Paste production and optimization of apricot kernel press cake

In this study, the production possibilities of a new value-added press cake paste from the press cake, which is seen as a waste product in the apricot kernel oil industry but is a vegetable protein source, was investigated. The study consists of two parts. In the first part, the responses of the independent variables (sugar/water and sherbet/press cake) that make up the paste formulation to the sensory and texture dependent variables were evaluated and optimization was achieved by using the response surface method. The samples of the crusted press cake determined as a result of the optimization were coded as 1 and 2. After the experimental and estimated results were verified, the actual production of the press cake paste was carried out. The paste obtained from unshelled apricot kernels was included in the study as control sample number 3. In the second part, the paste samples produced according to the optimum formulations were stored at three different temperatures as 22°C, 35°C and 45°C for accelerated shelf life testing. Physicochemical, microbiological, textural, sensory and shelf life analyzes (free fatty acidity and peroxide value) were performed on the 1st, 15th and 30th days of storage. The highest protein content was found as 30.79% in crusty press cake paste. A decrease in humidity, aw, pH results, and an increase in free fatty acidity and peroxide values were observed depending on temperature and storage. According to microbiological analysis, while total yeast-mold and coliform bacteria groups were not found, the total number of bacteria decreased slightly with temperature and storage. Apricot kernel press cake paste containing 1.17 L/kg sherbet/press cake had the highest results in terms of sensory and texture. The peroxide value was determined as the critical parameter for the shelf life test and the shelf life of the samples at low temperatures was estimated according to the values in the samples that deteriorated rapidly at high temperature. As a result of the shelf life estimation created by using the peroxide value, the shelf lives of the samples 1, 2 and 3 were found to be 123.2, 125.17 and 97.92 days, respectively. As a result, it has been determined that the apricot kernel press cake paste obtained for waste product evaluation can be consumed as an alternative product and plant-based protein source, together with storage at room conditions.