【０００１】
【発明の属する技術分野】
本発明は穀物、穀物粉、穀物加工食品、特に、米、米粉、米加工食品に関する。より詳細には、腸機能を改善し、かつ血糖値の急激な上昇を抑制する健康食品として好適な穀物および穀物粉ならびにその製造方法、特に、米および米粉ならびにその製造方法に関する。
【０００２】
【従来の技術】
穀物は人類の主要な炭水化物供給源であり、特に米は日本人の主食として欠かせないものである。中でも玄米は白米に比べて栄養価が高く、食物繊維も多量に含むことから腸などの消化管の働きを正常に保ち、便通を良くすることができるなど健康食品としても最近特に注目されている。穀物を食するための加工方法としては麦類は粉にした後、パンやクッキーなどに焼成加工し、米は炊飯されたり粥状にするのが一般的である。
【０００３】
しかしながら、上記のような加熱加工した穀物加工品は澱粉が糊化され消化吸収性が高くなっているために大腸などの下部消化管に到達することなく小腸などで吸収される割合が大きく、その腸機能の改善効果は含まれる数％の食物繊維に依存しているため限りがある。一方、糊化されていない澱粉、いわゆるβ澱粉はヒトの消化酵素の影響を受け難いため、下部消化管まで到達し、腸内微生物の発酵を受けて短鎖脂肪酸となり、腸の蠕動運動を活発にすることで便秘を改善するとともに、乳酸菌やビフィズス菌に資化されることでこれらの腸内善玉菌を増やし、肌美容や様々な疾病に関連していると言われる腸内環境を整える働きをする。澱粉は穀類が最も多く持つ成分であるため、その効果は食物繊維に比べ非常に大きくなる。
【０００４】
また穀物加工品は澱粉が糊化され消化吸収性が高くなっているためにカロリーが高い。また、糊化された澱粉のような吸収性の高い糖質は血糖値を急激に上昇させるため、インスリンが過度に分泌されることから、インスリン非感受性の糖尿病に繋がりやすく、すでに糖尿病に罹患している人にとっても、病状をさらに悪化させる恐れがある。さらに急激に血糖値が上昇した場合、過剰なブドウ糖はインスリンの働きで脂肪に変換合成され、脂肪組織に取込まれることにより肥満を招く。これがさらに糖尿病を悪化させる。一方β澱粉は吸収され難いためカロリーが摂取され難く、血糖値の急激な上昇を招かない。以上のような効果を得る目的には玄米などの穀物は澱粉を消化吸収性の高い糊化澱粉ではなく、β澱粉の状態で摂取するのが適している。また玄米はビタミンＢ１などのビタミン類が豊富に含まれているが、加熱加工した玄米は玄米本来のビタミンなどの栄養素が熱によって壊れてしまうという欠点もある。
【０００５】
β澱粉の状態で穀物の澱粉を摂取する方法として生玄米をそのまま粉砕し熱を加えない加工を施して食することが提案されている（特許文献１、特許文献２、特許文献３参照。）。しかし、生玄米をβアミラーゼ・プルラナーゼ法にて測定した糊化度は約１５〜２５％である。糊化度とは穀物粉末に含まれる総澱粉のうち糊化澱粉の割合を意味する。つまり上記の方法においても１５〜２５％は消化されやすい糊化澱粉であり、さらにβ澱粉が多い状態、すなわち糊化度が低い状態で穀物を食べることにより上述の効果はより高まると考えられる。また穀物を生の状態で食べようとした場合、加熱殺菌を経ていないため病原性の微生物が殺菌されておらず、衛生的に問題がある。
【０００６】
一方、糊化度の上昇を抑制された穀物の製造法として小麦粉を飽和水蒸気を導入した加圧状態の密封系攪拌機にて攪拌機での周速度５〜２０ｍ／秒、滞留時間２〜２０秒の条件下に攪拌機からの排出時の小麦粉品温が６５〜８０℃になるように湿熱処理する方法が提案されており、その糊化度は生の未処理小麦粉とほぼ同じであることが記載されている（特許文献４参照。）。また同じく糊化度の上昇を抑制された玄米粉の製造方法として１０５℃から２１０℃の温度で６０〜２５０秒間、望ましくは１２０℃〜１３０℃の温度で１００〜２００秒間、玄米を過熱水蒸気と耐圧密閉容器内で接触させる処理を行う方法により糊化度を生と同程度（約２０％）に維持して処理する方法が提案されている（特許文献５参照。）。
【０００７】
しかしながら、それぞれの技術の目的は加工食品の製造に適するように穀物粉の物性を改変することであり、また、健常者向けの食品を前提としているため健常者での消化性を考慮し、糊化度を生の状態より低くするようには技術が構成されていない。よって、従来の穀物粉の製造方法に比べ糊化度は抑制されているものの、生穀物と同等か、生穀物よりも糊化澱粉が多く、より多くのβ澱粉を食するという本発明の目的は達成できていない。
【０００８】
