A study on the impact of dehulling, germination and fermentation on the technological properties of grey pea flour

Abstract

Grey peas are a forgotten grain seed in the Nordic countries as well as Sweden, which are quite unexplored for their potential uses in different food products. Before the cultivation of yellow peas and green peas took over, they used to be the dominating type of peas in Europe in medieval times. They are a rich source of protein, fiber, vitamins, and minerals such as B vitamins, folates, and Iron. In addition to their nutritional benefits, grey peas which belong to the pulses family can be cultivated in a sustainable way and by having a small carbon footprint they can indirectly reduce greenhouse gas emissions. They can improve soil fertility by their nitrogen-fixing properties and intercropping with cereals like oats, increases farm biodiversity, and creates a more diverse landscape for animals and insects.
The growing awareness and interest in improving the overall health and minimizing the carbon footprint and environmental impact of dietary choices has led to more attention towards the consumption of pulses. The same trend in Sweden regarding healthy eating and more plant-based diets have promoted the consumption of locally grown pulses such as grey peas. However, the consumption of pulses in Sweden is still low, and processing them further into flour and other fractions and utilizing different processing methods can overcome the limitations of pulse consumption. Pulse flour is a versatile ingredient, both in terms of nutritional profile and functional properties, which can be incorporated in the formulation and development of novel food products.
In order to facilitate and promote the utilization of grey pea flour in food formulations, more knowledge regarding their physiochemical and functional properties and the impact of different processing methods is required. Since limited studies have been conducted to investigate different properties of grey pea flours as well as the impact of different treatment methods on these properties, this project focuses on studying the impact of dehulling, germination, and fermentation on the technological properties of grey pea flour. Besides the effect of the abovementioned properties on the protein and the total phenolic content, the changes in the physicochemical properties including water absorption index, water solubility index and color characteristics, and the functional properties such as water and oil absorption capacity, emulsion activity, and stability, least gelation concentration and pasting properties were investigated and compared to each other.
The results suggest that while some of the treatment methods may lead to better properties, some of them may contribute to poorer properties of grey pea flour, making it difficult to draw a firm conclusion regarding the most effective methods. However, depending on the intended properties of the grey pea flour and the required properties in the food system during formulation as well as the cost and the industrial-scale feasibility, suitable treatment methods can be chosen. Treated pulse flours could be used in food applications such as coating batter, dressings, beverages, or bakery goods.

Popular Abstract

Pulses are the edible seeds of plants in the legume family. Legumes are referred to plants with fruits/seeds enclosed in a pod. The consumption of these nutrient-dense seeds which are rich in protein, dietary fiber and are low in fat, can contribute to a lower risk of cardiovascular diseases and type 2 diabetes. The consumption of more pulses in the diet not only provides nutritional benefits but also is considered to be more sustainable. The recent trends and interests for the consumption of healthy food with less environmental impact are inclined toward promoting pulse consumption. However, the consumption of pulses is still facing limitations mainly due to antinutritional factors and the presence of off-flavors. Antinutritional factors such as polyphenols, enzyme inhibitors, and phytates are called antinutrients since the nutritional value of pulses may be compromised due to the presence of these compounds.
Grey pea, belonging to the pulses family, is a forgotten grain seed in the Nordic countries as well as Sweden. New trends suggest that there is an increasing interest among consumers and food companies to use ingredients from domestically grown pulses in Sweden, including grey peas. Thanks to its high protein content, dietary fiber as well as other nutritional benefits using grey peas can also meet the demand for the formulation of more versatile plant-based products. However, in order to be able to incorporate grey pea as an ingredient in the formulation of novel food products a good knowledge of its properties and the possible effect of processing methods on them is required. These processing methods can also help with the improvement of sensory properties as well as reducing or eliminating antinutritional factors.
This project focuses on studying the impact of dehulling, germination, and fermentation on the technological properties of grey pea flour. The studied properties were chosen in a way to give an overview of important properties that are required for the formulation of different food products. These properties are mainly related to the cooking properties, texture, and mouthfeel of the processed grey pea flour. The project was designed in three different stages to compare the flour samples together. First, the effect of dehulling as a common processing method was studied. Secondly, the effect of germination combined with dehulling was studied. In this stage also the effect of germination time was included. Lastly, the effect of fermentation, combined with dehulling was investigated. All of these processes were then compared with each other in terms of their properties as well as protein and total phenolic content.
The obtained results suggest that depending on the final product and its required properties in which the grey pea flour is going to be used in different processing methods might be desirable or undesirable. For instance, while fermentation can improve certain properties such as water absorption capacity it will lead to poor emulsifying properties making it unsuitable for utilization in salad dressings formulations.

• author: Amanipour, Armaghan
• supervisor: Yvonne Granfeldt
• organization: Food Technology and Nutrition (M.Sc.)
• course: KLGM01 20211
• year: 2021
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: grey pea, flour, technological properties, food technology
• language: English
• id: 9054152
• date added to LUP: 2021-06-30 13:46:17
• date last changed: 2021-06-30 13:46:17