY OF MEAT AND MYOFIBRILLAR PROTEINS V. Effect of 'Setting' and Pyrophosphate on Rheological Properties of Heated Minced-Meat Gel

‘Setting’ was observed in minced hen meat stored with 3.5% wt/wt added NaCl. When gels were made from the ‘set’ sol the breaking energy was greatly increased and the relaxation modulus was characterized by a wide ‘quasi-equilibrium’ region. The effect of added pyrophosphate on the rheological properties of the gel prepared at pH 6.0 from ground ‘set’ sol was very similar to that previously observed for ATP in gels prepared at pH 6.0 from ‘unset’ sols. When pyrophosphate or ATP were added at pH 7.0 to the ‘unset’ minced meat sol, the strain at the breaking point and the ratio of the equilibrium to the instantaneous modulus of the heated gel were increased. A comparison with previous results from a model system suggests that pyrophosphate brings about a change in gel structure by dissociating ‘myosin B’ into myosin A and F-actin.     

Free radical reactions in beer during pasteurization

Oxidative reactions during beer pasterization were studied using chemiluminescence (CL) and electron spin resonance (ESR) analyses. the CL production of beer was acclerated by pasteurization and the maximum CL intensity appeared sooner than that in non-pasteurized beer. Beers pasteurized with 15–30 pasteurization units (P.U) had the same CL producing activities as the non-pasteurized beers stored at 20°C for 6–10 days. Free radicals were produced and some of them were consumed by beer oxidation during pasteurization. It seems that free radicals were consumed by beer oxidation during pasteurization. It seems that free radical reactions occur in beer during pasteurization and that the degree of oxidation during pasteurization generally corresponded to that of non-pasteurized beer stored at room temperature for about 1 wee.