なお、澱粉を湿熱処理することにより平衡水分の変化、Ｘ線回折図の変化、澱粉粒の膨潤性の変化、糊化開始温度の上昇などが知られている。このような性質を応用し、穀類に湿熱処理を施した技術として、米を湿熱処理した場合の糊化度をグルコアミラーゼ法で測定し、原料米の糊化度が２３．８％に対して湿熱処理した米は３６．２〜７６．０％と原料米より高い値となることが記載されている（特許文献６参照。）。また、パンの製造に玄米を使用する際にパン生地製造時の粘性を抑制することを目的に、澱粉を糊化しにくいように改変するため、９０℃以上１２０℃未満の温度で５０〜９０分間湿熱処理を施す技術も提案されており加熱時の糊化が抑制されることが記載されているが、処理穀物粉自体の糊化度については記載がない（特許文献７参照。）。以上の様に穀物の糊化度を生の状態以下に低下させる技術はこれまで提案されていない。
【０００９】
【特許文献１】
特開平０３−１６８０６１号公報
【特許文献２】
特開平０４−４５７５８号公報
【特許文献３】
特開平１０−２４８５０８号公報
【特許文献４】
特開２０００−８３５６９号公報
【特許文献５】
特開平４−４５７５７号公報
【特許文献６】
特開平７−２５９０２号公報
【特許文献７】
特開２００２−４５１３０号公報
【００１０】
【発明が解決しようとする課題】
本発明は穀物、特に、米、特に、玄米をよりカロリーが摂取され難く、血糖値の上がり難い状態で摂取するため、生穀物より糊化度が低い穀物および穀物粉ならびにこれらを加工した食品を提供することを目的としている。
【００１１】
【課題を解決するための手段】
本発明者は上記課題を解決するべく鋭意検討した結果、水分含量２５％以下の生穀物を過熱水蒸気処理することにより、生穀物より糊化度が低下し、かつ加熱せずに食しても安全な程度に微生物が抑制されていること、および玄米を処理した場合、生玄米のビタミンが維持されていることを見出し、本発明の完成に至った。
すなわち、本発明の要旨は
（１） 生穀物より糊化度が低く、かつ衛生的な穀物および穀物粉、ならびに
（２） 生玄米より糊化度が低く、かつ生玄米のビタミン含量が保持されていることを特徴とする玄米および玄米粉。ならびに
（３）前記記載の食品組成物
に関する。
【００１２】
本発明に使用する穀物は一般に流通している生の穀物で良いが、水分が２５％以下であることが必要である。これ以上の水分含量であると、過熱水蒸気処理による加熱で逆に澱粉の糊化が起こってしまうため望ましくない。よって、水分は２５％以下であることがより望ましい。下限値としては特に制約はないが、３％以下に乾燥しようとした場合、かなりの熱をかける必要があるため、栄養成分の劣化が激しくなる。よって、３％以上の水分値が好ましい。過熱水蒸気処理は数秒（約１〜１０秒間）、１４０℃〜１８０℃の過熱水蒸気と接触させることによって行われる。過熱水蒸気とは、飽和水蒸気をさらに過熱していくことで、圧力は変化せずに得られる高い温度の蒸気である。過熱水蒸気は飽和水蒸気のように処理する穀物を湿らせることなく、熱処理が行えるという特徴を持つため本発明に最適の加工方法である。また、乾燥工程が必要ないため、工程が簡素になるというメリットがある。
【００１３】
使用する機器設備は上記条件を達成できるものであれば、どのようなものでも良いが、気流式殺菌装置は本条件を達成するために適している。穀物粒のまま、もしくは穀物粒を半分から４分の１程度に粗粉砕した状態で加工する場合、原料に過熱水蒸気の熱が均一に伝わり難いため、過熱水蒸気の温度は１５５℃以上が望ましく、穀物の色や焦臭がつくなどの香味の劣化や栄養成分の劣化を防ぐために１８０℃以下とすることが望ましい。粉体を調整する場合、穀物粒もしくは粗粉砕した穀物粒を湿熱処理後、粉砕機で粉体とすることができる。また予め穀物を粉砕し粉体とした後、湿熱処理することもできる。この場合、原料に熱が均一に伝わりやすいため、やや処理温度は低くても良く、１４０℃以上が望ましい。また過熱水蒸気に接触させる時間は長すぎた場合色や味栄養成分の劣化を招くため、数秒（約１〜１０秒）の短時間が望ましい。ただし、予め粉体を調整し湿熱処理した場合、気流式殺菌装置の入り口付近から漏れる蒸気により糊化した粉体がへばりつき、生産性が悪くなるため、湿熱処理後粉砕するのが好ましい。
【００１４】
粉砕に使用する粉砕機は通常使用するもので良いが、品質の劣化を防ぐため、過度の摩擦熱は抑制するのが好ましい。なお、本発明の穀物および穀物粉は澱粉を糊化せずに食する必要があるため、通常の食品製造で行われる加熱加工が困難である。よって加熱加工の際に同時になされる殺菌が行えないため、本発明の穀物および穀物粒は微生物数が抑制され大腸菌群陰性であることが必要である。上記過熱水蒸気処理の結果、微生物も殺菌され、大腸菌群を陰性とすることができるため、加熱加工を行わずに食することが可能となる。
