Unfilterable Beer Haze Part I: The Investigation of an India Pale Ale Haze

Figures & data

Figure 1. Workflow of haze digestion experiments.

Figure 2. Comparison of pre- and post-digestion values of amyloglucosidase, pepsin, and Ultraflo® Max in control, normal, and high haze beer utilizing EBC units. The dotted line represents the value at which samples were classified as high haze. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate one standard deviation.

Figure 3. Comparison of pre- and post-digestion values of amyloglucosidase, pepsin, and Ultraflo® Max in control, normal and high haze beer measured at a 25° angle compared to the light axis. The dotted line represents the value at which samples were classified as high haze. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate one standard deviation.

Figure 4. Comparison of pre- and post- digestion values of amyloglucosidase, pepsin, and Ultraflo® Max in control, normal, and high haze beer measured at a 90° angle compared to the light axis. The dotted line represents the value at which samples were classified as high haze. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate standard deviation.

Table 1. Averages, standard deviation (S.D.), and p-values obtained from a paired t-test of normal/low haze pre- and post-digestion values (n = 7 brews).

Haze Measurement	Pre-Digestion ^a	S.D.	Post-Digestion ^a	S.D.	P-value
EBC
Amyloglucosidase	1.38	±0.70	0.92	±0.59	<0.0001
Pepsin	1.38	±0.70	0.67	±0.34	<0.0001
Ultraflo® Max	1.38	±0.70	1.09	±0.77	<0.0001
25°
Amyloglucosidase	6.79	±3.18	4.55	±2.44	<0.0001
Pepsin	6.79	±3.18	3.23	±2.52	<0.0001
Ultraflo® Max	6.79	±3.18	4.56	±2.45	<0.0001
90°
Amyloglucosidase	5.37	±2.74	3.59	±2.24	<0.0001
Pepsin	5.37	±2.74	2.69	±1.56	<0.0001
Ultraflo® Max	5.37	±2.74	4.03	±2.68	<0.0001

The p-values determine if significant differences exist between pre- and post-digestion values of amyloglucosidase, pepsin, and Ultraflo®Max at 25° and 90° light angles from which EBC units were calculated.

a Pre- and post-digestion values are average values for the data collected.

Table 2 . Averages, standard deviation (S.D.), and p-values obtained from a paired t-test of high haze pre- and post-digestion values (n = 7 brews).

Haze Measurement	Pre-Digestion ^a	S.D.	Post-Digestion ^a	S.D.	P-value
EBC
Amyloglucosidase	8.69	±2.39	5.59	±2.47	<0.0001
Pepsin	8.69	±2.39	5.00	±1.24	<0.0001
Ultraflo® Max	8.69	±2.39	5.38	±2.41	<0.0001
25°
Amyloglucosidase	35.61	±10.13	2.70	±8.41	<0.0001
Pepsin	35.61	±10.13	8.24	±4.12	<0.0001
Ultraflo® Max	35.61	±10.13	10.39	±8.67	<0.0001
90°
Amyloglucosidase	33.86	±9.21	5.61	±9.51	<0.0001
Pepsin	33.86	±9.21	18.79	±4.76	<0.0001
Ultraflo® Max	33.86	±9.21	21.53	±9.20	<0.0001

The p-values determine if significant differences exist between pre- and post-digestion values of amyloglucosidase, pepsin, and Ultraflo®Max at 25° and 90° light angles from which EBC units were calculated.

a Pre- and post-digestion values are average values for the data collected.

Table 3. Averages, standard deviation (S.D.), and p-values obtained from a paired t-test of control haze pre- and post-digestion values (n = 7 brews).

Haze Measurement	Pre-Digestion ^a	S.D.	Post-Digestion ^a	S.D.	P-value
EBC
Amyloglucosidase	0.21	±0.07	0.12	±0.07	<0.0001
Pepsin	0.21	±0.07	0.10	±0.03	<0.0001
Ultraflo® Max	0.21	±0.07	0.13	±0.07	<0.0001
25°
Amyloglucosidase	0.95	±0.91	0.69	±0.62	0.0015
Pepsin	0.95	±0.91	0.61	±0.52	0.0043
Ultraflo® Max	0.95	±0.91	0.76	±0.72	0.0924
90°
Amyloglucosidase	0.81	±0.26	0.42	±0.24	<0.0001
Pepsin	0.81	±0.26	0.39	±0.12	<0.0001
Ultraflo® Max	0.81	±0.26	0.52	±0.27	<0.0001

The p-values determine if significant differences exist between pre- and post-digestion values of amyloglucosidase, pepsin, and Ultraflo®Max at 25° and 90° light angles from which EBC units were calculated.

a Pre- and post-digestion values are average values for the data collected.

Table 4. ANOVA of the differences in turbidity values, post-digestion, of high, normal, and control beer samples after each enzyme treatment at each angle of incidence measured.

Amyloglucosidase	p-value	Pepsin	p-value	Ultraflo® Max	p-value
EBC		EBC		EBC
High-Control	<0.0001*	High-Control	<0.0001*	High-Control	<0.0001*
Normal-Control	0.464	Normal-Control	0.733	Normal-Control	0.858
Normal-High	<0.0001*	Normal-High	<0.0001*	Normal-High	<0.0001*
25°		25°		25°
High-Control	<0.0001*	High-Control	<0.0001*	High-Control	<0.0001*
Normal-Control	0.464	Normal-Control	0.125	Normal-Control	0.570
Normal-High	<0.0001*	Normal-High	<0.0001*	Normal-High	<0.0001*
90°		90°		90°
High-Control	<0.0001*	High-Control	<0.0001*	High-Control	<0.0001*
Normal-Control	0.734	Normal-Control	0.263	Normal-Control	0.875
Normal-High	<0.0001*	Normal-High	<0.0001*	Normal-High	<0.0001*

* Indicates a significant value

Figure 5. Concentration of total proteins in control, high, and normal haze samples with corresponding p-values calculated by Tukey’s Significant Different Test. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate one standard deviation.

Figure 6. Concentration of total polyphenols in control, high, and normal haze samples with corresponding p-values Tukey’s Significant Different Test. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate one standard deviation.

Figure 7. Concentration of high molecular weight β-glucans in control, high, and normal haze samples with corresponding p-values Tukey’s Significant Different Test. Normal haze samples contained n = 7 brews, high haze samples contained n = 5 brews, and control samples contained n = 2 brews. Error bars indicate one standard deviation.

Table 5. Average values of high molecular weight β-glucan, total polyphenol, and total protein in normal, high, and control samples with corresponding standard deviations (S.D.).

Macromolecule	Normal	S.D.	High	S.D.	Control	S.D.
High Molecular Weight β-glucan (mg/L)	28.18	±14.19	34.73	±3.151	81.97	±7.773
Total Polyphenol (mg/L)	524.40	±35.98	500.23	±41.44	476.87	±1.345
Total Protein (g/L)	5.34	±0.498	5.04	±0.530	4.77	±0.144

Figure 8. Molecular organization of Saccharomyces cerevisiae cell wall adapted from Klis et al. and Lipke and Ovall.^[22,23] The mannoprotein is orange and N-linked or O-linked oligosaccharides are blue. The intercellular β-glucan is in the box and chitin is inside the cell.

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