USE OF DEFATTED INSECT MEAL AS A BEER CLARIFIER

Beer has played a significant role in the evolution of society, transforming from a craft practice into a key economic sector in industrial biotechnology. A variety of turbidity-removing agents (called clarifiers) are used in the beverage industry, such as agar-agar, chitosan, collagen, and albumin. This study aimed to study the application of edible defatted insect meal (DIM) (Zophobas morio) as a de-clouding agent in commercial Pilsen beer. Beer samples were artificially clouded by adding trub, yeast, and trub + yeast (TL) suspensions. After these additions, the samples were supplemented with either DIM, gelatin, or albumin, all in gel form, and left to stand for 12, 24, and 48 hours. After the exposure time of each clarifier, the samples had their turbidity measured using a portable digital turbidimeter (Akron KR 2000). After each turbidity measurement, the samples were centrifuged and their turbidity was measured again. This experiment was performed with the room temperature and decarbonated beer sample and was repeated with the carbonated beer at refrigerated temperature (5 °C). In the decarbonated and room temperature beer, FDI showed lower clarification performance than gelatin (-85% on average) and albumin (-87.9%) in reducing turbidity caused by trub (-57.5%), yeast (-86.5%), and TL (-87.6%). This was observed at 12, 24, and 48 hours after addition. The centrifugation process led to a reduction in turbidity in the beer with gelatin (-22.3%), but caused an increase in turbidity in the beers with albumin (+15.6%) and FDI (+110.3%). For the use of FDI in carbonated and chilled beer, the behavior was quite different: it proved more effective in reducing turbidity caused by trub (-92.5%), yeast (-87.4%), and TL (-91.3%) than gelatin (average of -70.7%) and albumin (-83.4%). Chilled beer with CO2 without clarifier subjected to centrifugation showed better turbidity reduction (-71.0%) after 48 hours than with the use of any of the clarifiers tested: FDI (-55.6%); albumin (-41.4%), and gelatin (-61.4%). The study concludes that the use of FDI as a clarifier outperforms traditional clarifiers in chilled beer and may be an option for craft brewers who do not have sophisticated equipment such as centrifuges.