Valorization of the Olive Oil Production Residue: Healthy Ingredient for Developing High Value-Added Spread

Abstract

This study focused on the development of a new olive-based product enriched with proteins, antioxidant compounds and functional properties, aiming at valorization of the olive residue from the typical olive oil extraction process. Olive oil was extracted using a patented cold pressing machine, resulting in a valuable source of bioactive compounds in the form of olive residue (pulp ~70%, pit- and skin-free). Conventional (solid: water ratio 1:4, 25 °C, 2 h) and HP-assisted (200 MPa, solid:water ratio 1/4, 10 min) de-bittering processes were carried out in order to remove oleuropein content (up to 50%) from olive residue, thus decreasing its bitter taste. The olive spread was prepared with olive residue (50%) and honey (25%), enriched with proteins (24.5%) from nuts. Quality parameters, nutritional attributes, microbiological analysis, phenolic compounds and oxidative stability as well as sensory evaluation of the olive spread were conducted during storage. Its shelf-life was estimated (prediction through accelerated tests) as 9.5 months when stored at 4 °C. The organoleptic evaluation showed that the proposed olive spread had a texture similar to peanut butter and could potentially be consumed as a health-promoting spread due to its high content of proteins (~10 g/100 g), crude fibers (>6 g/100 g) and essential fatty acids.

Compostos bioativos presentes no azeite de oliva e seus subprodutos: revisão bibliográfica

“…Corroborando, Andreou, et al, (2021) desenvolveram um produto a base de oliva em que o azeite foi extraído por prensagem a frio e através de processos convencionais removeram certo teor de oleuropeína, diminuindo seu sabor amargo, embora nutricionalmente seja conveniente preservá-lo. A preparação consistiu de 50% de resíduo de oliva enriquecido com 25% de mel e 25% de proteína de nozes.…”

Incorporation of Acid Whey Yogurt By-Product in Novel Sauces Formulation: Quality and Shelf-Life Evaluation

“…Lipid oxidation in food emulsions is considered one of the major indices for their deterioration, producing undesirable components with off-flavors (rancidity) and potentially toxic reaction products, leading to rejection by the consumers [45]. PV limit has been set as 30 meqO 2 /kg, indicating the initial stage of fat oxidation in foods [46]. The rate of lipid oxidation is influenced by many factors, such as the size and concentration of fat droplets, pH value and ingredient interactions of surrounding aqueous media [34].…”

The Effects of Oil Content on the Structural and Textural Properties of Cottonseed Butter/Spread Products

“…These plant-based butter/spread products have been reported from at least 14 plant sources (i.e., almond, canarium, cashew, cottonseed, flaxseed, hazelnut, macadamia, melon seed, peanut, pistachio, pumpkin seed, sesame, soybean, and sunflower seed) [28,[30][31][32][33][34][35]. Recently, olive residue from the typical olive oil extraction process has been tested as a new olive-based spread product enriched with proteins, antioxidant compounds, and functional properties [36]. With strict definitions, the terms "butter" and "spread" have slightly different meanings in terms of the percentage of the main ingredients.…”