Taste and Odor Changes During Fat Rancidity Development in Wheat

Abstract

Many Americans are interested in eating foods which are natural and do not contain additives. Storing wheat in the refrigerator/freezer or properly drying wheat help prolong the shelf life. Home processed wheat may become rancid before it is consumed because the commercial methods for preserving wheat may not be available in the home. The development of fat rancidity in wheat stored at room temperature (23°C and 70% relative humidity) was measured by testing fat acidity development in the whole grain and flour forms of ‘Guard’ and ‘2371’ cultivars of wheat. To examine the sensory acceptability of bread made from this wheat, bread was baked from the two types of flour for 11 weeks. The bread was evaluated for taste and odor acceptance using a 5-point hedonic rating scale. According to the literature rancidity standard, the flour was rancid within 10 days of harvest but the taste and odor of the bread were acceptable for 32–66 days post-harvest or until the fat acidity level was six times the literature standard. Large amounts of freshly harvested wheat should be dried and stored in the whole grain form to slow rancidity development. When stored at room temperature, high quality whole grain will not become rancid for about 44 days. Wheat should be milled in small batches that will be used within a month. The consumer taste panel was able to consume bread in which the rancidity level was six times the literature standard.