Impact of Using New Commercial Glutathione Enriched Inactive Dry Yeast Oenological Preparations on the Aroma and Sensory Properties of Wines

Figures & data

Table 1  Evolution of global composition in the must, control wine, and in the wine supplemented with the glutathione-enriched IDY preparation

		pH	TA ^a	PAD ^b	AD ^c	VA ^d
Must		3.2	3.7	13.9	—	—
Cont-W	After alcoholic fermentation	3.13	4.2	—	13.8	—
	Stabilized and clarified wine	3.15	3.4	—	13.75	0.16
GSH-IDY-W	After alcoholic fermentation	3.18	4	—	13.6	—
	Stabilized and clarified wine	3.2	3.25	—	13.5	0.22
^aTotal acidity (g sulphuric acid/L).
^bProbable alcohol degree (% v/v).
^cAlcohol degree (% v/v).
^dVolatile acidity (g acetic acid/L).
Cont-W: control wine; GSH-IDY-W: wine supplemented with the glutathione enriched IDY preparation.

Table 2  Reference standard composition of aroma and taste attributes

	Reference standard composition ^a
Attributes	Low concentration	High concentration
Strawberry	1.5 g of crushed fresh strawberries	6 g of crushed fresh strawberries
Peach	2 mL of peach nectar	7.5 mL of peach nectar
Banana	¼ 10-mm slice fresh banana	10-mm slice fresh banana
Apple	—	Slice fresh apple, 5 mL apple juice
Lemon	—	5 mL lemon juice, and small peel piece of fresh fruit
Floral	0.2 ml of linalool solution (150 mg/L)	1.5 mL of a linalool solution (150 mg/L)
Grassy	—	1 mL of a cis-3-hexen-1-ol solution (100 mg/L)
Toffee	—	1 toffee candy
Raisin	—	2–3 crushed fresh raisins
Honey	—	8 mL honey
Yeast	0.25 g baker yeast	1 g baker yeast
Acidity	0.2 g/L citric acid in water	0.8 g/L citric acid in water
^aReferences were prepared in tasting glasses filled with 25 mL of rosé base wine, covered by petri dishes, with the exception for acidity that was prepared in water. Attributes in bold were finally selected for the study.

Table 3 Concentration of volatile compounds (mean ± standard deviation, μg L⁻¹) determined in the control wines (Cont-W) and in the wines supplemented with the G-IDY preparation (GSH-IDY-W) at 1, 2, 3, and 9 months of aging (1, 2, 3, and 9 m, respectively)

