Determination of Maximum Oil Yield, Quality Indicators and Absorbance Spectra of Hulled Sunflower Seeds Oil Extraction under Axial Loading

Abstract

The present study aims to estimate the maximum oil yield of hulled sunflower seed samples in a uniaxial process under a load of 40 kN and speed of 4 mm/min. The oil samples were assessed for their quality parameters and spectra curves within the wavelength range of 325–600 nm. The results show that heating temperatures in the range of 40 °C to 80 °C increased the oil output; however, a maximum oil yield of 48.869 ± 6.023% with a minimum energy of 533.709 ± 65.644 J at the fifth repeated pressing was obtained from the unheated sample compared to the heated samples. The peroxide values ranged from 6.898 ± 0.144 to 7.290 ± 0.507 meq O2/kg, acid values from 1.043 ± 0.166 to 1.998 ± 0.276 mg KOH/g oil and free fatty acid values from 0.521 ± 0.083 to 0.999 ± 0.138 mg KOH/g oil, which were within the recommended quality threshold. There were significant spectral differences among the oil samples. A single absorbance peak was observed at 350 nm for all oil samples, indicating low levels of pigment molecules in the oil. The study revealed the need for repeated pressings to recover the considerable residual oil remaining in the seedcake after the first pressing.

Assessment of Quality and Efficiency of Cold-Pressed Oil from Selected Oilseeds

“…This implies that the determined quality parameters varied with oilseed type apart from IV which was significantly homogeneous (p-value < 0.05). In general, the peroxide value (PV) measures the extent to which rancidity reactions have occurred during storage, which is used as an indication of the quality and stability of fats and oils [5,96,97]. Acid value (AV) is a measure of the degree of decomposition of the oil via the action of lipases or other causes, which is accelerated by light and heat [5,98].…”

“…In general, the peroxide value (PV) measures the extent to which rancidity reactions have occurred during storage, which is used as an indication of the quality and stability of fats and oils [5,96,97]. Acid value (AV) is a measure of the degree of decomposition of the oil via the action of lipases or other causes, which is accelerated by light and heat [5,98]. The iodine value (IV) measures the degree of unsaturation in a fat or vegetable oil, which determines the stability of the oxidation of oils.…”

“…In the literature, several of our published studies have been primarily focused on the mechanical and relaxation behaviours of bulk oilseeds under the uniaxial compression process [1][2][3][4][5][6][7][8][9]. In these studies, the effects of processing conditions such as heating temperatures, freezing temperatures, moisture content, pressure, compression speed and diameter of pressing vessels on force-deformation curves, hardness, energy demand, volume energy, oil-point pressure and oil yield were reported.…”

Fluidization‐bed drying and microwave radiation effects on drying rate, fatty acid, protein, and germination of flaxseed

“…Table 5 showed that the fatty acid contents of the oils obtained after drying in a fluidized bed changed slightly ( p > 0.05) with the increase in temperature. These values can be judged appreciably by comparing them to the yields of many oilseeds, such as chia (36.57%–37.2% of oils) (Guiotto et al, 2013) and sunflower seeds (48.869%) (Kabutey et al, 2022). The values in Table 5 also indicated that the extracted oil consisted mainly of linolenic, linoleic, and oleic acids.…”

Hogweed Seed Oil: Physico–Chemical Characterization, LC-MS Profile, and Neuroprotective Activity of Heracleum dissectum Nanosuspension

“…The peroxide value of HSO is 6.28 mEq. peroxide/kg, which is considerably below that of carrot seed oil (16.0 mEq./kg) [ 61 ], higher than that of jatropha seed oil (0.8–1.9 mEq./kg) [ 65 ], and similar to that of sunflower seed oil (6.8–7.2 mEq./kg) [ 66 ]. The acid value of HSO is 0.52 mg KOH/g, and the saponification value is 173.82 mg KOH/g, which is similar to those of pumpkin seed oil (0.57–0.64 mg KOH/g; 189–190 mg KOH/g) [ 63 ].…”