3.3.3. Texture Analysis

Textural properties of grilled sausages can be useful in the development of a new product because those are the final textural attributes at the moment of consumption. The texture parameters of raw and cooked longanizas are shown in Figure 4. Raw longanizas exhibited similar (*p* < 0.05) KSF values but significant formulation-related differences were observed in cooked samples. KSF values increased for all samples as a result of cooking (Figure 4). Cooked samples made with all-animal fat (P-NF and P-RF) showed higher (*p* < 0.05) KSF values than those made with EGs (Figure 4). This could be related to the fact that normal and reduced-all-animal fat samples showed the highest (*p* < 0.05) weight loss from cooking (Table 1). It has been suggested that higher cooking losses may result in meat products that are more rigid and less easily broken in binding evaluations [35]. Similar textural behavior in terms of increased hardness from cooking was observed by other authors in fresh meat products such as patties reformulated using emulsions and bulking agents as animal fat replacers to improve their fat content [36,37].

**Figure 4.** Kramer shear force (KSF, N/g) of raw and grilled cooked longanizas. For samples denominations, see Figure 1. Different letters (a, b, c), for the same treatment of samples (raw or cooked), indicate significant differences (*p* < 0.05) between different formulations (P-NF, P-RF, C-RF and O-RF). Different numbers (1,2) indicate significant differences (*p* < 0.05) between formulations and treatments for each type of sample.

#### 3.3.4. Lipid Oxidation Stability

It is well known that thermal treatments such as grilling on an electric pan may accelerate lipid oxidation in meat products, promoting the development of off-flavors and the formation of potentially hazardous compounds. Moreover, high unsaturated fatty acid content, as found in the reformulated sausages used in this study (Figure 2), renders products more susceptible to lipid oxidation [38]. In this context, lipid oxidation levels of raw and grilled longanizas are shown in Table 2. Among raw samples, sausages with all-animal fat showed the highest (*p* < 0.05) lipid oxidation, while no significant differences were observed between reduced-fat samples. Cooking did not affect lipid oxidation in P-NF samples but in reduced-fat samples, it caused lipid oxidation products to accumulate (Table 2). However, the type of fat present in reduced-fat samples affected their oxidation stability and after cooking, those with oat EG (O-RF) showed the highest TBAR values (Table 2). This behavior may be related to the presence of beta-glucan in these samples as it has been shown that the oxidation process of β-glucan is fast at elevated temperatures (85 ◦C) [39]. Given their composition, lipid oxidation levels in the samples prepared with chia EG (C-RF) were unexpected in comparison with all-animal fat samples. In fact, C-RF even had higher PUFA levels than its all fat counterparts. This could be related to the higher levels of antioxidant compounds in chia seed [40]. Several studies have shown that oxidation caused by thermal treatment is very common in meat products that have been reformulated with lipid materials rich in unsaturated fatty acids [41–43].
