Quality and Sensory Characteristics of Hard Red Wheat after Residential Storage for up to 32 Y

Abstract

Samples of hard red wheat packaged for long-term storage, ranging in age from 0 to 32 y, were obtained from donors in residential households. All samples had been stored under nonabusive conditions (7% to 10% moisture, 13 to 27 °C). Selected quality parameters of the wheat (moisture, thiamin, free fatty acids, flour extraction rate, bread loaf volume, and bread firmness) and sensory properties of bread made from the stored wheat (aroma, appearance, texture, flavor, overall liking, acceptance for use as part of the regular diet, and acceptance for use in emergency situations) were evaluated. Free fatty acids increased significantly from 0.897 to 11.8 μmol/g, and flour extraction rate decreased significantly from 76.5% to 69.9% over time. None of the other quality parameters measured (moisture, thiamin, bread loaf volume, and bread firmness) were significantly correlated with wheat storage time. Panelists who frequently or occasionally consume whole wheat bread rated all breads made from the stored wheat with hedonic scores (9-point scale) of at least 6.4 (like slightly to moderately). Consumer ratings of bread texture, flavor, and overall acceptability were negatively correlated with storage time (P < 0.001); however, at least 70% of panelists indicated that they would consume the bread as part of their regular diet even after 32 y of wheat storage, while over 97% would do so in an emergency. These data indicate that wheat maintains nutritional quality and makes acceptable bread when stored up to 32 y at 13 to 27 °C and 7% to 10% moisture. Practical Application: Wheat stored for the purposes of disaster relief has the potential of being stored for extremely long periods of time, which may result in undesirable changes in milling and baking quality. Therefore, we tested wheat that had been stored under residential conditions for up to 32 y to determine its functional quality and consumer acceptability. Our results indicate that wheat of low moisture (7% to 10%) packaged in sealed cans and stored for up to 32 y at or below typical room temperature retains quality and can be made into bread that is well accepted by consumers. Thus, whole wheat has good long-term storage stability and can be recommended for emergency food supplies.

Key issues and challenges in whole wheat flour milling and storage

“…Low molecular weight carbohydrates in dough increase bread crust coloration due to the Maillard reaction (Pomeranz, 1988). However, whole wheat bread made from flour or wheat stored for extremely long periods of time may exhibit more pale crust rather than a darker crust (unpublished observations while preparing bread for Rose et al, 2011). This may be due to reduction in amino acids available for the Maillard reaction.…”

Sensory, yield and quality differences between organically and conventionally grown winter wheat

“…The samples on day 2 of the FiBL panel were from the 2009 harvest and thus had only been stored for 3 months whereas the other samples (SAM day 1 and day 2, FiBL day 1) had already been stored for 2.5, 1.5 and 2.25 years, respectively. Wheat is known to maintain quality over many years when stored under non‐abusive conditions, but even under optimal storage conditions, some degradation of fatty acids occurs 45. Thus, ageing during storage may have contributed to reduce sensory differences.…”