Optimisation of red pepper seed oil extraction using supercritical CO2 and analysis of the composition by reversed-phase HPLC-FLD-MS/MS

Supercritical fluids and fluid mixtures to obtain high-value compounds from Capsicum peppers

Peppers of the Capsicum genus have a rich nutritional composition and are widely consumed worldwide. Thus, they find numerous applications in the food, pharmaceutical and cosmetic industries. One commercial application is oleoresin production, a nonpolar fraction rich in bioactive compounds, including capsaicinoids and carotenoids. Among the technologies for pepper processing, special attention is given to supercritical fluid technologies, such as supercritical fluid extraction (SFE) with pure solvents and CO2 plus modifiers, and SFE assisted by ultrasound. Supercritical fluid-based processes present advantages over the classical extraction techniques like using less solvents, short extraction times, specificity and scalability. In this review, we present a brief overview of the nutritional aspects of peppers, followed by studies that apply supercritical fluid technologies to produce extracts and concentrate bioactives, besides oleoresin encapsulation. Furthermore, we present related phase equilibrium, cost estimation, and the gaps and needs for the full use of peppers from a sustainable perspective.

Pilot-Scale Optimization of Supercritical CO2 Extraction of Dry Paprika Capsicum annuum: Influence of Operational Conditions and Storage on Extract Composition

Supercritical carbon dioxide extraction was used to extract carotenoids from dry paprika Capsicum annuum. Studies regarding the effect of process parameters, including pressure (25–45 MPa), temperature (40–60 °C), and time (10–110 min), were carried out using response surface methodology. It was found that under optimal conditions (pressure of 45 MPa, temperature of 50 °C, and time of 74 min), the extract yield was 10.05%, and the total content of carotenoids in the extract was 4.21%, in good agreement with the predicted values (10.24% and 4.24%, respectively). Composition analysis showed that paprika extract mainly consisted of linoleic acid. There was no significant difference between the fatty acid content of the extracts obtained by SC-CO₂ extraction and n-hexane Soxhlet extraction. For functional purposes, the effect of storage conditions and time on the quality of paprika extract was also specified.

Quality of Pepper Seed By-Products: A Review

Peppers are grown all around the world, usually for fresh consumption, as well as for the industrial production of different products. Pepper (Capsicum annuum L.) seeds are mostly considered a by-product. Recent investigations have shown that pepper seeds have the potential to be a valuable source of edible oil and fiber-rich flour and protein after processing. Pepper seed oil is a high-quality edible oil according to quality analysis (nutritional, chemical, sensory and antioxidant characteristics) and is suitable as an ingredient for use in the food and nonfood industries (pharmaceutical, chemical, cosmetic industries). The literature review presented in this paper revealed the high quality of two pepper seed by-products (pepper seed oil and pepper seed flour (Capsicum annuum L.)), which could guide the food industry toward new product development based on the circular bioeconomy.

Podravka and Slavonka Varieties of Pepper Seeds (Capsicum annuum L.) as a New Source of Highly Nutritional Edible Oil

The aim of this study was to evaluate Croatian pepper seed varieties (Podravka and Slavonka) as a new source of added value ingredients. Pepper seed is mostly considered a by-product. For the first time, the pepper (Capsicum annuum L.) seeds of the Slavonka and Podravka varieties were examined as the source material for oil production by the two methods of extraction: cold pressing (CP) and supercritical CO2 extraction (SC-CO2). Further, fatty acid profile, tocopherols, and sensory analysis of the oils were examined, as well as the chemical characteristics and antioxidant potential of seed flour. The antioxidant potential of pepper seed flour was different between varieties (Podravka 107 antioxidant unit (AU); Slavonka 70 antioxidant unit (AU)). The Podravka variety pepper seed oil has shown higher γ-tocopherol content (CP 80.1 mg/100 g; SC-CO2 extraction 65.3 mg/100 g) than the Slavonka variety (CP 65.3 mg/100 g; SC-CO2 extraction 16.0 mg/100 g). According to the obtained results, cold pressing (CP) would be a more favourable method for pepper seed oil extraction, taking into account sensory evaluation and nutritional quality. The pepper seed oil has potential for culinary application with a nutritional quality comparable to vegetable oils of a higher price class.

Hypolipidaemic effect and mechanism of paprika seed oil on Sprague-Dawley rats

BACKGROUND

Details regarding the functional properties of paprika seed oil are relatively scarce. In this study the hypolipidaemic effects and mechanisms of paprika seed oil on Sprague-Dawley rats are explored, which may improve the usage of paprika seed source and provide a theoretical basis of paprika seed oil for the alleviation of hyperlipidaemia.

RESULTS

In capsaicin and paprika seed oil (PSO) groups, total cholesterol (TC) and total triglyceride (TG) in serum and liver lipids of rats were significantly decreased (P < 0.05). The contents of serum HDL cholesterol were increased and the contents of serum LDL cholesterol were decreased (P < 0.05). Real-time PCR analyses revealed that the hepatic mRNA expression of fatty acid synthetase (FAS) is decreased and the expression levels of HSL is increased (P < 0.05). The mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) is decreased and the expression levels of low-density lipoprotein receptor (LDLR) is significantly improved (P < 0.05). The cholesterol 7-hydroxylase (CYP7A1) expression is regulated to control the cholesterol-to-bile acid transformation and cholesterol excretion is promoted. Capsaicin and unsaturated fatty acid PSO can activate and improve the mRNA expression of transient receptor potential vanilloid type-1 (TRPV1) and peroxisome proliferators-activated receptors (PPARα).

CONCLUSION

The hypolipidaemic effects of paprika seed oil (PSO) may be attributed to the inhibition of lipid synthesis via suppressing the expression of HMG-CoAR, CYP7A1 and FAS, meanwhile, promoting the metabolism and excretion of lipids via up-regulating the expression of LDLR, HSL, TRPV1 and PPARα. © 2017 Society of Chemical Industry.

Process optimization and characterization of fragrant oil from red pepper (Capsicum annuum L.) seed extracted by subcritical butane extraction

BACKGROUND

Red pepper seeds account for 450-500 g kg^-1 of the total pepper weight and are often discarded as waste. In this study, process optimization and characterization of fragrant oil from roasted red pepper seed extracted by subcritical butane extraction were carried out.

RESULTS

The optimal conditions of extraction were a temperature of 74.61 °C, a time of 68.65 min and a liquid/solid ratio of 30.24:1. The oil had a refractive index (25 °C) of 1.471, a relative density of 0.900, an acid value of 1.421 mg g^-1 oil, an iodine value of 127.035 g per 100 g, a saponification value of 184.060 mg KOH g^-1 , an unsaponifiable matter content of 12.400 g kg^-1 , a peroxide value of 2.465 meq. O₂ kg^-1 and a viscosity of 52.094 cP. The main fatty acids in the oil were linoleic acid (72.95%) followed by palmitic acid (11.43%) and oleic acid (10.00%). The oil showed desirable thermal and oxidative stability. A total of 19 volatile compounds, mostly aldehydes and alkenes, were identified from the oil.

CONCLUSION

The results indicated that the method is appropriate for the preparation of fragrant red pepper seed oil, and the oil is suitable for used as edible oil. © 2016 Society of Chemical Industry.