Investigation of some physical, chemical and sensory properties of dairy products obtained using sumac (Rhus coriaria L.)

Spice varieties that make up different parts of the plant are very often preferred to give aroma and taste to the dishes. Various beneficial plants have properties such as providing an antimicrobial effect thanks to their high antioxidant capacity. Therefore, it is thought that fortification of dairy products may help to provide functional and alternative dairy products with high nutritional value. In this study, it was aimed to test the use of sumac (Rhus coriaria L.) to coagulate milk and to test the use of whey (PAS) as a substitute for milk in ice cream production in order to prevent food waste, and to reveal how sumac spice affects the physicochemical and sensory properties of ice cream. For this purpose, coagulation with sumac added to milk after boiling was successful in preliminary trials. The amount of sumac used in coagulating the milk was fixed at 2.5%. Whey obtained after coagulation of milk with sumac was used instead of milk in the ice cream mix. 2.5%, 5%, 7.5% sumac was added to the mixes prepared using sumac whey. The final data were compared by applying various physicochemical analyzes in the laboratory environment and sensory evaluation with the participation of 80 people in the produced curd cheese, whey, ice cream mixes and ice creams. Considering the findings obtained in the analyzes applied in the research, the dry matter amount of sumac used to obtain curd in curd cheese production varies from 45, 14 to 52.90, the ash amount is from 0.93 to 1.94, and the a* value is 22.80, compared to plain curd cheese. It was observed that it increased the L* value from 94.41 to 39.48 and the b* value from 14.49 to 10.23. In terms of sensory properties, curd cheese with sumac received a higher rating with 6.73 points than plain curd cheese, which received 6.46 points in the general acceptability criterion. In the sensory analysis, the most significant difference is in the attractiveness criteria with 7.13 in sumac curd cheese and 5.93 in plain curd cheese. When the whey obtained is compared, the pH value of the sumac used is from 5.09 to 5.03, the L* value from 76.40 to 43.11, the a* value from 17.29 to 12.29 and It is noted that it decreased the b* value from 20.08 to 4.60. The pH value of the sumac whey and sumac added iv samples used in ice cream mixes varies between 4.12-5.76, L* value is 57.58-88.54, a* value is 3.95-23.45, b* value is 4, It varies between 14-24.61. When looking at the ice cream samples produced with plain whey and sumac whey, L* values are 58.95-84.48, a* values are -0.35-22.67, b* values are 9.13-17.72, dry matter amounts are 28.38 -37.33, ash amounts 0.58-1.43, volume increase rate 40.69-48.96, melting rates vary between 33.80-71.03 at 60th minute. The use of whey with sumac and the addition of sumac decreased the L* and b* values in direct proportion and increased the a* value. The ice cream sample produced using sumac whey without adding sumac provided the highest rate in terms of volume increase. In terms of melting rate, the ice cream sample produced using sumac whey without adding sumac showed the most positive feature by not melting even at 30 minutes. The ice creams produced with additional sumac also showed a lower melting rate than the ice cream produced with plain whey. According to the sensory analysis results of the ice creams, color criterion 7.20-8.13, odor criterion 5.93-6.93, taste criterion 5.2-7.40, appearance criterion 7.27-8.13, texture/mouth feeling criterion 4.80-7.40, general acceptability criterion 5.2-7.6, taste suitability criterion 4.66-7.2, attractiveness criterion 6.2-7.13, food culture suitability criterion 5.07- It varies between 7.13 points. Among the ice creams produced with plain whey and sumac whey, the ice cream produced with sumac whey received higher appreciation in terms of taste, attractiveness, palatability and especially smell. Among the ice creams produced by adding different amounts of sumac, the ice cream with 2.5% sumac added the highest scores in terms of colour, suitability for food culture, attractiveness, general acceptability, texture/mouthfeel and appearance. When all of the produced ice creams are evaluated sensorially; The most popular ice cream in terms of taste, smell, attractiveness, palatability and general acceptability was ice cream produced with sumac whey without the addition of sumac. Key Words: Sumac (Rhus coriaria L.), Whey, ice cream, coagulation of milk, sensory analysis, physicochemical analysis