Process Optimization for Formulating Trigonella foenum-graecum and Gymnema sylvestre Added Vegetable Cereal Mix Using Response Surface Methodology

Abstract

Abbreviations: ANOVA, analysis of variance; CCD, central composite design; CV, coefficient of variation; R 2 , regression coefficient; RSM, response surface methodology IntroductionTrigonella foenum-graecum (fenugreek seeds) and Gymnema sylvestre (gurmer leaves) have some significant health benefits. 1-3Trigonella foenum-graecum seeds play important role in antidiabetic activity. They have high mucilaginous fiber content, alkaloids (i.e., trigonelline, gentianine, capaine), sapogenins (yamogenin, gitogenin, neotigogens), high protein and micronutrient content.4,5 These seeds contain a unique free amino acid 4-hydroxy isoleucine (4-OH-lle) that has been characterized as one of the active ingredients for blood glucose control.6 They are used to prepare extracts or powder for different medicinal uses 7 due to their hypoglycaemic, 8 hypocholestrolemic, 9,10gastro-protective, anti-inflammatory, 11,12 anti-ulcer 13 and anticarcinogenic 14 properties. They enhance insulin release in body. 15Several experimental studies have confirmed the antidiabetic potential of Trigonella foenum-graecum. [16][17][18] Twenty five g of Trigonella foenum-graecum seeds powder (divided into two equal doses) have been used to treat diabetes mellitus. [19][20][21][22] Flour fortified with 8-10% Trigonella foenum-graecum has been used in formulation of different bakery products, i.e., bread, cakes, muffins and pizza with acceptable sensory properties. 23 These seeds are relatively safe 24 and have no genotoxicity.6 Gymnema sylvestre is an Indian herb used in Ayurvedic treatment (the traditional Hindu system of medicine) due to its pharmacological properties, i.e., hypoglycemic, hypocholesterolemic, hypotensive, antiobesity, antimicrobial, free radical scavenging and anti-inflammatory. 25,26 It is promoted as a 'sugar blocker' in US markets. 27,28 It is a potential natural alternative to chemical means of blood sugar regulation.29 It enhances the endogenous insulin production by increasing the number of β-cells in pancreas. [30][31][32] Leaves of Gymnema sylvestre contain glycosides, gymnemic acid, saponins, phytosterols, phenols, flavonoids, tannins and quercitol.33,34 Dosage of Gymnema sylvestre used in Ayurvedic medicine varies between 6 to 60g of dry or powdered leaf per day. [35][36][37] Trigonella foenumgraecum are bitter in taste, thus, their incorporation in high quantity can compromise overall acceptability of formulated food product. Therefore, techniques are required to produce optimum solutions for formulation of nutritionally adequate and organoleptically acceptable food product. One such technique is process optimization which can be used for development of optimum foods with enhanced nutritional AbstractTrigonella foenum-graecum seeds and Gymnema sylvestre leaves are health promoting food ingredients which are particularly beneficial for individuals suffering from diabetes mellitus. In order to promote their incorporation in diet, vegetable cereal mix was formulated as a dried food product with extended shelf life, which could...