JP4030883B2 - Method for producing milk protein hydrolyzate with reduced odor and milk protein hydrolyzate - Google Patents

Description

【００３８】
［試験例２］
本試験は、メチオナールが低減された乳蛋白質加水分解物の風味を官能的に評価するために行った。
（１）試料の調製
実施例４と同様の方法で製造した乳清蛋白質加水分解物を試験試料２とし、実施例４の多段型薄膜式水蒸気蒸留を行わなかったこと以外は同様の方法で製造した乳蛋白質（乳清蛋白質）加水分解物を対照試料２とし、それぞれ蒸留水で５質量％溶液に調製して、官能試験に供した。
（２）試験方法
２０歳から４０歳までの男女各２０人からなるパネルにより、試験試料２及び対照試料２について次の評価方法に従って風味を官能的に試験した。本発明における風味とは、乳蛋白質加水分解物に特有の不快な臭気が少ないものほど良好と判定し、不快な臭気が多いものほど不良として判定して、それぞれ風味を以下のとおり評価判定を行った。
風味が良好の場合、評価点は２点
どちらとも言えないの場合、評価点は１点
風味が不良の場合、評価点は０点
の３段階に評価し、評価点の平均値を算出し、
１．５点以上：良好
０．５点以上１．５点未満：良好とも不良とも言えない
０．５点未満：不良
の基準により判定した。
（３）試験結果
本試験の結果は表２に示すとおりである。表２は試験試料２及び対照試料２の官能試験の評価点の平均を算出した結果である。その結果、対照試料２の平均評価点は０．８５と算出され、「良好とも不良とも言えない」という評価であったが、試験試料２は平均評価点が１．６と算出され、「良好」の評価結果が得られた。従って、本発明の方法によって製造された乳蛋白質加水分解物は、臭気が低減されたことによって一層風味も改善されたことが明らかとなった。
【表２】

【００３９】
［試験例３］
本試験は、本発明の乳蛋白質加水分解物のメチオナールの含有量を官能的に評価するために行った。
（１）試料の調製
実施例４と同様の方法により、メチオナールの含有量がそれぞれ４００、６００、８００、１０００ｐｐｂとなるように脱臭の程度を調整して製造を行った乳蛋白質（乳清蛋白質）加水分解物を試料とし、それぞれ蒸留水で５質量％溶液に調製して、官能試験に供した。
（２）試験方法
２０歳から４０歳までの男女各２０人からなるパネルにより、各メチオナール濃度の試料について、次の評価方法（評価点算出）に従って臭いを官能的に試験した。
「臭わない」：０点
「乳蛋白質加水分解物製品として気にならない程度の臭い」：１点
「乳蛋白質加水分解物製品として臭いが少々あり、やや不快」：２点
「乳蛋白質加水分解物製品として臭いが強く、不快」：３点
の４段階に評価し、評価点の平均値を算出して「１点未満」を許容できる風味検査基準値として判定した。
（３）試験結果
本試験の結果は表３に示すとおりである。表３は各メチオナール濃度の試料について官能試験の評価点の平均を算出した結果である。その結果、許容できる風味検査基準値が１点未満であったのは、乳蛋白質加水分解物中に含有するメチオナールの含有量が６００ｐｐｂ以下であった。従って、本発明の方法により製造した臭気が低減された乳蛋白質加水分解物は、メチオナールの含有量が６００ｐｐｂ以下であることが判明した。
【００４０】
【表３】

【００４１】
［試験例４］
本試験は、乳蛋白質加水分解物を本発明の多段型薄膜式水蒸気蒸留により脱臭した場合と通常の吸着剤により脱臭した場合でのアミノ酸の回収率を比較するために行った。
（１）試料の調製
実施例１と同様の方法により調製したカゼイン加水分解物（図１記載の多段型薄膜式水蒸気蒸留により脱臭）を試験試料３、実施例１において多段型薄膜式水蒸気蒸留の代わりに、吸着剤（商品名：ＫＳ−３５、味の素ファインテクノ社製）を使用して常法に従って脱臭して調製したカゼイン加水分解物を対照試料３とした。また、実施例１で脱臭（多段型薄膜式水蒸気蒸留）処理を行わなかったカゼイン加水分解物をコントロールとして調製した。尚、試験試料３、対照試料３、及びコントロールはすべて蒸留水で５質量％水溶液となるように溶解して試験に供した。
（２）試験方法
脱臭処理によるアミノ酸の回収率を比較するために、試験試料３及び対照試料３並びにコントロールについて、それぞれアミノ酸組成分析を行い、コントロールに対する試験試料３及び対照試料３の各アミノ酸の回収率（％）を算出した。（３）試験結果
本試験の結果は表４に示すとおりである。表４は、コントロールに対する試験試料３及び対照試料３の各アミノ酸の回収率（％）を算出した結果である。その結果、多段型薄膜式水蒸気蒸留による脱臭を行った試験試料３では、アミノ酸の回収率の低下はほとんど確認されなかったのに対し、吸着剤による脱臭を行った対照試料３では、システイン、及びヒスチジン、並びに塩基性アミノ酸であるアルギニン、リジン、及び芳香族アミノ酸であるフェニルアラニン、トリプトファン、チロシンで、アミノ酸の回収率の低下傾向が確認され、特にトリプトファン（２０．０％）、及びシステイン（６６．７％）で急激に回収率が低下することが明らかとなった。従って、乳蛋白質加水分解物を本発明の多段型薄膜式水蒸気蒸留によって脱臭した場合、従来技術１で公知の吸着剤による脱臭に比してアミノ酸の回収率が良好であることが判明した。
【００４２】
【表４】

【００４３】
［試験例５］
試験例１と同様の方法で調製した試験試料１及び対照試料１について、それぞれの試料中に含まれる三硫化ジメチルを定量し、低減されているかどうか確認するための試験を行った。
メタノールにて０．０１ｐｐｍの濃度に溶解した三硫化ジメチルの標準物質（ＡＣＲＯＳ社製）を用いて、図４に示すクロマトグラフの１６．５分付近のピーク（矢印）が三硫化ジメチルであることを確認し、このピークについて、試験試料１と対照試料１に含まれる三硫化ジメチルを定量した。なお、三硫化ジメチルは、図２の領域Ａに存在する。
その結果を表５に示す。三硫化ジメチルの含有量は、対照試料１では２．４μｇ／試料１ｋｇであったのに対し、試験試料では１．４μｇ／試料１ｋｇとなり、脱臭工程により三硫化ジメチルは４１．７％低減したことが判明した。
【００４４】
【表５】

【００４５】
［試験例６］
試験例３と同様の方法で、乳蛋白質加水分解物中の三硫化ジメチルの含有量を官能的に評価するために以下の試験を行った。
（１）試料の調製
実施例４と同様の方法により、三硫化ジメチルの含有量がそれぞれ２０、４０、６０、８０ｐｐｂとなるように脱臭の程度を調整して製造を行った乳蛋白質（乳清蛋白質）加水分解物を試料とし、それぞれ蒸留水で５質量％溶液に調製して、官能試験に供した。
（２）試験方法
２０歳から４０歳までの男女各２０人からなるパネルにより、各メチオナール濃度の試料について、次の評価方法（評価点算出）に従って臭いを官能的に試験した。
「臭わない」：０点
「乳蛋白質加水分解物製品として気にならない程度の臭い」：１点
「乳蛋白質加水分解物製品として臭いが少々あり、やや不快」：２点
「乳蛋白質加水分解物製品として臭いが強く、不快」：３点
の４段階に評価し、評価点の平均値を算出して「１点未満」を許容できる風味検査基準値として判定した。
（３）試験結果
本試験の結果を表６に示す。表６は各三硫化ジメチル濃度の試料について官能試験の評価点の平均を算出した結果である。その結果、許容できる風味検査基準値が１点未満であったのは、三硫化ジメチルの含有量が４０ｐｐｂ以下の乳蛋白質加水分解物であった。従って、本発明の方法により製造した臭気が低減された乳蛋白質加水分解物は、三硫化ジメチルの含有量が４０ｐｐｂ以下であることが判明した。
【００４６】
【表６】

