Abstract: The nutritional composition of potato-rice wines made from glutinous rice, fresh potatoes and their mixtures in different proportions (25:75, 50:50 and 75:25) was determined, and their volatile aroma compounds were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry to study the influence of potatoes on the nutritional composition and aroma compounds of rice wine. The results showed that addition of potatoes to rice greatly increased dietary fiber content, and enhanced vitamin C content from 0 to 3.95 mg/100 g and alcohol content from 0.64% to 3.34% compared with pure rice wine. Potato addition reduced sugar-to-acid ratio and the total amount of amino acids but increased the amount of tryptophan, and improved the amino acid composition of rice wine. A total of 61 aroma compounds were identified in all wine samples, mainly including isoamylol, isobutanol, phenylethyl alcohol, hexanol, ethyl palmitate, isoamyl acetate, ethyl caprylate, acetic acid, hexanal, acetoin, β-caryophyllene, and 2-amylfuran, and 67% of these compounds were alcohols and esters, whose amount together accounted for over 80% of the total aroma compounds. In potato-rice wines made with 0%–50% and 75% potatoes, isoamylol and phenylethyl alcohol were the most abundant aroma components, respectively. Principal component analysis (PCA) indicated that addition of different levels of potatoes had a great influence on the aroma composition of rice wine. In general, addition of proper amounts of fresh potatoes (25%–50%) could impart well-balanced nutritional composition, improved taste and abundant aroma compounds to potato-rice wine.

Key words: potato, glutinous rice, rice wine, gas chromatography-mass spectrometry, aroma compounds