Utilization of guava seeds [Psidium guajava L.] in some food products

ABSTRACT

ANALYSIS of guava seed powder revealed that guava seed contained ether extract 7.97%, protein 9.37%, crude fiber 57.6%, dietary fiber 79.37%, lignin 20.37%, cellulose 41.28% and hemicellulose 17.7%. The characteristics of guava seed oil were, acid value 0.85 mg [KOH/g oil], peroxide value 1.15 [meq O[2]/kg oil], saponification value 185.23; unsaponifiable matter 1.21% and iodine value 119.5 [g I[2]/100g oil]. Moreover, the most abundant saturated fatty acid was palmatic. However, the most predominant unsaturated fatty acid was linoleic acid which indicates that the oil is considered as semi drying oil. With regard to protein evaluation of guava seed, results showed that leucine was the predominant essential amino acid with a value of 2.2 [mg/g], while the predominant non-essential amino acid was glutamic acid 6.2 [mg/g]. Biological value of guava seed protein was 56.96 and PER was 0.32. Addition of guava seed powder to rice grits for extrusion caused reduction of the expansion ratio [ER], decrease in the bulk density [BD], slight increase of the water absorption index and decrease in the breaking strength [BS] of the extrudate. The sensory evaluation of the new products indicated that good extrudates were obtained by adding up to 8% of guava seeds powder to rice grits. Adding guava seed powder to semolina flour to produce high fiber macaroni caused decrease in the BS values. The results obtained showed that the absorbed water and solid substance were increased as the level of addition of guava seed powder was increased. The sensory evaluation indicated that macaroni product with excellent and very good grade could be obtained by adding guava seeds powder up to 12%