なお、オートクレーブなどにより１００℃〜１３０℃程度の比較的低温で６０秒以内の短時間湿熱処理を行うことによっても糊化度は生穀物より低く抑えることができるが、本発明よりその低下率は低く、また処理温度が低いために殺菌が不充分となり非加熱で食する本発明の目的には適さない。また１００℃〜１３０℃程度でさらに長い時間湿熱処理を行うと、菌数は減るが糊化度は逆に高くなるため、やはり本発明の目的には適さない。
【００１５】
上記方法で製造した穀物を食する方法として、そのまま粉体を水、牛乳、豆乳、ジュースなどに溶かしたり、マルチトールなどの難消化性の糖質を加えて食することができる。このとき、他の食材と混ぜることも可能である。ただし、６０℃以上の水分を多く含む液体を加えると、澱粉の糊化が進むため好ましくない。さらに食べ易くするために、本発明の穀物を使用して食品加工品を製造する場合、水分の多い状態で加熱を行うと、澱粉の糊化が起こるため、加熱を用いない製造方法が必要である。例えば、液体に溶解した後、凍結乾燥を行いスナック状に加工したり、難消化性の液糖を加え、固めてオコシ状や栄養バー状に加工することができる。加工の際、他の穀類、芋類、糖類、豆類、種実類、野菜類、果実類、茸類、藻類、魚介類、肉類、卵類、乳類、油脂類、調味料、香辛料、香料、増粘安定剤、乳化剤、甘味料、保存料、着色料、酸化防止剤、酸味量などの原料を加えることも可能である。なお本発明の穀物を食する場合、消化性の糖質やこれを含む原料は血糖値を上げ易いため、少量であれば構わないが、使用しないほうが好ましい。
【００１６】
【発明の実施の形態】
以下、本発明に係る穀物および穀物粉並びに穀物加工食品、特に玄米および玄米粉末ならびに玄米加工食品を実施例に基づいてさら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。なお、本発明に使用する穀物としては、特に種類は限定されないが、米類、雑穀類（アマランサス、粟、黍、稗、もろこし、キヌア）、麦類（燕麦、大麦、小麦、はと麦、ライ麦）、そば、とうもろこし、などが挙げられる。籾のある穀物は籾がついたままでも処理は可能であるが、過熱水蒸気処理を均一に行うためには、籾を外したほうが望ましい。搗精は行っても行わなくても構わないが、栄養成分的には精白は行わないほうが好ましい。特に玄米はβ澱粉だけでなくビタミン類などの栄養素が豊富に摂取できるので好ましい。
【００１７】
本発明に使用する玄米としては未精製の米であれば銘柄、産地等は何ら限定されることはない。また、穀物を予め洗ったり、水または５０℃以下の温水に浸漬、もしくは５０℃以下の高湿度下にて発芽させた穀物を使用しても良い。また、上記穀物の割砕物、粉砕物も使用できる。また、上記穀物は単独で使用しても良いが、併用することもできる。それぞれ穀物は処理前に水分が２５％以下になるように乾燥する。乾燥する手段としては通常の乾燥法が利用できるが、水分３０％以上含まれる乾燥初期はできるだけ加熱を抑え、品温を６０℃以下で乾燥するのが好ましい。
【００１８】
湿熱処理は１４０℃〜１８０℃の過熱水蒸気に１〜１０秒間接触できる条件が達成できる機械であればどのような機械装置を使用しても良いが、過熱水蒸気を使用して殺菌を行う機械が好適に使用できる。例として気流式殺菌装置、高速攪拌式殺菌装置などが挙げられる。穀物を粉体にして処理をする場合、粉砕機は通常穀物粉を作るために使用されているもので構わない。
【００１９】
【実施例１】
水分含量を１５％に調整した玄米を気流式殺菌装置（キッコーマン社製）を用いて次の条件にて過熱水蒸気処理を行った。
圧力−過熱水蒸気温度−処理時間：３．０ｋｇ／ｃｍ２Ｇ−１７０℃−３秒
【実施例２】
水分含量を１５％に調整した玄米を気流式殺菌装置（キッコーマン社製）を用いて次の条件にて過熱水蒸気処理を行った。
・圧力−過熱水蒸気温度−処理時間：２．５ｋｇ／ｃｍ２Ｇ−１６０℃−３秒
【実施例３】
水分含量を１５％に調整した玄米を気流式殺菌装置（キッコーマン社製）を用いて次の条件にて過熱水蒸気処理を行った。
・圧力−過熱水蒸気温度−処理時間：２．０ｋｇ／ｃｍ２Ｇ−１５５℃−３秒
【比較例１】
水分含量を１５％に調整した玄米を気流式殺菌装置（キッコーマン社製）を用いて次の条件にて過熱水蒸気処理を行った。
・圧力−過熱水蒸気温度−処理時間：１．５ｋｇ／ｃｍ２Ｇ−１５０℃−３秒
【００２０】
結果を表１に示す。なお、糊化度はβ−アミラーゼ・プルラナーゼ法にて、一般生菌数は標準寒天培地法、大腸菌群はＢＧＬＢ法にて測定した。
【００２１】
【表１】
【００２２】
１５５℃以上の過熱水蒸気により処理した実施例１〜３は、糊化度が１７．５〜１２．０％であり、処理前に比べ糊化度が１２．５〜４０％低減した、生玄米より糊化度が低い玄米が得られた。また、実施例１〜３はともに一般生菌数は３００以下／ｇに低く抑えられ、大腸菌群も陰性であった。またビタミンの残存量も０．３０〜０．３１ｍｇ／１００ｇであり未処理の生玄米と比べ遜色は無かった。
