Physical and sensory characteristics of pellets elaborated with different levels of corn grits and whey protein concentrate

Abstract

Whey has proteins of high biological value, which has been used as an ingredient in the elaboration of yogurt, milk beverages and as protein concentrates. Food extrusion stands out as one of the most efficient cooking techniques, allowing a number of product types, from soluble flour to convenience products, such as snacks, which have high acceptability by the consumers. Products processed by extrusion, such as those expanded by frying (pellets), have high carbohydrate content, and its enrichment with protein can favor its nutritional aspect. This study aimed to use the whey protein concentrate (WPC) in combination with corn grits in the preparation of pellets. Absolute density, density of expanded pellets, color, crispness index, and pellet sensory acceptance were determined. For the absolute density, contents from 5% to 17% produced denser non-expanded pellets. The higher the WPC content and the temperature of the extruder, the higher the density of the expanded pellets. The crispness index was not altered by the protein content and by the extruder temperature. In the sensory analysis, the preferred samples were the ones with lower WPC levels (5%). We concluded that higher WPC values in the pellets formulation increased their density, but did not alter color and texture, as well as small WPC levels did not affect the acceptance of snacks.Index terms: Extrusion; sensory; texture. RESUMOO soro lácteo possui proteínas de alto valor biológico, e que vem sendo utilizado como ingrediente na elaboração de iogurtes, bebidas lácteas e na forma de concentrados proteicos. A extrusão de alimentos, destaca-se entre as mais eficientes técnicas de cozimento, proporcionando inúmeros tipos de produtos, desde farinhas solúveis a produtos de conveniência como snacks, apresentando alta aceitabilidade pelos consumidores. Produtos processados por extrusão, como os expandidos por fritura (pellets) apresentam teor elevado de carboidratos, e seu enriquecimento com proteína, pode favorecer o aspecto nutricional do mesmo. Neste trabalho, objetivou-se utilizar o concentrado proteico de soro lácteo (WPC) em combinação com o gritz de milho na elaboração de pellets. Foram determinadas a densidade absoluta, densidade dos pellets expandidos, diferença de cor, índice de crocância, além da aceitação sensorial dos pellets. Para a densidade absoluta, teores de 5 a 17% de WPC deixaram os pellets não-expandidos mais densos. Quanto maior foi o teor de WPC e a temperatura do extrusor, maior foi a densidade dos pellets expandidos. O índice de crocância não foi alterado pelo teor de proteína e temperatura do extrusor. Na análise sensorial, as amostras mais preferidas foram as com menores teores de WPC (5%). Concluímos que maiores valores de WPC nas formulações dos pellets aumentaram a densidade dos mesmos, mas não alteraram a cor e a textura, assim como pequenos teores de WPC não alteraram a aceitação dos snacks.

Effect of Coating on Physico-Chemical Characteristics of Puffed Wheat Grains

“…Such additives as basil, moringa, marjoram, thyme, mint, watercress, amaranth, fenugreek and defatted coconut flour have been used in cereal products (Vishwakarma et al, 2022). For the enrichment of cereal product nutritional value, barberry fruits (Bakmohamadpo et al, 2021), sesame seeds (Hashempour-Baltork et al, 2018), whey protein (Fernandes et al, 2016) and pumpkin (Promsakha na Sakon Nakhon et al, 2018) have been included in product recipes. Among many flavourings, vanilla is considered the most popular and frequently used in the food industry.…”

Suitability studies of different milk proteins for supplementation in functional extruded snack

“…Use of dairy proteins in cereal based products, improves the nutrient density of extruded snacks by increasing protein and mineral content (Brncic et al 2011;Pordesimo et al 2009). Attempts have been made to use whey protein concentrates or dried whey for extrusion purpose (Onwulata and Konstance, 2006;Onwulata et al 2010;Fernandes et al 2016;El-Ghany, et al 2013;Chaudhari et al 2020). The type and level of milk protein incorporated into an extrudate affects the water holding capacity, nitrogen solubility index and sorption characteristics of extruded products (Allen et al 2007).…”