# Effect of Production Technique on Pilsner-Style Non-Alcoholic Beer (NAB) Chemistry and Flavor
## 3 Results and Discussion
### Evaluating the Impact of Production Technique on the Volatile Chemistry of the Different NABs
Given the sensory detection threshold of 3-MBT is \(\sim\)4-7 ng/L [37], this is clear analytical evidence that package type can also have an impact on the NAB aroma profile a consumer is going to experience. If this is an undesired characteristic, the implementation of reduced hop acids and/or light-filtering packaging in brown bottles and/or cans has been shown previously to reduce the formation of 3-MBT in alcoholic pilsners [37]. Using Multiple Factor Analysis to Elucidate How Changes in Chemistry Which Are Influenced by Production Technique Result in Changes to NAB Sensory  
Multiple factor analysis (MFA) was performed with the results of the sensory (Table S6) and chemical (Tables 1 and S1-S4) analyses. Based on the active groups used for the analysis, the MFA allowed for distances between each of the NABs to be calculated and visualized by considering each qualitative (i.e., treatments) and quantitative (i.e., sensory, esters, hop volatiles, staling aldehydes, aldehydes/alcohols/esters, sugars, glycerol, ABV, IBU, DMS, 3 MBT, CO2, pH, protein, and dextrins) factor. The MFA observation factor chart of the first two components highlights the impact of production technique as well as the influence of pre- and post-processing decisions amongst the different NAB samples (Figure 2A). The NABs produced primarily though restricted fermentation sit in the bottom right-hand quadrant of the plot. Conversely, except for V2, the beers produced via physical dealcoholization techniques are in the left-hand quadrants (i.e., membrane filtration (M) and vacuum distillation (V)). NABs produced using maltose intolerant yeast as well as those that were dry-hopped sit in the top of the upper right-hand quadrant, while the NABs produced through combined/blended treatments sit both in the bottom of the upper right-hand quadrant as well as the top of the lower right-hand quadrant. To aid in visualization, NABs packaged in green bottles are indicated by green circles and 0.0 NABs are indicated by the inclusion of the text 0.0%. Generally, this supports the finding by [PERSON], [PERSON], and [PERSON] [13] that the choice of production technique is a critical determinative in the resulting flavor profile of NAB. Figure 2: To observe the differences between the different pilisner style NABs, multiple factor analysis (MFA) was performed. **(A)** The observation factor chart showing the NABs in the MFA space. The sample labels are reported in Table 1 and the different treatments are abbreviated as follows: use of Maltose-intolerant yeast (MI), Restricted fermentation (RF), Membrane dealcoholization (M), Vacuum dealcoholization (V), Combined treatments (C). **(B)** The correlation circle map of the MFA with the qualitative (i.e., treatments (turquoise)) and quantitative (i.e., sensory (dark blue), esters (dark gray), hop volatiles (light green), staling aldehydes (dark red), aldehydes/ alcohols/esters (light red), sugars (light orange), glycerol (purple), ABV (pink), IBU (light gray blue), DMS (dark brown), 3 MBT (light brown), CO\({}_{2}\) (dark gray blue), pH (dark green), protein (light gray), and dextrins (black)) factors. During the initial computations, only the quantitative factors were considered. The codes for the factors are defined in Tables 1–3. The correlation circle (Figure 2B) can then be used to observe the relationships amongst the different quantitative and qualitative variables as well as the samples. Variables that are highly correlated are grouped, while variables negatively correlated occur on opposite sides of the plot. For example, worry, sweet, and aftertaste duration occur in the bottom right-hand quadrant, indicating that NABs produced only through restricted fermentation generally had longer aftertastes and were perceived to be the most worry and sweet (Figure 2B and Table S6). These findings are also in agreement with [PERSON], [PERSON], and [PERSON] [13] which showed that products produced by restricted fermentations had strong wort-like aromas and sweet tastes.