EJPAU, 2005, Volume 8, Issue 3
Food Science and Technology

“Egbo” a popular Nigerian food made from maize grits was fortified with Vigna unguiculata L. Walp and Cajnus cajan in ratios 1:1 respectively to developed new “egbo” based recipes. The physico-chemical and functional properties, proximate composition, mineral content and organoleptic test were determined. Results showed that in all cases, the level of protein and mineral increased with the inclusion of the legumes. The values obtained for functional properties showed that “egbo” would be suitable for some food formulations. The fortified “egbo” samples were considered acceptable to panelists but the one with Vigna unguiculata L. Walp was preferred.

The emulsifying properties of beta-Lg preparations were dependent on the method the protein was isolated from the sweet whey retentate, protein concentration in emulsion and medium pH. The emulsion stabilized with beta-Lg preparation obtained after salting the protein out with 30% solution at pH 2.0 (beta-Lg 1) had oil droplets with smaller volume surface diameter (d_vs) than the emulsions stabilized with the beta-Lg preparation after alfa-lactalbumin isolation from the whey retentate in mild conditions (55 ^oC/30 min, pH 3.9) (beta-Lg 2). The d_vs value for emulsions was found to decline with an increase in the protein concentration from 0.5 to 2.0% and in the pH value from 5.0 to 7.0. Statistically significant (p ≤ 0.05) decline in d_vs value was found for beta-Lg 2 in the whole range of pH and only at pH 5.0 for beta-Lg 1, for which the increase in the concentration above 1.0% was insignificant (p ≤ 0.05) for d_vs at pH 6.0 and 7.0. The increase in the medium acidity from pH 7.0 to 6.0 and 5.0 increased significantly (p ≤ 0.05) d_vs value only for beta-Lg 1 at the concentration 0.5 to 2.0% and for beta-Lg 2 at the concentration 1.0-2.0% and 0.5% , respectively. Natural fractal dimension (D_L) of particles of beta-Lg preparations were almost the same, i.e. 1.31 and 1.32, and their high value reflected developed surface of the protein particles evidenced on electronograms, what was however unimportant to the emulsifying properties.

In order to establish the influence of branching characteristics on thermal properties of starch hydrolysates, phase transitions of samples differing in content of amylose have been compared. Potato starch dissolved in DMSO/water mixture was hydrolysed by crude pullulanase preparation and fractionated by precipitation. The fractions differed in their branching characteristics and after solubilisation and retrogradation gave endotherms at different temperatures. The results prove that even slight changes in branching pattern can cause significant variation in phase transitions. The solvent system used in the experiments seems to stabilize linear glucans for a long time and promote recrystallisation of branched molecules.

The aim of this study was to assess the range and dynamics of changes in the muscle tissue structure under the influence of the injection and plastification processes, using the macroscopic image computer analysis technique. Ham muscles (m. biceps femoris) were examined fresh, after being injected with curing brine, in the middle of the adopted massaging time, i.e. after 3 h and 20 min (a total of 1200 rotations of the massage machine drum), and after the massaging process was completed, i.e. after 6 h and 40 min of massaging (a total of 2400 rotations of the massage machine drum). The process of plastification caused changes in the structure on the surface of ham muscles, which resulted in an additional binding of the added brine by the muscle protein and facilitated increased extraction of muscle protein outside the muscle. The changes on the surface of the muscles could be observed thanks to the applied computer analysis of macroscopic images.

Changes in textural parameters of selected muscles (m. longissimus lumborum - LL, m. semitendinosus - ST, m. semimembranosus - SM, m. biceps femoris - BF) of pure-breed cattle Charolaise (CHL) and two groups of cross breeds: Hereford×Charolaise (HEF×CHL) and Simental×Charolaise (SIM×CHL) taken on the 3rd, 7th and 12th day of post-mortem cold storage were estimated.

Of the four muscles tested, the highest hardness, springiness and chewiness were found in BF, which at the same time showed the highest stringiness, perceptible of connective tissue, cooking loss, and the lowest juiciness. Post mortem ageing resulted in a reduction of hardness, springiness and cooking loss and in an increase of tenderness and purge loss. The rate and dimension of tenderization were relative to the both cattle genotype and muscle tested on the one side, and stage of tenderization on the other.

The principal aim of this study was to determine technological possibility of utilization of condensed porcine blood plasma containing about 21% of protein for production of "Salami" type raw sausages.

These studies were based on evaluation of dynamic of fermentation changes and sensory quality of final products.

Four variants of blood plasma preparations were applied in the study, it means: fresh condensed plasma, fresh condensed plasma modified microbiologically with addition of lactic acid bacteria cultures mixture, fresh condensed blood plasma modified with addition of liquid smoke preparation and dried blood plasma preparation after its water rehydration to the level ensuring total protein content of 21%.

Sausages were next analyzed for content of lactic acid, total amount of volatile low fatty acids, pH-value, content of ethyl alcohol and their sensory acceptance.

The relationships between analyzed chemical quality characteristics and sensory acceptability of experimental sausages were found.