Rheology of Muffin Batters by Line Spread Test and Viscosity Measurements
This work was aimed to quantify the flow properties of muffin batters by Line Spread Test (LST) and to establish a valid correlation between their line spread distance and viscosity. LST is a quick and inexpensive method for comparing relative viscosities of food slurries or a solid-liquid suspension type of food materials, like muffin batters. The rheological proper ties of muffin batters formulated using gluten free flours were studied. Five different combinations of rice flour and quinoa flour were studied as gluten free flour combinations. Control muffin batters were formulated using 100% wheat flour, which is a gluten positive flour. Density, pH, line spread distance and viscosity were measured for all six batter formulations including control. All tests were performed in triplicate and all data were analyzed statistically. In general, gluten free flour reduced the density and increased the acidity of muffin batters. Whereas, line spread distance was increased and viscosity was decreased with replacement of quinoa flour to rice flour in the muffin batters. A valid correlation between line spread distance and viscosity was observed. The inverse of LST in cm/sec was observed to be close to the viscosity in poise for muffin batters in this study.
Preservation of Chocolate Muffins with Lemon Balm, Oregano, and Rosemary Extracts
Muffins are snacks made from flour and chocolate and preserved with synthetic additives. Following consumer trends, the search for natural food additives has gained traction. Plants such as rosemary, lemon balm, and oregano were analyzed following an optimization of ultrasound assisted extraction, screened for their antioxidant and antimicrobial activity and incorporated in chocolate muffins, comparing them to synthetic preservatives over the course of 8 days. The nutritional profile, organic and fatty acids, soluble sugars, texture profile, external color and digital imaging of the muffin pores were analyzed. Slight changes were sought for the muffins incorporated with the natural extracts. By means of linear discriminant analysis, rosemary extract was considered the most promising extract to preserve the muffins due to its similarity to potassium sorbate, showing no changes in the muffins it was incorporated in, although it showed a lower amount of phenolic compounds when compared to lemon balm.
Amylose and Lipid Contents, Amylopectin Structure, and Gelatinisation Properties of Waxy Wheat (Triticum aestivum) Starch
Abstract Starch was isolated from the endosperm of three recently developed waxy wheat lines and their parents. Their amylose and lipid contents, amylopectin structures and gelatinisation properties were evaluated. The endosperm starch from waxy wheat lines is composed essentially of amylopectin. The apparent amylose (1·2–2·0 g/100 g) and lipid contents (0·12–0·29 g/100 g) are much lower than the apparent amylose (26·0–28·4 g/100 g) and lipid contents (1·05–1·17 g/100 g) of their non-waxy parents. The amylopectin of waxy wheat lines is structurally identical to that of the parents. The peak gelatinisation temperature and gelatinisation enthalpy for waxy starch are significantly higher than for non-waxy starch, but the gelatinisation enthalpy for the amylopectin fraction of waxy starch is nearly identical to that of non-waxy starch.