たまご醤油の調製に関する研究

Abstract

It has been estimated about 500,000 tons of hen's eggs were utilized in food processing annually in Japan. Because of the use of egg yolk has been much higher than that of egg white in the food industry, a large quantity of surplus egg white remained as frozen egg white. Hence, it is worth to develop the use of egg white to normalize the balance for the utilization of egg components. In this report, we demonstrated the preparation of a fermented seasoning sauce in which egg white, whole egg or egg yolk liquid was added to soy sauce koji with large amount of salt. The soy sauce koji is a material that Aspergillus orizae was grown on mixtures of delipidated soy and roasted wheat grain. The salt and protein concentration in each egg component with koji mixture was adjusted to 15.8-16.1% and 12.5-13.0%, respectively, at the start of fermentation. During the fermentation for 6 months, total amino acids % in the supernatant of each mixture was increased to around 10%, with an exception that the value for egg yolk sauce was only 3.6%. The umami taste and flavor of the egg sauce are comparable and characteristic to that of the soy sauce. Moreover, color of the egg sauce is much lighter than that of the soy sauce

卵白液や全卵液を用いた醤油は,従来の醤油麹のみを使用した対照醤油に対し,もろみの量を約2倍に増量しても同等の旨味をもつ醤油が得られた。 卵白液を含む醤油のホルモール態窒素量は約1.0%まで増加した。また,ペプチド鎖平均鎖長は,熟成前は約10で,熟成とともに約2まで分解された。 醗酵熟成中,鶏卵のタンパク質が醤油麹のプロテアーゼにより分解された結果,熟成期間6ヶ月目の卵白を含む醤油のアミノ酸総量は,約10%と対照醤油と同等の値を示した。卵白醤油はアミノ酸総量が高く,旨味や甘味の強い醤油となった。また,熟成期間6ヶ月目の波長550nmにおける吸光度は卵白醤油の色調が顕著に薄かった。以上の結果,卵白を用いたたまご醤油は経済的にも優れ,独特の風味と薄い色調を持ち合わせた,新規の醗酵調味料としての利用が期待できる。