【００４７】
【実施例】
次に実施例を示して本発明を更に詳細に説明するが、本発明は以下の実施例に限定されるものではない。
【００４８】
〔実施例１〕
乳酸カゼイン（蛋白質含有量８５％。ユニーレ・フランス社製）１ｋｇを精製水１０ｋｇに溶解し、水酸化ナトリウム（日本曹達社製）１３ｇ及び水酸化カリウム（日本曹達社製）３３ｇを添加して、ｐＨを９．３に調整し、バチルス属細菌由来の中性プロテアーゼ（商品名：プロテアーゼＮ。天野エンザイム社製）１６８万活性単位（蛋白質１ｇ当たり２，０００活性単位）、バチルス属細菌由来のアルカリ性プロテアーゼ（商品名：ビオプラーゼｓｐ−２０。長瀬生化学工業社製）１００．８万活性単位（蛋白質１ｇ当たり１，２００活性単位）、及びトリプシン（商品名：トリプシンＶ。日本バイオコン社製）５８８万活性単位（蛋白質１ｇ当たり７，０００活性単位）を添加し、５０℃で加水分解し、酵素反応を分解率によりモニターし、分解率が２４％及びアミノ酸遊離率が４．３％に達した時点で、１３０℃で２秒間加熱して酵素を失活させた。この加水分解液を、分画分子量６，０００の限外濾過膜モジュール（商品名：ＳＩＰ１０３０。旭化成社製）により限外濾過し、次いで膜透過画分を濃縮して、噴霧乾燥し、粉末状のカゼイン加水分解物約７．５ｋｇを得た。
得られたカゼイン加水分解物５ｋｇを精製水９５ｋｇに溶解し、溶液濃度５％、温度５０℃、処理流量５０ｌ／ｈ、気液接触装置の回転体の回転数を４０ｓ^−１（２４０ｒｐｍ）、接触塔下部からの蒸気と熱風を各々５ｋｇ／ｈ、１ｍ^３／ｈの割合で吹き込み、真空圧力−７０ｋＰａでカゼイン加水分解液の臭気成分を蒸気に移動させて水蒸気蒸留処理した。
以上の方法により製造したカゼイン加水分解物処理溶液は、前記試験方法で試験した結果、メチオナールの含有量は２０ｐｐｂ、かつ三硫化ジメチルの含有量は１．４ｐｐｂであり、食品、化粧品等にそのまま使用可能な優れたものであった。
【００４９】
〔実施例２〕
市販の乳清蛋白質濃縮物（蛋白質含有量７５％。ワーナンブール・チーズ・アンド・バター社製）１ｋｇを精製水９ｋｇに溶解し水酸化ナトリウム（日本曹達社製）５．５ｇを添加してｐＨを７．５に調整し、パパイン（商品名：パパイン３００。日本バイオコン社製）３８２．５万活性単位（蛋白質１ｇ当たり５，１００活性単位）、トリプシン（商品名：ＰＴＮ６．０Ｓ。ノボザイムズ・ジャパン社製）１１２．５万活性単位（蛋白質１ｇ当たり１，５００活性単位）、及び乳酸菌ラクトバチルス・ヘルベチクス由来のプロテアーゼ１３．５万活性単位（蛋白質１ｇ当たり１８０活性単位）を添加し、５０℃で加水分解し、酵素反応を分解率によりモニターし、分解率が１５．８％及びアミノ酸遊離率が６．１％に達した時点で、１３０℃で２秒間加熱して酵素を失活させ、１０℃に冷却した。この加水分解液を、分画分子量１０，０００の限外濾過膜モジュール（商品名：ＳＬＰ−１０５３。旭化成社製）により限外濾過し、次いで膜透過画分を溶液濃度５％、温度５０℃、処理流量５０ｌ／ｈ、気液接触装置の回転体の回転数を３５ｓ^−１（２１０ｒｐｍ）、接触塔下部からの蒸気と熱風を各々７ｋｇ／ｈ、０．５ｍ^３／ｈの割合で吹き込み、真空圧力−６０ｋＰａで乳清蛋白質加水分解液の臭気成分を蒸気に移動させて水蒸気蒸留処理した。更に濃縮して、噴霧乾燥し、粉末状の乳清蛋白質加水分解物約０．７５ｋｇを得た。
得られた乳清蛋白質加水分解物は、前記試験方法で試験した結果、分解率が１５．８％、アミノ酸遊離率が６．１％、メチオナールの含有量が３５０ｐｐｂ、及び三硫化ジメチルの含有量が２３ｐｐｂであり、食品、化粧品等にそのまま使用可能な優れたものであった。
【００５０】
〔実施例３〕
乳酸カゼイン（蛋白質含有量８５％。ニュージーランド・ミルク・プロダクツ製）１ｋｇを精製水８ｋｇに溶解し、水酸化ナトリウム（日本曹達社製）２５ｇを添加してｐＨを７．０に調整し、パンクレアチン（商品名：パンクレアチンＦ。天野エンザイム社製）４２．５万活性単位（蛋白質１ｇ当たり５００活性単位）、及び乳酸菌ラクトバチルス・ヘルベチクス由来のプロテアーゼ１２０万活性単位（蛋白質１ｇ当たり１，４１０活性単位）を添加し、５０℃で加水分解し、酵素反応を分解率によりモニターし、分解率が３５％及びアミノ酸遊離率が４０％に達した時点で、１３０℃で２秒間加熱して酵素を失活させ、１０℃に冷却した。この加水分解液を珪藻土濾過により清澄化し、清澄化液を濃縮した。更に該清澄化液を噴霧乾燥して、粉末状のカゼイン加水分解物約０．８２ｋｇを得た。得られたカゼイン加水分解物０．８ｋｇを精製水１５．２ｋｇに溶解し、溶液濃度５％、温度５０ ℃、処理流量３５ｌ／ｈ、気液接触装置の回転体の回転数を４５ｓ^−１（２７０ｒｐｍ）、接触塔下部からの蒸気と熱風を各々３ｋｇ／ｈ、０．５ｍ^３／ｈの割合で吹き込み、真空圧力−６０ｋＰａでカゼイン加水分解液の臭気成分を蒸気に移動させて水蒸気蒸留処理した。
以上の方法により製造したカゼイン加水分解物処理溶液は、前記試験方法で試験した結果、メチオナールの含有量は１５ｐｐｂ、かつ三硫化ジメチルの含有量は１．０ｐｐｂであり、食品、化粧品等にそのまま使用可能な優れたものであった。
【００５１】
〔実施例４〕
市販の乳清蛋白質濃縮物（蛋白質含量７５％。ミライ社製）１０ｋｇを精製水９０ｋｇに溶解し、水酸化ナトリウム（三栄源エフ・エフ・アイ社製）５５ｇを添加してｐＨを７．５に調整した。次いで、パパイン（商品名：パパイン３００。日本バイオコン社製）４８８０万活性単位（蛋白質１ｇ当たり６，５００活性単位）、及びトリプシン（商品名：ＰＴＮ６．０Ｓ。ノボザイムズ・ジャパン社製）４６９０万活性単位（蛋白質１ｇ当たり６，２５０活性単位）を添加して、５０℃で加水分解し、酵素反応を分解率によりモニターし、分解率が１３．７％に達した時点で、１３０℃で２秒間加熱して酵素を失活させ、１０℃に冷却した。
この加水分解液を分画分子量１０，０００の限外濾過膜モジュール（商品名：ＳＬＰ−１０５３。旭化成社製）により処理し、膜透過画分を濃縮して噴霧乾燥し、粉末状の乳清蛋白質加水分解物約７．３ｋｇを得た。
得られた乳清蛋白質加水分解物６ｋｇを精製水１１４ｋｇに溶解し、溶液濃度５％、温度５０℃、処理流量７０ｌ／ｈ、気液接触装置の回転体の回転数を４５ｓ^−１（２７０ｒｐｍ）、接触塔下部からの蒸気と熱風を各々７ｋｇ／ｈ、１ｍ^３／ｈの割合で吹き込み、真空圧力−６５ｋＰａで乳清蛋白質加水分解液の臭気成分を蒸気に移動させて水蒸気蒸留処理した。
以上の方法により製造した乳清蛋白質加水分解物は、前記試験方法で試験した結果、メチオナールの含有量は５００ｐｐｂ、かつ三硫化ジメチルの含有量は３５ｐｐｂであり、食品、化粧品等にそのまま使用可能な優れたものであった。
【００５２】
〔実施例５〕
乳清蛋白質濃縮物（蛋白質含有量７５％。ミライ社製）１０ｋｇを精製水７０ｋｇに溶解し、バチルス属細菌由来の中性プロテアーゼ（商品名：プロテアーゼＮ。天野エンザイム社製）１，８００万活性単位（蛋白質１ｇ当たり２，４００活性単位）、及び乳酸菌ラクトバチルス・ヘルベチクス由来のプロテアーゼ６８万活性単位（蛋白質１ｇ当たり９０活性単位）を添加し、５０℃で加水分解し、酵素反応を分解率によりモニターし、分解率が２３％及びアミノ酸遊離率が１１％に達した時点で、８５℃で６分間加熱して酵素を失活させ、１０℃に冷却した。この加水分解液を、分画分子量３，０００の限外濾過膜モジュール（商品名：ＳＥＰ−３０１０。旭化成社製）により限外濾過し、得られた乳清蛋白質加水分解物を含有する溶液を濃縮して、噴霧乾燥し、粉末状の乳清蛋白質加水分解物約７．４ｋｇを得た。
得られた乳清蛋白質加水分解物６ｋｇを精製水１１４ｋｇに溶解し、溶液濃度５％、温度５０℃、処理流量１００ｌ／ｈ、気液接触装置の回転体の回転数を４０ｓ^−１（２４０ｒｐｍ）、接触塔下部からの蒸気と熱風の各々１０ｋｇ／ｈ、２ｍ^３／ｈの割合で吹き込み、真空圧力−６０ｋＰａで乳清蛋白質加水分解液の臭気成分を蒸気に移動させて水蒸気蒸留処理した。
以上の方法により製造した乳清蛋白質加水分解物は、前記試験方法で試験した結果、メチオナールの含有量は４５０ｐｐｂ、かつ三硫化ジメチルの含有量は３０ｐｐｂであり、食品、化粧品等にそのまま使用可能な優れたものであった。
【００５３】
【発明の効果】
以上詳記したとおり、本発明は臭気が著しく低減された乳蛋白質加水分解物の製造方法、及び乳蛋白質加水分解物に関するものであり、本発明により奏される効果は次のとおりである。
（１）本発明の方法により、広範な用途に適用することが可能な臭気が低減された乳蛋白質加水分解物を製造することができる。
（２）本発明の乳蛋白質加水分解物は、臭気が低減されていることから、種々の食品及び化粧品等の素材として好適に使用することができる。
【図面の簡単な説明】
【図１】 本発明の好ましい実施態様で用いられる多段型薄膜式気液接触装置を示す概略図である。
【図２】 参考試験の乳蛋白質加水分解物のＧＣ−ＭＳクロマトグラムである。
【図３】 試験例１の試験試料１及び対照試料１のガスクロマトグラムである。
【図４】 試験例５の試験試料１及び対照試料１のガスクロマトグラムである。
【符号の説明】
１…多段型気液接触装置、１Ａ…接触塔、２Ａ…被処理液の入口、４Ａ…気体の入口、６Ａ…被処理液の出口、８Ａ…気体の出口、９…回転軸、１０…回転体、１３…湾曲畝部、２０…受け皿[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a milk protein hydrolyzate with reduced odor and a milk protein hydrolyzate useful as a food material or cosmetic material.
[0002]
[Prior art and problems to be solved by the invention]
Mixtures of peptides and free amino acids obtained by hydrolyzing proteins, that is, protein hydrolysates have various advantages compared to single proteins and amino acid mixtures. It is attracting attention from various directions.
For example, dipeptides and tripeptides are absorbed by a route different from that of amino acids, and the absorption rate is faster or the amount of absorption of individual amino acids varies compared to the mixture of constituent amino acids that make up those peptides. It has been made clear that there is no such thing.
In addition, since the protein contained in food is a heterologous protein for humans, it has antigenicity as it is, and may exhibit allergic symptoms when absorbed in the body in an indigestible state. is there. On the other hand, protein hydrolyzate is less likely to exhibit allergic symptoms because its antigenicity is reduced or eliminated. For this reason, foods containing protein hydrolysates are gradually increasing as foods that prevent allergic symptoms due to proteins in foods and enable sufficient nutrition.
Furthermore, protein hydrolysates are useful as cosmetics and skin external preparations because of their functional properties, and are also used in this field (for example, Patent Documents 1 and 2).
[0003]
However, protein hydrolysates may produce unpleasant odors by various treatments.
In particular, when milk protein is used as a raw material protein, an unpleasant odor peculiar to a milk protein hydrolyzate, such as a raw milk odor, a peptide peculiar odor, and a casein odor, may be generated by heat treatment or the like. If such milk protein hydrolyzate having an unpleasant odor is used as it is as a raw material for food or cosmetics, the unpleasant odor will be transferred to those products. This is a major limitation when using milk protein hydrolyzate for food or cosmetics.
On the other hand, for example, Patent Document 3 discloses a hypoallergenic peptide-containing composition comprising a peptide and a free amino acid having a specific composition obtained by degrading casein with a proteolytic enzyme. Here, aromatic amino acids which are odor components and bitter components are reduced, and specific examples of odor components include free fatty acids such as butyric acid. However, in such a peptide-containing composition, the unpleasant odor peculiar to milk protein hydrolyzate has not been sufficiently reduced.
Therefore, a method capable of producing a milk protein hydrolyzate in which the unpleasant odor peculiar to the milk protein hydrolyzate is sufficiently reduced is desired.
[0004]
By the way, a method that uses an adsorbent such as activated carbon or anion exchange resin has been widely used for deodorization treatment in the fields of food industry, chemical industry, and the like. A mixture of a peptide obtained by hydrolysis and a free amino acid is deodorized with an adsorbent (hereinafter referred to as Prior Art 1). For example, in patent document 3 mentioned above, odor components, such as a free fatty acid, are removed using adsorption agents, such as anionic adsorption resin.
Patent Document 4 discloses a protein hydrolyzate using a nanofiltration membrane, a membrane-impermeable fraction mainly composed of peptides, and a membrane-permeable image mainly composed of free amino acids and odor-causing substances. A method for producing a protein hydrolyzate with reduced odor, characterized in that the membrane permeation fraction is deodorized and mixed with the membrane non-permeation fraction (hereinafter, It is called prior art 2.) This method has no loss of useful peptides, high recovery rate of protein hydrolyzate, no unpleasant odor due to reheating, and protein hydrolyzate with reduced odor can be obtained. Excellent in terms.
[0005]
However, each of these conventional techniques has drawbacks and limitations.
For example, when the method of Prior Art 1 is used, there is a problem that not only an unpleasant odor, but also certain amino acids and some useful peptides are simultaneously reduced. For example, in Patent Document 3 described above, the amount of aromatic amino acid is reduced. For this reason, the recovery rate of the produced protein hydrolyzate is reduced, resulting in a disadvantage that nutritional and functional loss is caused.
Moreover, when the method of the prior art 2 is used, there is a restriction that the protein is hydrolyzed in a range where the percentage of the content of free tyrosine and phenylalanine relative to the total tyrosine and phenylalanine content of the raw protein is 75% or less. Therefore, for example, there has been a problem that antigenicity cannot be sufficiently reduced or completely eliminated. In addition, the nanofiltration membrane and an apparatus for performing membrane separation are necessary, and a mixing operation is necessary again after the separation, and the process is complicated.
[0006]
Further, Patent Documents 5 and 6 disclose that animal skin and egg white are characterized by enzymatic hydrolysis of animal skin and egg white and egg white albumin in the presence of hexose or pentose, followed by steam distillation of the solution. Alternatively, a method for producing a seasoning having a meat flavor from egg white albumin is disclosed.
However, these methods use steam distillation to reduce the off-flavor peculiar to the enzyme hydrolyzate of animal skin, and at the same time, the three of animal skin hydrolyzate, hexose or pentose and egg white or egg white albumin hydrolyzate. Since it is a method of obtaining an aroma component having a meat flavor from an ingredient, it is intended for a very limited hydrolyzate derived from animal skin, etc., and the only odor component is ammonia peculiar to these hydrolysates. Not considered.
[0007]
[Patent Document 1]
JP-A-4-26604
[Patent Document 2]
JP-A-4-26605
[Patent Document 3]
Japanese Patent No. 3233779
[Patent Document 4]
JP-A-10-271958
[Patent Document 5]
Japanese Patent Laid-Open No. 52-10457
[Patent Document 6]
JP-A-52-99265
[0008]
Therefore, the object of the present invention is to provide a milk protein hydrolyzate with reduced odor that is useful as a food material or cosmetic material, and the odor can be efficiently produced in a simple process without losing useful peptides. It is to provide a method for producing reduced milk protein hydrolysates.
[0009]
[Means for Solving the Problems]
As a result of intensive studies on odor components peculiar to milk protein hydrolysates, the present inventors have found that methional contained in milk protein hydrolyzate obtained by hydrolyzing milk protein with protease, three Specific substances such as dimethyl sulfide are odorous substances that cause unpleasant odor of milk protein hydrolysates, and milk protein hydrolysis with reduced odor by reducing this specific odorous substance It was found that the product can be manufactured, and the present invention was completed.
[0010]
  That is, the first invention of the present invention that solves the above problems includes a hydrolysis step of hydrolyzing milk protein with a protease to obtain a milk protein hydrolyzate, and an odor contained in the milk protein hydrolyzate. SubstanceBy steam distillation using a multi-stage thin film gas-liquid contactorA method for producing a milk protein hydrolyzate having reduced odor, characterized by comprising a deodorizing step to reduce the odor, and the following (1) to (3) Are preferred embodiments.
  (1) The odor substance reduced by the deodorization step is methional or dimethyl trisulfide.
  (2) In the deodorization step, the content of methional is calculated based on the total mass of the milk protein hydrolyzate.15ppb or more600 ppb or less, or the content of the dimethyl trisulfide is adjusted to the total mass of the milk protein hydrolyzate.1.0ppb or more40 ppb or less.
  (3) In the hydrolysis step, after obtaining a hydrolyzate containing a milk protein hydrolyzate, the deodorization step is performed without drying..
A first aspect of the present invention for solving the above-mentioned problems.twoThe invention ofProduced by the method for producing a milk protein hydrolyzate,Thional content is15ppb or moreIt is a milk protein hydrolyzate characterized by being 600 ppb or less.
  A first aspect of the present invention for solving the above-mentioned problems.threeThe invention ofProduced by the method for producing the milk protein hydrolyzate,The content of dimethyl trisulfide is1.0ppb or moreIt is a milk protein hydrolyzate characterized by being 40 ppb or less.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail. In the present invention, the content ppb is in terms of solid content (per total mass of milk protein hydrolyzate).
In the present invention, odor means an unpleasant unpleasant odor among fragrance components contained in milk protein hydrolysis (for example, raw peptide odor, casein odor, sulfur odor, spoiled odor, burnt odor, mold odor, etc.) To do.
And reduction of odor means reducing such an unpleasant fragrance, and means that a preferable fragrance is maintained without being reduced.
[0012]
Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following preferred embodiments, and can be freely modified within the scope of the present invention.
[0013]
The method for producing a milk protein hydrolyzate with reduced odor according to the present invention (hereinafter sometimes referred to as the method of the present invention) includes a hydrolysis step of hydrolyzing milk protein with a protease to obtain a milk protein hydrolyzate. And a deodorizing step for reducing odorous substances contained in the milk protein hydrolyzate.
[0014]
The raw material of the milk protein hydrolyzate produced by the method of the present invention can be any material as long as it has a milk protein as a main component, such as lactate casein, casein hydrochloride, casein sodium, and casein calcium. And commercially available whey proteins such as whey protein concentrate (WPC) and whey protein isolate (WPI), total milk protein, and the like. It is also possible to use milk protein purified from milk, skim milk, whole milk powder and skim milk by a conventional method. Furthermore, purified milk proteins contained in milk, such as lactoferrin, lactoperoxidase, serum albumin, immunoglobulin, etc. may be used as a raw material for the milk protein hydrolyzate used in the method of the present invention. Is possible.
[0015]
In the hydrolysis step, first, the raw milk protein as described above is dispersed and dissolved in water or hot water. The concentration of the milk protein in the solution is not particularly limited, but it is usually desirable from the viewpoint of efficiency and operability to set a concentration range of about 5 to 15% by mass in terms of protein.
The solution containing the milk protein is preferably sterilized by heating at 70 to 90 ° C. for about 15 seconds to 30 minutes from the viewpoint of preventing deterioration due to contamination with various bacteria.
[0016]
Next, it is desirable to add an acid agent or an alkali agent to the solution containing the milk protein to adjust the pH of the solution to or near the optimum pH of the protease to be used. The acid agent or alkali agent used in this case may be any one as long as it is acceptable for food. Specifically, examples of the acid agent include citric acid, acetic acid, malic acid, gluconic acid and the like. Examples of the organic acid, inorganic acid such as hydrochloric acid, and alkali agent include sodium hydroxide, potassium hydroxide, potassium carbonate and the like.
[0017]
Next, one or more proteases are added to the solution containing the milk protein. The protease to be used is not particularly limited, and animal-derived, plant-derived, or microbial-derived proteases can be used, and commercially available products may be used. May be.
[0018]
Examples of animal-derived proteases include pepsin, pancreatin, trypsin, chymotrypsin, etc., and commercially available products include pepsin (manufactured by Wolfgang Mühlbauer), pancreatin F (manufactured by Amano Enzyme), PTN 6.0S (Novozymes Japan). And chymotrypsin (manufactured by Nippon Biocon).
Examples of plant-derived proteases include papain and bromelain, and examples of commercially available products include papain 300 (manufactured by Nippon Biocon), bromelain F (manufactured by Amano Enzyme), and the like.
Examples of proteases derived from microorganisms include proteases derived from Bacillus bacteria, proteases derived from lactic acid bacteria, proteases derived from Aspergillus fungi, proteases derived from Streptomyces spp., Proteases derived from Saccharomyces yeasts, etc. Examples include protease N (manufactured by Amano Enzyme), alcalase 2.4L (manufactured by Novozymes Japan), bioprase sp-20 (manufactured by Nagase Seikagaku Corporation), protease A (manufactured by Amano Enzyme), and the like.
Here, a protease derived from a lactic acid bacterium can be produced, for example, by the method described in the section of “(3) Enzyme to be used”, column 6, line 4 of JP-B-54-36235. That is, lactic acid bacteria (including bifidobacteria) are cultured by a known method (for example, the method described in Japanese Patent Publication No. 48-43878), and the obtained culture solution is centrifuged to collect lactic acid bacteria cells and put them in sterile water. The operation of suspending the microbial cells and centrifuging to collect the lactic acid bacterium cells is repeated twice, the microbial cells are washed, suspended in sterilized water at a concentration of 20%, and a microbial cell disrupter [for example, KDL Type: Manufactured by Willy Bachnfen Engineering. ] Is crushed and freeze-dried to obtain protease powder derived from lactic acid bacteria. Examples of lactic acid bacteria include Bifidobacterium longum, Bifidobacterium infantis, and Bifidobacterium breve, which are lactic acid bacteria belonging to the genus Bifidobacterium. Lactobacillus helveticus Lactobacillus helveticus, Lactobacillus casei, Lactobacillus bulgaricus, Lactobacillus acidophilus Lactobacillus acidophilus, etc. Streptococcus thermophillus (Streptococcus thermophillus) etc. can be illustrated, respectively.
[0019]
