Application of Raw and Defatted by Supercritical CO₂ Hemp Seed Press-Cake and Sweet Grass Antioxidant Extract in Pork Burger Patties

Abstract

Received: 29 May 2021; Accepted: 12 August 2021; Published: 16 August 2021.There is an increasing tendency toward the application of plant origin ingredients in meat products. This study evaluates the physicochemical properties and oxidative stability of pork burger patties produced with the addition of dried raw and defatted by supercritical CO2 extraction hemp seed press-cake as protein-rich ingredients (1.5–2.0%) and sweet grass ethanolic extract (0.5%) as a strong natural antioxidant. The main aim of using such a combination was to assess the possibility of mitigating the negative effects of hemp seed press-cake, containing approx. 10% of highly unsaturated oil, on the oxidation of meat products. The patties were compared with the control sample (without additives) during storage on days 0, 4, 8, 15, and 21 at 4 °C in modified atmosphere conditions. Plant ingredients reduced the lightness of pork patties, while their effects on other physicochemical characteristics were insignificant. The patties with fully defatted hemp seed flour showed the lowest grilling losses. Based on the measurement of thiobarbituric acid reactive substances, raw hemp seed press-cake increased the oxidative rate of pork patties; however, remarkably, the addition of sweet grass extract completely inhibited oxidation during the whole period of storage. The sensory characteristics of the products were acceptable; however, the patties with sweet grass extract received lower evaluation scores.Funding: This study was supported by the European Union’s Horizon 2020 research and innovation programme project ERA Chair for Food (By-) Products Valorisation Technologies of Estonian University of Life Sciences—VALORTECH (grant agreement No 810630); by the Estonian Ministry of Education and Research programme “Support for research and development on resource valorization”, ResTA focus theme “Food: Innovative valorisation of food and food ingredients“ research project, and RESTA28 “Valorization of cereal and oilseed crops”; and by the Estonian Agricultural Registers and Information Board, Innovation cluster MTÜ Liivimaa Lihaveis (project number 616116780016)