STUDY ON PHYSIOLOGICAL AND BIOCHEMICAL PARAMETERS OF SACHA INCHI LEAF (Plukenetia volubilis L.) AND THE PROCESS OF MAKING TEA BAGS IN VIETNAM

DOI: 10.18173/2354-1059.2023-0072

Tóm tắt

The study consists of two experiments, the first one aims to determine the number of growth and physiological parameters of sacha inchi leaves (content of tannins, reducing sugars, minerals) to provide a basis for choosing leaf type (according to age) for the second experiment: a study on the effect of temperature and drying time on the perceived results of tea bags made from sacha inchi leaves as well as to find out the mixing ratio between sacha inchi leaf combined with licorice and pandan leaves to make a tea bag which has good sensory quality and quality in the tests. The main experimental methods used in this study were: Determination of the total chlorophyll content in sacha inchi leaves by using handheld chlorophyll meter; The dry weight of leaf samples was determined based on the dry weight after drying at 105oC for 1 day 1 night by analytical balance; The content of tannins in the leaves by leventhal method also was measured; Minerals such as Mg, Ca and K were determined by wetting of leaf samples and measured with an AAS atomic absorption spectrometer. The factors affecting the quality and sensory of tea bags such as temperature tea drying time, and mixing ratio of sacha inchi: licorice: pandan leaves were also investigated. A study on the extraction time of tea solution for phenolic content and oxidation activity of finished tea product was also carried out. The results showed the highest concentration of tannins in old leaves (2.47 ± 0.02 % by dry weight) and lowest in young leaves (2.17 ± 0.02 % by dry weight), the highest concentration of reducing sugars in mature leaves (25.9 ± 5.67 mg/g). The concentration of mobile minerals such as Mg, and K was highest in young leaves (0.75 ± 0.04 and 33.62 ± 0.98 mg/kg, respectively) and lowest in old leaves (0.61 ± 0.01 and 29.41 ± 0.12 mg/kg, respectively) while non-mobile minerals as Ca were highest in old leaves (32.59 ± 0.16 mg/kg) and lowest in young leaves (28.27 ± 1.02 mg/kg). The phenolic content was highest and the antioxidant capacity SC50 was lowest in a 5-minute tea extract solution (126.2a ± 8.9 mg gallic acid/1g and 4.34 ± 0.5 mg/ml. The tea treatment with the highest sensory survey results was the mature leaf sample, which was dried at 130℃ for 1 hour, with a mixing ratio of sacha inchi leaves: licorice leaves: pandan leaves of 1.6/0.4/0.2 for tea packages with a dry weight of 2.2 g/bag and extract the tea bag in hot water in 5 minutes is our recommendation.