These proteases are dispersed in cold water at 4 to 10 ° C. and dissolved before use. The concentration of the lysate is not particularly limited, but it is usually desirable to use it as an enzyme concentration of about 3 to 10% from the viewpoint of efficiency and operability.
The amount of protease used varies depending on the substrate concentration, enzyme titer, reaction temperature, and reaction time, but is generally added at a rate of 20 to 20,000 active units per gram of milk protein.
The definition of the activity unit of protease activity is that a protease is allowed to act on casein (trade name: Hammerstein, manufactured by Merck), and an allyl amino acid corresponding to 1 μg of tyrosine per minute at 30 ° C. is exhibited by a forin reagent. The enzyme activity titer showing a color reaction is defined as 1 activity unit.
In particular, for protease activity derived from lactic acid bacteria, leucylparanitroanilide (manufactured by Kokusan Chemical Co., Ltd.) is dissolved in 0.1 M phosphate buffer (pH 7) to prepare a 2 mM substrate solution. Add 1 ml of substrate solution to 1 ml of enzyme solution and react at 37 ° C. for 5 minutes, then add 2 ml of 30% acetic acid solution to stop the reaction, filter the reaction solution with a membrane filter, and measure the absorbance at 410 nm wavelength. To do. The amount of enzyme required to decompose 1 μmol of leucylparanitroanilide per minute was defined as one activity unit, and the activity unit of protease derived from lactic acid bacteria was determined by the following formula.
Protease (exo-type) activity unit = 20 × (P / Q)
Where P is the absorbance of the sample at a wavelength of 410 nm, and Q is the absorbance of 0.25 mM paranitroaniline at a wavelength of 410 nm.
[0020]
When a plurality of proteases are added to the sample solution, it is desirable to dissolve and add the proteases one by one, but the order of addition is not particularly limited.
[0021]
The temperature of the enzyme reaction is not particularly limited and is selected from a range that can be put to practical use including the optimum temperature range in which the enzyme action is manifested, and is usually selected from the range of 30 to 60 ° C.
In addition to the reaction temperature, the reaction conditions such as the enzymatic hydrolysis reaction time are the conditions for obtaining a degradation product having the desired physicochemical properties (eg, degradation rate, molecular weight distribution, residual antigenicity, amino acid release rate, etc.). Set as appropriate.
[0022]
Further, the degree of hydrolysis and / or free amino acid can be appropriately monitored as necessary.
The degree of hydrolysis (hydrolysis rate) can be monitored, for example, by measuring the rate of protein degradation over time. The method for measuring the hydrolysis rate is specifically exemplified by formol titration (edited by Jens Aldler-Nissen, “ENZYMIC HYDROLYSIS OF FOOD PROTEINS”, published by ELSEVIER APPLIED SCIENCE PUBLISHERS LTD, pages 12-13, 1986). be able to.
The degree of free amino acid is determined by measuring the amount of specific amino acid released in the decomposition solution over time, starting hydrolysis. Specifically, HPLC, biotech analyzer (Asahi Kasei Kogyo Co., Ltd.), perfusion chromatography (Perceptive Biosystems Co., Ltd. BioCAD) and the like are performed by a known method (for example, JP-A-8-112004). It can be monitored by measuring the specific amino acids used and released over time. Since the amount of amino acid to be liberated varies depending on the type of raw material protein and enzyme used, it is desirable to select the amino acid that is most likely to be liberated as the specific amino acid.
[0023]
When the degree of hydrolysis and / or free amino acid reaches a desired level, it is desirable to immediately deactivate or reduce the enzyme in the reaction solution to stop the hydrolysis.
The enzyme reaction can be stopped by heat deactivation treatment by a conventional method.
The heating temperature and holding time of the heat deactivation treatment can be set as appropriate under conditions that allow sufficient deactivation in consideration of the thermal stability of the enzyme used. For example, the heating temperature and holding time can be set within a temperature range of 80 to 130 ° C. for 30 minutes. It can be performed with a holding time of ˜2 seconds.
[0024]
The hydrolysis deactivation liquid obtained by inactivating the enzyme as described above is subjected to separation and purification treatment as necessary to purify the milk protein hydrolyzate contained in the hydrolysis deactivation liquid. be able to. By performing the separation and purification treatment, it is possible to remove insoluble matters such as precipitates, desalting, clarification of the solution, fractionation by molecular weight, reduction of bitterness, and the like.
Examples of the separation and purification treatment include diatomaceous earth filtration treatment, precision membrane treatment, ultrafiltration membrane treatment, nanofiltration membrane treatment, chromatographic treatment, and adsorption resin treatment. A known apparatus can be used for these processes.
[0025]
Next, the deodorizing process will be described.
In a preferred embodiment of the present invention, the odor substance to be reduced in the deodorization step is methional (also called 3- (methylthio) propionaldehyde) or dimethyl trisulfide.
Methional is a substance generated from methionine by heat treatment or the like, and is generally known as a diffusible onion or meat-like aroma. Methional alone is currently used as a flavoring ingredient for cheese, meat products, fruit and soups, but it has been unpleasant for milk protein hydrolysates. There are no reports of odors. Dimethyl trisulfide is a substance present in hops and cabbages, and is generally known as a strong and fresh onion-like fragrance. Dimethyl trisulfide is used alone as a flavor for meat and the like. For example, when 10 ppb is added to meat flavor, roast chicken scent is produced. Also, about 1 ppm is added to baked goods. To date, dimethyl trisulfide, like methional, has not been reported to cause unpleasant odor of milk protein hydrolysates.
[0026]
Any known deodorizing method can be used as a method for reducing odorous substances in the deodorizing step. As described above, methods for reducing odorous substances in general protein hydrolysates include methods using an adsorbent such as activated carbon, methods using a nanofiltration membrane, and methods using steam distillation. However, steam distillation is preferably used. This is because deodorization by steam distillation reduces loss of milk protein hydrolyzate and improves the recovery rate.
[0027]
Steam distillation means an operation in which steam is blown into a liquid containing an odorous substance to be deodorized and the odorous substance is distilled together with the steam.
In a preferred embodiment of the present invention, the steam distillation is performed using a multi-stage thin film gas-liquid contact device.
FIG. 1 shows a multistage gas-liquid contact device 1 that is preferably used in this embodiment. This multistage gas-liquid contact device 1 is provided with an inlet 2A for the liquid 2 to be processed such as a hydrolysis deactivation liquid and an outlet 8A for the gas 8 on the top side, and an outlet 6A and a gas 4 for the liquid 6 to be processed on the bottom side. The contact tower 1A provided with the inlet 4A, the rotary shaft 9 inserted in the contact tower 1A in the vertical direction, and the rotary shaft 9 are arranged in multiple stages at intervals, and the liquid to be treated is centrifuged. The apparatus includes a rotating body 10 that is thinned by force and discharged from the outer periphery, and a tray 20 that receives a liquid to be processed discharged from the upper rotating body and guides the liquid to the center of the lower rotating body. In this multistage gas-liquid contact device 1, the rotating body 10 is provided with a curved collar 13 over which the liquid to be processed that is thinned and flows from the center of the rotating body toward the outer peripheral direction gets over.
[0028]
In this multistage gas-liquid contact device 1, for example, while rotating the rotating body 10 installed in the sealed contact tower 1A in a fixed direction, the liquid 2 to be treated flows down from the top of the contact tower 1A, and rotates. The film is thinned on the body 10 and discharged from the outer periphery of the rotating body 10, received by the receiving tray 20, and sequentially flowing down to the rotating body 10 below and flowing down from the top to the bottom of the contact tower 1A. By contacting with steam or hot air moving from the bottom to the top of the contact tower 1A, the odor component of the liquid to be treated can be recovered by moving to the steam or hot air.
Since the rotating body 10 is provided with a curved flange portion 13, when the liquid to be treated is flowed from the center of the rotating body to the outer peripheral direction, the liquid to be processed gets over the curved flange portion 13 and is efficiently surrounded. Since it contacts with gas, the odorous substance in a to-be-processed liquid can be reduced efficiently.
At this time, the temperature of the liquid to be treated, the amount of liquid supply, the number of rotations of the rotating body of the gas-liquid contact device, the amount of steam and hot air blown, and the like can be set as appropriate.
[0029]
The solution containing the milk protein hydrolyzate obtained after steam distillation using the multistage thin-film gas-liquid contact device 1 or the like can be used as it is by adding it to foods and cosmetics, and if necessary It can also be concentrated and used as a concentrate. Furthermore, this concentrated liquid can be dried and used as a powder.
[0030]
The hydrolyzed milk protein hydrolysis-inactivated liquid or the separated and purified liquid after the hydrolysis treatment may be steam-distilled as it is without performing an extra step such as drying, or once concentrated and dried to form a powder. Then, it can be dissolved again in distilled water or the like and reduced to an aqueous solution to obtain a milk protein hydrolyzed solution, followed by steam distillation to remove odor. Once the method of distillation after drying is adopted, it is possible to reduce the milk protein hydrolyzate to an aqueous solution by the required amount when necessary, and steam-distill to produce a product as a material with reduced odor. is there.
[0031]
The milk protein hydrolyzate produced as described above has a reduced characteristic unpleasant odor and is suitable for use in foods and cosmetics.
[0032]
Next, the second invention of the present invention will be described. The second invention of the present invention is a milk protein hydrolyzate characterized in that unpleasant odor substances are reduced. Unpleasant odor substances include in particular methional or dimethyl trisulfide.
That is, the third invention of the present invention is a milk protein hydrolyzate characterized in that the content of methional is 600 ppb or less.
The fourth invention of the present invention is a milk protein hydrolyzate characterized in that the content of dimethyl trisulfide is 40 ppb or less.
[0033]
The milk protein hydrolyzate can be produced, for example, by hydrolyzing the milk protein with an acid, alkali, enzyme or the like, and deodorizing the obtained hydrolyzate using a conventional method. It manufactures using the manufacturing method of the milk protein hydrolyzate with which the odor was reduced as mentioned above.
[0034]
In a preferred embodiment, the milk protein hydrolyzate of the present invention has a conventional milk protein hydrolyzate in which the methional content is reduced to 600 ppb or less, or the dimethyl trisulfide content is reduced to 40 ppb or less. It has physicochemical properties that are not found in the degradation products, and unpleasant odors are reduced.
Since the flavor is further improved by reducing unpleasant odorous substances, jelly, pudding, ice cream, yogurt, juice, milk drink, processed milk, coffee, sports drink, soup, It can be suitably used for a wide variety of foods such as baked foods, milk powder, infant formulas, and liquid foods. Furthermore, it can utilize suitably also for cosmetics, such as a shampoo, a rinse, and a cream, as a cosmetic material.
[0035]
Next, the present invention will be described in detail with reference to test examples.
[Reference test]
This test was performed to measure the odor components of milk protein hydrolysates and confirm the odor of each component.
(1) Sample preparation
1 kg of lactate casein (protein content 85%, manufactured by Unilee France) is dissolved in 10 kg of purified water, 13 g of sodium hydroxide (manufactured by Nippon Soda Co., Ltd.) and 33 g of potassium hydroxide (manufactured by Nippon Soda Co., Ltd.) are added, pH adjusted to 9.3, neutral protease derived from Bacillus genus (trade name: Protease N, manufactured by Amano Enzyme) 1.68 million active units (2,000 active units per gram of protein), alkaline derived from Bacillus bacteria Protease (trade name: Biolase sp-20, manufactured by Nagase Seikagaku Co., Ltd.) 1008,000 activity units (1,200 activity units per gram of protein) and trypsin (trade name: trypsin V. manufactured by Nippon Biocon Co., Ltd.) 5.88 million Add activity units (7,000 activity units per gram of protein), hydrolyze at 50 ° C, monitor enzyme reaction by degradation rate And decomposition rate at the time of 24% and the amino acid liberated rate reached 4.3%, the enzyme was inactivated by heating for 2 seconds at 130 ° C.. This hydrolyzed solution was ultrafiltered through an ultrafiltration membrane module (trade name: SIP 1030, manufactured by Asahi Kasei Co., Ltd.) having a molecular weight cut off of 6,000, and then an adsorption resin (trade name: KS-35, manufactured by Ajinomoto Fine Techno Co., Ltd.). The membrane permeation fraction was concentrated and spray-dried to prepare about 7.5 kg of powdered casein hydrolyzate, which was used as a sample. This was dissolved in distilled water so as to be 5% by mass to obtain a sample solution.
(2) Test method
The sample solution was subjected to solid-phase microextraction gas chromatograph mass spectrometry (hereinafter sometimes abbreviated as GC-MS) according to the following conditions to measure odor components.
a) Measuring equipment
-GC: AGILENT 6890 type
・ MS: AGILENT, 5973 type
・ Column: INNOWAX (trade name, manufactured by AGILENT)
Film thickness: 0.5μm
Length: 30m
Aperture: 0.25mm
b) Method for separating and concentrating odor components
The odor in the headspace was extracted into the fiber and measured for 60 minutes at 37 ° C. by solid phase microextraction (SPME fiber: 50/30 μm Stable Flex DVB / Carboxen / PDMS, manufactured by SUPELCO).
c) Measurement conditions
-GC oven temperature rising condition: 40 ° C, 2 minutes
4 ° C / min (up to 120 ° C)
6 ° C / min (up to 240 ° C), hold for 10 minutes
Gas flow rate: 1.2 ml / min Helium gas
MS ionization voltage: 70 eV
Measurement mode: SCAN (3 SCAN / sec)
Separately, in order to confirm the odor of the odor component measured by the solid phase micro extraction gas chromatograph mass spectrometry method, an odor sniffing test was conducted by the following method. Extraction processing was performed by adding 400 ml of diethyl ether to 600 ml of the sample solution, and then the organic layer was concentrated to 0.5 ml. 1 μl of the concentrate was separated with a gas chromatograph, a glass odor sniffing device was connected to the outlet of the column, and the odor was sniffed, and the peak odor corresponding to the retention time in the solid-phase microextraction gas chromatography mass spectrometry was confirmed.
(3) Test results
The results of this test are as shown in FIG. FIG. 2 is a GC-MS chromatogram of the sample solution.
In the smell sniffing test, odors such as peptide odor, casein odor and sulfur odor were confirmed in the region A (retention time: 16 to 22 minutes) in the figure.
[0036]
[Test Example 1]
This test was performed to determine whether methional contained in milk protein hydrolyzate was quantified and reduced.
(1) Sample preparation
Casein hydrolyzate prepared in the same manner as in Example 1 was used as Test Sample 1. Further, casein hydrolyzate prepared in the same manner as Example 1 except that the multistage thin film steam distillation was not performed in Example 1 was used as a control sample 1. The test sample 1 and the control sample 1 were dissolved in distilled water so as to be 5% by mass and used as sample solutions. The standard substance used was methional (manufactured by Aldrich) dissolved in methanol at 0.5 ppm.
(2) Test method
The sample solution was subjected to solid-phase microextraction according to the following conditions, and methional was quantified by the standard addition method.
a) Measuring equipment
-GC: AGILENT 6890 type
・ Column: INNOWAX (trade name) (manufactured by AGILENT)
Film thickness: 0.5μm
Length: 30m
Aperture: 0.25mm
b) Method for separating and concentrating odor components
The test sample solution and the control sample solution were immersed in a solution to which sodium chloride was added at 37 ° C. for 60 minutes by solid phase microextraction (SPME fiber: 85 μm Polyacrylate Coating), and the odor was extracted and measured on the fiber. Methional was quantified by the standard addition method.
c) Measurement conditions
-GC oven temperature rising condition: 40 ° C, 2 minutes
4 ° C / min (up to 120 ° C)
6 ° C / min (up to 240 ° C), hold for 10 minutes
Gas flow rate: 1.9ml / min Helium gas
・ Detector Chemiluminescence sulfur detector (SCD: manufactured by Seaverse [SIEVERS])
(3) Test results
The results of this test are shown in FIG. FIG. 3 shows the measurement results of methional of the test sample 1 and the control sample 1 by gas chromatography. The arrows in the figure represent methional peaks. Methional is present in region A of FIG. Table 1 shows the results of quantifying the methional peak of each sample.
As a result, the methional content of the control sample 1 was 69 μg per kg of the sample, and the methional content of the test sample 1 was 20 μg per kg of the sample. Therefore, the reduction rate of the methional of the test sample 1 was 71.0. It was found that methional can be effectively reduced by the method for producing a milk protein hydrolyzate of the present invention.
[0037]
[Table 1]

