Effect of Lupin (Lupinus albifrons) Flour on Microbial and sensory properties of local Yoghurt

Abstract

This study conducted and implicated in the General State Company for Dairy Products, Abu-Ghraib/ Baghdad/Iraq in February to April /2014. Two different sweet lupin seed (Jordanian, Egyptian) origin were used for this study which been imported from the local markets.

Soaking and boiling process (de- bittering process) of lupin seeds was used to destroy thermo-labile anti-nutritional factors, such as trypsin inhibitors, phytic acid and to soften the seed.

It was been found that, the concentration (2, 4, 6)% of lupin seed supplementation for each origin (Jordan and Egypt) are the best in dairy product supplementation after conducting many different tests to see the best degree of agreement by the specialized panelists in the dairy company.

The physicochemical analysis of the supplemented yogurt with different concentration (2, 4, and 6) % of Jordanian and Egyptian lupin flour showed that, it does not affect the percent of fat content statistically. But, there were clear positive statistical significant differences in the total solid. Also, there were statistically positive correlation between lupin flour concentration addition and total solid of the yogurt product which does affect directly the texture of the yogurt. There were statistically positive correlation between lupin flour concentration supplement and the pH of the yogurt product which does affect directly the flavor and taste of the yogurt product by the consumers. Thus, increasing the concentration of the supplementation with lupin flour lead to decrease the acidity and increase the pH in yogurt products significantly.

Sensory evaluation of the supplemented yogurt product were showed that the 2 and 4% of lupin flour for both origin were the highest positive effect on physicochemical and sensory scores (flavor, taste, acidity, texture and consistency, appearance, and the total properties). Also, it was found that, the period of storage (1-14 days) did not affect the physicochemical and sensory evaluation clearly of the supplemented lupin dairy product.

Therefore, we recommended the possibility of supplementation of yogurt with sweet lupin flour for its healthier and structural effect on human health to these kind of products.

Keywords: Dairy product, Supplementation, Lupin flour, Physicochemical properties, Sensory evaluation, microbial content.