【実施例４】
実施例１にて得た過熱水蒸気処理玄米を粉砕機（スーパーウイングミルＤＭ−２００、（株）三和エンヂニアリング製）にて平均粒径１００μｍの粉体に加工した。
【実施例５】
実施例２にて得た過熱水蒸気処理玄米を粉砕機（スーパーウイングミルＤＭ−２００、（株）三和エンヂニアリング製）にて平均粒径１００μｍの粉体に加工した。
【実施例６】
実施例３にて得た過熱水蒸気処理玄米を粉砕機（スーパーウイングミルＤＭ−２００、（株）三和エンヂニアリング製）にて平均粒径１００μｍの粉体に加工した。
【比較例２】
比較例１にて得た過熱水蒸気処理玄米を粉砕機（スーパーウイングミルＤＭ−２００、（株）三和エンヂニアリング製）にて平均粒径１００μｍの粉体に加工した。
【００２３】
実施例４〜６および比較例２の糊化度、一般生菌数、大腸菌群を測定した結果を表２に示す。
【００２４】
【表２】
【００２５】
粉体に加工しても、糊化度、一般生菌数、大腸菌群の値にほとんど変化はなかった。
【実施例７】
水分含量を１５％に調整した玄米を粉砕機（スーパーウイングミルＤＭ−２００）にて平均粒径５００μｍの粉体に加工した後、気流式殺菌装置を用いて次の条件にて湿熱処理を行った。
圧力−過熱水蒸気温度×処理時間：２．０ｋｇ／ｃｍ２Ｇ−１５５℃×４秒
【実施例８】
水分含量を１５％に調整した玄米を粉砕機（スーパーウイングミルＤＭ−２００）にて平均粒径５００μｍの粉体に加工した後、気流式殺菌装置を用いて次の条件にて湿熱処理を行った。
圧力−過熱水蒸気温度×処理時間：１．５ｋｇ／ｃｍ２Ｇ−１４５℃×４秒
【実施例９】
水分含量を１５％に調整した玄米を粉砕機（スーパーウイングミルＤＭ−２００）にて平均粒径５００μｍの粉体に加工した後、気流式殺菌装置を用いて次の条件にて湿熱処理を行った。
圧力−過熱水蒸気温度×処理時間：１．０ｋｇ／ｃｍ２Ｇ−１４０℃×４秒
【比較例３】
水分含量を１５％に調整した玄米を粉砕機（スーパーウイングミルＤＭ−２００）にて平均粒径５００μｍの粉体に加工し、過熱水蒸気処理はしなかった。
実施例７〜９および比較例３の糊化度、一般生菌数、大腸菌群を測定した結果を表３に示す。
【００２６】
【表３】
【００２７】
１４０℃以上の過熱水蒸気により処理した実施例７〜９は、糊化度が１８．２〜１３．２％であり、処理前の比較例３に比べ糊化度が９〜３４％低減した、比較例３の生玄米粉より糊化度が低かった。また実施例７〜９ともに一般生菌数は３００以下／ｇに低く抑えられ、大腸菌群も陰性であった。
【実施例１０】
実施例４にて作製した過熱水蒸気処理玄米粉を用いて、次の処方にて凍結乾燥を行い、スナック状食品を調整した。
過熱水蒸気処理玄米粉末７０重量部、胡麻５重量部、食塩５重量部、乳糖２０重量部、水１００重量部。
前記原料を混練したペーストをトレーに充填し−２０℃で予備凍結後、２４時間凍結乾燥を行った。
【実施例１１】
実施例４にて作製した過熱水蒸気処理玄米粉を用いて、次の処方にてバー状食品を調整した。過熱水蒸気処理玄米粉末６０重量部、米胚芽油８重量部、ファイバーソル２ＨＬ（還元難消化性デキストリン溶液）１５重量部、マルチトール７５％溶液１５重量部、胡麻２重量部。前記原料を混練しバー状に成形した。
【００２８】
【発明の効果】
本発明によれば、生穀物より低糊化度でβ澱粉の多い穀物および穀物粉を得ることが出来る。
【００２９】
本発明の低糊化度の穀物、穀物粉を食することにより、より効率的に下部消化管までβ澱粉を届け、腸内細菌叢を活性化し腸機能を整えることにより各種疾病を予防する食品を提供することができる。また、カロリーが低く、血糖値の急激な上昇を抑制することで糖尿病の予防、悪化防止に効果が有り、かつ栄養豊富で衛生的な食品を提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to cereal, cereal flour, processed cereal food, particularly rice, rice flour, processed rice food. More specifically, the present invention relates to cereals and cereal flours suitable as health foods for improving intestinal function and suppressing a rapid increase in blood sugar level, and a method for producing the same, particularly rice and rice flour and a method for producing the same.