[0038]
[Test Example 2]
This test was conducted to sensorially evaluate the flavor of milk protein hydrolyzate with reduced methional.
(1) Sample preparation
A whey protein hydrolyzate produced in the same manner as in Example 4 was used as test sample 2, and a whey protein produced in the same manner as in Example 4 except that the multistage thin-film steam distillation was not performed (whey (Protein) Hydrolyzate was used as control sample 2, and each solution was prepared in 5% by mass with distilled water and subjected to a sensory test.
(2) Test method
The taste of the test sample 2 and the control sample 2 was organoleptically tested according to the following evaluation method using a panel of 20 men and women from 20 to 40 years old. The flavor in the present invention is determined as good as the less unpleasant odor peculiar to the milk protein hydrolyzate, and judged as bad as the unpleasant odor is high, and the respective flavors are evaluated and judged as follows. It was.
If the flavor is good, the evaluation score is 2 points
If you can't say either, the evaluation score is 1 point
If the flavor is poor, the evaluation score is 0 points
The average value of the evaluation points is calculated,
1.5 points or more: good
0.5 points or more and less than 1.5 points: neither good nor bad
Less than 0.5: Bad
Judgment was made according to the criteria.
(3) Test results
The results of this test are as shown in Table 2. Table 2 shows the result of calculating the average of the evaluation points of the sensory test of the test sample 2 and the control sample 2. As a result, the average evaluation score of the control sample 2 was calculated to be 0.85, which was “not good or bad”, but the test sample 2 was calculated to have an average evaluation score of 1.6. The evaluation result was obtained. Therefore, it was revealed that the milk protein hydrolyzate produced by the method of the present invention was further improved in flavor due to the reduced odor.
[Table 2]

