Effect of drying technique on physiochemical and nutritional properties of Eleusine coracana () porridge powder

Eleusine coracana (Finger millet, ragi) is one of the cereals which can cultivate in higher altitudes. This study analysed the effects of various drying techniques such as spray, tray and freeze drying on the retention of micronutrients and structural changes in ragi. Minerals, such as iron and calcium were determined using atomic absorption spectroscopy (AAS) and water-soluble vitamins, such as vitamin B1, B2 and B3 were determined by high-performance liquid chromatography (HPLC). The micronutrient content of freeze-dried ragi powder was observed to be 349.6 ± 0.6 mg/100 g of calcium, 0.550 ± 0.1 mg/100 g of iron, 0.421 ± 0.01 mg/100 g of vitamin B1, 0.193 ± 0.05 mg/100 g of vitamin B1 and 1.103 ± 0.05 mg/100 g of vitamin B3. Along with micronutrients analyses, proximate and various important physiochemical properties were also analysed. Structure analysis of dried ragi using scanning electron microscopy (SEM) indicated that both tray and spray dried ragi show variations in their structure when compared to freeze-dried porridge powder. Crystallisation of starch during drying was determined using Fourier transform infrared (FTIR) spectroscopy. Selected physiochemical properties were also analysed for all dried samples. The results of this study showed that freeze-drying to be the best technique to preserve nutrients over spray and tray drying methods.

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Formulation of fortified instant weaning food from Musa paradisiaca (banana) and Eleusine coracana

Weaning food is a soft, easily digestible type of food other than breast milk for infants aged 6 to 24 months. The present study was conducted to develop cereal-fruit-based complementary foods for infants and evaluate the nutritional quality of such types of foods. Few researchers have focused on formulating weaning foods from locally available, nutritious, and rich ingredients without nutrient loss to reduce malnutrition and infant morbidity rates. In this study, the formulated infant food was prepared from Musa paradisiaca (Nendran banana) and Eleusine coracana (ragi). Formulated weaning food was analyzed using various standard methods, demonstrating that it could provide adequate nutrients to growing infants for their proper growth and development. The shelf life of the weaning food was also studied for a period of 3 months at ambient conditions in two different packaging materials: aluminum and plastic (low-density polyethylene or LDPE), with the aluminum foil pouch exhibiting the best shelf life. This ready-to-serve food, which is formulated and fortified with natural ingredients containing essential macronutrients and micronutrients, could be regarded as highly effective supplementary food for infants. Furthermore, this development has the potential to introduce an affordable weaning product specifically targeted at low socioeconomic groups.

Effect of different drying techniques on the nutrient and physiochemical properties of Musa paradisiaca (ripe Nendran banana) powder

Musa paradisiaca (ripe Nendran) is the staple food of south India, especially Kerala. The present study analyzed the effect of different drying techniques, namely, freeze, spray and tray drying on the retention of nutrients especially micronutrients. Mineral content was determined by using Atomic absorption spectroscopy and Vitamin content was determined through High-performance liquid chromatography. This study aimed to analyze the availability of minerals and water-soluble vitamins in dried ripe banana powder. The micronutrient content of freeze-dried banana powder was observed to be with 486.92 ± 0.12 mg/100 g of potassium, 0.60 ± 0.005 mg/100 g of calcium, 3.10 ± 0.10 mg/100 g of sodium, 3.82 ± 0.02 mg/100 g of iron, 6.28 ± 0.04 mg/100 g of vitamin C and 0.606 ± 0.005 mg/100 g of vitamin B6. Along with micronutrient analysis, proximate, and various important physiochemical properties were also analyzed. The results showed that freeze-drying was the best technique to preserve nutrients present in ripe banana. Structure analysis of dried banana was done using scanning electron microscopy indicated that remarkable changes has occurred in both tray and spray dried banana when comparing to freeze dried banana. Data was analyzed by one-way ANOVA, found significantly differ at p < 0.05 with respect to drying methods.

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