"Effect of hydrocolloids on rheological behaviour and sensory characteristics of plant-based sausage analogue."

Abstract

Rheology is a science studying the flow, deformation and fracturing of a material. For a general understanding, this science is utilised to predict how a certain material will behave under certain conditions; in other words, the aim is the characterization of a material. (Wahlkrantz, 2020)
This characterization is used to describe the elastic behaviour and the flow behaviour of a material. The elastic behaviour is evaluated in the case of samples showing elasticity, as for gels. The flow behaviour involves the viscosity parameter and is therefore used to characterize fluids.
Due to higher request of plant-based options in the market by the consumers, the food industry is developing more vegetarian and vegan products like meat analogues. These products are often formulated with plant-based extruded or isolated proteins and hydrocolloids like carrageenan
The aim of this study is to perform a rheological characterization of the tested samples, containing a base sausage vegan mix, and different types of carrageenan.
In this project, the elastic properties and the flow behaviour of both cooked and uncooked plant- based sausage formulations containing carrageenan was evaluated.
It was found that upon heating treatment, the sample showing overall higher rigidity and elasticity was the one containing iota carrageenan. The non-cooked sausage slurry showed a shear thinning pseudoplastic behaviour with no shear stress but rather a zero stress viscosity plateau at the beginning of the flow. The highest viscosity within the uncooked samples was shown by iota carrageenan. Processed Eucheuma seeds samples showed the worst structure after the heating process, as well as lowest viscosity before being cooked. With a general high texture profile iota carrageenan showed the best results in this study, therefore its application in future plant-based sausage formulations is the most promising compared to all the types of carrageenan tested.

Popular Abstract

This study is aimed to evaluate the gelling properties of different types of carrageenan and how they are connected to the sensory characteristics of a plant-based sausage formulation containing pea proteins.
It is well known today that we should reduce the consumption of animal proteins and especially red and processed meat, not only for our health but also for the environment. As a result of this common thought, more and more people are switching to a vegan or vegetarian diet, and even meat- eaters are trying to reduce their weekly meat intake. For this reason, the food industry is developing more plant-based options like meat analogues and meat substitutes, as the request of these products in the market is raising.
Mimicking both the consistency and the taste of meat can be challenging, and different industrial processes can be applied for this purpose. In this study a plant-based formulation has been used, containing pea proteins. This mix has been combined with different types of carrageenan: two types of kappa carrageenan, one type of iota carrageenan, a combination of kappa and iota and two different types of processed Eucheuma seaweed. The different combinations resulted in different elasticity within the final product and different viscosity within the uncooked mixes, as well as different texture.
The cooked plant-based sausages, characterized as viscoelastic, belong to the category of soft solids. Iota carrageenan was the type of carrageenan which showed overall highest gel strength and elasticity within the types of carrageenan analysed. A high elasticity was shown also by the samples containing kappa carrageenan type 1 and the combination of kappa type 1 and iota, although with more stiffness compared to iota. The uncooked plant-based sausage mixes containing carrageenan started to behave like fluids at minimum forces applied over them, characteristic placing the mixes in the shear thinning and pseudoplastic type of flow, since they did not show a clear shear stress point at the tested shear ranges. The highest viscosity resulted from the samples containing iota carrageenan, while the lowest was shown by Processed Eucheuma seaweed type 2. The highest syneresis was observed on the samples containing kappa carrageenan type 1, while the lowest yield losses were found in kappa carrageenan type 2 sample. An overall favourable texture was observed for the samples containing iota carrageenan, making this sample the one which could show the most promising results in future plant-based sausage formulations with the base mix used in this study.
More studies need to be performed to profile the viscoelasticity of the samples upon cooling, after the cooking process. This would be helpful to observe any changes in the gel strength when the structure tightens up, since the samples are normally cooler than 85°C (final heating temperature
point used in this study) at some of the final processing steps and also when they are about to be eaten by the consumers. Therefore, observations upon the setting temperature of the gels might be of interest both for the industrial sake and for the consumer acceptability.
This project did not involve the use of spices in the mixes. Adding the spices would definitely affect the final texture, as adding up more powders in the formulation might increase the hardness of the samples too much resulting in an unpleasant mouthfeel. Therefore, more texture analysis needs to be done in order to test further the consumer acceptability of product, perhaps paring it with a panel test to assess the carrageenan type working best for future formulations.

• author: Rinaldi, Simona
• supervisor: Lars Nilsson
• organization: Food Technology and Nutrition (M.Sc.)
• course: KLGM01 20221
• year: 2022
• type: H2 - Master's Degree (Two Years)
• subject: Agriculture and Food Sciences
• keywords: rheology, plant-based, sausage analogue, food technology
• language: English
• id: 9090925
• date added to LUP: 2022-06-21 09:42:13
• date last changed: 2022-06-21 09:42:13