Effects of season on the quality of Garfagnina goat milk

Figures & data

Table 1. Descriptive statistics of meteorological measurements.

	Mean ± SD
Item	Spring	Summer
DBT, °C	13.46 ± 4.53	21.87 ± 1.03
WBT, °C	8.70 ± 1.63	14.97 ± 0.34
RH, %	58.7 ± 18.8	73.3 ± 5.0
THI	56.58 ± 4.09	58.44 ± 0.91

SD: standard deviation; DBT: dry bulb temperature; WBT: wet bulb temperature; RH: relative humidity; THI: Temperature Humidity Index.

Table 2. Mean and mean square error of milk quality, cheese making aptitude, milk fatty acids, and physiological parameters in spring and summer.

		Seasons
		Spring (n = 24)	Summer (n = 24)	Mean square error	Significance
Dry Matter, %		11.59	11.58	1.24
Fat, %		2.85	3.30	0.67
Protein, %		2.96	2.76	0.14
Casein, % of protein		81.34	85.17	48.67
Ash, %		0.74	0.73	0.001
Lactose, %		4.52	4.15	0.04	*
r, min		10.26	7.73	2.85	*
k20, min		2.20	1.79	3.05
a30, mm		13.92	9.68	4.74	*
MFG diameter, μm		2.30	2.25	0.27
Number*10^9, mL		5.03	4.21	1.39	*
SG, %		47.92	47.33	181.2
MG, %		48.90	49.74	160.9
LG, %		3.12	1.69	4.78	*
C4:0, % of the total detected FAs		2.26	2.05	0.33
C6:0		2.52	2.23	0.26	*
C8:0		3.15	2.59	0.43	*
C10:0		10.33	8.64	1.39	*
C11:0		0.11	0.07	0.07	*
C12:0		3.85	3.18	0.63	*
C13:0		0.11	0.09	0.04
C14:0		9.00	9.17	1.03
C14:1c9		0.29	0.32	0.07
C15:0		0.97	1.13	0.12	*
C15:1c10		0.22	0.22	0.05
C16:0		24.98	25.91	2.67
C16:1c9		0.46	0.33	0.09	*
C17:0		0.84	0.92	0.18
C17:1c9		0.33	0.24	0.08	*
C18:0		14.54	16.35	3.19	*
C18:1t9		0.17	0.24	0.06	*
C18:1t11		1.26	1.76	0.44	*
C18:1c9		19.15	18.09	2.70
CLAc9,t11		0.35	0.53	0.17	*
C18:2t9,t12		0.42	0.53	0.12	*
C18:2c9,c12		1.86	2.1	0.09
C18:3n3		1.11	1.39	0.04	*
C18:3n6		0.16	0.13	0.22
C20:0		0.21	0.41	0.10	*
C20:1c11		0.06	0.03	0.22	*
C21:0		0.19	0.17	0.18
C20:2c11,c14		0.04	0.02	0.02	*
C20:3 n3		0.04	0.03	0.03	*
C20:3 n6		0.05	0.02	0.09
C20:4n6		0.01	0.01	0.01
C22:0		0.13	0.25	0.08	*
C22:1c13		0.15	0.10	0.05	*
C20:5n3		0.02	0.006	0.04
C23:0		0.10	0.08	0.03
C22:2c13,c16		0.06	0.10	0.03	*
C24:0		0.11	0.15	0.08
C24:1c15		0.02	0.02	0.01
C22:5n3		0.17	0.18	0.04
C22:6n3		0.12	0.13	0.04
SFA		73.40	73.39	2.94
MUFA		22.12	21.36	2.89
PUFA		4.41	5.18	0.48
n6 PUFA/n3 PUFA		1.74	1.66	0.72	*
HR, beat/min		88.9	73.9	13.2	*
RR, mov/min		28.2	32.4	9.70
ST, °C		27.5	28.5	3.14
RT, °C		38.2	38.4	0.33	*

r: clotting time, the time (min) from the addition of rennet to the beginning of coagulation; k20: curd firming time, the time (min) needed until the curd is firm enough to be cut, i.e. the width of the diagram equals 20 mm; a30: curd firmness (mm), measured 30 minutes after the addition of rennet; MFG: milk fat globules; SG: small globules (diameter <2 μm); MG: medium globules (diameter from 2 to 5 μm); LG: large globules (diameter >5 μm); SFA: saturated fatty acids; MUFA: monounsaturated fatty acids; PUFA: polyunsaturated fatty acids; HR: heart rate; RR: respiratory rate; ST: skin temperature; RT: rectal temperature.

* p ≤ .05.

Table 3. Correlations among milk yield, quality, cheese making aptitude, physiological and environmental parameters (n = 48)^a.

Variable	Milk Yield	Fat	Lactose	LG, %	r	a30
DBT	–	–	−0.688**	−0.303*	−0.382**	−0.310*
WBT	–	0.315*	−0.673**	–	–	−0.306*
THI	–	0.345	−0.680**	−0.319*	–	−0.319*
WBGTI	–	0.306*	–	–	−0.281*	−0.310*
ST	–	–	−0.417*	–	–	–
HR	−0.443**	–	–	–	–	–

DBT: dry bulb temperature; WBT: wet bulb temperature; THI: temperature–humidity index; WBGTI: wet bulb globe temperature index; ST: skin temperature; HR: heart rate; LG: large globules (diameter >5 μm); r: clotting time, the time (min) from the addition of rennet to the beginning of coagulation; a30: curd firmness (mm), measured 30 minutes after the addition of rennet.

^a Only significant correlations are reported in the table.

* p ≤ .05; **p ≤ .01.

Table 4. Correlations among milk fatty acid profile, physiological and environmental parameters^a.

Variable	C6:0	C8:0	C10:0	C11:0	C12:0	C13:0	C15:0	C16:1	C17:1c9
WBT	−0.424**	−0.464**	−0.439**	−0.391**	−0.450**	−0.445*	–	−0.617**	−0.539**
DBT	−0.403**	−0.403**	−0.404**	−0.348*	−0.400**	−0.318*	–	−0.540**	−0.492**
RH	0.350*	0.320*	0.291*	–	–	–	–	–	–
THI	−0.421**	−0.450**	−0.429**	−0.371*	−0.428**	−0.428**	0.481**	−0.583**	−0.520**
WBGTI	−0.397**	−0.420**	−0.415**	−0.385**	−0.429**	−0.356*	0.460**	–	–

Table

Variable	C18:0	C18:1t9	C18:1c9	C18:2 n6t	C20:0	C20:1	C20:2	C22:0	C22:1	C22:2
WBT	–	0.491**	0.500**	0.410**	0.656**	0.571**	−0.460**	0.589**	−0.518**	0.526**
DBT	–	0.424**	0.438**	0.369*	0.584**	0.531**	−0.496**	0.518**	−0.528**	0.467**
RH	–	–	–	–	−0.311*	–	0.455**	–	0.388**	–
THI	0.305*	0.462**	0.473**	0.391**	0.627**	0.560**	−0.487**	0.558**	−0.532**	0.502**
WBGTI	–	–	–	0.350*	0.602**	0.527**	−0.472**	0.523*	−0.516**	0.473**

WBT: wet bulb temperature; DBT: dry bulb temperature; RH: relative humidity; THI: temperature humidity index; WBGTI: wet bulb globe temperature index.

^a Only significant correlations are reported in the table.

* p ≤ .05; **p ≤ .01.