Effect of Addition of Spelt and Buckwheat Hull on Selected Properties of Yoghurt

Abstract

Buckwheat and spelled hulls are little tested in their use in the production of functional foods. The aim of this study was to evaluate the use of hull as a functional additive in yoghurt and to determine the effect of various doses of buckwheat and spelt hull on the physicochemical, organoleptic and microbiological properties of yoghurt. The enrichment of yoghurt with buckwheat and spelled hull resulted in a decrease in total acidity and a decrease in syneresis. Addition of spelt and buckwheat hulls to yoghurts reduced the colour brightness and increased the intensity of the red and yellow colours. The highest number of S. thermophilus was found in yoghurt containing 3% buckwheat hull and the beneficial effect of the addition of hull on L. bulgaricus growth was demonstrated. The type of hull determined the flavour and odour of yoghurts. Spelt hull gave the yoghurts a more intense floury and grainy flavour than buckwheat hull.

The Influence of Hazelnut Skin Addition on Quality Properties and Antioxidant Activity of Functional Yogurt

“…In general, the pH values of yogurts enriched with hazelnut skin were higher than control yogurts, and these differences were found to be statistically significant (p < 0.05) between the control and C groups. The results are consistent with those published by Buniowska et al (2020) [16], who found the highest pH value in yogurt enriched with 3% spelt hull, and the lowest in the control. In addition, Ozturkoglu-Budak et al (2016) [11] obtained similar results and indicated that all dried nut-(walnut, hazelnut, almond, or pistachio) fortified yogurts had higher pH values than that of the control yogurt.…”

“…A better water-holding property of enriched yogurts may be explained by the high content of the insoluble dietary fibre in the hazelnut skin. This was also confirmed by other authors, who found that the WHC of yogurts was increased by addition of rice bran [34]; yogurts with buckwheat and spelt hulls had lower syneresis values as compared with the control [16].…”

“…This situation is also compatible with the pH values of yogurts. In another study, the yogurts enriched with buckwheat and spelt hull had lower total acidity than that of the control, and the increase in the dose caused even lower acidity [16]. The higher pH and lower acidity obtained in the current study could be due to the dietary fibre coming from hazelnut skin.…”

“…Lower instrumental texture parameters of enriched yogurts were previously observed in other studies, in which different types of by-products were used. The use of pineapple peel powder [12] and the use of spelt and buckwheat hull at a dose of 1.5% [16] also resulted in lower hardness of yogurt. This may be due to a weak gel, attributed to thermodynamic incompatibility between milk proteins and polysaccharides from by-products.…”

“…In addition, the incorporation of hazelnut skin, which is a fibre-rich by-product, into yogurts represents means of augmenting the consumption of fibre, owing to the popularity of this foodstuff. Studies have shown that high-fibre yogurt consumption has health benefits, such as reduction in the risk of obesity, diabetes, cancer, hypertension, hypercholesterolemia, and cardiovascular and gastrointestinal disorders and also promotes intestinal microflora and gastrointestinal immunity [15,16]. As fibre deficiency in the diet may cause many nutrition-related diseases, an average daily intake of 25 g of fibre is recommended by the European Food Safety Authority [17].…”