Driven by the need for trans- and saturated-fat replacement, much research has been done on fat substitutes for food products¹. The excessive consumption of high-fat products has been linked with health problems, such as obesity, cardiovascular diseases, and metabolic syndrome. Bigels are biphasic systems consisting of a hydrogel and an oleogel, that could be utilized as promising substitutes of animal fat, allowing for the reduction of total fat and cholesterol content². However, reducing the fat content in foods and specifically in meat products may result in undesirable sensorial characteristics³.
The objective of the study was to evaluate the properties of oleogel-in-hydrogel bigels and the effect of the 50% substitution of the pork backfat by the bigels in fermented sausages. Bigels were prepared by mixing oleogels structured with 15% monoglycerides and hydrogels structured with 10% gelatin or 10% gelatin plus 1% κ-carrageenan in different mixing ratios (40/60 and 20/80). The textural characteristics and swelling capacity of the bigels were studied. Also, the physicochemical, microbiological, and nutritional characteristics of fermented sausages with bigels were evaluated and compared to control.
Bigels with a higher oleogel ratio exhibited increased cohesiveness and decreased hardness, while the incorporation of κ-carrageenan into the hydrogel led to enhanced hardness. The pH values and the weight losses were higher in fermented sausages with bigels compared to the control. Fat substitution did not affect the microbiological characteristics of the sausages. The finished products with bigels exhibited better nutritional characteristics, showing a decrease in total energy, saturated fatty acids, and cholesterol content.
The use of bigels as pork back fat substitutes in fermented sausages and generally in foods with a high-fat content permits high substitution levels, as the finished products' nutritional characteristics are improved.