Valorization of roasted longan stone in production of functional biscuits with high antioxidant activity and dietary fiber

Abstract

Being waste products of the food industry, longan stones can be a promising functional food ingredient owing to their high fiber content, nutrients and antioxidative properties. Biscuits were enriched with roasted and unroasted longan stone powder. The longan stones were roasted at 170 °C for 5, 15, and 25 min by using a fluidized bed roaster. Longan stone powders were incorporated in wheat flours at different concentrations. Biscuits were obtained with higher fiber content (5.72 ± 0.03%) and lower fat content (12.50 ± 0.02%) compared to the control biscuits. Antioxidant activity (51.18 ± 0.02% inhibition) and total phenolic contents (394.61 ± 0.63 mg GAE/100 g) of the biscuits increased significantly as the roasting degree of added longan stone powder increased (p≤0.05). Biscuits enriched with longan stone powder roasted during 15 minutes took higher sensory scores than control biscuits and biscuits enriched with unroasted longan stone powder. The roasting process increased the acceptability of addition longan stone powder.

Organoleptic, antioxidant activity and microbial aspects of functional biscuit formulated with date fruit fibers grown in Qassim Region

“…Color of biscuit surface samples formulated with different DFs levels were measured by Hunter Lab Color QUEST II Minolta CR-400 (Konica Minolta Inc., Osaka, Japan) according to the method described in Francis (1983) that has been modified according to recent published similar samples (Bölek, 2022). The measurements were expressed in L*, a*, and b* values which represents light-dark spectrum with a range from 0 (black) to 100 (white), the green-red spectrum with a range from -60 (green) to +60 (red), and the blue-yellow spectrum with a range from -60 (blue) to +60 (yellow) dimensions, respectively.…”

“…A blank sample consisting of water and reagents was used as a reference. Gallic acid was applied as a standard, and the results were expressed as mg gallic acid equivalent (Bölek, 2022). The ability of the extracts to scavenge DPPH free radicals was determined by the method described by Valko et al (2007).…”

“…Form such point of view high levels of dietary fibers and antioxidant activity are increased worldwide among all age groups as functional foods with health oriented bakery products. Indeed, such components contributed to improve immune system functions, digestive, lowering cholesterol levels coroner health diseases and type-2 diabete so using dates fruit fibers (DFs) as many plant dietary fibers may have many beneficial properties (Bölek, 2022). Therefore, consuming such DFs could be used as protective factor against degenerative disorders especially obesity with its consequences (diabetes mellitus, cardiovascular diseases, constipation, and colon cancer).…”

“…So it could be concluded that the new supplemented products; biscuits with DFs could be the best after 5% and 10% DFs additions. Indeed, pervious enriched biscuits with different dietary powders such as dried pomegranate peel powder and olive stone powder changed the hardness levels and factorability due to the water content decreased (Bölek, 2022)…”

“…Sensory analysis of new formulated biscuits is important as any food sensory characteristic can affect significantly the choice of consumers in order to be recommended for the marketplace due to its nutritional values and its overall acceptability (Bolek & Ozdemir, 2017;Bölek, 2022). So the acceptable DFs added amounts should be identified; may alter the consumers' attitude to products with the best sensory evaluation.…”