## 1 Introduction  
Sausages are commonly distinguished by the temperature treatment during processing and thus can be designated as dry or cooked [1]. Cooked sausages represent a large group of heat-treated meat products with different organoleptic properties. Cooked sausages are mainly made from beef and pork and other ingredients such as adipose tissue, pork skin, organs, water, spices, and extenders such as starches and flours with additives (salt, phosphates, citrates, ascorbates, nitrite, glutamate, lactates, and glucono-delta-lactone) [2, 3]. Due to different ingredients, heat treatments, and storage times, cooked sausages are prone to chemical, microbiological, and sensory deterioration [4, 5].  
Traditional Croatian cooked sausages are mainly produced from low-quality pig meat, pig offal (liver, heart, lungs, etc.), skin, blood, and other ingredients. \"Bijela krvavica\" is a traditional Croatian cooked sausage produced from cooked pig head tissue, cooked pig heart, cooked pig tongue, and cooked pig skins, salt, and spices (red paprika powder, hot paprika powder, garlic, and black pepper) [6].  
Trends in the food industry demand the incorporation of plant-based materials into foods, even in meat products. Even though meat is an excellent protein source, and is highly nutritious, it is also poor in fiber content. Thus, numerous investigations have been conducted in order to incorporate various plant waste materials into meat products, many of which are described in [PERSON] et al. [7] and [PERSON] et al. [8]. [PERSON] and [PERSON] [9] reutilized apple pomace as a functional ingredient in buffalo sausages to serve as a source of fiber. In a review by [PERSON] et al. [8], the authors described the addition of soluble dietary fibers to meat products and how it affects the texture of such products. Similarly, [PERSON] et al. [10] added different shares of spent grain flour to smoked sausages. The result was nutritive added value, while the sensory analysis showed liking for samples with up to 5% BSG powder.  
Brewers' spent grain (BSG) along with spent hops, and spent yeasts are the most important byproducts of beer production [11]. BSG is the most important beer industry byproduct with an amount of about 85% [11]. The world beer industry produces about 39 million tons of BSG per year, of which the EU produces 3.4 million tons. It is produced all year by large and small breweries. BSG mainly consists of husks (pericarp seed layers) from the original barley grain with a small amount of starch (depending on the mashing efficiency) and walls of empty aleurone cells. BSG is a lignocellulosic material, which mainly consists of fiber (hemicellulose and cellulose), protein, and lignin [12; 13; 14].  
During the production of 1 hL of beer, about 21-22 kg of BSG, containing 70 to 80% water, is obtained. BSG in this form is mostly used as cattle feed. Due to its moisture and polysaccharide content, it is susceptible to microbiological spoilage. The most used methods for BSG preservation are oven-drying, freeze-drying, freezing, and the use of superheated steam [11].  
These methods for BSG preservation are energy-consuming and result in high costs [7]. Fresh BSG sells for about EUR 35 per ton, while dry BSG achieves a price of about EUR 400 per ton [15]. The use of chemicals (lactic, acetic, formic, and benzoic acids) to prolong the shelf life of BSG is also an option but they are not positively perceived by consumers [11].  
Since drying BSG is time- and energy-consuming, the utilization of wet BSG would be more economical. Plus, this would add value to the nutritive score of meat sausages and keep up with the trend of replacing meat raw materials with environmentally friendly plant waste materials. Thus, the aim of this research was to investigate the possibility of the utilization of wet BSG for the production of \"bijela krvavica\", a traditional Croatian cooked sausage.