[0039]
[Test Example 3]
This test was conducted in order to sensorially evaluate the content of methional in the milk protein hydrolyzate of the present invention.
(1) Sample preparation
A milk protein (whey protein) hydrolyzate produced by adjusting the degree of deodorization so that the methional content was 400, 600, 800, and 1000 ppb by the same method as in Example 4 was used as a sample. Each was prepared to a 5% by mass solution with distilled water and subjected to a sensory test.
(2) Test method
By using a panel of 20 males and 20 females from 20 years old to 40 years old, the odor of each methional concentration sample was tested sensuously according to the following evaluation method (evaluation point calculation).
“No smell”: 0 points
“Odor of milk protein hydrolyzate product” 1 point
“Slightly unpleasant odor as milk protein hydrolyzate product”: 2 points
"Smelly and uncomfortable as a milk protein hydrolyzate product": 3 points
The average value of the evaluation points was calculated, and “less than 1 point” was determined as an acceptable flavor inspection reference value.
(3) Test results
The results of this test are as shown in Table 3. Table 3 shows the result of calculating the average of the evaluation points of the sensory test for the samples of each methional concentration. As a result, the acceptable flavor test reference value was less than 1 point because the content of methional contained in the milk protein hydrolyzate was 600 ppb or less. Accordingly, it was found that the milk protein hydrolyzate with reduced odor produced by the method of the present invention has a methional content of 600 ppb or less.
[0040]
[Table 3]