						Cont-W				GSH-IDY-W
	Compounds	RIexp†	Rilit‡	Id§	1 m	2 m	3 m	9 m	1 m	2 m	3 m	9 m
Esters	Ethyl propanoate	920	903	S, R, M	43.9^b±2.6	46.3^b ±5.3	39.5^b,a±6.9	26.8^a ±2.6	26.5^a±0.6	29.3^a±1.2	33^a±0.1	30.9^a±5.1
	Isobutyl acetate	975	953	S, R, M	4.5^b±0.4	4.1^b±0.94	3.3^b±0.7	1.4^a±0.2	5.0^b±0.3	4.5^b±0.0	4.6^b±0.1	2.7^a±0.3
	Ethyl butanoate	1010	1010	S, R, M	240.7^b±12.6	225.2^b±41.6	200.7^b±38.8	103.2^a±22.6	237.8^b±7.2	229.9^b±4.9	242.0^b±2.1	173.2^a±18.9
	Ethyl 2-methylbutanoate	1026	1031	S, R, M	2.5^b±0.1	2.4^b±0.4	2.7^b±0.5	2.5^a±0.2	1.7^a±0.1	2^a,b±0.1	2.2^b,c±0.1	2.6^c±0.2
	Isoamyl acetate	1115	1117	S, R, M	573.7^b±16.6	479^b±75.1	390.1^b±79.5	188.6^a±27.0	811^c±22.5	786.2^c±1.2	730.6^b±3.7	445.9^a±17.3
	Ethyl hexanoate	1229	1230	S, R, M	710.3^b±6.8	582^b±70.8	574.6^b±106.8	310.7^a±28.6	706^b±13.1	722.4^b±7.4	716.6^b±7.5	467.1^a±28.3
	Hexyl acetate	1267	1269	S, R, M	130.7^b±2.06	110.1^b±14.3	97.7^b±19.1	44.9^a±4.7	219.6^c ±6.3	213^c±0.5	194.6^b±1.9	114.5^a±3.5
	Ethyl heptanoate	1327	1332	R, M	2.1^b±0.1	1.8^b±0.2	1.9^b±0.4	1.1^a±0.2	1.4^b±0.1	1.5^b±0.0	1.4^b±0.1	0.8^a±0.1
	Ethyl octanoate	1429	1431	S, R, M	1678.8^b±306.8	1745.1^b±146.2	1788.4^b±145.8	666.1^a±31.7	2097.7^b±8.4	2104.3^b±9.1	2197.4^c±14.7	1046.1^a±13
	Ethyl nonanoate	1530	1541	S, R, M	1.9^a±0.7	3.8^a±0.2	4.6^a±0.2	4.40^a±2.4	2.9^a±0.1	3.6^b±0.0	4.1^b±0.2	2.4^a±0.4
	Ethyl decanoate	1634	1634	S, R, M	511.9^a,b±253.0	883.5^c ±37	864.3^b,c ±47.1	270^a ±15	931.6^b±55	960.3^b±12.7	1045.2^b±56.9	398.4^a±44.3
	Diethyl succinate	1673	1694	S, R, M	515.3^a ±62.7	492.4^a±5.8	788^b ±97.4	1035.8^b±150.8	279.1^a±17.1	300^a±21.3	436.4^a±33.6	800.2^b±230.2
	2-Phenyl ethyl acetate	1809	1752	S, R, M	49.4^b±1.3	53.3^c±0.4	53.6^c±0.4	42.6^a±1.9	89.4^a±5.8	84.2^a±3.7	95.6^a±0.6	63.7^a±23.3
	Ethyl dodecanoate	1840	1833	S, R, M	36.8^a±15.0	72^a±1.8	49.9^a±5.9	97.1^a±40.8	82.3^a±15.5	65.7^a±8.5	52.4^a±4.9	63.5^a±12.7
Alcohols	1-Butanol	1141	1157	S, R, M	394.8^b±9.9	380.6^b ±65.7	343.1^a,b±39.2	226.9^a±37.5	333.7^a±8.3	310.7^a±10.5	361.5^a±10.5	322.4^a±66.9
	1-Hexanol	1353	1356	S, R, M	1255.6^b±100.6	1122.7^a,b±170.9	1102.7^a,b±215	756.4^a±116.8	864.6^a±17.3	718.7^a±15.4	877.9^a±22.4	893.6^a±211.8
	Cis-3-hexenol	1361	1370	S, R, M	44.4^b±3.4	40.7^a,b±5.1	40.3^a,b±6.9	28.4^a±2.5	38.4^a±1.1	31.2^a±0.2	39.7^a±0.3	37.3^a±8.8
	Trans-3-hexenol	1378	1370	S, R, M	58.6^b ±2.2	61.5^b±1.0	57.2^b±6.6	39.3^a±5.8	69^a±0.1	59.6^a±1.3	73.0^a±1.2	68.6^a±15.7
	Benzenemethanol	1880	1834	S, R, M	79.6^a,b±7.0	68.4^a±0.9	83.6^a,b±9.7	86^b ±3.4	77.8^a±3.2	71^a±6.7	97.4^a±8.0	96.9^a±33.5
Terpenes	Limonene	1179	1180	S, R, M	0.4^a±0.0	0.3^a±0.0	0.4^a±0.0	1.1^a±0.6	0.5^a±0.2	0.3^a±0.0	0.4^a±0.0	0.5^a±0.1
	α-Terpinene	1494	−	M	1.1^a±0.1	1.2^a±0.1	1.40^a,b±0.0	1.6^b±0.2	0.8^a±0.0	0.7^a±0.1	1.0^a,b±0.1	1.3^b±0.2
	Linalool	1547	1541	S, R, M	3.3^a±0.7	3^a±0.3	3.6^a±0.5	3.3^a±0.5	2.6^a±0.2	2.6^a±0.0	3.3^a,b±0.1	4.3^b±0.8
	Citronellyl acetate	1657	1666	R, M	1.9^a,b±0.5	2.2 ^b ±0.2	2.1^a,b±0.2	1.4^a±0.2	2.3^b±0.0	2.1^a,b±0.6	2.0^a,b±0.5	1.2^a±0.1
	β–Citronellol	1767	1781	S, R, M	4.8^a±1.2	4^a±0.1	4.5^a±0.6	4.8^a±0.1	3.9^a±0.3	3.3^a±0.2	4.2^a±0.2	4.0^a±0.9
	Isopropyl myristate	2035	2040	R, M	0.3^a±0.3	0.3^a±0.1	0.3^a±0.0	0.1^a±0.0	0.2^a,b±0.0	0.4^c±0.0	0.3^b,c±0.1	0.1^a±0.0
Fatty acids	Hexanoic acid	1859	1789	S, R, M	4821.8^a±643.4	3411.1^a±91.7	4812.9^a±683.2	3689.1^a±527.2	5097.7^a±117.6	4988.2^a±152.8	5125.4^a±1016	6153.9^a±1545.1
	Octanoic acid	2078	1998	S, R, M	2383.2^a±188.4	2247.1^a±39.7	2858.2^b±57.9	3393.4^c±191.2	3240.5^a±194.5	3335.9^a±87.7	3289.6^a±226.0	3731.0^a±1280.8
	Decanoic acid	2289	2279	S, R, M	438^a±4.2	509.5^a,b±47.4	585.6^b±32.2	739.5^c±29.1	679.9^a±4.6	720.3^a±67.0	802^a±16.7	597.3^a±281.9
Others	2,3 Butanedione	937	949	S, R, M	258.7^a±51.6	309.1^a±61.4	280.8^a±59.8	198.1^a±17.8	390.2^c±1.6	400.3^c±21.0	310.5^b±24.2	92.8^a±21.9
	Furfuraldehyde	1459	1449	S, R, M	3^a±0.3	4.5^a,b±0.4	5.6^b±0.1	10.7^c ±1.3	2.9^a±0.4	3.3^a±0.3	3.3^a±0.6	4.0^a±0.9
	γ-Butyrolactone	1613	1595	S, R, M	5644.3^b±400.4	3625.8^a±401.9	5561.9^b±997.3	3579.8^a±486.7	3411.7^a±433	2785.5^a±339.5	3252.8^a±552.7	3074.3^a±807.8
	Methionol	1709	1714	S, R, M	774.9^a±15.4	613.3^a±7.7	804.5^a±217.4	606.2^a±15.7	380.2^a±42.7	324.5^a±97	493.2^a±64.8	381.9^a±201.0
	β-Damascenone*	1809	1752	S, R, M	6^a±0.3	6.5^a,b±0.4	7.4^b±0.3	7.3^b±0.7	6.5^a±0.4	7^a±0.4	8.^a6±0.1	7.9^a±2.2
†Retention index calculated by SPME with an alkane mixture (C5–C30).
‡Retention index reported in the literature from Flavornet database (http://www.webbook.nis.gov/chemistry).
§Identification method: S: identification by comparison with standard compounds; RI: identified by retention index; MS: identified by mass spectra (NIST libraries).
Different superscripts denote statistical differences (p < 0.05) in the values in the same row for each type of wine.

