Effects of storage temperature and relative humidity on cooking time and moisture uptake of selected common bean (Phaseolus vulgaris L.) varieties grown in Ethiopia

Abstract

Common beans (Phaseolus vulgaris L) are important legumes rich in nutrients. However, the defect to cook or hard-to-cook (HTC) defect is among the challenges of legume crops during storage. Hence, this study aimed to determine the effects of storage temperature and relative humidity (RH) on cooking quality and moisture uptake of the selected recently released common bean varieties. Different storage conditions combinations were used for the analysis: ambient storage at 25°C and 65% RH as control storage; storage conditions of 35°C and 75% RH; and 35°C and 85% RH were explored. Zoasha, Nasir, Awash Weten and control bean varieties show reduced moisture uptake and increment in cooking time. The moisture uptake of Zoasha reduced from 127% immediately measured after harvesting to 79% (45°C/85%RH). Nasir, Awash Weten and the control sample varieties of beans reduced their moisture uptake from 121% to 74%, 124% to 75% and 142% to 90%, respectively. Those results show that accelerated storage conditions had a significant (P ≤ 0.01) effect on the moisture uptake. The initial cooking time of Zoasha, Nasir, Awash Weten and control samples were 101 minutes, 104 minutes, 101 minutes and 89 minutes, respectively. But, at accelerated storage conditions, the cooking time increased significantly (P ≤ 0.01) by 120%, 117%, 95% and 115%, respectively, for Zoasha, Nasir, Awash Weten and control sample varieties. At accelerated storage condition, the control sample should have the lower energy consumption by decreasing the cooking time by 25%, 22% and 20% from Zoasha, Nasir and Awash weten, respectively. The result could give an insight for food processors, breeders and policymakers to consider the hard-to-cook effects for the aforementioned common bean varieties.

Keywords:

• Awash Weten variety
• common bean
• cooking time
• hard-to-cook defect
• moisture uptake
• Zoasha variety
• Nasir variety

Public interest statement

Common beans hard-to-cook (HTC) effect issue is a challenge for food scientists and technologists to control. The postharvest storage conditions, such as temperature and relative humidity, affect the HTC phenomena. The HTC-affected beans demand more cooking energy, which costs a lot. The adverse effects of the storage conditions, such as temperature-RH combinations of ambient storage (25°C and 65% RH) as a control, 35°C and 75% RH storage condition, 35°C and 85% RH storage conditions were affected HTC effect on the bean varieties. As a result, at accelerated storage conditions, the cooking time increased significantly by 88%, 93%, 94% and 63%, respectively, for Zoasha, Nasir, Awash weten and control sample varieties. The result can give insight into the food processors and the scientific community about the HTC effects of the specified common bean varieties.

Acknowledgements

The researchers would like to acknowledge the Ethiopian Institute of Agricultural Research for funding the budget and all Werer Agricultural Research Center staff for suppoWerner any required material for the experiments. Moreover, Haramaya University, Department of Food Science and Postharvest Technology staff members are acknowledged for research facility support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors received no direct funding for this research.

Notes on contributors

Melese Mulu Abay

Melese Mulu Abay is a researcher at the Ethiopian Institute of Agricultural Research, Werer Agricultural Research Center, Ethiopia. His fields of specialization is in Food Science and Technology. His research interest focuses on food processing technology, food product development for children, and food quality and safety.

Getachew Neme Tolesa

Getachew Neme Tolesa is a researcher and lecturer of Food Science and Postharvest Technology at Haramaya University with over 15 years of experience in teaching and research. He specializes in Food Science and Postharvest Technology and mainly works and publishes in the areas of postharvest food preservation, postharvest handling, food value-addition, food science, food processing, food engineering, food value chain, food safety and nutrition intervention developments.