Production of the Suppressed-Pungent Capsaicin Microcapsules

20.09.2019

Capsaicin (8-methyl-N-vanillyl-6-nonenamide; C₁₈H₂₇N_O3) is the main active ingredient of hot red pepper and has high bioavailability. Physically odorless capsaicin has a pungent taste and white color and is very stable against external factors such as freezing, cooking and storage. It is has been reported as a strong compound with a stable structure in the literature studies. Capsaicin causes a painful and burning sensation in the tongue due to the Transient Receptor Potential Vanilloid 1 (TRPV1) channels in human tongue. It is reported that capsaicin has antimicrobial, analgesic, antitumor, antioxidant, blood circulation and metabolism accelerating effects. There are also studies indicating that capsaicin affects cancer cells. The daily diet of capsaicin in mice with lung and prostate cancers has been reported to cause apoptosis in cancerous cells. In addition to all these mentioned benefits of capsaicin on human health, studies are indicating that it has some harmful effects depending on excessive consumption and consumer sensitivity. It is stated that excessive consumption of hot pepper may cause irritation in the digestive system and if the consumption is intensified, these irritations may cause larynx, esophagus and stomach cancers and therefore, excessive consumption of capsaicin should be avoided. In our study, capsaicin was encapsulated by spray cooling method and turned into a product that creates the sensation of burning in the mouth and stomach at a minimum level and does not cause irritation during consumption but can also benefit from all it is benefits. The spray cooling method is an encapsulation technology in which hydrophobic materials such as phospholipids, hydrogenated oils, waxes, fatty acids, polyethylene glycol and mixtures of these materials are used as a coating material. The spray cooling method has been used for many years as an alternative microencapsulation technique in the production of pharmaceutical capsules, in the encapsulation of active materials and volatile components that are sensitive to external agents, particularly water. In the study, firstly, the type of stabilizer and protein suitable for the preparation of capsaicin emulsion was selected. For this purpose, 25 different emulsions were prepared by using whey protein isolate, gelatin, Nacaseinate, soy lecithin, polysorbate 20 and polyglycerol polycrinolate. Capsaicin (≤67%) was used as a core material. Emulsions formed with different proteins and stabilizers were converted to powder form under constant spray cooling conditions and microencapsulation efficiencies were investigated. Considering the results of emulsion stability and microencapsulation efficiency, whey protein isolate as protein and soy lecithin as stabilizer were determined as the most suitable coating materials. In the second stage, the effects of the homogenization rate (10000-20000rpm), the rate of sunflower seed oil in the palm oil (0.5-1.5%), inlet temperature (10-20°C) and the rate of capsaicin in the emulsion (0.1-0.5%) were investigated in the production of suppressed pungent capsaicin microparticles by the spray cooling method according to the CCRD (Central Composite Rotatable Design) experimental design. In this way, 30 different production conditions prepared in the CCRD trial design were tested. Physicochemical analyzes and in vitro gastrointestinal system release analyzes were performed on the powder samples obtained by spray cooling. The optimum production conditions which minimizes the release of capsaicin from microcapsules in the mouth and stomach and maximizes the microencapsulation efficiency, were calculated by using the Design Expert package program. In the third stage of the study, capsaicin microcapsules produced under optimum conditions were packaged in an aluminum coated polyethylene packaging material and stored at 4°C and 25°C for 60 days. The physical and chemical properties of capsaicin microcapsules were investigated every 15 days during the storage. In the last stage, capsaicin microcapsules produced under the optimum process conditions, were added to the model foods. In this context, milk, buttermilk, shalgam juice, salad dressing, plain cake, bread and mayonnaise were chosen as daily consumed foods. Model foods supplemented with capsaicin microcapsules were stored under refrigerator conditions (4°C) for 7 days. During storage, taste and the intensity of the pungency were determined by sensory panels. In all samples, capsaicin release rates in the mouth, stomach and intestines were also analyzed in the static gastrointestinal model system. As a result of sensory panel, buttermilk, shalgam juice, salad dressing, bread and mayonnaise samples added with capsaicin microcapsules, produced by spray cooling, had the highest acceptability scores. In addition, it was observed that capsaicin microcapsules remained stable for 7 days storage in all model foods and the release rate was quite low. The pungency of the capsaicin, microencapsulated by spray cooling, was suppressed by 90-98%. The capsaicin microcapsules, obtained by spray cooling, would contribute to the production of alternative food products such as salad dressings, ketchup, mayonnaise, ice cream, yogurt and cheese for the people who cannot consume hot red pepper and its products due to its pungent effect. Microencapsulated capsaicin also prevents irritation by releasing to a minimum level in the mouth and stomach. It is also predicted that the microencapsulated capsaicin can potentially be used in dietary food products to reduce the prevalence of obesity. Acknowledgement Authors thank to the TUBITAK for the project support (TOVAG Project No:116O499).