Technological and sensorial role of yeast β-glucan in meat batter reformulations

Biotechnological Addition of β-Glucans from Cereals, Mushrooms and Yeasts in Foods and Animal Feed

Varied cereal plants including, mushrooms, yeast, bacteria and algae are important sources of β-glucans, and many extraction procedures have been used in order to recover these valuable naturally occurring polysaccharides. The rheological and molecular properties of β-glucans can be utilized to be incorporated into various foods and to offer properties extremely beneficial to human health. Their functional effects are mainly determined by their molecular and structural characteristics. Consumption of foods fortified and enriched with β-glucans can contribute to the treatment of certain chronic diseases. Reduced cholesterol, cardiovascular and diabetic risk and moderate glycemic response of foods have been recorded with the consumption of these biologically active compounds. In addition, β-glucans are characterized by anti-cancer, antioxidant, anti-inflammatory and antiviral activities. As β-glucans interact with the foods in which they are incorporated, this review aims to discuss recent applications with quality and nutritional results of β-glucans incorporation with foods such as beverages, dairy, bakery, meat and pasta products, as well as their addition in animal feeds and their uses in other fields such as medicine.

Spent Brewer's Yeast as a Source of Insoluble β-Glucans

In the brewing process, the consumption of resources and the amount of waste generated are high and due to a lot of organic compounds in waste-water, the capacity of natural regeneration of the environment is exceeded. Residual yeast, the second by-product of brewing is considered to have an important chemical composition. An approach with nutritional potential refers to the extraction of bioactive compounds from the yeast cell wall, such as β-glucans. Concerning the potential food applications with better textural characteristics, spent brewer’s yeast glucan has high emulsion stability and water-holding capacity fitting best as a fat replacer in different food matrices. Few studies demonstrate the importance and nutritional role of β-glucans from brewer’s yeast, and even less for spent brewer’s yeast, due to additional steps in the extraction process. This review focuses on describing the process of obtaining insoluble β-glucans (particulate) from spent brewer’s yeast and provides an insight into how a by-product from brewing can be converted to potential food applications.

Fat Replacement by Vegetal Fibres to Improve the Quality of Sausages Elaborated with Non-Castrated Male Pork

Simple Summary

Traditionally, male pigs were castrated without anaesthesia or pain relief before they reached 7 days of age to avoid the production of an undesirable odour and flavour in their meat, termed “boar taint.” In recent years, to improve animal welfare according to European recommendations, farmers have generally abandoned this practice, increasing the supply of non-castrated male pork in the market. Based on this, alternatives are required to improve the quality of meat and meat products derived from these animals, as these products also possess different texture characteristics that make the meat harder and less juicy due to the presence of less fat. Recently, health has become more important to consumers, and reducing the fat content in non-castrated male pig products by replacing it with vegetable fibre has been shown to represent a good strategy for masking and improving texture.

Abstract

Based on the need to find alternatives for the use of meat from non-castrated male pigs that contains high levels of androstenone and skatole, the production of meat products (raw and Frankfurt sausages) with reduced fat content was proposed, as these compounds are lipophilic. For this purpose, three batches of each product (total six) were produced. These included a control batch (1); normal fat content and two fat-reduced batches, where (2) fat was replaced with inulin and β-glucan, or (3) fat was replaced with inulin and β-glucan in addition to a skin grape by-product. These groups used meat from non-castrated male pigs that contained 6.25 µg/g androstenone and 0.4451 µg/g skatole. In general, fat-reduced sausages exhibited less brightness than did the controls. The texture results in Frankfurt were similar to those of the control, while Spanish sausage supplemented with grape skin exhibited reduced hardness. Both strategies resulted in a reduction in boar taint, and this reduction was up to 87.3% in raw sausages with grape by-products. Fat reduction could provide an interesting strategy to allow for the use of tainted meat from non-castrated male pigs.

Effectiveness of Oat-Hull-Based Ingredient as Fat Replacer to Produce Low Fat Burger with High Beta-Glucans Content

Low-fat beef burgers with high beta-glucan content was obtained using a gel made from an oat-hull-based ingredient as fat replacer. Two levels of fat substitution were considered: 50% (T1) and 100% (T2). The nutritional composition, cooking yield, textural properties, color characteristics and consumer preference were evaluated, in comparison with a burger without fat replacer (CTRL). After cooking, T2 burger showed a significant increase in the cooking yield and a very low lipid content (3.48 g 100 g^-1) as well as a level of beta-glucans per single portion (2.96 g 100 g^-1) near the recommended daily intake. In T1 burger, the decrease of lipid content was mitigated during the cooking process, because the beta-glucans added had a fat-retaining effect. Compared to CTRL, replacing fat led to a softer texture of cooked burgers evaluated by Texture Profile Analysis. The differences in color, significant in raw burgers, were smoothed with cooking. The consumer evaluation, carried out according to the duo-trio test, highlighted significant differences between CTRL and T2 burgers in terms of odor, taste, color and texture. The consumers expressed a higher preference for the T2 burger, probably due to its softer texture and greater juiciness.