Determination of the shelf life of puffed wheat "Badyrak vanilla" and "Badyrak with whey"

Puffed grains made from whole grains of wheat, corn or rice are ready-to-eat breakfast cereals, which do not require additional preparation. Sweet-coated puffed wheat has become very popular among consumers. Two recipes for puffed grain coatings were developed – puffed grain with vanilla flavour “Badyrak vanilla” (BV) and puffed grain with whey “Badyrak with whey” (BMS). The addition of whey enriched the product with vitamins B1, B2 and B6, as well as essential amino acids. In the application of coating, oil was used. Deterioration of oil may be limiting factor for shelf life of the developed products. Therefore, the aim of this study was to determine the changes in the acid value of lipids during storage to establish the shelf life of sweet-coated puffed wheat grains. The products were packaged in the sealed pouches of metallized polypropylene (MetPP), 30 g each. The acid value was studied monthly according to the standard GOST R 52466-2005 in products during their eight month storage. The studies were carried out at different storage temperatures (20±2 °С, 4±2 °С, and minus 18±1 °С). Literature studies and organoleptic evaluation of puffed wheat allowed setting limiting acid value at 4.0 mg gE−1 of fat. When acid value exceeded the limit, the overall organoleptic quality was reduced, primarily due to the changes in aroma and the appearance of an unpleasant aftertaste. The increase of acid value was storage temperature dependent. The highest acid value after eight-month storage was established for samples stored at 20±2 °С, being 4.5 mg gE−1 of oil for BV and 5.2 mg gE−1 of oil for BMS. The study allowed recommending 4-month shelf life for "Badyrak with whey" and 5 months for “Badyrak vanilla”.