Enhancing shelf-life and sensory quality of Kachagolla (sweet cottage cheese truffles) through jamun seed and coconut sugar substitution

Kachagolla is a traditional Indian sweetmeat. It has a concise shelf life at room temperature (1–2 days after preparation). Jamun seeds (Syzygium cumini) are widely recognised for their antibiotic, antihyperglycemic, and antioxidant activity. Likewise, coconut sugar, with a low glycemic index, is healthier than most off-the-shelf sugars. This study was conducted to determine the effect of jamun seed powder (JSP) and coconut sugar (CS) fortification on the sensory attributes and shelf life of normal Kachagolla (NK). Since food colour is an essential component to draw customers’ attention, Box–Behnken design (BBD) was considered to obtain ideal optimal parameters for maximising total colour difference (ΔE) of the developed jamun seed-fortified Kachagolla (JSK). RSM optimisation revealed that a fixed microwave power level of 600 W, a 30% CS, and a 2% JSP were the optimum parameters. The polyphenolic content, antioxidant activity, physicochemical, functional, colour, textural, and organoleptic quality of Kachagolla were also estimated. The findings demonstrated that the total polyphenol content (TPC) and ABTS activity of JSK were significantly higher (p < 0.05) compared to NK. A 2.71% increase in hardness was observed in Kachagolla after fortification. HPLC analysis revealed a significant increase (p < 0.05) in phenolic acids in JSK samples. Throughout the 7-day storage period, it was found that the JSK samples exhibited significantly lower (p < 0.05) lipid oxidation activities compared to those of NK. Based on microbiological and sensory studies, it can be inferred that JSK can be stored for 5–6 days longer at room temperature than NK.