Brazilian Conference on Natural Products
7th Brazilian Conference on Natural Product/ XXXIII RESEM Proceedings

Raw materials with high nutritional value and functional properties should be used in health products development. Cereal bars are complexly formulated food whose combination of ingredients should ensure that they complement each other in taste, texture and physical properties.(1) The association between cereal bars and bioactive substances is a trend in the food sector, resulting in a large profit for food market. Quercetin, for example, is a flavonoid with a high antioxidant capacity. Therefore, there is a growing body of literature that suggests the influence of daily consumption of quercetin in prevention of oxidative stress related diseases, such as cardiovascular disease, diabetes, cancer and inflammatory processes.(2) In this context, this work aimed to study the combination of cereals, plant extracts and quercetin (500 mg/unit) in a cereal bar formulation, which was submitted to the evaluation of the physicochemical (quercetin content and humidity) and microbiological stabilities.
The study was conducted to verify the accelerated stability, when the samples were placed in climatic chambers at a temperature of 40 ± 2ºC and humidity of 75 ± 5% RH, and the long-term stability, with a temperature of 30 ± 2ºC and humidity of 75 ± 5% RH. Samples were analyzed immediately after production (T0) and after three (T3) and six (T6) months of packaging. The quercetin content and humidity measurements were also performed for the quercetin raw material before the bars elaboration.
ANVISA determines(3) a 20% variation of label value to active substance content (80 - 120%; or 400 – 500 mg/unit). The analysis was performed by High Performance Liquid Chromatography (HPLC) with ultraviolet detection (UV) as described in the American Pharmacopoeia, using the USP quercetin standard. A content of 101.4% was observed for the quercetin raw material. Accelerated stability has 100.1%, 117.2% and 101.5%, while long-term stability has 99.97%, 104.8% and 100.7%, respectively, at times T0, T3 and T6.
Humidity was measured by the Brazilian Pharmacopoeia method, using the Karl Fischer equipment. For both, raw material and bars, the results are in accordance with the ANVISA specification(4), which recommends that food humidity does not exceed 15%. The raw material presented humidity of 1.5%. In the accelerated stability, the cereal bars humidity values were 11.2%, 10.4% and 10.6%, while the long-term values were 11.7%, 10.4% and 10.7%, respectively, at times T0, T3 and T6.
The microbiological study(5) evaluated the presence of Bacillus cereus (direct counting method in Mannitol Egg Yolk Polymyxin Agar, with maximum limit of 5 x 102 CFU/g), coliforms 45 ºC maximum 5 x 10 MPN/g (counting method in Red Violet Bile Agar) and Salmonella sp (absence/25g, classic culture method in Xylose Lysine Deoxycholate Agar). All samples analyzed attended the recommendations of ANVISA.
In conclusion, the analyzed formulation complies with the current legislation, having potential for registration as a functional food.

References: (1)Lin et al., Journal of Functional Foods, 40:299-306, 2018; (2)Perez et al., Pharmacological Research, 89:11–18, 2014; (3) Brasil. ANVISA. Agência Nacional de Vigilância Sanitária. Resolução da Diretoria Colegiada (RDC) nº 360/2003; (4)RDC nº 263/2005; (5) RDC nº 12/2001.