The quality and volatile-profile changes of Longwangmo apricot (Prunus armeniacaL.) kernel oil prepared by different oil-producing processes

Comparison of chemical compositions and aroma characteristics of walnut oil prepared by different roasting processes

Walnut oil is an edible oil with high nutritional value, and the roasting process influences its quality and flavor. This study aimed to investigate the effects of roasting on the fatty acid composition, bioactive compounds (tocopherols, polyphenols, and phytosterols), and antioxidant capacity of walnut oil. Additionally, the aroma compounds and sensory characteristics were evaluated to comprehensively assess the variations in walnut oil after roasting. Roasting resulted in no notable impact on the fatty acid composition of walnut oil but increased the content of tocopherols and polyphenols in walnut oil, increasing its antioxidant capacity. Heavy roasting (160°C/20 min) reduced the phytosterol content in walnut oil by 2.3%. In total, 146 volatile compounds were detected in both cold-pressed and roasted walnut oil using headspace solid-phase microextraction-gas chromatography-mass spectrometry, and 32 key aroma compounds were identified. Aromatic aldehydes, aliphatic aldehydes, and heterocyclic compounds significantly contributed to fragrant walnut oil. Furthermore, the principal component analysis based on quality characteristics and sensory evaluation indicated that moderate roasting (130°C/20 min, 130°C/30 min, and 160°C/10 min) provided walnut oil with a sweet, nutty, and roasted aroma, as well as high levels of linoleic acid, phytosterols, and γ-tocopherol. Although heavy roasting (160°C/15 min and 160°C/20 min) enhanced the antioxidant capacities of walnut oils due to high levels of polyphenols, the oils exhibited an unpleasant burnt aroma. This study showed that roasting promoted the quality and flavor of walnut oil, and moderate conditions endowed walnut oil with a characteristic-rich flavor while maintaining excellent quality.

Apricot kernel characterization, oil extraction, and its utilization: a review

Apricot (Prunus armeniaca L.) kernels, one of the economical stone fruit kernels, are utilized worldwide for edible, cosmetic, and medicinal purposes. Oil from the apricot kernel is valued by the richness of unsaturated fatty acids, the high proportion of oleic acids, phenols, and tocopherol content. Oil yield with quality from apricot kernel varies with region, variety, and adopted method of oil extraction. This review discusses apricot kernel characterization, different conventional and novel methods of oil extraction, their merits and demerits as reported in the literature. Novel technologies such as microwave-assisted oil extraction, ultrasound-assisted oil extraction, enzyme-assisted oil extraction, and supercritical fluid oil extraction have emerged as the most promising extraction methods that allow efficient oil recovery in very environment-friendly ways. Knowledge of the extraction technique aids in giving higher oil recovery with minimal nutritional losses while retaining the original organoleptic properties.

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Comparative Analysis of Flavor, Taste, and Volatile Organic Compounds in Opossum Shrimp Paste during Long-Term Natural Fermentation Using E-Nose, E-Tongue, and HS-SPME-GC-MS

The present study focused on the determination of color, flavor, taste, and volatile organic compounds (VOCs) changes of shrimp paste fermented for 1, 2, 3, and 8 years by E-nose, E-tongue, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). During fermentation, the color of shrimp paste turned dark brown with decreases in L*, a*, and b* values. Inorganic sulfide odor was dominant in all fermented samples. The umami, richness, and aftertaste-B reached a maximum in year 3 of fermentation. A total of 182 volatiles, including long-chain alkanes, esters, aldehydes, olefins, ketones, acids, furans, and pyrazines, were detected. Sixteen VOCs including dimethyl disulfide, methional, trimethyl-pyrazine, (E,E)-2,4-heptadienal, benzeneacetaldehyde were selected as flavor markers. Correlation analysis showed that 94 VOCs were related to saltiness while 40, 17, 21, 22, and 24 VOCs contributed to richness, umami, aftertase-B, sourness, and bitterness, respectively. These novel data may help in optimizing fermentation duration to achieve target flavor indicators in opossum shrimp paste production.

Valorization of by-products from Prunus genus fruit processing: Opportunities and applications

Food processing, especially the juice industry, is an important sector that generate million tons of residues every. Due to the increasing concern about waste generation and the interest in its valorization, the reutilization of by-products generated from the processing of popular fruits of the Prunus genus (rich in high-added value compounds) has gained the spotlight in the food area. This review aims to provide an overview of the high added-value compounds found in the residues of Prunus fruits (peach, nectarine, donut peach, plum, cherry, and apricot) processing and applications in the food science area. Collective (pomace) and individual (kernels, peels, and leaves) residues from Prunus fruits processing contains polyphenols (especially flavonoids and anthocyanins), lipophilic compounds (such as unsaturated fatty acids, carotenes, tocopherols, sterols, and squalene), proteins (bioactive peptides and essential amino acids) that are wasted. Applications are increasingly expanding from the flour from the kernels to encapsulated bioactive compounds, active films, and ingredients with technological relevance for the quality of bread, cookies, ice cream, clean label meat products and extruded foods. Advances to increasing safety has also been reported against anti-nutritional (amygdalin) and toxic compounds (aflatoxin and pesticides) due to advances in emerging processing technologies and strategic use of resources.

