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The aim of this research was to examine the possibility of phosphate replacement in all-beef model system emulsions containing 0.3 % of phosphate (CON) with 0.3 % and 0.6 % of dietary fibre of various plant origin, namely, wheat (treatments WH3, WH6), maize (CN3, CN6), pea (PA3, PA6) and potato (PT3, PT6). The pH values of all treatments were similar (6.12–6.27) and corresponded to emulsified-type meat products. Phosphate replacement by fibre led to higher cooking loss (CL) values, from 1.29 (CN6) to 2.43 (PT6) times, not significantly only in CN6 and PA6. Increment in the fibre content led to a significantly lower CL only in the case of maize fibre. On the other hand, all treatments with dietary fibre had significantly lower fluid release under pressure compared to control, while the influence of different fibre types and increase in fibre content was not observed. WH6, CN3, CN6 and PA3 had significantly higher lightness, while all treatments, except for WH6 and PA6, had significantly higher redness. Yellow tones were similar within all treatments. Texture parameters were affected by phosphate replacement with dietary fibres, as hardness and chewiness were higher, while springiness and cohesiveness were lower. No effect of the type of fibre or its level was observed.

The stability of comminuted products plays an important role in the economy of meat industries. Proper formulation and the establishment of suitable emulsification conditions can significantly contribute to cooking losses control. The purpose of this research was to study the relationship between light backscatter parameters and cooking losses and develop prediction models that would allow the optimization of the emulsification process in a continuous industrial emulsifier. The optical response of meat emulsions, produced at industrial scale, depended drastically on the formulation (with and without starch) and the degree of emulsification. Furthermore, formula with starch showed significantly lower cooking losses than formula without starch, but for both formulas, several optical parameters correlated with cooking losses. Models for the prediction of cooking losses with R2 values > 0.999 were obtained with five or six statistically significant optical predictors depending on the formula. These results point out the potential of light backscatter technology as a control tool during emulsification.

This study presents a novel non-destructive X-ray technique for analyzing meat emulsions before and after heat treatment. The method is based on X-ray grating-interferometry where three complementary imaging modalities are obtained simultaneously measuring the absorption, refraction and scattering properties of the sample. Enhanced contrast capabilities of this X-ray technique makes studies on materials with similar attenuation properties possible. The emulsion samples were imaged both in a raw and cooked state. Additionally, different fat types were used in the emulsions in order to compare microstructural differences when either pork fat or sunflower oil was added. From the reconstructed tomograms the different constituents in the emulsions were segmented using a multivariate segmentation method. From this, a quantitative analysis was performed between the different samples, determining properties such as percent object volumes, porosity, average structure thickness and cooking loss. The grating-based X-ray technique and multivariate segmentation made the analysis of the microstructure possible which further gives insight to how both heat treatment, and the use of different lipid types, affect the final protein network quality. Industrial relevance: Meat emulsions have previously been thoroughly studied, and the use of various fat substitutes and protein stabilizers has been investigated. The grating-based multimodal X-ray tomography method presented here is a feasible method to investigate the microstructural changes induced by heat treatment. It provides high-resolution three dimensional spatial information and in contrast to 2D imaging methods, quantitative parameters can be extracted by image analysis for the entire sample volume. Additionally, the non-destructive method allows for imaging the same sample before and after cooking.

The effects of plasma protein (PP) and soy fiber (SF) content on the properties (binding properties, color, and texture) of bologna sausages as influenced by fat level (F) were assessed by response surface methodology (RSM). Higher soy fiber and plasma protein contents favored the formation of harder, chewier structures with improved fat and water binding properties. Fat reduction decreased textural properties and increased weight loss. Cooking loss was affected (P < 0.05) by interactions between PP and F and chewiness was affected (P < 0.05) by interactions between SF and E Plasma protein influenced binding and textural properties more than soy fiber and was, therefore, thought best to limit the effect of fat reduction.

The effects of fat (7.0, 14.0 and 20.0%), starch (0, 5 and 10%) and egg white (0, 1.5 and 3%) on the microstructure and texture of bologna sausages were examined. As levels of fat and starch increased, the microstructure exhibited increasing numbers of holes (P<0.05), smaller in size (P<0.05) and similar (P>0.05) in shape. No clear relationship was found between addition of egg white and these morphological variations. Low-fat sausage (7.0%) was less hard and chewy (P<0.05) than high-fat (200%) sausage; likewise, a direct relationship was found between starch and egg white content and hardness and chewiness of the bologna.