Extending Shelf Life of Noughl by Modifying Relative Humidity of the Container: Study of Physicochemical and Textural Properties

Abstract

Dehydration of Noughl, as a sugar-based confectionary product, negatively affects its texture which can be hindered by increasing relative humidity (RH) of atmosphere of storage container. In this research, glucose syrup (GS) and its mixture with salt at different ratios (8:1, 4:1 and 2:1) was utilized as RH-modifier inside the storage container in order to prevent hardness of Noughl. The effect of RH-modifiers on moisture, hardness, area and color of samples was investigated during 30 days. Color and area changes of samples were measured using image processing. According to the findings, the lowest change in moisture content, color and area of saffron Noughls was observed when GS-salt mixture was used at the ratio of 8:1. It is found that the RH-modifier could re-increase the RH of container internal space after opening and reclosing lid of the container for 29 times. Furthermore, hardness of Noughls was hindered since the average hardness values were 32.40 and 23.38 N on zero and 30 days, respectively. However, hardness of control sample reached to 149.85 N on day 5. Based on sensory evaluation, there was no significant difference between the overall acceptability of fresh Noughls and those stored for 30 days (P<0.05). The introduced low-cost RH-modifier can be applicable for different foodstuffs to prevent dehydration.

Keywords

• glucose syrup
• image processing
• moisture loss
• noughl
• relative humidity-modifier