Potato Nutritional and Sensory Quality

Published on 28 October 2010 in Food, health and wellbeing

Introduction

In the UK, the potato supply chain progresses in value from £450m at the farm gate to a retail value of £3.6bn and so is of major economic importance. In Scotland the seed potato industry is particularly important and there is a strong demand for new improved cultivars that can compete internationally.

In recent years there has been a growing realisation that traits important to consumers need to be addressed to maintain repeat purchase. There is also a public perception that the flavour of modern cultivars is lacking. To address these issues research is ongoing, aimed at producing potatoes and convenience potato products with improved aroma, taste, texture and nutritional value as well as addressing health concerns over carbohydrate-based diets.

Potato flavour is due to both the flavour volatiles released on cooking and the soluble taste compounds associated with the potato matrix. In order to assess different flavours, trained taste panel assessments are required in combination with analysis of different types of potato. Consistency in the texture of cooked potato products is also important for both domestic consumption and processing.

Particularly in Scotland, potatoes are an important food staple with wide consumer appeal. There is an enormous potential to enhance overall nutritional status by ensuring that the consumed product is optimised for levels of nutrients perceived as being beneficial to health, such as vitamins, minerals and carotenoids. On the other hand there is a drive to reduce acrylamide production in fried and roasted products, as this may have a negative impact on health.

Key Points

• The potato industry is very important to the UK and Scottish economies.
• Flavour, texture and nutritional quality of potatoes are important to consumers.
• In order to breed successful new types of potato there are new opportunities arising from scientific breakthroughs in the fields of genetics and molecular biology.

 

 

Figure 1: Yellow-fleshed Solanum phureja tubers contain higher levels of carotenoids than those found in Solanum tuberosum types.

Research Undertaken

Within the Commonwealth Potato Collection, curated at SCRI, are potato types which have very diverse flavours, textures and nutritional qualities. An approach to understanding the reasons for differences in these qualities is to analyse the chemical constituents of the different types and correlate the different constituents with the characteristics of the potatoes. For example, analysis of the flavour volatiles released during boiling of potatoes demonstrated that the better tasting potatoes released much higher levels of certain volatiles. The matrix of the more highly flavoured potato also contains higher levels of taste compounds thought to be associated with better flavour.

Similarly, a key factor involved in the texture of cooked potato is the chemical nature of the cell wall. Screening of potato collections has also enabled us to identify types that produce only very low levels of acrylamide in crisps. Finally we are starting to understand why some potato types have yellow flesh containing carotenoids, whereas the white-fleshed types lack these potentially beneficial compounds.

Using new genomic tools and benefitting from the recently completed potato genome project, we can start to discover new genes that control the nutritional and sensory traits. Several potential flavour and texture genes are currently being tested.

We are in the process of developing gene markers that can help to accelerate traditional potato breeding and incorporate better nutritional and sensory quality into new Scottish potato types.

Figure 2: Quantitative analysis of potato tuber textural properties.

Policy Implications

• The nutritional qualities of our staple foods such as potatoes, are important factors in the health of the population.
• Agriculture is an important component of the Scottish economy and plays an important part in maintaining rural communities.
• Novel potato cultivars also underpin the potato processing industry, important for wealth creation.

Author

Mark Taylor, SCRI Mark.Taylor@scri.ac.uk

Topics

Food, health and wellbeing

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