Physico-chemical and functionality of air and spray dried egg powder: implications to improving diets

Abstract

Weak market linkages, unavailability of cold-storage, and the significant loss of eggs due to breakage and low shelf-life contribute to the unaffordability and the low consumption of eggs in low-income countries like Ethiopia. The effect of spray-and oven-drying of eggs from local (Ethiopian) and exotic (imported) chicken breeds on physical, techno-functional, and nutritional composition of egg-powders were evaluated. Exotic (n = 150) and local (n = 140) eggs were spray/oven dried. The yield, bulk-density, flowability, and the foaming-, emulsification-, and water/oil absorption-capacity of the egg powders were assessed. The concentrations in energy, protein, fat, ash, and minerals were determined. The egg-powders' contribution to nutrient requirements for a child and their potential use as an alternative protein source in ready to use therapeutic foods (RUTF) were estimated. The low moisture (<5%) and water activity (aw~0.4-0.5) of the egg-powders implied unfavorable conditions for microbial growth. Local eggs had higher energy and fat content, whereas protein was higher in the exotic eggs (P <.05). About 12.5 g of egg powder (one egg) can fulfill >75%, 30%, and 40% of fat, energy, and calcium requirements for children 6-23 months of age, respectively. Only 6 g and 4 g of egg-powder are needed to fulfill protein and choline requirements, respectively. Considering the quality/quantity of proteins, egg powders can be alternative protein sources in RUTFs. The drying of local and exotic eggs with oven-and spray-drying yielded egg powders with acceptable techno-functional properties, but future studies should elucidate differences observed by egg type and drying; and investigate the shelf-life. Drying eggs can be a viable food systems' intervention that can improve the safety and quality of diets in low-income countries like Ethiopia.

Oxysterols in stored powders as potential health hazards

“…The results show that the fat content of powder milk, egg powder and milk–egg powder ranged from 26 to 42 (g 100 g −1 ) and the water content was less than 5%. According to Abreha et al 22 , the low moisture (< 5%) and water activity (a w ~ 0.4–0.5) of egg powders make unfavourable conditions for microbial growth. The fat content of powder milk (26.50 g 100 g −1 ) corresponds to the values obtained by Pugliese et al 23 and the protein content of 27.55 (g100 g −1 ) corresponds to the values obtained by Magan et al 24 .…”

“…Acidity influences the type of oxysterols formed at pH between 5.5 and 3.0, the β-isomer and is more acid labile than the α-isomer, preferentially converting into a triol by hydrolysis 25 . Abreha et al 22 showed in their study that egg powders have a low water activity of 0.4 and acidity between 7.5 and 8.5 pH.…”

Diyetlerde yumurta tozu uygulaması ve yavru gökkuşağı alabalıklarının serum parametreleri üzerine etkileri

“…The basal composition of the experimental diets was based on the National Research Council specifications (NRC, 1993) [13]. The dry matter (105 °C, overnight), ash (650 °C, 6 h), crude protein (nitrogen × 6.25), ether extract, and crude fiber contents of the diets and egg powder (Table 2) were determined according to the AOAC methods [14,15,16,17]. The fish were fed thrice daily throughout the study with a daily feed allowance of 3% of their body weight per day.…”

Comparative Study on Major and Trace Mineral Content of Edible and Eggshell Powders from Ethiopian Local and Exotic Breed Chicken Eggs

“…Oven drying: Oven drying of the edible egg and eggshell was carried out according to (Abreha et al, 2021) in a ventilated oven at 44 °C in place of 6 h. (DHG-9123A Michel, England). The dried whole egg and eggshell were permitted to cool; the flakes were bundled, pulverized using a coffee grinder (FW 100, China), and put through a sieve to card over and done with a 60 mm mesh.…”

“…In Ethiopia context, eggs are recognized by nonprofessional consumers in the class of; 'i) the smaller eggs with deep-yellow colored yolk known as Habesha (local) egg, and; ii) the larger eggs with lighter yellow yolk known as Ferengi eggs and obtained from imported breeds (exotic) egg' (Abreha et al, 2021). Despite this differentiation and consumer preference for the local breed egg, petite information exists about the difference in the nutritional and techno-functional composition of these two egg types, and how they are impacted by drying techniques and breed type variation.…”