Effect of partial substitution of wheat flour with Tamarind seed flour on physical, chemical, antioxidant and sensory properties of noodles

Abstract

Tamarind (Tamarindus indica L.) fruit are a major crop of Thailand and many other countries. Tamarind fruit are used in food processing, but their  seeds, which constitute about 34% of each fruit, are largely a wasted byproduct. Production of fresh noodles, using flour made from tamarind seed (TSF) as a partial substitute for wheat flour, was tested. The proportion of TSF in the flour was varied from 0, 5, 10, 15 and 20%, with the balance being white wheat flour. Results showed that with increasing the levels of TSF in the flour there was a concomitant increase in their carotenoid content, but 15% resulted in negative responses from the sensory evaluation panel due mainly to darkening and browning of the color of the noodles and making them less soft and less elastic. These perceptions by the panelists were reflected in the measurement of L*, a* and b* and the tensile force of dough and tensile strength of cooked noodles. When the noodles made from 10% TSF plus 90% wheat flour were tested, their moisture content, protein, total carbohydrate, fat and ash were 70.6, 6.26, 21.5, 1.08, 0.490 g/100g and calories was 121 kcal/100g, respectively and their mineral contents were calcium, magnesium, phosphorus, potassium and sodium at 16.0, 14.4, 45.3, 27.2 and 130 mg/100g, respectively. Total phenolic content and antioxidant activity also progressively increased with increasing levels of TSF in the flour. The total phenolic content from noodles made from 10% TSF plus 90% refined wheat flour were 7.92 mg GAE/g, antioxidant activity was 29.6 mM TE/g by ferric reducing antioxidant power, 17.1 mM TE/g by 2,2 diphenyl- 1-picrylhydrazyl assay and 3.84 mM TE/g by 2,2'-azino-bis (3-ethylbenzothiazo line-6- sulphonic acid). The descriptive analysis of eight trained panelists discovered 16 individual attributes of cooked noodles made from 10% TSF plus 90% wheat flour.
These attributes were yellowness, turbidity, egg odor, flour odor, tamarind flour odor, roasted tamarind seed odor, alkaline odor, egg flavor, flour flavor, tamarind flour flavor, roasted tamarind seed flavor, bitter taste, wetness, smoothness, softness and elasticity. The descriptive analysis showed that the cooked noodles containing 10% TSF had similar characteristics to cooked noodles made from 100% wheat flour except for roasted tamarind seed odor, tamarind flour flavor and roasted tamarind seed flavor that were unique characteristics, as would be expected.

Key words: Antioxidant activity, Chemical properties, Noodle, Sensory attributes, Tamarind seeds flour