Phytonutrients of Bitter Apricot Seeds Modulate Human Lipid Profile and LDL Subfractions in Adults with Elevated Cholesterol Levels

The objective of the present study was to evaluate the effect of short-term consumption of bitter apricot seeds phytonutrients on cardiovascular risk factors with a special focus on LDL cholesterol subfractions using the Lipoprint system. A group of 34 adult volunteers (21 female/13 male) consumed 60 mg kg⁻¹ of body weight of bitter apricot seeds daily for 42 days. Subjects were divided into two groups: one with normal cholesterol levels (NTC) and one with elevated total cholesterol levels (ETC). Blood serum levels of total cholesterol (T-C), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C), and triglycerides (TG) did not change significantly (p > 0.05) in NTC group. However, there were significant decreasing of T-C (p ˂ 0.05) and LDL-C (p < 0.01) in ETC group. The LDL₁, LDL₂, and atherogenic LDL₃₋₇ subfractions progressively decreased after 42 days of apricot seeds consumption in ETC group (p < 0.05). Apricot seeds consumption was associated with a significant increase in the mean LDL particle size especially in ETC group (p ˂ 0.01). The results of the present study support the hypothesis that daily consumption of bitter apricot seeds for 42 days positively modified the lipoprotein profile in the group with elevated total cholesterol.

Fatty acid composition, bioactive phytochemicals, antioxidant properties and oxidative stability of edible fruit seed oil: effect of preharvest and processing factors

Fruit seed is a by-product of fruit processing into juice and other products. Despite being treated as waste, fruit seed contains oil with health benefits comparable or even higher than the conventional seed oil from field crops. In addition to essential fatty acids, the fruit seed oil is a rich source of bioactive compounds such as tocopherols, carotenoids, flavonoids, phenolic acids and phytosterols, which have been implicated in the prevention of chronic and degenerative diseases such as cancer, diabetes and cardiovascular diseases. The emerging potential of fruit seed oil application in food and nutraceuticals has prompted researchers to study the effect of preharvest and processing factors on the seed oil quality with respect to nutritional qualities, antioxidant compounds and properties. Herein, the effect of cultivar, fruit-growing region, seeds pretreatment, seeds drying and seed oil extraction on tocopherols, polyphenols, phytosterols, carotenoids, fatty acids, antioxidant activity and oxidative stability of the fruit seed oil is critically discussed. Understanding the influence of these factors on seed oil bioactive phytochemicals, nutritional qualities and antioxidant properties is critical not only for genetically improving the oilseeds plants with desired characteristics, but also in seed oil processing and value addition. Therefore, preharvest and processing factors are essential considerations when determining the application of fruit seed oil.

Fruit seeds and their oils as promising sources of value-added lipids from agro-industrial byproducts: oil content, lipid composition, lipid analysis, biological activity and potential biotechnological applications

Thousands of tons of fruit seeds are discarded every year worldwide as agro-industrial byproducts. Fruit seeds have a high oil content, are rich in monounsaturated fatty acids (FA) and in n-6 and n-3 polyunsaturated essential FA. Sterols, phospholipids, glycolipids, carotenoids, tocopherols and polyphenols are other seed phytochemicals that make them interesting from a commercial viewpoint. Fruit seeds have high potential as raw material for several industries, but their lipid profile remains poorly studied. Current analytical approaches for the analysis of lipids that are based on high-performance liquid chromatography and high-resolution mass spectrometry allow the separation and analysis of compounds with the accurate identification and structural characterization of molecular species in very small quantities. Even though lipidomic analysis of fruit seeds' lipids is still in its infancy, it will bring a new look over these value-added byproducts. This review covers the following topics: (a) the lipid content of various fruit seed oils; (b) their lipid composition (FA, triacylglycerol, sterol, phospholipid and glycolipid profiles), (c) current and future analytical methodologies for the analysis of lipids in fruit seeds; (d) biological activities of fruit seeds' extracts; and (e) potential biotechnological applications of fruit seed oils for their commercial valorization based on lipids.

Effect of Roasting Temperatures on the Properties of Bitter Apricot (Armeniaca sibirica L.) Kernel Oil

Volatile compounds and quality changes of bitter apricot (Armeniaca sibirica L.) kernel oil (AKO) with different roasting conditions were determined. Bitter apricot kernels were roasted at 120, 130, 140 and 150°C for 15 min. Unroasted bitter apricot kernel oil was used as the control. Quality indicators included color, acid value and peroxide value, fatty acids, total phenols and oxidative stability. Peroxide values of the tested oils were 0.46-0.82 meq/kg, acid values were 0.60-1.40 mg KOH/g, and total phenol contents were 54.1-71.5 μg GAE/g. Oleic acid was the major fatty acid, followed by linoleic, palmitic, stearic and palmitoleic acids. Roasting increased the oxidative stability of bitter AKO. Volatile compounds were tentatively identified and semi-quantified. Among the 53 volatiles identified, benzaldehyde and benzyl alcohol were the major components. These two aroma compounds increased significantly during roasting and contributed sweet and almond flavors. Pyrazines were also prevalent and significantly increased with roasting. Sensory evaluation showed that roasted, nutty, sweet and oily aromas increased as roasting temperature increased.Practical applications: Bitter apricot kernels cannot be consumed directly, thus it is potentially beneficial to find uses for them, especially in China where bitter apricot processing is a significant industry. Roasted bitter AKO with a pleasant aroma could be prepared and might find use as an edible oil. The roasting process gave the bitter AKO a pleasant flavor. This study provided preliminary information on production parameters and potential quality control parameters.