[0002]
[Prior art]
Grains are a major source of carbohydrates for humankind, and rice is particularly important as a Japanese staple food. Among them, brown rice has recently attracted particular attention as a health food, as it has a higher nutritional value than white rice and contains a large amount of dietary fiber, so that it can maintain the function of the digestive tract such as the intestine and improve bowel movements. . As a processing method for eating cereals, wheat is generally ground into flour and then baked into bread or cookies, and rice is cooked or porridge.
[0003]
However, as for the processed grain product which has been heat-processed as described above, the starch is gelatinized and the digestibility is increased, so that a large proportion of the processed grain product is absorbed in the small intestine without reaching the lower digestive tract such as the large intestine. The effect of improving intestinal function is limited because it depends on a few percent of dietary fiber. On the other hand, non-gelatinized starch, so-called β-starch, is less susceptible to the effects of human digestive enzymes, reaches the lower gastrointestinal tract, undergoes fermentation of intestinal microbes to become short-chain fatty acids, and activates intestinal peristalsis. In addition to improving constipation, it is used by lactic acid bacteria and bifidobacteria to increase these good bacteria in the intestine, and to regulate the intestinal environment which is said to be related to skin beauty and various diseases do. Since starch is the most common component of cereals, its effect is much greater than dietary fiber.
[0004]
Processed cereals have high calories because starch is gelatinized and digestibility is high. In addition, highly absorbable carbohydrates such as gelatinized starch rapidly increase blood sugar levels, resulting in excessive secretion of insulin, which is likely to lead to insulin-insensitive diabetes. For those who do, there is a risk that the condition may be further exacerbated. When the blood glucose level rises more rapidly, excess glucose is converted to fat by the action of insulin and synthesized, and is taken up by adipose tissue, causing obesity. This further exacerbates diabetes. On the other hand, β-starch is hard to be absorbed, so it is difficult to ingest calories and does not cause a rapid rise in blood sugar level. For the purpose of obtaining the above-mentioned effects, it is suitable that grains such as brown rice take starch in the form of β-starch instead of gelatinized starch having high digestibility and absorptivity. Brown rice is rich in vitamins such as vitamin B1, but brown rice that has been heat-processed also has the disadvantage that nutrients such as brown rice's natural vitamins are destroyed by heat.
[0005]
As a method of ingesting cereal starch in the state of β-starch, it has been proposed to grind raw brown rice as it is, and to process it without applying heat (see Patent Literature 1, Patent Literature 2, Patent Literature 3). . However, the degree of gelatinization of raw brown rice measured by the β-amylase pullulanase method is about 15 to 25%. The gelatinization degree means the ratio of gelatinized starch to the total starch contained in the cereal powder. That is, even in the above method, 15 to 25% is gelatinized starch which is easily digested, and it is considered that the above-mentioned effect is further enhanced by eating cereals in a state where β-starch is large, that is, in a state where gelatinization degree is low. In addition, when trying to eat cereals in a raw state, pathogenic microorganisms are not sterilized because they have not been subjected to heat sterilization, which is a hygienic problem.
[0006]
On the other hand, as a method for producing a grain in which an increase in the degree of gelatinization was suppressed, wheat flour was introduced into a sealed stirrer in a pressurized state in which saturated steam was introduced, at a peripheral speed of 5 to 20 m / sec and a residence time of 2 to 20 sec. A method has been proposed in which wet heat treatment is performed so that the flour temperature at the time of discharge from the stirrer is 65 to 80 ° C. under the conditions, and it is described that the degree of gelatinization is almost the same as that of raw untreated flour. (See Patent Document 4). Similarly, as a method for producing brown rice flour in which the increase in the degree of gelatinization is suppressed, brown rice is heated with steam at 105 ° C to 210 ° C for 60 to 250 seconds, preferably at 120 ° C to 130 ° C for 100 to 200 seconds. A method has been proposed in which a treatment is performed while maintaining the degree of gelatinization at about the same as that of raw (about 20%) by a method of performing contact treatment in a pressure-resistant closed container (see Patent Document 5).
[0007]
However, the purpose of each technology is to modify the physical properties of cereal flour so that it is suitable for the production of processed foods. No technology has been configured to reduce the degree of conversion below the raw state. Therefore, although the degree of gelatinization is suppressed as compared with the conventional method for producing cereal flour, the purpose of the present invention is that the amount of gelatinized starch is the same as that of raw cereal, or that more gelatinized starch is consumed than raw cereal, and more β-starch is consumed. Has not been achieved.
