Incorporation of polyphenolic peanut skin extracts and oregano essential oil into frankfurter-type sausage: effects on properties and shelf life

The objective of this work was to study the effect of the addition of polyphenolic peanut skin extracts (PSE) and oregano essential oil (OEO) on the microbiological, chemical, and sensory properties of frankfurter-type sausages during storage. Seven treatments were prepared: control sample (C: without additives); sausage with commercial additives (F); with OEO (O); with Runner PSE (R); with Virginia PSE (V); with OEO and Runner PSE (OR), and with OEO and Virginia PSE (OV). Consumer tests and general composition analysis were performed on the fresh products (sausages without storage). Sausages were stored at 4 °C during 37 days and samples were extracted at days 0, 12, 23, and 37 for microbiological, chemical (peroxide value and conjugated dienes), and sensory descriptive analysis. All sausages had low fat content (3.36 g/100g) and good colour, flavour and texture acceptance scores by consumers (between 57 on a 9-point hedonic scale). The absence of commercial additives (nitrite, nitrate, and other compounds) affected the sausage characteristic colour, reducing the consumer’s acceptance. The treatments with natural additives had less microbiological and chemical deterioration compared to control sample. The results suggest peanut skin extracts and oregano essential oil can replace commercial additives as preservatives in sausages.