Fruit Leather Production From Fermented Aronia (Aronia melanocarpa) Fruit By Traditional Methods And Hydrocolloid Incorporation And Determination Of Quality Characteristics
Project no. 28415 · Status: Kapanmış (Yayın bekleniyor) · 2023
Summary
<p>In recent years, with changing living standards and consumer trends, people's healthy eating habits are diversifying which leads them to discover new products. Aronia berry, known for its strong antioxidant activity and rich polyphenol content, is a preferred type of berry in healthy eating programs. It is consumed fresh and also processed in the food industry. Today, aronia berries, cultivated in many countries, are transformed into various products within the traditional product sector, an effective segment of food consumption. One of these traditional products is pestil, defined as an industrially produced alternative fruit snack that can be made from various fruits.</p><p>In this thesis, fruit leather was produced from fermented aronia fruit with the aim of increasing its consumption outside of the harvest season and developing health-beneficial products as an alternative to the products currently on the market. Initially, fresh aronia fruit was homogenized into a puree, prepared as a fruit puree and a diluted fruit puree (1:1 w/v). Subsequently, fermentation trials were conducted for 9 days at 28°C, using different inoculation rates (1%, 2%, and 4%) of <em>Saccharomyces cerevisiae</em> spp. and adding varying amounts of sucrose (0%, 5%, 10%, and 20%). To examine the effect of various fermentation parameters on the bioactive components of the fruit, pH and bioactive component levels were measured every 3 days. Based on preliminary trials, the optimal production conditions were determined to be fermentation of the pureed aronia fruit with 4% inoculum in a sugar-free medium for 3 days.</p><p>Next, fruit leathers were prepared from fresh and fermented aronia fruit purees by adding different ratios of starch (4%, 6%, and 8%) and xanthan gum and guar gum (1%, 1.5%, and 2%), and they were dried in a drying cabinet at 55°C with an airspeed of 1.5 m/s. After the drying process, the physical and chemical properties of the resulting products were compared, and the best fruit leather formulations were determined.</p><p>According to the results, after fermentation, the total phenolic content of fresh aronia fruit increased by 34%, flavonoid content increased by 35%, and total monomeric anthocyanin content increased by 21%. Furthermore, fruit leathers made from fermented fruit had 22-36% higher total phenolic content, 25-55% higher flavonoid content, and 41-45% higher total monomeric anthocyanin content compared to fruit leathers made from fresh fruit puree. When the color values of the fruit leather samples were measured, it was found that the lightness (L*) value (20.89 ±0.1) of the fruit leathers produced with 4% starch from both fresh and fermented fruit was higher than those produced with other hydrocolloids (guar gum and xanthan gum). The samples with the highest redness value were found to be the ones produced with 1% guar gum (1.33±0.2).</p><p>In conclusion, it was determined that the fermentation process increased the amount of bioactive components in aronia fruit and fruit leathers. It was also found that the fruit leathers prepared with hydrocolloids had higher water retention capacities, shorter drying times, and better preservation of bioactive components.</p>