[0008]
It is known that the starch is subjected to wet heat treatment to change the equilibrium moisture, change the X-ray diffraction pattern, change the swelling property of the starch granules, increase the gelatinization start temperature, and the like. Utilizing such properties, as a technique of subjecting cereals to wet heat treatment, the degree of gelatinization when rice is subjected to wet heat treatment is measured by the glucoamylase method, and the degree of gelatinization of the raw rice is 23.8%. It is described that the moisture-heat treated rice has a higher value of 36.2 to 76.0% than that of the raw rice (see Patent Document 6). In addition, in order to suppress the viscosity during the production of bread dough when using brown rice in the production of bread, in order to modify the starch hardly gelatinize, wet at a temperature of 90 ℃ or more and less than 120 ℃ 50-90 minutes A technique of performing heat treatment has also been proposed, and it is described that gelatinization during heating is suppressed, but there is no description about the gelatinization degree of the treated cereal flour itself (see Patent Document 7). As described above, no technique has been proposed so far to reduce the degree of gelatinization of cereals to below the raw state.
[0009]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 03-168061 [Patent Document 2]
JP-A-04-45758 [Patent Document 3]
JP 10-248508 A [Patent Document 4]
Japanese Patent Application Laid-Open No. 2000-83569 [Patent Document 5]
JP-A-4-45757 [Patent Document 6]
JP-A-7-25902 [Patent Document 7]
JP-A-2002-45130
[Problems to be solved by the invention]
The present invention, in order to ingest grains, especially rice, particularly brown rice, in a state in which calories are less likely to be ingested and blood sugar level is hardly increased, a grain and a flour having a lower degree of gelatinization than raw grains and foods in which these are processed. It is intended to provide.
[0011]
[Means for Solving the Problems]
The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, by subjecting raw cereal having a water content of 25% or less to superheated steam treatment, the degree of gelatinization is lower than that of raw cereal, and it is safe to eat without heating. The present inventors have found that the microorganisms are suppressed to a certain extent and that the brown rice is treated to maintain the vitamins of the unbrown rice, thereby completing the present invention.
That is, the gist of the present invention is that (1) the degree of gelatinization is lower than that of raw cereals, and sanitary grains and cereal flour; and (2) the degree of gelatinization is lower than that of raw brown rice, and the vitamin content of raw brown rice is maintained. Brown rice and brown rice flour, characterized in that: And (3) a food composition as described above.
[0012]
The cereal used in the present invention may be a commercially available raw cereal, but it is necessary that the water content is 25% or less. If the water content is more than this, gelatinization of the starch occurs on the contrary by heating by the superheated steam treatment, which is not desirable. Therefore, the water content is more desirably 25% or less. The lower limit is not particularly limited, but when drying to 3% or less, considerable heat needs to be applied, so that the nutritional components are greatly deteriorated. Therefore, a water value of 3% or more is preferable. The superheated steam treatment is performed by contacting with superheated steam at 140 ° C. to 180 ° C. for several seconds (about 1 to 10 seconds). The superheated steam is a high-temperature steam obtained by further heating the saturated steam, without changing the pressure. Superheated steam is a processing method most suitable for the present invention because it has a feature that heat treatment can be performed without moistening grains to be treated like saturated steam. Further, since a drying step is not required, there is an advantage that the step is simplified.
[0013]
The equipment to be used may be any equipment as long as the above conditions can be achieved, but the air-flow sterilizer is suitable for achieving the conditions. When processing the grains as they are, or when the grains are roughly crushed by about half to one-quarter, the heat of the superheated steam is preferably 155 ° C or higher because the heat of the superheated steam is difficult to be uniformly transmitted to the raw material. The temperature is desirably set to 180 ° C. or lower in order to prevent deterioration of flavor such as color and burning smell of grains and deterioration of nutritional components. In the case of adjusting the powder, the cereal grains or the coarsely crushed cereal grains can be made into a powder by a crusher after wet heat treatment. Alternatively, the grain may be ground in advance to obtain a powder, and then subjected to a wet heat treatment. In this case, since the heat is easily transmitted uniformly to the raw material, the processing temperature may be slightly lower, and is preferably 140 ° C. or higher. In addition, if the time of contact with the superheated steam is too long, the color and taste and nutrient components are deteriorated. Therefore, a short time of several seconds (about 1 to 10 seconds) is desirable. However, when the powder is adjusted in advance and subjected to wet heat treatment, steam that leaks from the vicinity of the inlet of the air-flow sterilizer sticks to the gelatinized powder, thereby lowering productivity. Therefore, it is preferable to pulverize after wet heat treatment.
[0014]
The crusher used for crushing may be a commonly used crusher, but it is preferable to suppress excessive frictional heat in order to prevent quality deterioration. In addition, since the cereal and the cereal flour of the present invention need to be eaten without gelatinizing the starch, it is difficult to perform the heating process performed in normal food production. Therefore, since the sterilization cannot be performed simultaneously during the heat processing, the cereal grains and cereal grains of the present invention need to have a reduced number of microorganisms and be negative for coliform bacteria. As a result of the above superheated steam treatment, the microorganisms are also killed and the coliform group can be made negative, so that it is possible to eat without heating.
