Quality and safety of halawa modified with mushroom

Halawa supplemented with 10-120 g mushroom, was evaluated for its acceptability (color, taste, texture, separate oil and overall acceptability by a ten-member panel), protein content (as amino acid content), microbiological safety and quality. Halawa supplemented with both 10 and 20 g mushroom was equally as acceptable as the unsupplemented halawa in most sensory attributes. Results indicated that the low percentage of mushroom in halawa and control samples gave a higher panel score of all organoleptic characteristics than the high percentage of mushroom in halawa samples after 6 months storage at room temperature (25 °C). This result indicated that mushroom addition could prevent defects like oil separation and non-coherence in halawa. It would be logical to expect a strong correlation between the sensory measure (color) of halawa and color parameters obtained by instrumental determination as well as non-enzymatic browning (A(420nm)). Techniques of regression analysis were used to predict the coefficient of correlation between the visual color score and each of the seven color parameters. The estimated values of RSQ was found to range between 0.97 (in the case of H*) to 0.98 (in the case of a*). The results showed that the aerobic plate counts increased during first the 2 months, and then decreased during the storage period for halawa fortified by different percentages of mushroom. Lipolytic microorganisms did not change during storage and remained in low numbers for halawa fortified by mushroom. Results revealed that all samples of halawa fortified by mushroom were free from clostridia, total Enterobacteriaceae count and pathogenic bacteria (Salmonella spp. and Staphylococcus aureus). It was concluded that halawa in the presence of mushroom was useful for minimizing the extent of Maillard browning reaction, maintaining color characteristics and parameters, maintaining quality and reducing water activity, and in increasing shelf-life through inhibiting the bathogenic and reducing the spoilage bacteria.