Effect of Canning Variables on Minerals Content of Bruchid Resistant, Maz-Type Common Bean Lines

Abstract

Dried beans are rich in proteins and good in important micronutrients like potassium, magnesium, folate, iron and zinc. Canning is a conventional food preserving method in which beans and other products are sterilized by heat after placed in hermetically sealed containers. Screening of bean lines for micronutrient retention during canning is an important input for food industry, beans researcher and other end users. The objectives of this study was to evaluate minerals retention of canned maz-lines common beans. A total of 3 Maz-lines of common beans were evaluated under 9 different canning treatments. Accordingly, mineral contents of maz-type canned common beans were evaluated using atomic absorption spectrophotometer. The result showed maz-type common bean lines and canning variables significantly affects minerals content. The highest calcium (68.79mg/100g) and zinc (2.68mg/100g) were exhibited in Maz-200 common bean lines. Canning variables caused an increment of sodium and calcium contents. However, potassium and zinc contents of canned beans decreased as result of varied canning variables. Good retention of potassium was demonstrated in samples soaked at ambient temperature for 30minutes before blanched at 88°C for 30 minutes. Similarly, good retention of zinc was recorded for sample soaked at room temperature for 40 minutes followed blanched at 75°C for 40 minutes.