In addition, the gelatinization degree can be suppressed to be lower than that of raw cereals by performing a short-time wet heat treatment within 60 seconds at a relatively low temperature of about 100 ° C. to 130 ° C. by an autoclave or the like. It is not suitable for the purpose of the present invention, in which food is eaten without heating due to insufficient sterilization due to the low processing temperature. Further, when the wet heat treatment is performed at about 100 ° C. to 130 ° C. for a longer time, the number of bacteria is reduced, but the gelatinization degree is increased, which is not suitable for the purpose of the present invention.
[0015]
As a method of eating the cereal produced by the above method, the powder can be dissolved as it is in water, milk, soy milk, juice or the like, or can be eaten by adding an indigestible saccharide such as maltitol. At this time, it is also possible to mix with other ingredients. However, it is not preferable to add a liquid containing a large amount of water at 60 ° C. or higher because gelatinization of starch proceeds. In order to make it easier to eat, when manufacturing food products using the cereal of the present invention, if heating is performed in a state of high moisture, gelatinization of starch occurs, so a manufacturing method that does not use heating is required. is there. For example, after being dissolved in a liquid, it can be freeze-dried and processed into a snack form, or hardly added with indigestible liquid sugar and processed into an okoshi form or a nutrition bar form. During processing, other grains, potatoes, sugars, beans, seeds, fruits, vegetables, fruits, mushrooms, algae, seafood, meat, eggs, milk, oils and fats, seasonings, spices, spices, Raw materials such as a thickening stabilizer, an emulsifier, a sweetener, a preservative, a colorant, an antioxidant, and an acidity can be added. In the case of eating the cereal of the present invention, digestible sugars and raw materials containing the same are easy to raise the blood sugar level.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the cereal and cereal flour and processed grain food according to the present invention, particularly brown rice and brown rice powder and processed brown rice food will be described in more detail based on examples, but the present invention is not limited to the following examples Absent. The grains used in the present invention are not particularly limited in kind, but include rice, millet (amaranthus, millet, millet, leeks, sorghum, quinoa), barley (oat, barley, wheat, barley, Rye), buckwheat, corn, and the like. Grains with paddy can be treated with the paddy attached, but it is desirable to remove the paddy in order to uniformly perform the superheated steam treatment. Although milling may or may not be performed, it is preferable not to perform whitening in terms of nutritional components. In particular, brown rice is preferable because it can take in abundant nutrients such as vitamins as well as β-starch.
[0017]
The brown rice used in the present invention is not limited, as long as it is unrefined rice. Further, grains washed in advance, immersed in water or warm water of 50 ° C. or lower, or germinated under high humidity of 50 ° C. or lower may be used. In addition, crushed and crushed products of the above-mentioned grains can also be used. Further, the above-mentioned cereals may be used alone or in combination. Each grain is dried before treatment to a moisture content of 25% or less. As a means for drying, a usual drying method can be used, but it is preferable to suppress the heating as much as possible and to dry the product at a temperature of 60 ° C. or less in the initial stage of drying containing 30% or more of water.
[0018]
The moist heat treatment may be performed using any machine as long as the machine can attain the condition of being able to come into contact with superheated steam at 140 ° C. to 180 ° C. for 1 to 10 seconds. It can be suitably used. Examples include an air-flow sterilizer, a high-speed stirring sterilizer, and the like. In the case of processing the cereal into powder, the crusher may be the one usually used for producing cereal flour.
[0019]
Embodiment 1
The brown rice whose water content was adjusted to 15% was subjected to superheated steam treatment under the following conditions using an air-flow sterilizer (manufactured by Kikkoman Corporation).
Pressure-superheated steam temperature-treatment time: 3.0 kg / cm 2 G-170 ° C.-3 seconds [Example 2]
The brown rice whose water content was adjusted to 15% was subjected to superheated steam treatment under the following conditions using an air-flow sterilizer (manufactured by Kikkoman Corporation).
Pressure-superheated steam temperature-treatment time: 2.5 kg / cm 2 G-160 ° C.-3 seconds [Example 3]
The brown rice whose water content was adjusted to 15% was subjected to superheated steam treatment under the following conditions using an air-flow sterilizer (manufactured by Kikkoman Corporation).
-Pressure-superheated steam temperature-processing time: 2.0 kg / cm < 2 > G-155 [deg.] C-3 seconds [Comparative Example 1]
The brown rice whose water content was adjusted to 15% was subjected to superheated steam treatment under the following conditions using an air-flow sterilizer (manufactured by Kikkoman Corporation).
Pressure-superheated steam temperature-processing time: 1.5 kg / cm 2 G-150 ° C.-3 seconds
Table 1 shows the results. In addition, the gelatinization degree was measured by the β-amylase pullulanase method, the general viable cell count was measured by the standard agar medium method, and the coliform group was measured by the BGLB method.