Figure 1 Dendrogram resulting from the application of cluster analysis to the data corresponding to the concentration of volatile compounds determined in the wines of different aging time (1, 2, 3, and 9 months) made with or without the addition of a glutathione enriched IDY preparation (G-IDY-W and Cont-W, respectively).

Table 4  Results from the two-way ANOVA (concentration, judge, concentration × judge) and F-ratios of the sensory terms evaluated by the 10 judges during training in 6 attributes at 2 different concentrations

Attributes	Concentration	Judge	Concentration × judge
Acidity	162.00***	0.22	—
Banana	1699.54***	1.05	1.53
Floral	1077.5***	1.26	1.68
Peach	98.92***	0.20	1.98
Strawberry	2366.46***	2.78*	9.5***
Yeast	116.55***	1.02	2.28
*^,***Denote significance at p < 0.05 and p < 0.001, respectively.

Table 5  Results obtained on the descriptive analysis by the panel of judges (n = 10) of the six sensory attributes evaluated in the control (Cont-W) and GSH-IDY wines (GSH-IDY-W) after 9 months of aging

			Mean
Attributes	F-Ratio	p-Value	Cont-W-9m	GSH-IDY-W-9m
Acidity	0.00	0.9944	7.72	7.71
Banana	3.23	0.0911	4.51	7.16
Floral	0.17	0.6875	7.59	8.24
Peach	4.07	0.0589	7.65	4.81
Strawberry	8.13	0.0116	4.02	7.87
Yeast	11.46	0.0038	4.31	1.91
Judges 1 and 10, not consistent with the whole panel, were excluded from data analysis of strawberry and banana attributes. Attributes in bold were significantly different between wines.

Figure 2 Aroma profiles of Grenache rosé wines in the control wine (Cont-W) and in the wine supplemented with a glutathione enriched IDY preparation (GSH-IDY-W).