[0041]
[Test Example 4]
This test was conducted in order to compare the recovery rate of amino acids when the milk protein hydrolyzate was deodorized by the multistage thin-film steam distillation of the present invention and when it was deodorized by a normal adsorbent.
(1) Sample preparation
Casein hydrolyzate prepared by the same method as in Example 1 (deodorized by multi-stage thin-film steam distillation shown in FIG. 1) was used as an adsorbent (instead of multi-stage thin-film steam distillation in Test Sample 3, Example 1). Casein hydrolyzate prepared by deodorizing according to a conventional method using a trade name: KS-35, manufactured by Ajinomoto Fine Techno Co., Ltd. was used as Control Sample 3. Moreover, the casein hydrolyzate which did not perform the deodorization (multistage thin-film steam distillation) process in Example 1 was prepared as control. The test sample 3, the control sample 3, and the control were all dissolved in distilled water to give a 5% by mass aqueous solution and used for the test.
(2) Test method
In order to compare the recovery rate of amino acids by deodorization treatment, amino acid composition analysis was performed for test sample 3, control sample 3, and control, respectively, and the recovery rate (%) of each amino acid in test sample 3 and control sample 3 relative to control was calculated. Calculated. (3) Test results
The results of this test are as shown in Table 4. Table 4 shows the results of calculating the recovery rate (%) of each amino acid in the test sample 3 and the control sample 3 with respect to the control. As a result, in the test sample 3 deodorized by the multistage thin-film steam distillation, a decrease in the recovery rate of amino acids was hardly confirmed, whereas in the control sample 3 deodorized by the adsorbent, cysteine and With histidine and basic amino acids arginine, lysine, and aromatic amino acids phenylalanine, tryptophan, and tyrosine, a tendency to decrease the recovery rate of amino acids was confirmed, particularly tryptophan (20.0%) and cysteine (66. It became clear that the recovery rate suddenly decreased at 7%. Therefore, when the milk protein hydrolyzate was deodorized by the multi-stage thin film steam distillation of the present invention, it was found that the amino acid recovery rate was better than the deodorization by the known adsorbent in the prior art 1.
[0042]
[Table 4]