[0021]
[Table 1]
[0022]
In Examples 1 to 3 which were treated with superheated steam of 155 ° C. or more, the degree of gelatinization was 17.5 to 12.0%, and the degree of gelatinization was reduced by 12.5 to 40% as compared to before the treatment, unbrown rice Brown rice with a lower gelatinization degree was obtained. In Examples 1 to 3, the general viable cell count was suppressed to 300 or less / g, and the coliform group was also negative. Also, the residual amount of vitamins was 0.30 to 0.31 mg / 100 g, which was comparable to untreated raw brown rice.
Embodiment 4
The superheated steam-treated brown rice obtained in Example 1 was processed into a powder having an average particle diameter of 100 μm using a pulverizer (Super Wing Mill DM-200, manufactured by Sanwa Engineering Co., Ltd.).
Embodiment 5
The superheated steam-treated brown rice obtained in Example 2 was processed into a powder having an average particle diameter of 100 μm by a pulverizer (Super Wing Mill DM-200, manufactured by Sanwa Engineering Co., Ltd.).
Embodiment 6
The superheated steam-treated brown rice obtained in Example 3 was processed into a powder having an average particle diameter of 100 μm by a pulverizer (Super Wing Mill DM-200, manufactured by Sanwa Engineering Co., Ltd.).
[Comparative Example 2]
The superheated steam-treated brown rice obtained in Comparative Example 1 was processed into a powder having an average particle diameter of 100 μm by a pulverizer (Super Wing Mill DM-200, manufactured by Sanwa Engineering Co., Ltd.).
[0023]
Table 2 shows the results of measuring the gelatinization degree, the general viable cell count, and the coliform group of Examples 4 to 6 and Comparative Example 2.
[0024]
[Table 2]
[0025]
Even when processed into powder, the gelatinization degree, general viable cell count, and coliform group value hardly changed.
Embodiment 7
After processing the brown rice, whose water content has been adjusted to 15%, into a powder having an average particle diameter of 500 μm using a pulverizer (Super Wing Mill DM-200), wet heat treatment is performed using an air-flow sterilizer under the following conditions. Was.
Pressure - superheated steam temperature × treatment time: 2.0kg / cm 2 G-155 ℃ × 4 seconds Example 8
After processing the brown rice, whose water content has been adjusted to 15%, into a powder having an average particle diameter of 500 μm using a pulverizer (Super Wing Mill DM-200), wet heat treatment is performed using an air-flow sterilizer under the following conditions. Was.
Pressure—superheated steam temperature × treatment time: 1.5 kg / cm 2 G-145 ° C. × 4 seconds [Example 9]
After processing the brown rice, whose water content has been adjusted to 15%, into a powder having an average particle diameter of 500 μm using a pulverizer (Super Wing Mill DM-200), wet heat treatment is performed using an air-flow sterilizer under the following conditions. Was.
Pressure - superheated steam temperature × treatment time: 1.0kg / cm 2 G-140 ℃ × 4 seconds [Comparative Example 3]
Brown rice whose water content was adjusted to 15% was processed into a powder having an average particle diameter of 500 μm by a pulverizer (Super Wing Mill DM-200), and was not subjected to superheated steam treatment.
Table 3 shows the results of measuring the gelatinization degree, the general viable cell count, and the coliform bacteria of Examples 7 to 9 and Comparative Example 3.
[0026]
[Table 3]
[0027]
In Examples 7 to 9 which were treated with superheated steam of 140 ° C. or more, the gelatinization degree was 18.2 to 13.2%, and the gelatinization degree was reduced by 9 to 34% as compared with Comparative Example 3 before the treatment. The gelatinization degree was lower than the raw brown rice flour of Comparative Example 3. In each of Examples 7 to 9, the general viable cell count was suppressed to 300 / g or less, and the coliform group was also negative.
Embodiment 10
Using the superheated steam-treated brown rice powder prepared in Example 4, freeze-drying was performed according to the following formulation to prepare a snack-like food.
70 parts by weight of superheated steam-treated brown rice powder, 5 parts by weight of sesame, 5 parts by weight of salt, 20 parts by weight of lactose, and 100 parts by weight of water.
The paste kneaded with the raw materials was filled in a tray, preliminarily frozen at −20 ° C., and lyophilized for 24 hours.
Embodiment 11
Using the superheated steam-treated brown rice powder prepared in Example 4, a bar-shaped food was prepared according to the following formulation. 60 parts by weight of superheated steam-treated brown rice powder, 8 parts by weight of rice germ oil, 15 parts by weight of Fibersol 2HL (reduced indigestible dextrin solution), 15 parts by weight of a 75% maltitol solution, and 2 parts by weight of sesame. The raw materials were kneaded and formed into a bar.
[0028]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the cereal and the cereal flour which are lower in gelatinization degree than a raw cereal, and have more (beta) starch can be obtained.
[0029]
Eating low-gelatinized grains and flour of the present invention to more efficiently deliver β-starch to the lower gastrointestinal tract, activate intestinal flora and regulate intestinal function, thereby preventing various diseases. Can be provided. In addition, it is possible to provide a nutrient-rich and hygienic food which has a low calorie and is effective in preventing and preventing aggravation of diabetes by suppressing a rapid rise in blood sugar level.
