Introduction
Oil–bearing crops include those whose fruits (or mesocarps), seeds, and
nuts are worth for the edible or industrial oils to extracted. The Food
and Agriculture Organization of the United Nations (FAO) listed 21 oil
crops, which collectively yield an annual production of world oilseed
for about 100 million tons (Athar and Nasir, 2005). Vegetable oils have
progressively supplanted animal oils as a major source of dietary fat,
leading to oil crop production becoming one of the prevailing forms of
world agriculture. Oil crops contain diverse array that strengthen
nutritional value of human diet, with the oils generated by such crops
being especially good sources of tocopherol and thus promoting the
balanced intake of vitamin E(Athar and Nasir, 2005; Kornsteiner et al.,
2006). Peanuts, most fundamental food crop in the world, where China,
India, and the United States are top three peanuts worldwide
producers(Arya et al., 2016). The peanuts pods ripen approximately 150
days after the seeds planted. With mechanized reaping, the whole peanut
plant, including the seed pods, are removed from the soil before being
dried (sun or hot–air) and then seed shelling(Arya et al., 2016; Nawade
et al., 2018). Peanuts easily lipid oxidize and decompose during storage
and transportation due to their high–fat level (>50%),
and this influence their nutritional, agricultural and edible safety
importance(Chukwumah et al., 2007; Liu et al., 2018; Hu et al., 2019;
Xie et al., 2019). As the world population evolve, edible oil
consumption has been rising steadily. Edible oils supply most dietary
intake of lipids vitally needed for daily essential due to the energy,
essential fatty acids, and fat soluble vitamins they provide, with such
oils being used generally for frying, baking, cooking, and salad
dressing(Hashempour–Baltork et al., 2016; Lee et al., 2019; Konuskan et
al., 2019). The cooking methods used with edible oils differ in terms of
the temperature, duration, and the amount of oil used. Vegetable oils
are important constituents of the daily diet of most people, although
the actual intake of such oils differs considerably depending on the
cooking methods used. The World Health Organization (WHO) has identified
three important factors for determining the nutritional value of oils:
I) the presence of antioxidants; II) the ratio of saturated fatty acids
(SFA), mono–unsaturated fatty acids (MUFA), and poly–unsaturated fatty
acids (PUFA); and III ) the essential fatty acid ratio
(Hashempour–Baltork et al., 2016). Relatedly, the WHO has recommended a
ratio of 1:1.5:1 for SFA:MUFA: PUFA and a ratio of
1:5~10 for α– linolenic acid (omega–3): linoleic acid
(omega–6) in people’s dietary intake. Vegetable oils are high in MUFA
and, as part of a low–cholesterol diet, have been found to lead to
reduced cardiovascular disease (CVD) risk, in addition to potentially
improving serum lipid profiles, decreasing LDL oxidation, and exerting a
cardioprotective effect (Hashempour–Baltork et al., 2016; Chen et al.,
2008). The antioxidant components in vegetable oils is composed of
hydrocarbons, carotenes, tocopherol, phytosterols, and triterpenes, the
minor constituents of various vegetable oils are associated with
medicinal qualities and thus can be useful in preventing or delaying the
onset of chronic diseases and promoting health(Chen et al., 2008;
Alasalvar and Bolling, 2015; Ghosh et al.,2017).
Organic solvent extraction (mostly using petroleum ether, petroleum
benzene, and hexane) and mechanical pressing are two conventionally used
commercial methods in producing vegetable oils. However, the residual
solvent remains of the former process can cause environmental safety
issues and neurological damage, while mechanical pressing provides only
a low yield of oils (Mingyai et al., 2018; Yang et al., 2018). To
increase the extractability of oil, several destructive pretreatments
need to be performed. Cold‐pressed oils are generated with no refining
process and have good flavor, stable quality, and are high in bioactive
components, qualities which have led them to be regarded as excellent
food oils by consumers (Yang et al., 2018). Roasting, grinding, and
pressing have been the key steps in peanut oil processing. Recent
research findings, however, have given mind to the enhancement of
substitute processing techniques for oil production and flavor. Roasting
constitutes a critical processing stage that affect the color,
composition, conversion to bioactive compounds, and organoleptic
qualities of the extracted oils, as well as their oxidative stability
(Chang et al., 2016; Taş and Gökmen, 2017; Różańska et al., 2019).
Research has shown, for example, that roasting increases the oxidative
stability of sesame oil, with no oxidation being observed for 50 days
after roasting (Rostamiet al.,2014).
Insufficient information regarding edible oils has made it increasingly
difficult for consumers to choose oils for purchase. In this study,
peanuts were roasted at different temperatures (120, 140, and 160℃) to
determine how those roasting temperatures affect the chemical properties
related to the quality of the oils generated. We investigated various
quality indices and the oxidative stability of the generated peanut
oils, as these factors have received increasing attention as edible oils
have been increasingly recognized as a necessary source of antioxidant
components in a healthy balanced diet. Relatedly, the obtained data
should be useful for deepening the understanding of the chemical
profile, in addition to providing scientific evidence for enhancing the
human diet qualities. Moreover, this present work may serve as a worth
reference for future complementary studies aimed at evaluating the
beneficial effects of vegetable oils on human health.