[0043]
[Test Example 5]
With respect to the test sample 1 and the control sample 1 prepared by the same method as in Test Example 1, dimethyl trisulfide contained in each sample was quantified and a test for confirming whether or not it was reduced was performed.
Using a dimethyl trisulfide standard substance (manufactured by ACROS) dissolved in methanol at a concentration of 0.01 ppm, the peak (arrow) near 16.5 minutes of the chromatograph shown in FIG. 4 is dimethyl trisulfide. The dimethyl trisulfide contained in the test sample 1 and the control sample 1 was quantified with respect to this peak. Note that dimethyl trisulfide is present in region A in FIG.
The results are shown in Table 5. The content of dimethyl trisulfide was 2.4 μg / kg of sample in the control sample 1 but 1.4 μg / kg of sample in the test sample, and the deodorization process reduced dimethyl trisulfide by 41.7%. There was found.
[0044]
[Table 5]

[0045]
[Test Example 6]
In the same manner as in Test Example 3, the following test was conducted in order to functionally evaluate the content of dimethyl trisulfide in the milk protein hydrolyzate.
(1) Sample preparation
A milk protein (whey protein) hydrolyzate produced by adjusting the degree of deodorization so that the content of dimethyl trisulfide is 20, 40, 60, and 80 ppb, respectively, by the same method as in Example 4. Each sample was prepared into a 5% by mass solution with distilled water and subjected to a sensory test.
(2) Test method
By using a panel of 20 males and 20 females from 20 years old to 40 years old, the odor of each methional concentration sample was tested sensuously according to the following evaluation method (evaluation point calculation).
“No smell”: 0 points
“Odor of milk protein hydrolyzate product” 1 point
“Slightly unpleasant odor as milk protein hydrolyzate product”: 2 points
"Smelly and uncomfortable as a milk protein hydrolyzate product": 3 points
The average value of the evaluation points was calculated, and “less than 1 point” was determined as an acceptable flavor inspection reference value.
(3) Test results
The results of this test are shown in Table 6. Table 6 shows the result of calculating the average of the evaluation points of the sensory test for each sample of dimethyl trisulfide concentration. As a result, it was a milk protein hydrolyzate having a content of dimethyl trisulfide of 40 ppb or less that had an acceptable flavor test reference value of less than 1 point. Therefore, it was found that the milk protein hydrolyzate with reduced odor produced by the method of the present invention has a dimethyl trisulfide content of 40 ppb or less.
[0046]
[Table 6]

