PHYSICAL AND PHYSIOLOGICAL CHARACTERISTICS OF POTATO TUBERS RELATED TO STORAGE CONDITIONS

Document Type : Original Article

Authors

1 Prof. of Food Eng., Fac. of Ag., Alexandria Univ. Egypt.

2 Researcher, Ag. Eng. Res. Inst., Ag. Res. Center, Dokki, Giza, Egypt.

Abstract

The aim of this investigation is to study the effect of traditional and cold storage condition on physiological and physical characteristics of Lady Rosetta potato tuber variety, as one of the most important commodity for chips industrials and for exporting, but it is very sensitive for handling and storage. Half ton of fresh tubers of each of two soils cultivar (Sandy and Black soil) were cleaned and the deteriorate tubers were discarded. The tubers were graded into three sizes based on its mass. Potato tubers were cured, then the potatoes of each cultivar were divided into two samples each of 250 kg for long term storage (200 days) under two different conditions, Nawalla (aerated natural traditional condition), and under cooling condition (8C̊ and relative humidity of 85 %).The results data of fresh and stored potatoes of different storage treatments including physiological and physical characteristics demonstrated graphically and statistical analysis conducted. The physiological measurements are moisture content, sugar content and respiration rate. The physical characteristics measurements are including dimensions, surface area, volume, spherecity, mass, particle and bulk density. Analysis of the results obtained showed that there are linear multiple regression relationships between each of mass loss %, shrinkage of tuber dimensions %, shrinkage of volumes %, particle and bulk density at each of storage condition, storage periods, tubers mass and static load stress for each of sandy and black soil cultivars. Respiration rate (mg CO2/kg.h) of fresh tubers was directly proportion with tuber specific surface area and inversely proportion with tubers mass for all cultivars. Sugar content (Brix) positively affected by each of type of soil, storage temperature, static load stress, storage time and tuber mass.

Main Subjects


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