Twenty potato varieties were grown under 5 contrasting environments in Peru and have been tested by 40 volunteer panelists, who evaluated the taste and the texture of boiled potato tubers of 4 clones per day for a week. The panelists belong to different areas of CIP, such as administration, laboratories, and experimental field stations.
“For our first experiment, we used 15 clones of late-blight-resistant and heat-tolerant potato clones planted under five contrasting environmental conditions: in San Ramón, La Molina in summer and in winter, Majes (Arequipa), and Huancayo,” explained Gabriela Burgos, Associate Researcher at CIP’s Disciplinary Center of Excellence “Genetics, Genomics and Crop Improvement”, and Head of the Quality and Nutrition Lab at CIP in Lima/Peru. “San Ramón is an environment with conditions of heat stress, while Majes has conditions of drought stress . The idea of the evaluation is to discover whether the environment conditions such as soil and climate affects the taste of the potato,” she added.
“It is the first time that this kind of study has been performed at CIP,” continued Gabriela Burgos. “We have limited financial resources, but we hope that in the near future more attention will be given by donors to sensorial evaluation of all potato breeding material developed at CIP., That is especially important under worldwide appearing climate change conditions affecting agriculture systems with increased different types of abiotic stresses such as heat and drought but also irregular rainfall. Protection mechanisms of plants include accumulation of secondary metabolites that could affect the taste and texture, of potato tubers and even can be toxic for human consumption when reaching an unsafe level” she explained.
“We have assured that at least 75 % of the panelists are the same participants for all 5 growing environments, to ensure that the results are comparable and not biased by personal likes,” explained Edith Cayhualla, research assistant in CIP’s Quality and Nutrition Laboratory in Lima/Peru. “The results of this study will let us know under which environmental conditions the tested potato clones varieties are on risk to develop a bitter/astringent taste, change the flesh color or change the texture/mouthfeeling that makes them less acceptable for end users,” Edith said.
The results of the sensorial evaluation will also be linked with the concentration of glycoalkaloids and other secondary metabolites to determine whether the observed bitterness is due to an increase in these components. “Medium -term we hope to develop a fast screening technique for detecting unsafe levels of secondary metabolites that produce a non-acceptable taste in advanced breeding clones before they become a new variety” explained Dr. Thomas zum Felde, who leads the project .
For the panelists, who have been working for many years at CIP, this sensorial evaluation has been a new – but not wholly strange – experience. “It’s the first time I have participated in this kind of evaluation,” said Cecilia Ferreyra, the librarian. “It seemed easy, but I think that’s probably because I am so used to the topic of quality, color, and other characteristics that the potato should have for me. I think that if they asked me to do the same taste testing for a different crop, for example sweet potato, I wouldn’t be able to answer very precisely, and even less so if it were another root or tuber crop such as oca, mashua, or arracacha,” she added.
However, to be a good panelist you need to be able to recognize or detect a bad or different taste. “Not all the participants have that skill, but we have already identified those who do, and we are very pleased that they will be participating until the experiment comes to an end,” Edith Cayhualla.