[0047]
【Example】
EXAMPLES Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to a following example.
[0048]
[Example 1]
1 kg of lactate casein (protein content 85%, manufactured by Unilee France) is dissolved in 10 kg of purified water, 13 g of sodium hydroxide (manufactured by Nippon Soda Co., Ltd.) and 33 g of potassium hydroxide (manufactured by Nippon Soda Co., Ltd.) are added, pH adjusted to 9.3, neutral protease derived from Bacillus genus (trade name: Protease N, manufactured by Amano Enzyme) 1.68 million active units (2,000 active units per gram of protein), alkaline derived from Bacillus bacteria Protease (trade name: Biolase sp-20, manufactured by Nagase Seikagaku Co., Ltd.) 1008,000 activity units (1,200 activity units per gram of protein) and trypsin (trade name: trypsin V. manufactured by Nippon Biocon Co., Ltd.) 5.88 million Add activity units (7,000 activity units per gram of protein), hydrolyze at 50 ° C, monitor enzyme reaction by degradation rate And decomposition rate at the time of 24% and the amino acid liberated rate reached 4.3%, the enzyme was inactivated by heating for 2 seconds at 130 ° C.. This hydrolyzed solution was ultrafiltered with an ultrafiltration membrane module (trade name: SIP1030, manufactured by Asahi Kasei Co., Ltd.) having a molecular weight cut off of 6,000, and then the membrane permeate fraction was concentrated, spray-dried, and powdered. About 7.5 kg of casein hydrolyzate was obtained.
5 kg of the obtained casein hydrolyzate was dissolved in 95 kg of purified water, the solution concentration was 5%, the temperature was 50 ° C., the treatment flow rate was 50 l / h, and the rotational speed of the rotating body of the gas-liquid contact device was 40 s.^-1(240 rpm), steam and hot air from the bottom of the contact tower 5 kg / h, 1 m respectively³/ H was blown, and the odor component of the casein hydrolyzate was transferred to steam at a vacuum pressure of -70 kPa to perform steam distillation.
The casein hydrolyzate treatment solution produced by the above method was tested by the above test method, and as a result, the content of methional was 20 ppb and the content of dimethyl trisulfide was 1.4 ppb, and it was used as it is for food, cosmetics, etc. It was an excellent one possible.
[0049]
[Example 2]
1 kg of commercially available whey protein concentrate (protein content 75%, manufactured by Warrnambool Cheese & Butter) was dissolved in 9 kg of purified water, and 5.5 g of sodium hydroxide (manufactured by Nippon Soda Co., Ltd.) was added to adjust the pH. Adjusted to 7.5, papain (trade name: Papain 300, manufactured by Nippon Biocon) 38255,000 active units (5,100 active units per gram of protein), trypsin (trade name: PTN 6.0S, Novozymes Japan) 11.55,000 active units (1,500 active units per gram of protein) and 135,000 active units of protease derived from lactic acid bacteria Lactobacillus helveticus (180 active units per gram of protein) When the degradation rate reaches 15.8% and the amino acid release rate reaches 6.1%, the enzymatic reaction is monitored by the degradation rate. In heated for 2 seconds to inactivate the remaining enzyme, cooled to 10 ° C.. This hydrolyzed solution was ultrafiltered through an ultrafiltration membrane module (trade name: SLP-1053, manufactured by Asahi Kasei Co., Ltd.) having a molecular weight cut-off of 10,000, and then the membrane permeation fraction was adjusted to a solution concentration of 5% and a temperature of 50 ° C , Treatment flow rate 50 l / h, rotation speed of rotating body of gas-liquid contact device 35^-1(210 rpm), steam and hot air from the bottom of the contact tower are 7 kg / h and 0.5 m respectively.³The odor component of the whey protein hydrolyzate was transferred to steam at a vacuum pressure of −60 kPa, and steam distilled. Further concentration and spray drying yielded about 0.75 kg of powdered whey protein hydrolyzate.
The obtained whey protein hydrolyzate was tested by the above test method. As a result, the degradation rate was 15.8%, the amino acid release rate was 6.1%, the methional content was 350 ppb, and the dimethyl trisulfide content. Was 23 ppb and was excellent as it can be used as it is in foods, cosmetics and the like.
[0050]
Example 3
Lactic casein (protein content 85%, New Zealand Milk Products) 1 kg is dissolved in 8 kg of purified water, 25 g of sodium hydroxide (Nihon Soda Co., Ltd.) is added to adjust the pH to 7.0, and pancreatin (Trade name: Pancreatin F. manufactured by Amano Enzyme) 425,000 active units (500 active units per gram of protein) and 1.2 million active units of protease derived from lactic acid bacteria Lactobacillus helvetics (1,410 active units per gram of protein) ) And hydrolyzed at 50 ° C., and the enzyme reaction was monitored by the degradation rate. When the degradation rate reached 35% and the amino acid release rate reached 40%, the enzyme was lost by heating at 130 ° C. for 2 seconds. Allowed to cool to 10 ° C. The hydrolyzed solution was clarified by diatomaceous earth filtration, and the clarified solution was concentrated. Further, the clarified liquid was spray-dried to obtain about 0.82 kg of powdered casein hydrolyzate. 0.8 kg of the obtained casein hydrolyzate was dissolved in 15.2 kg of purified water, the solution concentration was 5%, the temperature was 50 ° C., the treatment flow rate was 35 l / h, and the rotational speed of the rotating body of the gas-liquid contact device was 45 s.^-1(270 rpm), steam and hot air from the bottom of the contact tower 3 kg / h, 0.5 m respectively³The odor component of the casein hydrolyzate was transferred to steam at a vacuum pressure of −60 kPa, and steam distilled.
The casein hydrolyzate treatment solution produced by the above method was tested by the above test method. As a result, the content of methional was 15 ppb, and the content of dimethyl trisulfide was 1.0 ppb. It was an excellent one possible.
[0051]
Example 4
10 kg of commercially available whey protein concentrate (protein content 75%, manufactured by Mirai) was dissolved in 90 kg of purified water, and 55 g of sodium hydroxide (manufactured by Saneigen FFI Co., Ltd.) was added to adjust the pH to 7.5. Adjusted. Subsequently, papain (trade name: Papain 300, manufactured by Nippon Biocon) 48.8 million active units (6,500 active units per gram of protein) and trypsin (trade name: PTN 6.0S; manufactured by Novozymes Japan) 46.9 million active units (6,250 activity units per gram of protein) is added, hydrolyzed at 50 ° C, the enzymatic reaction is monitored by the degradation rate, and heated at 130 ° C for 2 seconds when the degradation rate reaches 13.7% The enzyme was deactivated and cooled to 10 ° C.
This hydrolyzate was treated with an ultrafiltration membrane module (trade name: SLP-1053, manufactured by Asahi Kasei Co., Ltd.) having a molecular weight cut-off of 10,000, the membrane permeate fraction was concentrated and spray-dried, and powdered whey About 7.3 kg of protein hydrolyzate was obtained.
6 kg of the obtained whey protein hydrolyzate was dissolved in 114 kg of purified water, the solution concentration was 5%, the temperature was 50 ° C., the treatment flow rate was 70 l / h, and the rotational speed of the rotating body of the gas-liquid contact device was 45 s.^-1(270 rpm), steam and hot air from the bottom of the contact tower are 7 kg / h and 1 m, respectively.³The odor component of the whey protein hydrolyzate was transferred to steam at a vacuum pressure of −65 kPa, and steam distilled.
The whey protein hydrolyzate produced by the above method was tested by the above test method, and as a result, the content of methional was 500 ppb and the content of dimethyl trisulfide was 35 ppb, which can be used as it is for food, cosmetics and the like. It was excellent.
[0052]
Example 5
10 kg of whey protein concentrate (protein content 75%, manufactured by Mirai Co., Ltd.) is dissolved in 70 kg of purified water, and neutral protease derived from Bacillus bacteria (trade name: Protease N. manufactured by Amano Enzyme Co., Ltd.) 18 million activities Units (2,400 active units per gram of protein) and 680,000 active units of protease derived from lactic acid bacteria Lactobacillus helveticus (90 active units per gram of protein) are added and hydrolyzed at 50 ° C. When the degradation rate reached 23% and the amino acid liberation rate reached 11%, the enzyme was inactivated by heating at 85 ° C. for 6 minutes and cooled to 10 ° C. The hydrolyzate was ultrafiltered with an ultrafiltration membrane module (trade name: SEP-3010, manufactured by Asahi Kasei Co., Ltd.) having a molecular weight cut-off of 3,000, and a solution containing the obtained whey protein hydrolyzate was obtained. Concentrated and spray-dried to obtain about 7.4 kg of powdered whey protein hydrolyzate.
6 kg of the obtained whey protein hydrolyzate was dissolved in 114 kg of purified water, the solution concentration was 5%, the temperature was 50 ° C., the treatment flow rate was 100 l / h, and the rotational speed of the rotating body of the gas-liquid contact device was 40 s.^-1(240 rpm), 10 kg / h each of steam and hot air from the bottom of the contact tower, 2 m³The odor component of the whey protein hydrolyzate was transferred to steam at a vacuum pressure of −60 kPa, and steam distilled.
The whey protein hydrolyzate produced by the above method was tested by the above test method, and as a result, the content of methional was 450 ppb and the content of dimethyl trisulfide was 30 ppb, which can be used as it is for foods, cosmetics and the like. It was excellent.
[0053]
【The invention's effect】
As described in detail above, the present invention relates to a method for producing a milk protein hydrolyzate having a significantly reduced odor and the milk protein hydrolyzate, and the effects exhibited by the present invention are as follows.
(1) By the method of the present invention, a milk protein hydrolyzate with reduced odor that can be applied to a wide range of uses can be produced.
(2) Since the odor is reduced, the milk protein hydrolyzate of the present invention can be suitably used as a raw material for various foods and cosmetics.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a multistage thin film gas-liquid contact device used in a preferred embodiment of the present invention.
FIG. 2 is a GC-MS chromatogram of milk protein hydrolyzate in the reference test.
3 is a gas chromatogram of test sample 1 and control sample 1 of Test Example 1. FIG.
4 is a gas chromatogram of Test Sample 1 and Control Sample 1 of Test Example 5. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Multistage type gas-liquid contact apparatus, 1A ... Contact tower, 2A ... Inlet of to-be-processed liquid, 4A ... Inlet of gas, 6A ... Outlet of to-be-processed liquid, 8A ... Outlet of gas, 9 ... Rotating shaft, 10 ... Rotation Body, 13 ... curved buttocks, 20 ... saucer

Claims (6)

Hydrolysis step of hydrolyzing milk protein with protease to obtain milk protein hydrolyzate, and odorous substances contained in the milk protein hydrolyzate are subjected to steam distillation using a multi-stage thin film gas-liquid contact device A method for producing a milk protein hydrolyzate with reduced odor, characterized by comprising a deodorizing step that reduces the odor.   2. The method for producing a milk protein hydrolyzate with reduced odor according to claim 1, wherein the odor substance reduced by the deodorization step is methional or dimethyl trisulfide. In the deodorizing step, the content of the methional is set to 15 ppb or more and 600 ppb or less of the total mass of the milk protein hydrolyzate, or the content of the dimethyl trisulfide is set to 1 of the total mass of the milk protein hydrolyzate. The method for producing a milk protein hydrolyzate with reduced odor according to claim 2, wherein the odor is reduced to 0.0 ppb or more and 40 ppb or less.   The said deodorizing process is performed without performing drying after obtaining the hydrolyzate containing a milk protein hydrolyzate in the said hydrolysis process, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. A method for producing a milk protein hydrolyzate with reduced odor. A milk protein hydrolyzate produced by the method for producing a milk protein hydrolyzate according to any one of claims 1 to 4, wherein the content of methional is 15 ppb or more and 600 ppb or less. A milk protein hydrolyzate produced by the method for producing a milk protein hydrolyzate according to any one of claims 1 to 4, wherein the content of dimethyl trisulfide is 1.0 ppb or more and 40 ppb or less. .

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